· Web viewExtinct populations were predominantly in the north of the State, with three of the...

Rare or threatened Tasmanian forest ferns

Executive summary

Acknowledgements

Introduction

Method

Results and Discussion

Summary for all target species

Data gaps and recommendations for further work

References

Appendix 1: Personal communications

Appendix 2: Project brief

Executive summary

Eight species and one subspecies of ferns are identified as occurring in forested habitats in Tasmania and as being rare or threatened. Four of the taxa, Asplenium hookerianum, Asplenium trichomanes subsp. trichomanes, Cheilanthes distans and Hypolepis distans, have been discovered in Tasmania in only the last 20 years and are very rare. The remaining five species, Anogramma leptophylla, Blechnum cartilagineum, Cyathea cunninghamii, Doodia caudata and Pneumatopteris pennigera, have been known from Tasmania since the nineteenth century, and have a history of decline in numbers of individuals and populations and in their geographic range within the State.

Land clearance for agriculture, and to a lesser degree for forestry, has been the major reason for the decline. Consequential, but still dramatic secondary effects of land clearance on the ferns have been competition from exotic weeds, and from trampling by domestic stock which often results in erosion at riparian sites and eventual loss of habitat from flooding.

Future threats to the ferns are seen as mostly from continued clearance of land for agriculture, and from the consequential, and existing, adverse effects of competition from exotic weeds and trampling by stock.

In light of the results of the investigation process, reclassification to five of the target species' conservation status in Tasmania as determined by the Flora Advisory Committee (1994) is required. This involves the addition of one taxon, Asplenium trichomanes subsp. trichomanes (as r1); the uplisting of two species, Anogramma leptophylla (from r2 to e) and Pneumatopteris pennigera (from v to e); and the downlisting of two species, Asplenium hookerianum (from v to r2) and Cheilanthes distans (from e to v). In addition, results also suggest that consideration be given to the following additions and change to National listings as determined by the ANZECC Endangered Flora Network (1993)—Hypolepis distans (add, V), Asplenium trichomanes subsp. trichomanes (will possibly be added with improved knowledge of its mainland Australian status), and Asplenium hookerianum (downlist from V to R).

Only one of the nine fern taxa is presently unreserved in Tasmania. Reservation or improved reservation of some taxa alone is seen as a practical, plausible and workable strategy for ameliorating adverse impacts. In some cases, reservation in combination with a management strategy may be required. Such management strategies usually involve such measures as the cooperation of private land owners and/or the active involvement of interested local groups. The general paucity of knowledge concerning the biology and ecology of the species, and of their life history and of the history of their known populations, hinders the completion of more detailed management prescriptions. Future study in these areas is desirable.

Acknowledgements

The author of this report wishes to acknowledge the support of members of the project steering group, in particular, Stephen Harris (Parks and Wildlife Service, Tasmania). On various occasions, Garry Cruse, Wanda Garrett and Mary Cameron provided great company and support during field studies. Mark Neyland, Andrew Blakesley and David Ziegeler gave invaluable assistance in preparation of the report.

Introduction

Pteridophytes (ferns and allied plants) are vascular plants reproducing from spores. They are separated from the other vascular plant groups (angiosperms and gymnosperms) by being flowerless and reproducing from spores. They are separated from the other cryptogamic plant groups (mosses, liverworts, lichens, algae and fungi) in having separate and free-living gametophyte and sporophyte generations, and in their possession of an internal vascular system.

The true ferns belong to the class Filicopsida. The fern allies belong to three classes, all different from but most closely related to the ferns—Lycopsida (represented in Tasmania by the clubmosses, Isoetes and Selaginella), Psilotopsida (Tmesipteris) and Equisetopsida (no Tasmanian representatives). The fern allies are differentiated from the true ferns by their sporangia being borne on the upper surface of the leaf, by having leaves containing single, unbranched veins, and by the absence of true fronds.

Pteridophytes have evolved from a time in Earth's history when water availability to plant-life was more consistent and abundant than it is today. This, in addition to the fact that (most) pteridophyte species have a subsequent necessity for available moisture to facilitate fertilisation, means that nearly all are found growing in forested habitats or other habitats where there is a greater availability of moisture year-round and where there is protection from the drying effects of sun and wind.

Exactly 100 species of pteridophytes are currently recognised as indigenous to Tasmania (Garrett 1996). This figure comprises 80 ferns and 20 fern allies.

Of the total number of pteridophyte species indigenous to Tasmania, 62 occur in forested habitats, and 17 occur predominantly in either coastal heathland or wetland scrub habitats (Garrett 1996). Of this last figure, all except three are known to extend out of those habitats and into forested habitats. The remainder of Tasmania's pteridophyte species are found in either alpine, truly aquatic, or littoral habitats.

Since European settlement in Tasmania, large tracts of land containing pteridophyte forest habitats have been destroyed chiefly through land clearance for agriculture, forestry and residential settlement. However, the majority of Tasmania's forest-dwelling pteridophytes are either widespread across the State, or, because of their sheltered habitat requirement, are often found in terrain where the topography is unsuitable for utilisation by man (e.g. in gorges, gullies, beside waterfalls). The list of pteridophyte species found growing in these latter sites usually mirrors that of the species found growing in other wet forest types that, because of their surrounding topography, are more susceptible to modification by man.

It is either the forest-dwelling pteridophyte species that are naturally very rare in Tasmania, or those that are rare and restricted to forested habitats where the surrounding topography has been historically conducive to modification by man, that are at most risk of becoming extinct in the State.

None of the species of fern allies occurring in mainland Tasmanian forests is rare or threatened.

This project examines the distribution, population attributes, impacts, and habitat and management requirements of the nine forest-dwelling fern taxa considered to

be at most risk. The project brief and defined project objectives are detailed in Appendix 2.

The fern taxa considered in this project are:

·Anogramma leptophylla (L.) Link (annual fern) (Adiantaceae)—rare on dry rock outcrops in forest in semi-arid areas of the State;

·Asplenium hookerianum Colenso (Aspleniaceae)—rare in wet gullies with three disjunct locations across the State;

·Asplenium trichomanes L. subsp. trichomanes (maidenhair spleenwort) (Aspleniaceae)—localised on dry rock outcrops in forest in the Fingal Valley;

·Blechnum cartilagineum Swartz (gristle fern) (Blechnaceae)—a rare creekside fern in dry forests;

·Cheilanthes distans (R. Br.) Mett. (bristly cloak fern) (Adiantaceae)—rare and localised on dry rock outcrops in dry forests in the east of the State;

·Cyathea cunninghamii Hook. f. (slender treefern) (Cyatheaceae)—rare in wet gullies from widely scattered locations around the Tasmanian coastline;

·Doodia caudata (Cav.) R. Br. (small rasp fern) (Blechnaceae)—rare and localised in riverine habitats in the central north of the State;

·Hypolepis distans Hook. (Dennstaedtiaceae)—rare in wet forests in the north-west of the State and King Island; and

·Pneumatopteris pennigera (Forst. f.) Holttum (lime fern) (Thelypteridaceae)— rare in wet forests in the northwest of the State and on King Island.

Scientific nomenclature and common names follow Buchanan (1995) and Garrett (1996). For convenience throughout most of the text, and only where the information will not be misleading, all taxa, including the subspecies of Asplenium trichomanes, are referred to as 'species'.

Method

Where available, information relating to distributional and ecological data on the nine target fern species (or associated species) was collated from the literature. Specimens of the target species held at the Tasmanian Herbarium, Hobart, the National Herbarium of Victoria, Melbourne, the National Herbarium of New South Wales, Sydney, and at the herbarium of the Queen Victoria Museum and Art Gallery, Launceston, were examined. Relevant data, together with information gathered during the preparation of an atlas of Tasmanian ferns (Garrett 1996), were used to:

· determine attributes of known extant populations; and

· attempt to locate previously unknown populations of the nine fern species.

During the field study phase of the project, data were gathered on each species' distribution (both within the State and within each population), numbers of populations and numbers of individuals within each population, and health of population and whether it is in decline or otherwise. In addition, observations were also made on each species' ecology, including habitat and associated forest type, as well as any observations on each species' biology and natural regeneration that may assist in determining strategies for their long-term survival. Any impacts or outside influences on each species' population was also recorded.

These data, along with any known information on the history of the species since European settlement in Tasmania, were used to prepare management guidelines for each species, and to reassess their conservation and reservation status.

Results and Discussion

3.1 Anogramma leptophylla

3.2 Asplenium hookerianum

3.3 Asplenium trichomanes subsp. Trichomanes

3.4 Blechnum cartilagineum

3.5 Cheilanthes distans

3.6 Cyathea cunninghamii

3.7 Doodia caudata

3.8 Hypolepis distans

3.9 Pneumatopteris pennigera

Presented here are the results of literature and herbaria searches and observations on the target species during field studies. These findings have led to a redetermination of the species' conservation status and a determination of perceived management strategies.

3.1 Anogramma leptophylla

Ecology

In Tasmania, A. leptophylla grows in shallow soil layers over rock, on exposed or semi-exposed outcrops in dry sclerophyll forest, in areas of low to moderate rainfall between 60 m and 300 m a.s.l. Plants are mostly always found on rock ledges, often on, or just inside, the dripline of the overhead rock-face. Asplenium flabellifolium, Cheilanthes austrotenuifolia, various herbs and grasses, and mosses and liverworts frequently grow alongside A. leptophylla. Generally, the species is found in habitats suitable to dry rock outcrop fern species (see Garrett 1995), but is nowhere near as common as those species. In Victoria where the fern is more common, A. leptophylla is reported as also growing in sheltered, damp places such as hollow logs and shaded stream banks.

History

Anogramma leptophylla was first collected at Macquarie Plains in 1840. In 1874 the fern was collected at Spring Bay on the River Tamar. In the same year, and in 1876 and 1879, it was collected from Cataract Gorge at Launceston. (Mary Cameron collected A. leptophylla from the Gorge as recently as 1984, but searches by other workers in recent times, including in the course of this project, failed to find the fern at this locality.) Leonard Rodway collected the species at Glenorchy, possibly in the 1890's or later. Rodway (1903) also recorded it (as Gymnogramme leptophylla Desv.) from Back River [near New Norfolk] and at Georges Bay. In addition, there are several unannotated but obviously early herbarium collections of the fern from Tasmania.

Only in the last 20 years has the fern been found again—at Glenorchy (most likely from the same site as the Rodway collection) and at Sensation Gorge.

Present known distribution

Anogramma leptophylla has a disjunct distribution across Tasmania, being known from Glenorchy near Hobart, at Spring Bay on the River Tamar, and at Sensation Gorge near Mole Creek. It extends to Victoria, New South Wales, South Australia and Western Australia, and is then virtually cosmopolitan in distribution. Morphological studies and caryological analyses have left little doubt that this worldwide species belongs to the one taxon (e.g. see Rasbach & Reichstein 1990; Lovis et al. 1993).

Population descriptions

Anogramma leptophylla is known from three sites in Tasmania, where land tenure is National Park or privately owned. A total of five populations occur at the three sites, but numbers of plants are low, ranging from between 20 and 40 per site.

At all sites where A. leptophylla is still extant, the species is very rare. This is despite the fact that at all sites there are numerous seemingly suitable microsites, but these are all left unoccupied by the fern. In addition, there are numerous sites Statewide that have seemingly identical environmental conditions to the few known locations for the species, yet the fern is absent.

For a plant that is today so rare, the number of early A. leptophylla collections compared to that of other equally rare fern species is extraordinarily high. A few factors may explain this apparent anomaly. Firstly, being a species of cosmopolitan distribution, early collectors may have been familiar with the fern as a native of their country of origin, and may have been eager to collect it. But A. leptophylla was not collected from the British Isles until 1852, and then only from the Channel Islands (Step 1922). As most early collectors were British migrants, this may eliminate this possibility. Secondly, early collectors were usually well acquainted with owners of large grazing properties (e.g. see Buchanan 1988) and perhaps the flora on rock outcrops in their immediate vicinity (e.g. Spring Bay or Macquarie Plains) was relatively over-collected. This possibility requires that the species was then much more common, which is the third scenario.

Adverse impacts

Populations of the species at Macquarie Plains, Back River and Georges Bay, and possibly also at Cataract Gorge, are now presumed extinct. Land clearance for agriculture (and suburban development later) adjacent to populations of A. leptophylla, resulting in loss of habitat due to competition from exotic weeds, has been the major impact on the species. Introduced pasture and garden species as well as the inevitable associated exotic weed species are all abundant at existing A. leptophylla sites as well as at sites where the species is thought extinct. By virtue of its habitat, land clearance alone has not impacted on the species.

Anogramma leptophylla has been known from Cataract Gorge since 1874 and searches by several knowledgeable fieldworkers approximately 100 years later failed to locate the species at that site. In 1984 several plants were found there (M. Cameron pers. comm.), but these could not be relocated in 1996. Exotic trees, shrubs and groundcover plants far outnumber native plants at that location. Anogramma leptophylla was collected at Macquarie Plains in 1840. Recent searches of that area revealed sites that would once have been possible habitats

for the fern, but are now heavily infested with weeds, both herbaceous and shrubby (in particular, Rosa rubiginosa).

Threats to present populations

Anogramma leptophylla is an extremely small and delicate fern, and the deciduous nature of its sporophyte combined with the fragile nature of its 'rootstock', renders the plant as being very susceptible to changes in its immediate environment. Competition from other plants, both native and introduced, would appear to be the species' major threat, resulting in either excessive shading, deprivation of soil moisture and nutrients, or smothering of the rootstock and the consequent suppression of the sporophyte. Thallose liverworts, however, are a regular companion to A. leptophylla both here and at other Tasmanian sites, as well as in New Zealand (Brownsey & Smith-Dodsworth 1989) at least, and their carpeting formation would not appear to have any impact on the fern.

Conservation and reservation status

Anogramma leptophylla has been rated as rare (r2) in Tasmania (FAC 1994). In light of information presented in this report, it is recommended that on a State-level, the status of the species be upgraded to endangered. Anogramma leptophylla is reserved within Mole Creek Karst National Park.

Management

The marginally largest known population is securely reserved within the Mole Creek Karst National Park. This site has also the largest buffer zone of natural bush surrounding it, and as a consequence has the least weed problem. Reservation of any of the sites will not of course exempt them from wind-blown weed seed introduction from outside areas.

Land managers of sites with other tenures should be notified of the existence of the species on their land. As well as the Glenorchy City Council, this should also apply to the Launceston City Council, landowners of Cataract Gorge. Anogramma leptophylla may yet be proved to be still extant at Cataract Gorge and the Council should be made aware of its habitat there as walking track reconstruction around the side of the gorge may impact on the species' habitat.

Hand-pulling of weeds is not an option. The fern's above-ground parts, and especially its unknown reserve of below-ground parts, are too delicate for such a procedure. In addition, the disturbed soil would then create an ideal substrate for weed seed germination. Very selective spraying or application of herbicides with a wick-wiping technique may have to be considered.

3.2 Asplenium hookerianum

Ecology

In Tasmania, A. hookerianum grows in moist, well-drained loamy soils on watercourse margins in rainforest or in very sheltered gullies within drier forest

types, in areas of moderate to high rainfall, from 80 m to 400 m a.s.l. Plants typically grow on vertical or near-vertical banks, often on the lips of ground fissures or sinuses. However, the species does occasionally grow on rock and on the lower trunks (virtually at ground-level) of Dicksonia antarctica and several tree species.

History

Asplenium hookerianum was not known from Tasmania until 1979, when it was collected at Hellyer Gorge. In 1992 the species was collected at Drys Bluff, and in the following year at a site near Orford.


Asplenium hookerianum has a disjunct distribution across Tasmania, being known from Hellyer Gorge in the north-west, Drys Bluff in the central north, and from near Orford in the east. Outside Tasmania, the species occurs in Victoria and New South Wales (Duncan & Isaac 1986) where it is rare, and in New Zealand, where it is one of the most common and widespread species of Asplenium (Brownsey 1977).


Asplenium hookerianum is known from three sites in Tasmania, where land tenure is State Reserve, Forest reserve or privately owned. One population of the species occurs at each of the sites. Between 100 and 200 plants occur in Hellyer Gorge State Reserve, approximately 390 plants occur in Drys Bluff Forest Reserve, and ten plants occur at the site near Orford.

Recruitment at all sites is high, but the comparatively small number of plants at the Orford site (including only two adult plants) may at first appear to be cause for alarm. However, the vegetation at the site is indicative of the flora found in sheltered, dry gullies within dry sclerophyll forest. This would appear to discount speculation that this is a relict population of A. hookerianum, and is more likely the chance result of blown-in spores settling and germinating in a suitable microhabitat.

Adverse impacts

All populations of A. hookerianum are only relatively recently known, and there are no signs of adverse impacts on the species since European settlement.

Casual observations at the Orford site in 1993 compared to those of this survey indicate a decline in numbers of mature individuals at the site. One of the existing adult plants has been half buried by soil and debris knocked loose from an upslope animal pad (most probably wombat). Two juvenile plants grow with this adult plant, and it is uncertain if, or how many, plants have been completely buried.

At the Drys Bluff site, the forest on the western edge of the creek (outside of the Reserve) has been logged in only the last few years. These logging operations have stayed clear of the creek margin, and an ample buffer zone exists between the section of creek containing A. hookerianum and the logged area. There have been no detrimental effects to the A. hookerianum population from this recent logging. Bush adjacent to the creek has been previously logged much earlier however, and the creek is very 'messy' from fallen trees. Some steep slopes of the creek are bare and can be very unstable, and it is unknown what damage might

or might not have occurred to the fern's population when the site was originally logged.


The second adult plant at the Orford site has not been affected by animal-initiated falling debris, but its roots are exposed and the plant is hanging loose. It occurs near water-level (when flowing) and would appear in eminent danger of being lost during flooding.

At the Hellyer Gorge site there are formed walking tracks leading for short distances both upstream and downstream from the picnic area near the bridge. These have not impeded on, nor do they present any danger to existing plants of A. hookerianum. A 4WD track leads to a fishing spot on the banks of the river. Activities of fishers would not appear to present any threat to existing plants. Blackberries are a potential threat however. Seedlings and young plants of this invasive weed are frequent on the banks of the river. More severe infestations appear to have been successfully eradicated from bushland near the picnic area after spraying with a selective herbicide in 1993 in a joint effort of the Parks and Wildlife Service, the Rainforest Conservation Program, and the Department of Roads and Transport. It is not known whether blackberries would encroach into the very dark and moist habitat of A. hookerianum.

Reservation and conservation status

Asplenium hookerianum is rated as vulnerable in Australia (ANZECC 1993) and has previously been rated as vulnerable in Tasmania (FAC 1994). In light of information presented in this report, consideration should be given to the species' rating being downlisted to rare Nationally, and to rare (r2) on a State-level. The two largest known populations of the species in Tasmania are reserved within Hellyer Gorge State Reserve and Drys Bluff Forest Reserve.

Management

Little action is necessary for the continued survival of the species in Tasmania. Already the two largest of the three known populations are well reserved and are with no obvious threats. However blackberry intrusion into A. hookerianum habitats at Hellyer Gorge should be monitored.

3.3 Asplenium trichomanes subsp. Trichomanes

Ecology

In Tasmania, A. trichomanes subsp. trichomanes grows on exposed dolerite outcrops in dry sclerophyll forest in areas of low rainfall at between 450 m and 680 m a.s.l. Plants grow on north-facing outcrops in the shallow soil of crevices or sloping rock platforms. The fern grows only on weathered, sloping rock platforms where numerous grasses, herbs and small shrubs grow in shallow soil layers, and has not been found on the more common columnar dolerite outcrops that contain conspicuously less plant life.

History

Cytological analysis of A. trichomanes from Mt. Durham in 1994 confirmed its ploidy level and consequently its status as subspecies trichomanes. The plant had been known from Mt. Durham, and at the same time suspected as being diploid, from at least as early as 1989. In 1992 it was discovered at Valley Road on Fingal

Tier, and during the course of this project (1996) the subspecies was found also on Huntsmans Cap.


Asplenium trichomanes subsp. trichomanes is localised in the north-east of the State only, at Mt. Durham (two sites), Huntsmans Cap, and at Valley Road below Spion Kop on Fingal Tier. In mainland Australia it occurs in Victoria where it is more common than in Tasmania, and in New South Wales where it is rare. From there it has isolated occurrences in Indonesia, then extends to parts of Asia, Europe and North America. It is not known from New Zealand (J. Lovis pers. comm.).


Asplenium trichomanes subsp. trichomanes is known from three sites in Tasmania, all of which are in State forest. One population of the subspecies occurs at each of the sites, and plant numbers range from 14 at the Valley Road site, approximately 30 and 46 at the Huntsmans Cap and upper Mt. Durham sites respectively, to approximately 139 at the lower Mt. Durham site. Very few sporelings or juvenile plants were observed, but they may have been hidden in crevices on some of the more inaccessible sections of outcrops.

Adverse impacts

All populations of Asplenium trichomanes subsp. trichomanes are only relatively recently known, and there are no definite signs of adverse impacts on the species since European settlement.

The base of the rock outcrop containing the lower Mt. Durham population lies only slightly more than 10 metres from the boundary road of a mature Pinus radiata plantation. The area between was obviously disturbed during the initial land clearance, but the outcrop and its flora appear unscathed. Exposure caused from the land clearance would have had little impact on the naturally sun-loving species, and the mature plantation is at enough distance so as not to cause excess shading.

The population of A. trichomanes subsp. trichomanes at the Valley Road site occurs near the face of a disused quarry. As the fern was not discovered at the site until after quarrying operations had ceased, it is not known whether any plants were lost to quarrying activities. Although there are no supporting data, during the course of the researcher visiting the site since the species' discovery in 1992, there appears to be a decline in plant numbers. Quarrying operations may have over-exposed the site, and plants may have been lost since during periods of drought.


By virtue of the habitat of the known populations, there is little perceived threat to the subspecies. This perception is conditional on the Valley Road quarry remaining closed and that due care is taken during Pinus radiata harvesting at the lower Mt. Durham site.

Conservation and reservation status

Asplenium trichomanes subsp. trichomanes has not previously been listed Nationally or on a State-level. This report recommends that on a State-level the subspecies be rated as rare (r1). Consideration should also be given to a National listing as it is not known from many localities in mainland Australia (J. Lovis pers. comm.). The subspecies is not known to be reserved in Tasmania.

Management

The lower and upper Mt. Durham populations occurring close together in State forest should both be reserved in the one parcel of land. Re-opening of the Valley Road quarry should be disallowed. The lower Mt. Durham site contains the largest number of plants, and due care should be taken during harvesting and replanting of the adjacent Pinus radiata plantation.

3.4 Blechnum cartilagineum

Ecology

Blechnum cartilagineum grows in the deep, well-drained loamy soils of alluvial flats and on the middle slopes of fern gullies, in dry sclerophyll forest in areas of moderate rainfall, below 200 m a.s.l. Plants are usually found in quite open positions, for example, they often grow with the hardy ferns, Calochlaena dubia and Pteridium esculentum.

History

Blechnum cartilagineum was collected from Georges Bay in 1882 and again in 1893. In 1930 it was collected from Glengarry. After quite intensive searching, the species is now presumed extinct at this and the previous location. (Several small and unhealthy plants of B. cartilagineum were found in the 1980's on a disused vehicular track beside Constable Creek, St Helens (D. Ziegeler pers. comm.), but it is suspected that these have since died.) In 1981 B. cartilagineum was collected from Tin Hut Creek, west of Ansons Bay, but the site has since been clearfelled and repeated searching has failed to relocate the species. In 1984 the species was discovered at Little Beach Creek on the east coast, and in 1990 a small colony was found within Ferndene State Reserve. Another much larger population was found at a new site in the Little Beach Creek locality in 1993, and in 1995 it was discovered several kilometres to the north at Tin Creek.


Blechnum cartilagineum is known from Little Beach Creek (two sites) and Tin Creek on the east coast, and from Ferndene State Reserve on the central north coast. The species is endemic to Australia (B. Parris pers. comm.), being found in Victoria, New South Wales and Queensland, where it is more common than in Tasmania.


Blechnum cartilagineum is known from four sites in Tasmania, where land tenure is State Reserve, State forest or privately owned. One population of the species occurs at each of the sites. Numbers of plants range from approximately 180 at Ferndene State Reserve to an estimated 24 000 at the upper Little Beach Creek site.

However these figures are very liberal indeed and are free for interpretation. Blechnum cartilagineum readily reproduces vegetatively by way of underground stolons, and it is uncertain as to what constitutes an individual plant in the species. Furthermore, during this study and in the few years of visiting the upper Little Beach Creek site since its discovery, no fertile plants, sporelings, or young (and obviously spore-grown) plants have been found. This means that, at one extreme, there is the possibility that genetically there is only one plant at the site.

Plants do not appear to produce spores until full-size, an observation that is in need of verification, as plants in Tasmanian populations of B. cartilagineum are uncommonly to rarely fertile. (Fronds are persistent on the plant for at least twelve months, so at any one given time, any fertile frond produced over that period of time is observable on the plant.) The same situation is apparent in Victorian populations of the species (R. Edwards pers. comm.; L. Knolls pers. comm.). No sporelings or young and obviously spore-grown plants were sighted at any of the population sites during the study. Spores from Tasmanian plants are viable as the researcher has raised B. cartilagineum from spores on several occasions.

Adverse impacts

Populations of B. cartilagineum at Georges Bay, Glengarry and at Tin Hut Creek are now presumed extinct due to loss of habitat through logging and land clearance for agriculture, and possibly through mining activities and/or municipal housing.

There has been some decline in the population of B. cartilagineum at the lower Little Beach Creek site. Several disjunct plants further downstream were destroyed in the 1980's during the construction of the Chain of Lagoons – Four Mile Creek link road.

All vegetation at the Tin Creek site has either been clear-felled and burnt, selectively logged or cleared to pasture. The population was not discovered until well after these activities had taken place, and it is not known what the original range and coverage of the species was at the site. The species is now known as approximately 20 discrete colonies scattered along 15 000 metres of the creek's length. Plants are healthiest in areas of selective logging and the largest colony at the site (50 m x 20 m) is still extant (albeit under stress, see Threats to present populations) where the site was clear-felled. Logging may have impacted on the fern elsewhere on the site, but as it is such a hardy, sun-loving species with a strong rootstock (Duncan & Isaac 1986; Garrett 1996), this impact may have been minimal. Where land has been cleared to pasture, several patches of B. cartilagineum are surviving in situ under remnant creekside vegetation or in bulldozed rubble beside the creek. The area of land cleared to pasture beside the creek consists partly of a large alluvial flat in a moist depression. Considering that some plants of B. cartilagineum are still surviving in such a relatively hostile environment, this part of the site may have once, conceivably, held a very large population of the species.

A recently constructed walking track bisects a small colony (the total population at the site) of B. cartilagineum at Ferndene State Reserve, and it is estimated that

between one-fifth and one-quarter of the original population has been lost. Except for some plants which were damaged during track construction, and others that are lacking vigour on the higher (and drier) side of the track, all plants of B. cartilagineum are healthy, and no dead or dying plants were observed.


The majority of the Tin Creek population of B. cartilagineum is on coastal, relatively flat, privately owned land in an area of potentially high commercial and residential development. Blechnum cartilagineum is one of the few naturally rare forest ferns whose normal habitat is in terrain suitable for development. Further upstream in an area not so threatened by development is the largest colony of the species at the site. It occurs in regenerating forest that has previously been clear-felled then burnt. Part of the colony is quite healthy where it is relatively exposed, but a considerable part is heavily shaded under thick Olearia lirata regrowth, and here ferns are dead, dying or stressed.

In horticulture, B. cartilagineum is one of the better known of the rarer fern species in Tasmania, and there is always the danger of pilfering. Ferndene State Reserve is in a well-populated part of the State, it is the only known location for B. cartilagineum except for on the relatively remote east coast, and the fern is easily accessible beside a walking track only a short distance from a frequently empty carpark.

The creekside environment at the lower Little Beach Creek site is a dynamic one. The Mt Elephant area is subjected to short periods of excessively heavy rainfall and the aftermath of flash-flooding in the creek at the site is quite apparent. The course of the creek is in a state of constant change and over a period of time there is alternating deposition on, and scouring of, creekside flats. Thus the growing conditions for creekside inhabitants is also constantly changing. It is not known whether logging activities in the catchment area has exacerbated the process.


Blechnum cartilagineum is rated as vulnerable in Tasmania (FAC 1994). This report recommends that the listing is appropriate. It is only known to be reserved within Ferndene State Reserve.

Management

Presently, the sole Tasmanian reserve known to contain B. cartilagineum is Ferndene State Reserve. The smallest of the known populations of the species occurs in the reserve, and furthermore, is in a somewhat parlous position beside a walking track. By far the largest known extant population of B. cartilagineum occurs in State forest at Little Beach Creek. The rare treeferns, Cyathea cunninghamii and C. marcescens, also occur at the site. The site is very steep and unsuitable for timber harvesting, and should be reserved, either alone or jointly with the nearby existing Lower Marsh Creek Forest Reserve. There is still the doubt surrounding the B. cartilagineum population at the upper Little Beach site as to whether it is sexually reproducing. This trait should be monitored.

The Break O'Day Council should be notified of the fern's existence at the Tin Creek site so the information can be used when vetting applications for development in the area. In what would seem an unnatural strategy for plants

that are normally considered as shade-loving, regrowth of Olearia lirata at the upper section of the Tin Creek site should be slashed or thinned to halt the death of B. cartilagineum through over-shading.

Low-key monitoring of the small B. cartilagineum population at Ferndene State Reserve should be carried out in regard to pilfering, and the walking track re-routed if necessary.

3.5 Cheilanthes distans

Ecology

Cheilanthes distans grows in the shallow soils of ledges on exposed rock outcrops in dry sclerophyll forest, in areas of low rainfall and between 100 m and 350 m a.s.l. All Tasmanian plants have been observed on dry dolerite outcrops with a northerly aspect, and are often associated with both other Tasmanian species of the genus as well as Asplenium flabellifolium, Pellaea calidirupium and Pleurosorus rutifolius. The mainland Australian habitat of C. distans is concentrated in moderately wooded and mountainous districts along the Great Dividing Range, suggesting the species is not adapted to extremely arid conditions (Quirk et al. 1983).

History

Cheilanthes distans was not known from Tasmania until 1993 when it was discovered near Royal George. Later in the same year it was discovered from within the Douglas–Apsley National Park.


Cheilanthes distans is known only from near Royal George and from within the Douglas–Apsley National Park, both in eastern Tasmania. It is common along the east coast of Australia to mid-northern Queensland and with isolated occurrences in South Australia and Western Australia. The species also occurs in both Islands of New Zealand, in New Caledonia, and on Lord Howe Island and Norfolk Island (Quirk et al. 1983).


Cheilanthes distans is known from two sites in Tasmania, where land tenure is National Park or privately owned. One population of the species occurs at each of the sites. Between one and 1 200 plants occur in the Douglas–Apsley National Park, and between 6 and 1 000 plants at the Royal George site.

The wide range of figures for each site is due to the uncertainty of what constitutes an individual plant in the species. It is not clear whether one tuft of fronds represents one plant (represented by the larger of the two figures), or whether all tufts are extensions of rhizomatous growth from one point of origin (and represented by the smaller figure). Tasmanian populations of the species nearly all consist of equal-sized plants in dense colonies, rather than as individuals or small groups. For example, the larger Douglas–Apsley population of 1 200 'plants' grows in an area of only 4 m². This is in contrast to the usual habit of the two other species of Cheilanthes in Tasmania, and gives the appearance of plants having spread from rhizomes. Population and plant numbers of the species in Tasmania are too small to risk any investigative disturbance. Plants are found

growing in spatially limited areas and under exposed and quite windy conditions, a result that does not fit the scenario of germination of air-borne spores.

Adverse impacts

There are no signs of decline to either the Douglas–Apsley National Park or the Royal George populations of C. distans.


There are no obvious threats to either the Douglas–Apsley National Park or the Royal George populations of C. distans. The habitats of both populations are on large and isolated dry rock outcrops. The outcrop at Royal George is surrounded by grazing sheep, and rabbits abound in the area. Cheilanthes distans microsites are inaccessible to these animals, and besides, the species is suspected of being toxic to stock (Everist 1974). Rock outcrops at both sites are surrounded by dry bush, but in the event of fire, the fern's microsite is isolated from such impact (see Garrett 1995 for further discussion of this and related matters).

The modest spatial size of both populations, however, may render them susceptible to other stochastic events.


Cheilanthes distans has previously been rated as endangered on a State-level (FAC 1994). This report recommends the species be downlisted to vulnerable. The species is reserved within the Douglas–Apsley National Park.

Management

Both known populations of the species in Tasmania should be managed passively. The private land owner of the Royal George site has been notified and is aware of the fern's existence on his property. It is highly probable that this diminutive fern has gone unnoticed elsewhere in Tasmania and it may grow at such places as Fingal Tier.

3.6 Cyathea cunninghamii

Ecology

In Tasmania, C. cunninghamii typically grows beside creeks in deep sheltered gullies in areas of moderate rainfall and between 20 m and 250 m a.s.l. Excepting a solitary specimen beside the Pieman River which is at a distance of 40 km from the sea, and the Hastings population which is at a distance of 7 km, all known extant plants of the species occur no more than 3 km from the coast. Cyathea cunninghamii mostly occurs in gullies where the vegetation is wet sclerophyll forest or mixed forest, but with the surrounding hillside vegetation sometimes dry sclerophyll forest (and often only several metres upslope). Plants grow in soil usually no more than several metres from a watercourse and are often in previously disturbed microsites—the spores having required fresh soil for germination.

History

Cyathea cunninghamii has been comparatively well-collected from Tasmania during the past one hundred-plus years. This may be partly due to the impressive stature of the fern, and/or because of its possible former local abundance in some areas of the State.

In 1881 C. cunninghamii was collected from 'Macquarie Harbour' and from 'Long Bay, D'Entrecasteaux Channel', and in 1882 from 'Table Cape'. In 1893 it was collected from 'near Circular Head'. There are several other undated collections from 'Circular Head' as well as one from 'Rocky Cape', all of which may have been from the late nineteenth century. In about 1905 the species was collected from 'Stanley', and there is a photograph taken by J.W. Beattie in or before 1908 of a group of plants at 'Geeveston'.

The species was collected in 1940 from 'east of Brittons Swamp' [NW Tasmania], and in 1946 from 'Smithton'. Wes Beckett, now retired, was a forester in the Smithton district for some fifty years, and has recollections of seeing no more than several dozen plants of C. cunninghamii in the period 1930's to 1970's. All were north of the Arthur River in the Trowutta, Christmas Hills and Togari districts, and occurred as individuals or small groups of plants in untouched forest near areas of selective logging (W. Beckett pers. comm.). The last record of the species in the Smithton district was in 1975 when several plants were discovered during post-logging surveys. These plants have since died from exposure.

Cyathea cunninghamii was collected from 'Eaglehawk Neck' on several occasions during the period 1943-1961, but must have been known earlier from that area as it was recorded there by Rodway (1903). Several plants were discovered at Deep Glen Creek on Forestier Peninsula in 1984, and a solitary plant was found at Bivouac Creek on Tasman Peninsula several years later (M. Neyland pers. comm.).

In 1975 it was collected from Hastings, and in 1982 a large stand of the species was discovered at Lower Marsh Creek on the east coast (D. Ziegeler pers. comm.). During the first half of the 1990's C. cunninghamii was collected at Grassy River (1990) on King Island, at Dalco Creek (1991) in the south-east, at Little Beach Creek (1993) on the east coast, and at Rheuben Creek and Cypress Creek (1994) on the west coast.

The King Island population is rather enigmatic in that when it was discovered in 1990, it consisted of only five plants, all of which were juvenile. The largest plant had a trunk just over 2 m tall, two plants had five centimetre-tall trunks, while two were sporelings with no trunks at all. Cyathea cunninghamii is not mature till it attains a trunk height of 7–8 m. Four plants of C. marcescens Wakefield (see Population descriptions) were also present at the site in 1990—three with one metre-tall trunks and one with a five metre-tall trunk, and all were juvenile. Each of the tallest plants of C. cunninghamii and C. marcescens represented an estimated age of 10 years and 30 years respectively (Garrett, unpubl. data), while the sporeling plants of C. cunninghamii would have been no more than 5 years old. No standing or fallen dead trunks representing the spore source could be located in the vicinity. It is highly possible that fertile plants exist elsewhere in the Grassy River system, and that these are the spore source. Given that there were nine plants in close proximity with such a wide range of ages, it is far less likely that the plants were as a result of wind-borne spore from the Otways in Victoria or from mainland Tasmania. The site has since been devastated by falling trees following storms, and when the site was revisited in 1996, no living plants of C. cunninghamii could be found and only the tallest C. marcescens specimen had survived (and was now 'fertile').

Tall, slender treeferns (called 'cypress treefern' by the bushworkers) were known from the vicinity of Cypress Creek and Rheuben Creek at least as early as 1915, when they were seen during track construction (Conder 1915). The circumstances surrounding the discovery of the single specimen of C. cunninghamii beside the Pieman River near Corinna are not known.

Distribution

Cyathea cunninghamii is presently known from ten disjunct locations in Tasmania. These are, Little Beach Creek and Lower Marsh Creek on the east coast, Deep Glen Creek, Eaglehawk Neck, Bivouac Creek, Dalco Creek and Hastings in the south-east, and Rheuben Creek, Cypress Creek and Pieman River in the west of the State. It is also highly likely that the species is still extant in King Island. Cyathea cunninghamii extends to Victoria where it is rare (Gullan et al. 1990), to New South Wales where several plants only have been found near the Victorian border, and into Lamington National Park in south-eastern Queensland (Andrews 1990). It has a scattered distribution in New Zealand, but can be locally common in both the North and South Islands (Brownsey & Smith-Dodsworth 1989).


Cyathea cunninghamii is known from ten sites in Tasmania, where land tenure is State Reserve, Forest Reserve, Conservation Area or State forest. The three largest colonies with the healthiest plants and the most regeneration are at Lower Marsh Creek (60 adult plants, 86 trunked juveniles and numerous sporelings), Dalco Creek (55 trunked plants—adults and juveniles—and numerous trunkless plants and sporelings) and at Rheuben Creek (12 adult plants, 43 trunked juveniles and numerous sporelings). Numbers of plants at other sites are, Hastings 18, Little Beach Creek 16, Cypress Creek 12, Eaglehawk Neck 10, Deep Glen Creek 2, and Bivouac Creek and Pieman River 1 each.

When compared to the growth rates of other Tasmanian species of treeferns, C. cunninghamii is fast growing. Its trunk growth rate averages 30 cm in height annually (Garrett, unpubl. data). Allowing several years for the plant's establishment and for considerably slower growth rates as its trunk reaches its ultimate height, an estimated life span of C. cunninghamii is 75 years. Plants are not fertile till 7–8 m tall (Garrett 1996), at an estimated age of 30 years.

Cyathea cunninghamii and C. australis are the putative parents of the naturally occurring hybrid, C. marcescens. The hybrid grows at the two sites where the parent species are known to occur together (and where there is ongoing recruitment), Lower Marsh Creek and Little Beach Creek. The hybrid also occurs at Grassy River on King Island where the present status of C. cunninghamii is uncertain (see History notes).

Adverse impacts

Cyathea cunninghamii is now presumed extinct at Macquarie Harbour, at Long Bay south of Woodbridge, at Table Cape and Rocky Cape, and in the Circular Head district. The Circular Head district is represented by a number of collections in herbaria, and of records in the literature and by anecdotal evidence—all of which cover a broad geographical range in an area bounded by Togari, Trowutta, Black River, Stanley and Montagu. In addition, some early sightings of C. cunninghamii in the Circular Head district were erroneously recorded as C. medullaris (Forst. f.) Swartz. This is an endemic New Zealand species which superficially resembles C. marcescens. This indicates that the hybrid was present in the district and is a further indication of the past widespread presence of C. cunninghamii.

Cyathea cunninghamii may also be extinct on King Island, and populations of the species may be extinct at Geeveston.

Local extinction of the species in the north-west of the State, at least, has been caused by loss of habitat from timber harvesting and by land clearance for agriculture. The recent loss of plants on King Island has been due to falling trees during storms.

Creekside adult and juvenile plants at Lower Marsh Creek and Little Beach Creek are commonly destroyed during floods. The Mt Elephant area is subjected to short periods of excessively heavy rainfall, occurring at least once a year, and the aftermath of flash-flooding in the two creeks is quite apparent. For example, a flood during 1988 destroyed a very old and multi-crowned specimen of C. marcescens in Lower Marsh Creek, as well as a number of adult plants of C. cunninghamii in both creeks (Garrett 1993). The same flood destroyed one disjunct and fertile plant of C. cunninghamii situated 3 km downstream on private land, and adjacent to the lower Little Beach Creek Blechnum cartilagineum population. A sporeling found in 1993 growing near the decapitated trunk of that plant was lost to flooding two years later.


None of the presently known populations of C. cunninghamii is currently threatened by agricultural or forestry practices.

But the species' own biology is perhaps one of the biggest threats to the survival of populations presently known to contain only one to several plants. Even though a single mature plant releases copious amounts of spores—hundreds of millions of spores annually—only those populations containing relatively large numbers of plants have active recruitment. This may be explained by a few factors. Plants are not fertile until a trunk height of 7–8 m, an estimated age of 30 years. A microsite receiving ample light, and with fresh soil that is not at risk of drying out for the first couple of years at least, is required for successful germination and continued growth of the prothallus and sporeling. These conditions are often promoted by disturbances such as landslides, fallen trees or flooding, such as occurs at Lower Marsh Creek and Little Beach Creek. There is less chance of recruitment where there are fewer mature plants of C. cunninghamii in less dynamic environments such as the Pieman River site and in Deep Glen Creek and Bivouac Creek.

Conversely to the above, flooding is a threat to the survival of plants at Lower Marsh Creek and Little Beach Creek. However, recruitment of the fern at both creeks is high, and it is quite possible that it more than offsets the mortality rate through flood damage. However this statement relies on the assumption that severe periodic flooding of these creeks is natural, and not a recent phenomenon induced by forestry activities in the creek's catchment areas.


Cyathea cunninghamii is listed as rare on a National-level (ANZECC 1993), and as rare (r2) on a State-level (FAC 1994). This report recommends that the present State listing be retained. Cyathea cunninghamii is reserved within the Pieman River State Reserve (one plant only), Hastings Caves State Reserve, Lower Marsh Creek Forest Reserve, Abel Tasman Forest Reserve and the Southwest Conservation Area.

Management

Cyathea cunninghamii and C. marcescens, as well as the rare ground fern, Blechnum cartilagineum, occur in State forest at Little Beach Creek. The site is very steep and unsuitable for timber harvesting, and should be reserved, either alone or jointly with the nearby existing Lower Marsh Creek Forest Reserve. Regardless of whether or not C. cunninghamii is still extant at Grassy River on King Island, the site containing C. marcescens should be reserved for the presence of that taxon alone. The populations of treeferns at Lower Marsh Creek, Little Beach Creek and Grassy River are important and should be monitored as they contain the only known plants of C. marcescens in Tasmania.

The Pieman River site is the last known location for C. cunninghamii in north-west Tasmania—an area where the species was apparently once more common and widespread than anywhere else in the State. The health of the plant at the site should be closely monitored, especially in regard to any adverse impacts from tourist visitation. (Some decline in the plant's health is to be expected from now on due to the plant's age and greater height of crown giving more exposure to the drying effects of sun and wind.) There is an extremely small chance that soil disturbance from track construction near the base of the fern just might provide suitable conditions for germination of spores from the plant. Any such sporelings should be looked for as often as possible. Consideration may have to be given to the introduction of plants to the site that have been propagated and nursery-grown from spores collected in situ.

The large population of C. cunninghamii occurring in State forest at the Dalco Creek site has been protected by Forestry Tasmania with a special 100 m wide streamside reserve (R. Evans pers. comm.). Forest on the southern side of the creek has been previously logged, but, if and when forest on the steep northern side (which has never been logged) is logged, it will be done only as far as the ridgeline (R. Evans pers. comm.). This, in effect, further widens the streamside reserve.

3.7 Doodia caudata

Ecology

In Tasmania, D. caudata is a riparian plant which grows in an area of moderate rainfall below 50 m a.s.l. The fern grows on the exposed margin of mixed forest, where Eucalyptus obliqua, E. delegatensis, Acacia melanoxylon, Nothofagus cunninghamii, Atherosperma moschatum and Pomaderris apetala are the dominant overstorey species. Doodia caudata grows in clayey soil on mossy riverbanks, and occasionally in higher sites where disturbance has created a near-vertical substrate.

History

Doodia caudata was collected from the Launceston area (probably Cataract Gorge) in about 1833. It was collected definitely from Cataract Gorge in 1844, and in 1861 was collected from a limestone cave near the unknown location of Bates Ford (but possibly on the River Leven?). The species was collected from Port Dalrymple in the 1890's, and from Georges Bay in 1891. It was not until the 1980's that the species was again recorded, this time from the River Leven.

Closer examinations of the herbarium specimens referable to the Bates Ford and Georges Bay collections, may yet reveal them to be merely smaller than usual fronds of D. media taken from plants growing under conditions of extreme exposure.


In Tasmania, D. caudata is presently known with certainty only from beside the River Leven. It also occurs in Victoria, New South Wales, Queensland and South Australia, and on Lord Howe Island. In her treatment of the species for the Flora of Australia project, Barbara Parris (pers. comm. 1996) will not be recognising D. caudata outside these areas.


Doodia caudata is presently known only from the one site in Tasmania, on the banks of the River Leven, where riverbank tenure alternates along the length of the river between State forest, Crown land, River Reserve, Sith Cala Nature Reserve and privately owned. One discontinuous population of the fern occurs along approximately 9 km of the river's length. The number of plants is estimated at between 1 000 and 2 000.

Sticherus lobatus, a fern species that is rare in Tasmania and poorly reserved, is abundant in some locations at the site.

Adverse impacts

Doodia caudata is now presumed extinct at Georges Bay, at Port Dalrymple and at Cataract Gorge. The species is known from Georges Bay and Port Dalrymple only by herbarium specimens collected in the 1890's. Both Georges Bay and Port Dalrymple have large expanses of hinterland, and without knowing the exact location of the herbarium collections, it is difficult to even speculate on the reasons for the species' possible extinction in those areas. It can be assumed that plants of D. caudata once existent at Cataract Gorge were truly riparian as are existing plants at River Leven. Changes in water-level (i.e. resulting in either riverbank drought or severe flooding of riverside vegetation) following hydro-electricity developments on the South Esk River for the Duck Reach Power Station in 1895 and again for the Trevallyn Power Station in 1950, may be responsible for the species' demise at Cataract Gorge.

There is a probability that the River Leven population of D. caudata may have been enhanced by the construction of a now-disused railway line in the early 1900's (W. Deacon pers. comm.) along the western bank of the river. The line runs beside the river at several metres above flood-level, and at several places D. caudata has established on cuttings. As the track has been cut into sloping ground in most places, the discarded rubble on its bottom side has created a new riverbank. It is at these sites that most plants of D. caudata are growing. The eastern bank of the river, where there is no such disturbance, is not as easily accessible, but where it can be reached in the Sith Cala Nature Reserve, plants of the species are smaller and not as common.


Blackberries are establishing at numerous places on the banks of the river (water-spread?) and on the old railway cuttings (human/animal/bird-spread?). Currently, this potentially threatening weed mostly occurs as seedlings or young plants, with larger infestations uncommon in areas where D. caudata has been found. But further upstream towards Bannons Park and beyond to Gunns Plains, blackberries (and to a lesser degree, willows) are well-established along large sections of the riverbank. The weed infestations are most serious where privately owned land cleared to pasture, or public roads, flank the riverbank.


Doodia caudata is listed as vulnerable on a State-level (FAC 1994). This report recommends that the listing is appropriate. The species is reserved within the Sith Cala Nature Reserve.

Management

The species is truly riparian in habitat and where it occurs in State forest is well protected within the 40 m wide streamside reserve assigned to the River Leven as a Class 1 watercourse under the Forest Practices Code. However any upstream activities with unfavourable water-borne consequences are possibly just as crucial to the survival of the species as are adjacent land-based activities. If other attributes of conservation value are identified in the area, then consideration should be given to the reservation of the section of the River Leven population of D. caudata occurring in State forest on the western bank of the river, starting 500 m downstream from Dial Creek and continuing at least to 500 m downstream of Hardstaff Creek. This area contains also the rare and poorly reserved fern, Sticherus lobatus.

Hand-pulling of blackberries on the easily accessible railway cuttings should also be considered by perhaps a local landcare, naturalists or walking club group. The railway line has now been cleared to a walking track as part of the Coast to Cradle Mountain Track.

3.8 Hypolepis distans

Ecology

In Tasmania, H. distans has been observed growing in soil or over rotting logs in previously logged wet sclerophyll forest where Acacia melanoxylon is the dominant plant, in areas of moderate rainfall below 40 m a.s.l. On King Island it is reported as usually growing on the margin of swampy ground in organic material at the base of Todea barbara and Restio tetraphyllus under scrub dominated by Melaleuca squarrosa and Leptospermum scoparium (Brownsey & Chinnock 1987). In New Zealand the species is normally associated with swampy areas, growing in peat, humic soils, or on rotting logs (Brownsey & Chinnock 1984).

History

Hypolepis distans was not known from Australia until 1973 when it was collected from south of Pennys Lagoon on King Island. (There is a 1968 collection of the species in the Tasmanian Herbarium from Max McGarvie's fernery, King Island). In 1987 it was first collected from mainland Tasmania at Barcoo Road, and in 1990 it was found growing at Allendale Gardens near Edith Creek. The exact location and present status of a 1994 collection in the Tasmanian Herbarium from 'Salmon River Road, south of Togari' is unknown.


Hypolepis distans is known at Allendale Gardens and at a site beside Barcoo Road, both in extreme north-western Tasmania, and within the Lavinia Nature Reserve on King Island. The species has not been collected from mainland Australia. In New Zealand it is much more common, occurring on both the North and South Islands.


Hypolepis distans is known from three sites in Tasmania, Allendale Gardens (private land), Barcoo Road (Crown land), and Lavinia Nature Reserve on King Island. One population of the species occurs at each of the first two sites, but population and plant numbers are unknown for the King Island site.

At Barcoo Road, ten small and discrete plants as well as a single disjunct plant are present. The Allendale Gardens population is far greater and consists of three scattered patches of plants in a total area of 5 000 m². Hypolepis distans is one of several Tasmanian fern species that spread by means of an extensively creeping rhizome. Estimating plant numbers within a population is comparable to counting plants of Pteridium esculentum (bracken fern). The three patches of ferns contained in the Allendale Gardens population have possibly originated from a single plant, and all 'plants' within each patch are still connected by a network of subterranean rhizomes. Excepting the one disjunct plant, the ten plants at Barcoo Road grow in an area of only 30 m², and it is highly likely that they are the result of a single plant breaking up through injury or natural decay to interconnecting parts of the rhizome.

Adverse impacts

Hypolepis distans was discovered on mainland Tasmania in 1987, from an area of the State where there has been much loss of natural vegetation due to forestry activities and land clearance for agriculture. The species' habitat is in or on the margin of swampy forested areas. Such areas were once abundant in the north-west of the State but have since been extensively drained and the land cleared to pasture. The Allendale Gardens population grows on the margin of a forest only several metres from pasture. Both Barcoo Road and Allendale Gardens populations survive in previously logged forests. In the few years prior to the recent establishment of the nature walk at Allendale Gardens, all ground ferns (presumably including H. distans) at the site were eaten to ground-level by goats (L. Cross, pers. comm.).

Any impacts on the King Island population of Hypolepis distans are unknown. The species was discovered there in 1973 and the area declared a Nature Reserve in 1975.


Currently there are no serious threats to the Allendale Gardens population of H. distans, though blackberries are establishing on some sections of the perimeter of the population, some plants are constantly trampled in a wallaby run, and there is competition from Histiopteris incisa (most likely temporary only) in some places.

The Barcoo Road population of H. distans occurs just inside the roadside fence beside a gravel road, and as with other plants in such situations, is covered in road dust. Blackberries do not yet occur in uncontrollable proportions, but are well established along the fence-line and are intertwined with several of the H. distans plants. On several occasions some of the plants have been observed to be flattened, and the micro-site may be a regular resting place for mammals. There are several dead or dying plants that appear to have been affected by a combination of the above factors. The population occurs in the tightly angled corner of a Crown-owned block, with the road fence as one boundary and with the other side of the other boundary fence being privately owned and used as a

cattle-run. The blackberries, in particular, will become an ever-increasing threat to the remaining plants unless action is taken.

Any threats to the King Island population of Hypolepis distans are unknown.


Hypolepis distans is rated as vulnerable in Tasmania (FAC 1994). The species presently has no National listing, and until its status is determined on King Island, this report recommends the State vulnerable rating be retained and that Nationally it be rated as vulnerable. Hypolepis distans is only known to be reserved within Lavinia Nature Reserve on King Island.

Management

The landowners of the Allendale Gardens site are keen plant-lovers and, at least in the immediate future, are eager and quite capable of monitoring threats to the H. distans population occurring on their property.

Negotiations are underway for a local landcare or conservationist group to alleviate threats to and monitor the Barcoo Road population of H. distans. The population is ideally suited to such management, as it is small, on Crown Land and freely accessible beside a public road, and with easily controllable threats.

3.9 Pneumatopteris pennigera

Ecology

In Tasmania, P. pennigera grows in calcareous, moist and sometimes boggy soil in wet sclerophyll forest or beneath a canopy of Leptospermum and Melaleuca, in areas of moderate rainfall, at or below 45 m a.s.l. Plants typically grow on the banks of rivers and creeks and on alluvial flats.

History

Pneumatopteris pennigera was collected by Leonard Rodway from 'North-west coast in swamp country' in January 1907 and in February of the same year from 'near Duck River'. Both of these collections may or may not refer to present-day locations for the species. Rodway also collected P. pennigera from 'near Mole Creek' possibly at about the same time as the previous two collections, as there was no mention of the species in his The Tasmanian Flora in 1903. The exact location of this collection and the present status of the species at that site are unknown. Copper Creek has been the location for several collections dating from 1948 onwards. In 1966 the species was collected from Ettrick River on King Island, and although the exact year of its discovery from Pass River on King Island is unknown, its presence there was related to the researcher in 1990 (P. Barnett pers. comm.). In the mid-1980's it was discovered near the Arthur River and a second location in the same vicinity was found during the course of this study (1996).


In Tasmania, P. pennigera is known from Ettrick River and Pass River on King Island, and from near Arthur River (two sites) and at Copper Creek in the north-west . Outside Tasmania, the species occurs in Victoria, where it was not discovered until 1943 and is rare (Duncan & Isaac 1986), in south-eastern Queensland (Andrews 1990), and in New Zealand where it is common and

widespread (Brownsey & Smith-Dodsworth 1989). There is some speculation that the New Zealand taxon may be taxonomically distinct from at least the Tasmanian and Victorian taxon (P. Brownsey pers. comm.; B. Duncan pers. comm.).


Pneumatopteris pennigera is known from five sites in Tasmania, where land tenure is Protected Area or privately owned. One population is known from each site. By far the largest population is at Copper Creek, where conservatively, it is estimated there are in excess of 2 500 plants. At this site, the species sometimes occurs in quite large monospecific stands. Thirty-four and 20 plants occur at Arthur River (B) and Ettrick River sites respectively. Populations at Arthur River (A) and Pass River sites are seven and three plants respectively, and are threatened with extinction.

Adverse impacts

The population of P. pennigera at Mole Creek is presumed extinct. There are several low-altitude creek systems in the area that would presumably have once contained habitats suitable for the species. Much of the Mole Creek area has since been cleared to pasture for dairying and nearly all natural creekside vegetation has been destroyed or has been smothered by blackberries.

The population of P. pennigera at the Arthur River (A) site is almost extinct. At the time of this survey, only seven plants were seen. All had tall trunks and more than half were obviously dying. This population was not discovered until the mid-1980's and the site was first visited by the researcher in 1992. Between 20 and 30 living plants were seen then, but dead trunks were also present, and it was obvious that the population was in a state of decline. Several younger or juvenile plants were noted then as being present on the drier soak perimeter, and adventitious growth was quite common on trunks of living plants. The population also extended for a greater area than the present remnant population. There are no obvious outside influences that would seem responsible for the decline of P. pennigera at this site. Patrick Brownsey (pers. comm.) has not seen anything comparable in New Zealand populations of the species. Although plants at this site are unhealthy, their fronds show no signs of attack by pathogens, which has been the reason for decline in some Victorian plants (see Cropper 1993).

It is important to note the presence of mostly very old, even-aged plants and the almost complete absence of recruitment at this site. If trunk length can be used as a guide to plant age, then these plants are much older than any other plants of the species seen in Tasmania. Is it possible that conditions were right for a sudden influx of spores to germinate and the resulting colony behave as temporary coloniser? Or have conditions not been suitable for spore germination since? Whatever the reason, the decline would appear to be from natural causes.

The population of P. pennigera at the Pass River, King Island site is also almost extinct. Only three plants are presently known from there, and all are in poor condition, possibly as a result of flood damage. Anecdotal evidence (G. Batey pers. comm.) would indicate that the Pass River population of P. pennigera was once much larger. Some sections of the river would have once been seemingly ideal habitats for the fern, but riverbanks and flats have been dramatically altered. Adjacent land has been cleared to pasture, in some cases right to the riverbank; cattle have accessed the river for a greater part of the river's length (unlike the Ettrick River, King Island site, here there are no topographical barriers

to entry by cattle); weeds are commonplace; and the combined action of soil disturbance by cattle and subsequent flooding has led to seemingly irreparable damage, including riverbank collapse.

The Copper Creek site is a small wide-bottomed gully in the midst of large tracts of flat land cleared to pasture for dairy cattle. A now disused railway line (constructed in 1919 and abandoned in 1963, K. Pink pers. comm.) for timber cartage runs beside the creek. Only several years ago blackberries made sections of the railway (the best access to the site) impenetrable, and this and other weeds such as ivy have encroached on the creek. The severity of the blackberry problem has now diminished somewhat—plants have either succumbed to blackberry rust, have been eaten by goats, or have been sprayed with herbicide. Land adjacent to existing stands of the fern has been cleared to pasture some time ago, and clearance on a smaller scale has occurred from time to time since (including recently), resulting in the loss of plants. Ferns adjacent to cleared areas are stunted from the increased exposure or are being smothered by encroaching weeds. Cattle have impacted on some sections of the creek but areas where the largest stands of the fern occur appear to have been kept cattle-free.

A total of 20 plants of P. pennigera, all growing in the one colony, were observed at the Ettrick River, King Island site during this survey. Approximately six plants of

P. pennigera seen upstream of this site by the researcher in 1992 could not be located during this survey. They grew in soil made boggy by seepage from an uphill calcareous deposit. The slopes of the river valley are quite steep in parts but cattle have access to sections of the river. Trampling and soil disturbance by the cattle combined with periodic flooding of the river has led to severe degradation of sections of the riverbank. Weeds have also taken over in some areas. The only known extant colony of P. pennigera at Ettrick River may be the remnant of a previously much larger population of the species occurring beside the river.


There would seem to be little hope for either the survival or resurrection of both the Arthur River (A) and Pass River, King Island populations of P. pennigera.

Continued trampling by cattle has both the immediate deleterious effects as well as the long-term impact of erosion of habitat when followed by flooding. Soil disturbance by cattle and agricultural practices adjacent to populations of P. pennigera will also continue to exasperate the weed problem. A combination of these factors are presently having an adverse impact on the Copper Creek and Ettrick River, King Island populations. The Copper Creek population is further at risk from occasional small-scale land clearance and from problems associated with the fact that the site occurs at the intersection of three private properties, all with different owners. This very large and significant population is continuing to be eroded away at the edges.

The recently discovered Arthur River (B) population of P. pennigera is the only known population of the species in Tasmania without any signs of decline or any obvious threats.


Pneumatopteris pennigera is rated as rare in Australia (ANZECC 1993) and has previously been rated as vulnerable in Tasmania (FAC 1994). In light of information presented here, this report recommends the species' rating being

uplisted to endangered on a State-level. Pneumatopteris pennigera is known to be reserved only in the Arthur-Pieman Protected Area.

Management

There would seem little hope that any form of management will save the Arthur River (A) population of P. pennigera. There is slightly more hope for the Pass River, King Island population, but it would appear as being more practical to concentrate all efforts on the larger and other King Island population at Ettrick River. The plants at the latter site grow on a steep bank beside the river, and as such, are isolated from the deleterious impacts normally associated with the species. Passive management may be all that is required for this population, and because of its isolation from the mainland, the monitoring of its progress may be an ideal project for a local group.

Management strategies for the very large and very important Copper Creek population are problematic. The site is in the midst of a large tract of privately owned land and the greatest part of the population occurs at the intersection of three properties, all of which have different owners. Ideally, a combination of reservation and management strategies would provide the best outcome for the species. A management strategy without reservation at Copper Creek would require negotiations with landowners to ensure that the P. pennigera population, as well as a suitable sized buffer zone, be protected from further land clearance. The population should then be fenced at places where there is likelihood of cattle encroachment. In other places the narrow but very deep creek itself provides a suitable barrier for unwanted intrusion. A weed-pulling programme should then be initiated at the population perimeter, and then further weed invasion monitored and the programme maintained when and where necessary.

Summary for all target species

4.1 Adverse impacts

4.2 Threats to present populations

4.3 Conservation and reservation status

4.4 Management

4.1 Adverse impacts

Five of the nine target species each have one to several populations that since European settlement are presumed to have become extinct. All are from areas of the State outside the geographic range of existing known populations of their respective species. Extinct populations were predominantly in the north of the State, with three of the species once known from Georges Bay and two species from Cataract Gorge.

With the exception of the Cataract Gorge site, local extinction of fern species at most other sites can be definitely attributed to land clearance for agriculture, and to a lesser degree, timber harvesting. Clearing of land for agriculture and dairying has often led to such severe consequential impacts as invasion by exotic weeds and trampling by livestock. Weed invasion has resulted in loss of fern species' habitats due to competition for growing space, for soil moisture and nutrients, and for light. Trampling by livestock at creekside waterholes has in turn caused soil disturbance and general degradation of sites leading to erosion and loss of habitat during flooding.

Isolated occurrences such as development for hydro-electricity, walking track construction and flooding, are also thought to be responsible for the loss or decline in populations.

It is interesting to note that fire has had little or no impact on rare or threatened forest ferns in Tasmania. As a general rule, Tasmanian species of ferns either grow in habitats isolated from fire, or the structure of their plant parts is such that they are able to recover from such catastrophic events. For example, of the nine target species, Anogramma leptophylla, Asplenium trichomanes subsp. trichomanes and Cheilanthes distans are insulated from the effects of fire due to their rock outcrop habitat; Asplenium hookerianum and Cyathea cunninghamii grow in dark and very moist situations not usually associated with fire; Doodia caudata grows near the high-water mark on river banks and in such situations is usually immune from fire; Pneumatopteris pennigera (and to a lesser degree, Hypolepis distans) grows in very wet and boggy soils where vegetation is not usually susceptible to fire; and while all their top growth may be destroyed by fire, there is a strong recovery of growth from subterranean rhizomes in Blechnum cartilagineum and Hypolepis distans. Growth recovery following fire in the last two species is comparable to that of Blechnum wattsii and Pteridium esculentum respectively. Furthermore, a single disjunct plant of Cyathea marcescens (a naturally occurring hybrid between C. cunninghamii and C. australis) observed in a drier than usual habitat and in previously burnt but regenerating vegetation at Lower Marsh Creek, had a blackened trunk topped with a vigorously growing and healthy crown of fronds.

4.2 Threats to present populations

Future threats to the ferns are seen as mostly from continued clearance of land for agriculture, and from the consequential, and existing, adverse effects of competition from exotic weeds and trampling by stock. In nearly all cases these impacts are not perceived as potentially severe. But in the case of two species, Anogramma leptophylla and Pneumatopteris pennigera, the above-mentioned impacts are known to have in the past extinguished or near-extinguished populations of both, and are presently endangering remaining populations.

Isolated occurrences such as proposed residential development, excess shading from vegetation regrowth, flood damage (possibly naturally induced), and trampling by native mammals, are also perceived as being possible minor threats to existing fern populations.

No species are in situations where forestry activities can definitely be perceived as current or potential threats.

4.3 Conservation and reservation status

The conservation and reservation status of the target species according to their risk codes is summarised in Table 1.

Table 1. Recommended State and National risk codes for rare or threatened Tasmanian forest ferns

taxon risk code *

state national

Anogramma leptophylla e not listed

Asplenium hookerianum r2 R

Asplenium trichomanes subsp. trichomanes r1 u **

Blechnum cartilagineum v not listed

Cheilanthes distans v not listed

Cyathea cunninghamii r2 R

Doodia caudata v not listed

Hypolepis distans v V

Pneumatopteris pennigera e R

* For an explanation of codes see FAC (1994)

** Will probably require National listing when the subspecies' status is fully known in mainland Australia

Bold type indicates recommended additions or changes to existing State (FAC 1994) or National (ANZECC 1993) listings.

4.4 Management

Reservation or improved reservation of some species is seen as a practical, plausible and workable strategy for ameliorating adverse impacts. Recommended sites for reservation for each of four target species fall within areas of State forest, that, because of the surrounding topography, are considered unsuitable for timber harvesting. One of these taxa, Asplenium trichomanes subsp. trichomanes, is presently not known to be reserved in Tasmania, and two, Blechnum cartilagineum and Doodia caudata, are presently poorly reserved. The fourth species, Cyathea cunninghamii, is adequately reserved, but not so the hybrid, C. marcescens. In any case, the proposed site for reservation of C. cunninghamii, Little Beach Creek, happens to be the same proposed site for reservation of B. cartilagineum.

Negotiations with private landowners will be necessary to adequately secure the Grassy River (King Island) Cyathea site and the very important Copper Creek Pneumatopteris pennigera site. Land managers and landowners require notification or confirmation of, as well as information about, the presence of any of the target species on their land. In some cases this requirement has been satisfied during the course of the project.

Some species require an active management programme, sometimes in addition to land reservation. Management prescriptions involve hand-pulling of weeds (and the slight probability of herbicide spraying or wick-wiping), clearing of native vegetation regrowth, and in one case only, fencing. Nearly all procedures require little human or financial resources and are initially short-term actions only that need to be followed up with regular monitoring. As such, all management strategies following the initial negotiations with land managers or private landowners where necessary, are ideally suited to interested local groups. But it is suggested that the monitoring of the success of these procedures, and of the longer term monitoring of the populations for other adverse impacts, be undertaken by officers of the Parks and Wildlife Service. Tourist impact on the lone Cyathea cunninghamii specimen in the Pieman River State Reserve and signs of pilfering from the small colony of Blechnum cartilagineum at Ferndene State Reserve should also be monitored by officers of the Parks and Wildlife Service.

In the case of two species, Asplenium hookerianum and Cheilanthes distans, where additional land reservation is not recommended, passive management only is required. Passive management is all that is required of a third taxon, Asplenium trichomanes subsp. trichomanes, provided the recommendation for its reservation is satisfied.

Nearly all strategies involving active management are concerned with populations occurring on privately owned land or in State Reserves. There is one very small but important strategy for a population on Crown land. There is one case only in State forest, and even then, this strategy only involves weeding, which may yet prove to be unnecessary.

Data gaps and recommendations for further work

Due to the comparative taxonomic stability of Tasmanian representatives of the Pteridophyta, and of the recent intensive research into their distribution (Garrett 1996), the contents of this report are considered a fair assessment of the status of rare or threatened forest ferns in Tasmania. But with this increased knowledge, comes easily identifiable gaps in the available data. In addition, seasonal weather-related conditions underfoot during the course of this project restricted access to several important sites.

This report recommends that future distributional fieldwork be undertaken on the following species in the following places:

Anogramma leptophylla may still be extant at Cataract Gorge and should be searched for between September and December. The abundance of, or absence or presence of, particularly small remnant populations, may vary from year to year;

The full range and exact plant numbers of Asplenium hookerianum at Hellyer Gorge needs to be clarified. Considered to be a true riparian in most cases at the site, the species is best searched for during late summer in periods of low water-level;

Further populations of the diminutive species, Cheilanthes distans, may well occur on Fingal Tier or on other dry, sunny sites near Royal George, and should be searched for;

Cyathea cunninghamii and further specimens of C. marcescens should be searched for in the Grassy River system on King Island;

The full range of Doodia caudata beside the River Leven requires clarification. Being a truly riparian species at the site, the fern is best searched for in late summer during periods of low water-level. The species should also be searched for at high-water mark in Cataract Gorge;

Nothing is known of the extent of, or the number of plants in, the Lavinia Nature Reserve, King Island population of Hypolepis distans. These data are extremely important as this is the only reserved population of the species in Australia, and the only other two known populations are very small. The Lavinia Nature Reserve population occurs in very wet and swampy ground and needs to be visited during the driest possible time in late summer. The exact location and present status of a 1994 collection of H. distans in the Tasmanian Herbarium from 'Salmon River Road, south of Togari' needs to be identified.

There is a requirement for a better knowledge of aspects of the ecology and biology of most species. Uncertainty in some of these subject areas hinders the completion of more detailed management prescriptions. Further studies in the following subject areas or answers to the following questions are desirable:

A continued monitoring of rare or threatened fern species' population attributes is essential. The almost total lack of knowledge of past attributes has rendered declination assessment impossible in most species. The process has commenced with this report;

The life histories of all species; The processes behind the perennation of the gametophyte and their

relationship with the annual sporophyte in Anogramma leptophylla. Do numbers of sporophytes vary greatly from year to year?;

Is the large Blechnum cartilagineum population at the upper Little Beach Creek site fertile, and if so, is there any sexual regeneration?;

What are the effects of flash-flooding on the creekside biota (including Cyathea cunninghamii and C. marcescens) in Lower Marsh Creek and Little

Beach Creek, and in their tributaries and in other creeks in the area? Is this a natural phenomenon or has it been worsened by loss of vegetation from logging or clearing in catchment areas?;

Are plants of Cheilanthes distans in their few, small known populations a result of spore germination or are they produced vegetatively from rhizomes?;

What are the apparently natural reasons for the local decline of Pneumatopteris pennigera at the Arthur River (A) site?

References

Andrews, S.B. 1990, Ferns of Queensland, Dept Primary Industries, Brisbane.

ANZECC Endangered Flora Network 1993, ANZECC List of Threatened Australian Flora, June 1993, Australian Nature Conservation Agency, Canberra.

Brownsey, P.J. 1977, A taxonomic revision of the New Zealand species of Asplenium, New Zealand Journal of Botany 15: 39-86.

Brownsey, P.J. & Chinnock, R.J. 1984, A taxonomic revision of the New Zealand species of Hypolepis, New Zealand Journal of Botany 22: 43-80.

Brownsey, P.J. & Chinnock, R.J. 1987, A taxonomic revision of the Australian species of Hypolepis, Journal of the Adelaide Botanic Gardens 10(1): 1-30.

Brownsey, P.J. & Smith-Dodsworth, J.C. 1989, New Zealand Ferns and Allied Plants, David Bateman, Auckland.

Buchanan, A.M. 1988, The Tasmanian Collecting Localities of Ronald Gunn & Joseph Milligan, Tasmanian Herbarium Occasional Publication No. 1, The Tasmanian Herbarium, Hobart.

Buchanan, A.M. 1995, A Census of the Vascular Plants of Tasmania & Index to 'The Students Flora of Tasmania', Tasmanian Herbarium Occasional Publication No. 5, The Tasmanian Herbarium, Hobart.

Conder, H. 1915, Port Davey to Macquarie Harbour. 100 miles of track, The Mercury, Hobart, 31 March 1915.

Cropper, S.C. 1993, Management of Endangered Plants, CSIRO, East Melbourne, Victoria.

Duncan, B.D. & Isaac, G. 1986, Ferns and Allied Plants of Victoria, Tasmania and South Australia, Melbourne University Press, Carlton, Victoria.

Everist, S.L. 1974, Poisonous Plants of Australia, Angus and Robertson, Sydney.

FAC [Flora Advisory Committee] 1994, Native Higher Plant Taxa which are Rare or Threatened in Tasmania, Parks and Wildlife Service, Hobart.

Garrett, M. 1993, Pteridophyte distribution within Tasmanian forest reserves,Tasforests 5: 25-33.

Garrett, M. 1995, Distribution and ecology of ferns on dry rock outcrops in Tasmania, with special reference to Fingal Tier, Tasforests 7: 77-92.

Garrett, M. 1996, The Ferns of Tasmania. Their Ecology and Distribution, Tasmanian Forest Research Council, Hobart.

Gullan, P.K., Cheal, D.C. & Walsh, N.G. 1990, Rare or Threatened Plants in Victoria, Dept Conservation and Environment, East Melbourne, Victoria.

Lovis, J.D., Rasbach, H. & Reichstein, T. 1993, The chromosome number of Anogramma leptophylla (Adiantaceae: Pteridophyta) from New Zealand and South Africa, Fern Gazette 14: 149-154.

Quirk, H.M., Chambers, T.C. & Regan, M. 1983, The fern genus Cheilanthes in Australia, Australian Journal of Botany 31: 501-553.

Rasbach, H. & Reichstein, T. 1990, The chromosome number of Anogramma leptophylla (Adiantaceae: Pteridophyta) from Europe, Fern Gazette 13: 341-348.

Rodway, L. 1903, The Tasmanian Flora, Govt Printer, Hobart.

Step, E. 1922, Wayside and Woodland Ferns, Frederick Warne & Co., London.

Appendix 1: Personal communications

Mr Paul Barnett, naturalist, Gellibrand River, Victoria (ex King Island).

Mr Graeme Batey, King Island Field Naturalists Club, Yarra Gorge, King Island.

Mr Wes Beckett, retired forester, Smithton.

Dr Patrick Brownsey, Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand.

Mrs Mary Cameron, Queen Victoria Museum and Art Gallery, Launceston.

Mrs Lorraine Cross, proprietor Allendale Gardens, Edith Creek.

Mr Bill Deacon, local historian, Ulverstone.

Mrs Betty Duncan, botanist, Balwyn, Victoria.

Mr Ray Edwards, spore collector and fern propagator, Beech Forest, Victoria.

Mr Rodney Evans, Forestry Tasmania, Geeveston.

Mr Leighton Knolls, spore collector and fern grower, Silvan, Victoria.

Professor John Lovis, Dept Plant and Microbial Sciences, University of Canterbury, Christchurch, New Zealand.

Mr Mark Neyland, Forestry Tasmania, Hobart.

Dr Barbara Parris, Fern Research Foundation, Bay of Islands, New Zealand.

Mr Kerry Pink, local historian and author, Burnie.

Mr David Ziegeler, consultant ecologist, Hobart.

Appendix 2: Project brief

Preparation of recovery plans and management guidelines for threatened ferns and orchids in Tasmanian Forests.

CRA - Endangered Species / Biodiversity

1. TITLE

Preparation of recovery plans and management guidelines for threatened ferns and orchids in Tasmanian Forests.

2. PRINCIPAL INVESTIGATORS

Michael Garrett, private fern expert (referee : Dr M J Brown, phone (002) 338202) and David Ziegeler, private consultant (referee : David Jones, Centre for Plant Biodiversity Research, phone (06) 2465502). Both are acknowledged authorities on these plant groups within the state.

This project will be overseen by Stephen Harris, Senior Botanist, Parks and Wildlife Service in liasion with the CRA Project Team and ANCA.

3. LOCATION OF WORK

All regions of Tasmania will be considered but with a focus on the following IBRA regions within which most of the work will be carried out are : Woolnorth (WOO), Ben Lomond (BEN), Freycinet (FRE), Tasmanian Midlands (TM), D'Entrecasteau (DE) and West and South West (WSW).

4. PROJECT OBJECTIVES

To prepare recovery plans for the nationally listed species to meet the requirements of Sect. 32 of the Commonwealth Endangered Species Protection Act 1992. For state listed threatened species (as well as nationally listed species) management guidelines will be prepared according to the format prepared by Barker (see attachment) for the proposed Management Manual for Threatened Forest Species. The objectives will be aimed at ameliorating adverse effects on the survival of the species.

5. BACKGROUND

The project addresses the conservation requirements of four nationally threatened species. An additional two species (one fern, one orchid) are proposed for national listing. A further eight species are threatened at the state level. All taxa occur in forests. Prasophyllum milfordensis, which is proposed for national listing, occurs in coastal Eucalyptus viminalis forest which is one of the highest priority communities (of the 39 Resources Assessment Commission communities adopted for the I.F.A.) requiring reservation and conservation management. M. Garrett and D. Ziegeler believe that further targeted searching may be productive. Both have compiled atlases but, in dealing with all the taxa in their groups, there was insufficient time to target subsets of species (such as threatened species) for more sustained intense survey.

(i) Ferns

There is one nationally listed fern : Asplenium hookerianum (V) which occurs in riverine forested environments. Only three sites are known, one from Hellyer River, one from Drys Bluff and one from Orford. Pneumatopteris pennigera is presently listed as nationally rare and vulnerable at the state level. This is likely to be put on the list as Endangered because the existing Tasmanian populations (south of the Arthur River and at Copper Creek in NW Tasmania) seem to be affected by dieback. The Victorian populations are equally parlous. Both sites occur in forest. Other ferns occurring in forest and which are threatened at the state level are :

* Blechnum cartilagineum v, north-north east, dry forest.

* Cheilanthes distans e, east coast, dry forest.

* Doodia caudata v, north coast, Leven Canyon, wet forest.

* Hypolepis distans v, north west and King Island, Melaleuca forest.

* Asplenium trichomanes ssp. trichomanes, v, unreserved, dry forest in State Forest in the Fingal Valley. One of the known sites is adjacent to a Pinus radiata plantation, while the other occurs near a quarry.

* Anogramma leptophylla, v, unreserved, on rock outcrop in forest at Sensation Gorge and at Chappel Street.

A statewide survey of ferns was carried out by M. Garrett for preparation of a Tasmanian Fern Atlas (Garrett, in press). Some further targeted searching on the above species is likely to be productive (M. Garrett pers. comm.).

(ii) Orchids

For details see orchid report.

Atlases have been prepared of both ferns (Garrett, in press) and orchids (Ziegeler, in prep.). None of the taxa listed above have been included in any recovery plan. Very general management guidelines have been prepared for the atlasing projects. This project will examine the distribution, habitat requirements and management requirements of two major groups of vascular plants, the conservation and reservation status of which were very poorly known prior to the atlasing projects. The effects of forest practices on these species is poorly known. Distribution information can be improved but knowledge of management requirements is poor.

6. STUDY DESIGN AND METHODS

The design of this study is the same approach detailed in Barker et al (1995), with the only variations made because of differences in the biological characteristics of the groups.

Existing and historical information will be collated and, with the expert knowledge of the project officers, will contribute to the mental predictive models which will guide further field survey.

Data on location (GPS controlled), habitat, health of stand, population size and structure, forest type, ecological notes (e.g. observations on competition, species and population vigour in relation to various environmental attributes). The type of information required for the Criteria For Listing for nationally threatened species would be collected - this relates mainly to population numbers, number of populations or metapopulations, health of stand and whether it is in decline or otherwise.

Surveys will be carried out on foot. All records made will be entered into the WILDLIFE ATLAS and will be to within 100m spatial accuracy. The data will be used in predictive modelling under another component of the CRA.

Results will be used to reassess conservation and reservation status through assessment of the Criteria for Listing information and using the RAVAS method. Observations will be compiled on field proformas and used for preparing management guidelines and recovery plans. The Criteria for Listing justifies a species listing as nationally threatened according to new IUCN criteria.

Plans will consist of a report comprising management guidelines for each species, for inclusion in the Management Manual for Threatened Forest Species and also Recovery Plans for the nationally threatened orchids and a plan for ferns. Single Species plans will be prepared only where appropriate and Group Plans will look at species x species requirements.

Tasks Duration Completed by

1. Collate published and unpublished information 1 mth July

2. Survey forests for threatened orchids and ferns 1 mth August

3. Determine Impacts 1 mth September

4. National Criteria for Listing document 1 mth October

5. Management Guidelines for the Management Manual 1 mth November

6. Recovery Plans 1 mth December

Total 6 mth

7. OUTCOMES

* Better understanding of the biology, ecology and nature of impacts on ferns and orchids including distribution maps.

* Improved conservation safeguards for ferns and orchids in Tasmania.

* Species by species treatments for the Management Manual for Threatened Forest Species.

* Recovery plans for nationally threatened species of orchids and ferns.

* Electronic and / or map products suitable for contributing to national estate thematic assessments will also be produced as negotiated with the AHC.

8. BUDGET

ANCA PWS

Fern project officer

6 months at technical officer level 4 ($35 904) 17 950 -

28% on costs 5 030 -

office accommodation, 24 wks at $120 pw 1 440 1 440

office support, 24 wks at $200 pw 2 400 2 400

computer expenses 2 570 -

supervision, 5 days at $400 per day - 2000

travel allowance, 25 days at $110 per day 2750 -

consumables 1 520 -

hire of GPS, 25 days at $25 per day - 625

rental of other equipment, 6 mths at $100 pm - 600

- -

SUB TOTAL, FERN COMPONENT $33 660 $7 065

Orchid project officer

6 months at technical officer level 4 ($35 904) 17 950 -

28% on costs 5 030 -

office accommodation, 24 wks at $120 pw 1 440 1 440

office support, 24 wks at $200 pw 2 400 2 400

computer expenses 2 570 -

supervision, 5 days at $400 per day - 2000

travel allowance, 25 days at $110 per day 2750 -

consumables 1 520 -

hire of GPS, 25 days at $25 per day - 625

rental of other equipment, 6 mths at $100 pm - 600

SUB TOTAL, ORCHID COMPONENT $33 660 $7 065

TOTAL FOR WHOLE PROJECT $67 320 $14 130

9. JUSTIFICATION OF BUDGET

The project officer salary will employ two project officers each for six months and is itemised as shown in 8.

10. OTHER FUNDS

These are itemised in 8.

REFERENCES

Barker, P. et al. (1996) ANCA Project proposal: Research and recovery requirements for the management of threatened plant species in Tasmania's commercial forests. CRA document.

Curtis, W.M.C. (1979) THE STUDENTS FLORA OF TASMANIA. Part 4a, Government Printer, Hobart.

Flora Advisory Committee (1994) Native higher plant taxa which are rare or threatened in Tasmania. Edition 1. Species at Risk, Tasmania - Flora. Parks and Wildlife Service, Tasmania.

Garrett, M. (in prep.) : An Atlas of Ferns in Tasmania, Tasmanian Forest Research Council and Forestry Tasmania.

Garrett, M. (1992) Pteridophytes of North-eastern Tasmania. Tasforests 4 : 57-68.

Garrett, M. (1995) Distribution and ecology of ferns on dry rock outcrops in Tasmania, with special reference to Fingal Tier. Tasforests 7 : 77-92.

Thackway, R. and Cresswell, I.D. (Eds) (1995) An Interim Biogeographic Regionalisation for Australia: A framework for setting priorities in the national reserves system cooperative program. Version 4.0 ANCA, Canberra.

Ziegeler, D., Jones, D., Tonelly, P., Wapstra, H., and Harris, S. (1996) : Orchid Atlas of Tasmania. Unpublished Report to Australian Heritage Commission.

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