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YELLOW THROAT The newsletter of BirdLife Tasmania: a branch of BirdLife

Australia Number 107, Spring 2019

General Meeting Thursday, 12 September, 7.30 pm

This month’s presentation is by James Pay: Investigating the conservation requirements of the

Tasmanian wedge-tailed eagle (Aquila audax fleayi).

James has focused his research towards the behavioural ecology of birds. After completing his

undergraduate degree in zoology at Aberystwyth University, he worked as a research assistant with

the Royal Society for the Protection Birds and the Centre National de la Recherche Scientifique

investigating foraging and breeding behaviour of both endangered and common bird species

throughout Europe. His work in animal behaviour has led to an interest in how ethological studies

can aid in guiding the conservation management of threatened bird populations.

Abstract: The overarching goal of James’ PhD research was to inform the conservation management

of the endangered Tasmanian Wedge-tailed Eagle (Aquila audax fleayi). Prior to this study,

conservation efforts had focussed on the threats of breeding habitat loss and disturbance to nesting

eagles, but little is known about the habitat requirements of other life stages, or the extent of other

threats that may impact survival. Using GPS tracking, James investigated the behaviour and habitat

associations of 25 juvenile Tasmanian Wedge-tailed Eagles. This data was used to develop models

that predicted where different behaviours are likely to occur in the Tasmanian landscape.

In addition… Using

data from Birdata

surveys, Warren Jones

will show the differences

in bird utilisation of the

different forest types in

the Peter Murrell

Reserves.

Meeting venue: Life

Sciences Lecture Theatre

1, Life Sciences

Building, University of

Tasmania, Sandy Bay.

Access and parking are

from College Road or

from the parking area

outside the University

Centre via the pedestrian

bridge over Churchill

Ave. Everyone is

welcome to stay for tea

and coffee afterwards.

Fan-tailed Cuckoo. Photo by Michelle Turner.

Spotted Pardalote at Peter Murrell. Photo by Sue Jones.

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Yellow Throat is now issued quarterly. Each month, BirdLife Tasmania is producing an e-

bulletin, Tasmanian Branch e-news, which goes out to members and supporters. Every third month it

is dedicated to distributing Yellow Throat electronically, while in other months it will contain events,

short articles, news, volunteer opportunities and, of course, wonderful photographs.

In this issue of Yellow Throat General Meeting Thursday, 12 September, 7.30 pm ........................................................................... 1

Black Swans – Graceful Waterfowl or Vermin? ................................................................................. 2

Revisiting the Bird and the Blade ........................................................................................................ 4

What’s happening in my patch? ........................................................................................................... 8

In the foothills of kunanyi ................................................................................................................ 8

BirdBanding NW Tasmania ................................................................................................................. 9

Pallid Cuckoos ................................................................................................................................... 10

Will this be a Shining Bronze-Cuckoo season? ................................................................................. 11

Eyes bigger than stomach? ................................................................................................................. 13

BirdLife Tasmania news and views ................................................................................................... 14

Australian Bird Environment Fund (ABEF) grant ......................................................................... 14

Draft Tasman National Park Fly Neighbourly Advice (FNA) ....................................................... 14

Listing of threatened species and communities ............................................................................. 15

Southern excursions ....................................................................................................................... 15

North-west walks and talks ............................................................................................................ 15

Twitchathon 2019 .......................................................................................................................... 15

Opportunities for involvement ....................................................................................................... 16

November BirdLife Tasmania General Meeting ........................................................................... 16

Black Swans – Graceful Waterfowl or Vermin? By Ralph Cooper

Two events promoted an investigation into the slaughter of swans on farmland bordering the Tamar

Key Biodiversity Area (KBA)/Conservation Area. One of our members was very concerned about a

fusillade of shots which seemed to come from the eastern shore on June 7. An earlier shooting episode

near the old George Town Road at Dilston had already been reported to the Wetland Centre. Duck

shooting ceased along the whole of the Tamar in 1979. The Conservation Area/KBA is managed by

Parks and Wildlife and extends from Launceston to the Batman Bridge.

Further contact with the complainants in Dilston revealed that two neighbours had

witnessed swans being shot just over the road. The details are quite graphic and were written in full

because of the proximity of the main road and they thought that the police may be involved.

Amazingly, although shooting is illegal within 250m of a property, there are no regulations regarding

shooting by a road – even though, in this case, there is a school bus stop nearby. It should be noted,

however, that the shooting was taking place parallel with the road, not towards it.

A string of letters to The Examiner regarding culling was picked up by the ABC in Hobart and

I was asked if Laura Beavis, from Launceston ABC, could contact me. A meeting with the local

residents and the farmer failed to placate several people and a further meeting was promised after

July 8. Days passed with further approaches from the ABC. No meeting seemed to be forthcoming

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so we decided to go out and do some filming. Too bad that a meeting was called for the very next

day.

The delay in holding a second meeting was in a way fortuitous because the time gap revealed

that 'clean kills' do not always take place. On June 21 one of our members took a photo of a swan

near the Wetland Centre which had the left wing missing. She took another photo of a swan on July

30 with the right wing missing. This situation was of course brought up at the second community

meeting on July 31 and the photo was tabled in Parliament by an agitated Greens member in the late

afternoon of the same day.

A Game Management representative produced a graph which purported to show a healthy

population of swans in Tasmania, but which was totally unconvincing because no reference was made

to the local breeding population, nor to local movements (in 2018 there were 90 breeding pairs on the

lagoons at Cape Portland. The Summer Count this year showed no breeding – no water – no swans).

It has been known since the late 1970s that swans can move just as ducks move in response to drought.

We can only speculate as to whether some swans in Tasmania are 'mainland swans'. No subspecies

of course, so no clues as to origin. However, we do have proxies – in the 4-year surveys for the Atlas

from 1998-2002 there are two records only of Pink-eared Duck. Last June there were 16 on the Tamar

wetlands. Freckled Duck showed zero records in the Atlas period, but in the last 2 years, over 100

have been recorded both in the Hobart and Launceston areas.

The Meeting at Dilston on July 31 aired both farm concerns as well as Birdlife issues. The

farmer was made aware of the importance of reed beds near both banks of the Tamar as habitat for

the endangered Australasian Bittern. Drone activity for moving swans could compromise breeding

activity and this was made known when the farmer thought he might try a drone to move the swans.

He had already tried crinkly silver paper, flags and gas guns to no avail. Shooting will no longer take

place on the Dilston marsh, which has been a breeding area for decades. Interference with nests and

eggs, which was suggested by a resident at the first meeting, will not be allowed under permit.

We acknowledge that there is a problem though – the presence of 500 swans on 20 ha of high-

protein grass (sown especially for breeding heifers) is entirely credible. It was established to our

Injured Black Swan, Tamar wetlands. Photo by Helen Cunningham.

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satisfaction that the severing of swans’ wings was caused by panic collision with fence lines and not

by shots.

A joint investigation by Birdlife and the ABC established that there are two licences, each with

a permit to take 100 birds per year, on both sides of the river. Both licencees could shoot at the same

time. So far this year, in addition to the two Tamar culling permits, there are 33 current permits in

undisclosed parts of Tasmania. The question of whether permits are/have been issued for more than

100 birds has not been answered. The total swan kill for the two farms bordering the KBA is 460

for the two years to the end of May this year. Permits may be issued at any time of the calendar year.

The kills for the last four years in Tasmania are:

2015 2016 2017 2018

2172 1677 2451 1748

At least we have opened things up for further discussion – Game Management seem adept at avoiding

disclosure of statistics unless really pressed.

In conclusion, it should be mentioned that discussion between the farmer and Birdlife was

entirely respectful on both sides. An account of the meeting which was submitted to Birdlife Tas

Committee was forwarded to the farmer in advance, and no significant changes were suggested.

Revisiting the Bird and the Blade By Nick Mooney

BirdLife Australia Raptor Group

The recent plethora of windfarm activity, including the controversial proposal for a 140km

transmission line eastward from the proposed Robbins Island/Jims Plains windfarms and media

inquiries around the recent release of the proposed St Patricks Plains windfarm’s eagle nest survey,

leads me to revisit the issue.

For years I have been assured by officialdom including the Tasmanian regulator (the

Environmental Protection Agency) and different government ministers that both ‘…a robust

procedure is in place…’ and ‘…the assessment process and offset program are under review…’. But

it seems that nothing substantial has changed since the mid-2000’s beginnings and we are still stuck

with oddly clunky assessments, lack of progress in the face of continued eagle strikes, many more

windfarm proposals (to date for more than 500 turbines). I think industry can and should do much

better and not just limit itself to simply what is required by the regulator.

Prevention of Collisions

Prevention obviously should be the priority but we fail immediately through a lack of strategic

planning. Some countries such as South Africa and Spain are ‘risk mapping’ their land to look for the

places with the best combination of wind suitability and low impacts on the environment. Here in

Tasmania we appear to just sit back and wait for someone to find enough money to build wherever

they can, essentially without environmental guidance. It’s simply pot luck whether a proposal is in a

high density of eagles and other values or not. Widespread point surveys of the Where? Where?

Wedgie type would be very useful in strategic planning for potential windfarm sites.

This complete lack of strategic planning stems from a lack of focus and will – the last Recovery Plan

for Tasmania’s threatened eagles (Threatened Species Section 2006) is now painfully out of date.

Much faith seems to be invested in a collision-reduction package being installed at the Cattle

Hill windfarm using camera recognition of flying eagles that slows/feathers nearby turbines to try

and reduce collisions risk. Well, the recognition part seems to work okay overseas but translating that

into actually reducing collisions has not been demonstrated anywhere. I hope it works.

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Assessment of Risks to Eagles of Particular Windfarms

Looking from the outside, the Eagle Utilisation Surveys used in assessment are not very useful. They

essentially consist of observers looking for eagles around the site and writing down where they think

the eagles they see are and how high they think they are flying. There are many sources of error,

beyond misidentification at a distance. The numbers of birds being seen (in a period) is not known

since there is no means of identifying individuals. Some eagles are curious and will rotate around

observers checking them out and eagles often shadow people to see what prey they might flush. So,

there can be substantial observer influence and double (and more) counting. Importantly, there has

been no calibration of judgments even though there are GPS-tagged eagles elsewhere in Tasmania

that could be used. Such direct observation to guesstimate factors that would greatly benefit from

precise measurement seems rather Dickensian in 2019 when GPS tagging is commonly used now for

such things. It seems almost perverse that the GPS-tagging eagle study in Tasmania that is producing

amazing data on things other than windfarms is partly supported by the windfarm industry yet the

tool is not used in their back yards (except for one tagged eagle in the northeast).

Eagle Utilisation Surveys are used to help locate turbines but windfarm industry publications

themselves claim that eagles modify their flight behaviours once turbines are constructed (eg Hull

and Muir 2013), somewhat making nonsense of the whole exercise. The enormous expense involved

in the current observational assessment might well be better directed at GPS tracking. Advocates

claim Eagle Utilisation Surveys lead to some nests being found but with the thorough searching for

nests that is undertaken I can’t see they are needed for that.

The location of nests already known or through a new Eagle Nest Survey leads to a buffer

distance of 1km to turbines nominated by the regulator (a distance the regulator has seen fit at the

Point Latta windfarm to reduce, under industry pressure). Unfortunately, the 1km is completely

arbitrary in terms of protecting eagles from physical danger and looks increasingly bizarre in the face

of ever-taller turbines

which almost loom over

some nests. And even if

the turbine base is 1km

away the huge blade

tips can be much closer.

The 1km is in fact ‘cut

and pasted’ from

guidelines I came up

with 30 years ago to

protect active nests

from the disturbance of

forestry operations.

One would think that in

2019 when spending

billions we might have

data-driven protocols

not just convenience.

Other countries are

using data from GPS-

tracked nesting eagles

to set the buffer

distance (usually more

than 4km). Flight

intensity usually

suddenly dilutes at a

certain distance from

Wedge-tailed Eagle, Tasmanian sub-species. Photo by Alan Fletcher.

Wedge-tailed Eagle, Tasmanian sub-species. Photo by Alan Fletcher.

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nests – that’s how buffers for physical safety are decided, not borrowing from a completely different

issue. The regulator mirrors the usual industry claim of ‘...no impact on nesting eagles…’ but quoted

publications also claim eagles change behaviours in response to turbines (isn’t that an impact?) and

the study on eagles breeding close to turbines (Hull et al. 2015) gives a clear warning about the study’s

lack of robustness.

Without marked birds and/or very sophisticated DNA study at windfarms and control sites

study it’s also impossible to know the turnover of eagles at windfarms and compare it to other areas.

They well might be population sinks and we wouldn’t even know with the current paucity of data.

Assessment of Population Impacts

Having enough GPS-equipped eagles of various age groups would allow the accurate estimate of

local survivability and population densities, essentials for a proper Population Viability Analysis,

without which any calculation of sustained yield and accumulated impact is unreliable. The Cattle

Hill windfarm proposal, for instance, came up with a statewide sustainable yield of 29 per year from

anthropogenic causes. Well, we know that many are killed on power distribution infrastructure alone

(forget accidental poisoning, persecution, collisions with turbines, vehicles and fences), highlighting

the estimate’s fragility.

My questions to the EPA on how it accounts for accumulated mortality in its assessments

simply go unanswered because with current poor data they can’t do the necessary sums. Now that in

2019 we have the means, the regulator should insist on high-quality data so meaningful assessments

can be made.

The regulator’s claim that windfarms cause no significant impacts on populations of Tasmanian

eagles is a familiar twist on the fact that there is no data to show they do – a very different thing. The

(scary) fact is, there is no data.

Assessing Mortalities

The miniscule areas searched under some turbines for dead or catastrophically injured birds (such

that fall almost straight down) is, at best, an uncalibrated index. Originally, larger areas were searched

but never with dogs, a method proven to increase detectability, especially of fragments of birds.

Therefore, the industry mantra and regulator mantra that what’s found represents what is hit seems to

me a somewhat Machiavellian feedback loop. Having enough GPS-tagged birds would give us very

exact measures of risk to eagles in and around windfarms.

Such assessment should, of course, start well before commissioning and it’s very disappointing

to see windfarm after windfarm avoid such direct study instead favouring sloppy methods that give

more 'wriggle room’. GPS study of enough eagles would allow calibration of the index the above

partial searches present and might even allow back-calculation of past mortality. But I am even

dubious about the value of the searches as an index in that the methods keep changing, especially in

regard to means of transport during searches (foot, quads, 4WDs etc) likely being a key factor

affecting detectability of dead and injured birds and bats.

Offsetting Impacts

Offsets in Tasmania have been varied, as allowed under the Commonwealth policy.

Importantly, the effectiveness of offsets in offsetting deaths and breeding disruption has not been

measured – their application so far seems more an act of faith than anything. Covenanting or

otherwise protecting private land around viable nests under threat from things other than windfarms

has the potential to offset nests compromised by windfarms but its effectiveness in terms of

productivity clearly should be routinely measured as part of the offset but isn’t. Extending

covenanting nest sites into compensation for eagle deaths is far more problematic in that productivity

would have to be elevated to compensate for the ages of different eagles killed (eg a dead juvenile

might be represented by 1 more fledgling whereas a dead adult might need 15 more fledglings).

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Offsetting mortalities per se however, has much more direct alternatives. Todd Katzner, a

leading American researcher in the field who also knows Tasmania advocated to me an obvious

offset often applied in the USA:

1. Measuring mortality/incapacitation estimates each year at the windfarm(s) (eg 5 deaths/year)

2. Measuring deaths/incapacitations from power-distribution infrastructure (eg 1 eagle/yr /200km)

3. Making (and keeping) the equivalent distance of line (eg 2 X 200 = 400km) bird-safe (this may

involve prioritising sections).

The alternative (1.) he describes is estimating deaths/incapacitations at windfarm(s) over the

proposed life span of the windfarm(s), proactively translating that into ‘bird safe-ing’ (eg 2

deaths/year over 30 years = 60 deaths which translates to 12,000km of distribution infrastructure,

which can have sections prioritised of course). This has the obvious advantage of accelerating the

solving of eagle deaths on power distribution infrastructure, a strategic approach that has much to

recommend it. The whole idea is to make sure the new industry (windfarms) leads to no net increase

in mortality and yes, it can be done.

As things are going, I fear all the windfarms will be approved before there is a useful

improvement, but it doesn’t have to be so. I say we use proper study to test the windfarm industry’s

and the regulator’s confidence that impacts of Tasmanian windfarms on eagles are insignificant at

population levels. I hope they are right.

References and additional reading:

Elliott, D (2019) Wind turbine impacts deplored. Physicsworld. 29 August 2019,

https://physicsworld.com/a/wind-turbine-impacts-deplored

Hull, CL and Muir, SC (2013). Behaviour and turbine avoidance rates of eagles at two wind farms in

Tasmania, Australia. Wildlife Society Bulletin, 37(1), pp.49-58.

Hull CL, Sims C, Stark E and Muir S (2015). Results and analysis of eagle studies from the Bluff

Point and Studland Bay Wind Farms 2002-2012. Pp. 95-111 in Hull, CL, Bennett, E, Stark, E,

Smales, I, Lau, J and Venosta, M (2015). Wind and Wildlife. Proceedings from the Conference

on Wind Energy and Wildlife Impacts, October 2012, Melbourne, Australia. Springer.

Dordrecht, Heidelberg.

White-bellied Sea Eagle (young adult). Photo by Helen Cunningham.

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Threatened Species Section (2006). Threatened Tasmanian Eagles Recovery Plan 2006-2010.

Department of Primary Industries and Water, Hobart.

Watson, R, Kolar, P, Ferrer, M, Nygard T and Johnston, N (2018). Raptor Interactions with Wind

Energy: Case Studies from Around the World. Journal of raptor Research 52(1) pp1-18.

What’s happening in my patch?

This is the first in a series of reports from different contributors about their ‘patch’: an area that they

have been monitoring for some time. We are also publishing ‘patch notes’ in the e-bulletin. The patch

reports are longer and more detailed than the patch notes; they describe and analyse observations

recorded during regular surveys. Patch notes can be about more informal observations. If you would

like to contribute to either series, please contact me. ― Ed.

In the foothills of kunanyi By Mona Loofs-Samorzewski

I live on the side of kunanyi/Mt Wellington in Hobart, in a little community of 13 houses with a range

of gardens in one half and bush in the other half – tall white gum trees, bracken and shrubs in the

understory and a moist rainforesty creek at the bottom. I’ve been keeping track of the birds there ever

since I moved in nearly 20 years ago, and it’s been interesting to watch the birds change and to see

how I have changed in the way I interact with the birds over that time.

In the first few years I just noted down all the different species I saw, to build up a list of what

was there, only adding a species when it was something new and not really noticing when or where I

saw the bird. After a while, adding a new bird happened more rarely, and I began to wonder about

the birds I saw regularly.

I decided to make a list of the birds I

saw each month, and this was a revelation! It

was over several years that I learned about

the comings and goings of the species in my

patch. I noticed that Fan-tailed Cuckoos,

Pallid Cuckoos and another curious

sounding bird which I heard for ages before

finally finding and identifying as a Shining

Bronze-cuckoo, all appeared and called in

the spring months, becoming less obvious

over summer and disappearing completely in

autumn and winter. Before my monthly lists

I vaguely noticed that I heard some birds at

some times and not others, but now I could

identify specific species and particular times,

which lead to reading up about cuckoos and

learning about their life cycles.

Many other birds followed this pattern: Black-faced Cuckoo-shrikes, Brush and Common

Bronzewings, Striated Pardalotes and Welcome Swallows. There were exceptions sometimes: a

surprise encounter with a Bronzewing in winter (aha, they just go quiet in winter but they are still

around!) and one year when the Striated Pardalotes decided to stay. But there were other patterns

also: Yellow-throated Honeyeaters appeared in summer and autumn, and were virtually absent in

spring. Golden Whistlers, Crescent Honeyeaters and Scarlet Robins did something similar but a little

later, turning up later in autumn and winter and continuing on into spring but gone by summer. I read

up in field guides and bird books about migration and was amazed to find out how many species leave

Tasmania over winter and how far they go. I also learned about altitudinal migrants, that come down

from the mountain in the winter months to take advantage of our gardens.

Black-faced Cuckoo-shrike. Photo by Michelle

Turner.

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I got to know the big obvious regulars: Masked Lapwing, Sulphur-crested Cockatoo, Green

Rosella, Grey Currawong, Black Currawong, Laughing Kookaburra, Grey Butcherbird, Yellow

Wattlebird, Common Blackbird and Forest Raven (it’s not a list if it doesn’t have a Raven on it!).

And the smaller, more unobtrusive regulars: Superb Fairy-wren, Eastern Spinebill, Black-headed

Honeyeater, Brown Thornbill, Grey Fantail and Silvereye. I discovered Tasmanian Scrubwren in the

creek, identified my very first Tasmanian Thornbill and watched Kelp Gull regularly fly overhead.

After a while these monthly presence/absence lists were not quite detailed enough, and I made a

commitment to do weekly lists including species counts and any breeding activity that I noticed. I did

this for all of 2016 and then again (although less consistently) in 2018. I tried going out at night and

met my first (and only) Masked Owl, realised that Tasmanian Boobook (called Morepork in some

taxonomies) also disappeared over winter, had a few lovely encounters with Tawny Frogmouths and

even heard an Owlet-nightjar! I’ve witnessed Australian Wood Ducks prospecting for nest sites (our

trees weren’t good enough apparently), Grey Currawongs raising chicks in messy stick nests, Superb

Fairy-wrens enjoying tangled blackberry shrubs to raise their families and heard the really weird

sounds that baby Yellow Wattlebirds make.

I’ve also noticed changes over time, such as the way all the European Sparrows suddenly

disappeared in June 2009 and it wasn’t until September 2013 that they recovered. A few birds I saw

early on (European Greenfinch and one Satin Flycatcher sighting) I’ve never seen again, and a few

new birds have arrived since I’ve lived here. The most notable arrival was the Tasmanian Native-hen

– I always wondered why we didn’t have

them, there was plenty of grass and water

nearby – suddenly in 2008 they turned up

and it’s never been the same since!

It’s great fun watching them

interact, they have raised many families

over many years and have split into the

Western Gang and the Eastern Gang with

predictable arguments when they meet.

Little Wattlebirds started appearing

around 2010 in autumn, they tend to hang

around for a month or two feeding on

Banksia cones, then they disappear until

next year. One newcomer I am not

particularly happy about is the Spotted

Dove, I first heard one in 2010 and since

the end of 2018 they have become more

regular, strutting around on the paved

surfaces like they’ve always been here.

Altogether I have counted 70 different

species, have been delighted by surprise

visitors (Swift Parrot and White-throated

Needletail to name a couple), enjoyed

getting to know my locals and learned a

lot about birds in the process.

BirdBanding NW Tasmania By Geoff Shannon Documenting population change in bird numbers is important, but what is the next step? It was with

this in mind that I started this project in early 2016 in an attempt to develop a figure for adult

survival year to year and some idea of immatures produced per year and their survival over the first

winter.

Tawny Frogmouth with chick. Photo by Helen

Cunningham.

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Eight sites in woodland were selected for this project and over the first 39 months more than

300 hours in the field have resulted in just over 1000 birds caught and more than 100 retrap events.

Twenty-nine species have been banded.

The top five species were Brown Thornbill (192), Superb Fairy-wren (158), Silvereye (111),

New Holland Honeyeater (94), Tasmanian Scrub-wren (92) and Yellow-throated Honeyeater (73).

Of interest was the variation in percentage of immatures from year to year: Tasmanian Scrub-wren

30-45%, Superb Fairy-wren 29 to 52% and Brown Thornbill 18 to 67%. This needs to be followed

for a few more years to see if there is a trend.

Retrap rates for Tasmanian Scrub-wren immatures were 27% and 25%, Superb Fairy-wren

12.8% and adult 13.6%, Brown Thornbill immature 15% and adult 25%.

This is a summary of Geoff’s fascinating talk at the July General Meeting of BirdLife Tas.

Mike Newman

At the last BirdLife Tasmania General Meeting, Mike described how he used Birdata to compare

the status of Pallid Cuckoos in Tasmania with the Hunter region of NSW where he used to live.

Pallid Cuckoos are summer breeding visitors to south-east Australia. In Tasmania 95% of the records

are between September and January, when the birds are highly vocal. In autumn they depart with

most spending the winter in north-western Australia.

In the Hunter region Pallid Cuckoos have become increasingly scarce over the last 20 years. In

contrast, Tasmania appears to be a stronghold of the species in the breeding season. Indeed, Birdata

surveys suggest that Pallid Cuckoos have increased in the last 20 years. However, that increase may

be an illusion because it is not supported by the trends at several locations where there are extremely

reliable data sets. At these locations the species has either remained stable or decreased, although

remaining plentiful in suitable habitat. Pallid Cuckoos favour dry woodlands with limited

understorey, ideally in a fragmented landscape which retains a high level of tree cover.

Understanding Birdata trends requires a knowledge of the lifestyle of the target species (e.g. its

habitat preferences). In the case of the Pallid Cuckoo it is also important to understand the

requirements of the brood host which raises the Pallid Cuckoo’s young. The literature lists 80

Female Superb Fairy-wren. Photo by Michelle Turner

Pallid Cuckoos

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different hosts, but individual cuckoos only parasitise one type of host species, Black-headed

Honeyeaters being a preferred host in south-east Tasmania.

Relatively little is known of the breeding behaviour of Pallid Cuckoos, but a related species,

the Common Cuckoo of the northern hemisphere, is exceptionally well studied. Female Common

Cuckoos typically find 20 to 25 brood nests, in which eggs are laid at 48-hour intervals. During that

period the female Cuckoo is extremely secretive as it watches its hosts and surreptitiously replaces

one of their eggs with one of its own. Males, on the other hand, roam widely, advertising their

presence to keep in contact and mate with the females. However, the male is also secretive and more

often heard than seen. It is probable that Pallid Cuckoos’ home ranges greatly exceed the size of

survey sites, as cuckoos roam in both their preferred habitat for food and that of the host, which may

have different habitat preferences. Collectively, these issues result in superficially anomalous survey

results, with the Reporting Rates of Pallid Cuckoos in the dry woodland of eastern Tasmania

exceeding that of its host the Black-headed Honeyeater by two or more times. However, Black-

headed Honeyeaters are clearly more numerous. The explanation lies in the loud, frequently uttered

calls of adult cuckoos in the breeding season, which increase their detectability.

There is evidence that adult Pallid Cuckoos may intervene in the care and ‘education’ of

fledged young. For instance, the food fed by host species may be very different from the hairy

caterpillars, grasshoppers and similar insects which are the staple diet of adult Pallid Cuckoos.

Mike’s article comparing Pallid Cuckoos in the Hunter and Tasmania will be published

on-line in Whistler, the journal of the Hunter Bird Observing Club, in the near future. – Ed.

Will this be a Shining Bronze-Cuckoo season? By Mike Newman

Spring approaches and the cuckoos return to torment their Tasmanian hosts. While there has been

recent focus on fluctuations in the abundance of Horsfield’s Bronze-Cuckoo the status of the more

common relative the Shining Bronze-Cuckoo receives little attention. Well that is until you are trying

to recapture ones carrying geolocators as described by Cat Young at our July General Meeting during

which she suggested that they were less numerous than usual last year in the Waterworks reserve

area.

Pallid Cuckoo, South Arm. Photo by Alan Fletcher.

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I decided to test the generality of this observation starting with my Meehan Range data where

I carry out monthly surveys at 6 2ha survey sites. The results shown below confirmed Cat’s

impression with no records in the 2018/19 breeding season and evidence of a five-year decline. In

contrast although the Fan-tailed Cuckoo has also decreased over the same period its numbers

remained relatively stable.

Figure 1. Reporting Rate trends of Shining Bronze-and Fan-tailed Cuckoos for breeding season surveys (Sep.

– Dec.) in the Stringybark Gully section of the Meehan Range.

To test the extent which these experiences were Hobart-centric I examined the whole-of-Tasmania

Birdata and found only limited support for the conclusion that there had been a serious crash in the

Shining Bronze-Cuckoo. The breeding season reporting rates of the more reliable 2ha 20- minute

Figure 2. Breeding season reporting rates of Shining Bronze-Cuckoos at Lake Llewellyn (5 km surveys) and

Woodsong (500 m surveys).

0

2

4

6

8

10

12

14

16

18

2014/15 2015/16 2016/17 2017/18 2018/19

Rep

ort

ing

Rat

e (%

)

Shining Bronze-Cuckoo Fan-tailed Cuckoo

Linear (Shining Bronze-Cuckoo) Linear (Fan-tailed Cuckoo)

0

10

20

30

40

50

60

70

2010/20112011/2012 2012/20132013/2014 2014/20152015/20162016/2017 2017/20182018/2019

Rep

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)

Lake Llewellyn) Woodsong Linear (Lake Llewellyn)) Linear (Woodsong)

13

and 500m survey sets were 4 and 19% lower respectively than in the previous year (2017/18). There

was a larger decrease of 33% in the 5 km surveys which are strongly influenced by Richard Ashby’s

surveys at Lake Llewellyn in north-west Tasmania, which are shown in Figure 2.

Wondering what had happened in north-east Tasmania, I compared the trend at Woodsong

using Albert Nichols’ surveys and again found that Shining Bronze-Cuckoos were at a near decade-

long minimum in 2018/19.

There is an interesting similarity in the trends at Lake Llewellyn and Woodsong with both

indicating a long-term decrease in separate regions of the state. Both also show periodic fluctuations,

which may be a consequence of the Cuckoos shifting to another area to prevent their host becoming

habituated to their presence.

Richard, Albert and I will return to our patches this spring hoping our Cuckoos come back and

we all wish Cat success in recovering her geolocators so that she is able to tell us where they went.

Eyes bigger than stomach? By Sue and Warren Jones

Each year over winter we get occasional visits from a Grey (=white) Goshawk in the garden of our

house in Kingston. Our neighbour has an aviary, and the goshawk has been known to perch nearby

eyeing off the lovebirds.

We are sometimes alerted to the goshawk’s presence by ‘angry raven’ calls when our resident

pair of Forest Ravens spot and then see off the interloper. Usually this has seemed a very one-sided

affair as both ravens, occasionally aided by the local Grey Butcherbird, continually harass the

goshawk until it leaves the area. However, this year on two occasions the goshawk has flown directly

at one of the ravens which was perched in a tree. On the first occasion we thought it may have been

just trying to chase the raven off, but on the second occasion it looked a little more serious and we

wondered if the goshawk saw the raven as a potential meal, notwithstanding that the goshawk looked

no bigger than the raven.

A little research suggests that this is possible. A chart in Olsen’s Australian Birds of Prey

shows that a male Grey Goshawk may take prey of up to 800g, while a female may go as high as

The visiting Grey Goshawk. Photo by Sue Jones.

14

1300g. They can, and do, take prey bigger than themselves. Menkhorst et al. (2017) record the

weight of Forest Ravens as 500–770g. More detailed information on the diet of the Grey Goshawk

in Tasmania has been collected by Nick Mooney and reported in Olsen et al. (1990). Looking at the

diet in both the breeding and non-breeding seasons, this paper records 30 species of birds (62

individuals) as prey items in Tasmania. Mammals and reptiles also form a portion of the goshawk’s

diet. The smallest birds recorded as prey are fairy wrens and thornbills (a light snack?) ranging up to

the heaviest bird being a single Forest Raven taken by a female Grey Goshawk. Other large birds

recorded as prey include a white-faced heron, cattle egrets, a kookaburra and currawongs.

So, it seems that our ravens are right to be wary of Grey Goshawks and to drive any that appear out

of their territory as quickly as possible. Juvenile ravens or sick or injured adults would be at most risk

and healthy adults may be vulnerable only to the larger female goshawk. For now, and especially

when working together, our pair seem to have the upper hand.

References:

Menkhorst, P, Rogers, D, Clarke, R, Davies, J, Marsack, P and Franklin, K (2017). The Australian

Bird Guide. CSIRO Publishing.

Olsen, P (1995) Australian Birds of Prey. UNSW Press.

Olsen, PD, Debus, SJS, Czechura, GV and Mooney, NJ (1990). Comparative Feeding Ecology of the

Grey Goshawk Accipiter novaehollandiae and Brown Goshawk Accipiter fasciatus. Australian

Birdwatcher 13, 78 – 192.

BirdLife Tasmania news and views

Australian Bird Environment Fund (ABEF) grant Congratulations to Mike Newman – due to his hard work, BTas was recently awarded ABEF funding

of $9000 for a project aimed at sustaining and enhancing recent gains in Birdata participation and

data evaluation. It will be a joint project with the BirdLife research team. The project has four

components:

• Production and publication of the State of Tasmania’s Birds 3 for Tasmanian Bird Report No.

40.

• Conducting workshops which explain Birdata to Tasmanian members and the broader

community. The purpose of these workshops will be to encourage increased monitoring of

bird populations in a meaningful manner and to facilitate the increased of application of

Birdata to environmental management.

• To identify gaps in the Tasmanian Birdata set that limit its use in determining the status of

bird populations and to develop strategies for addressing these deficiencies thus increasing

the effectiveness of our volunteers.

• To develop and trial approaches to assessing the health of bird populations in Key Biodiversity

Areas which are seldom visited.

This program will be carried out over the next 18 months.

Draft Tasman National Park Fly Neighbourly Advice (FNA) The Parks and Wildlife Service (PWS) advises that it has prepared a draft Tasman National Park

FNA. The draft FNA was made available for public comment on 24 August 2019 for a four-week

period until 21 September 2019.

The draft FNA has been prepared by the PWS in response to increasing air traffic over the

southern section of the Tasman National Park and adjoining areas. Whilst the PWS does not have

management authority over the airspace above the Tasman National Park, the PWS is facilitating

the FNA process - for the benefit of park visitors, values management, and local residents.

15

The draft FNA is available on the PWS website at www.parks.tas.gov.au/publications (under

‘Other Publications’).

Following public consultation, the PWS will provide the draft FNA to the Regional Airspace

and Procedures Advisory Committee for consideration. If endorsed, the FNA will be published in

aeronautical charts as a resource for pilots.

Listing of threatened species and communities In late June, the new Federal Environment Minister added a number of species and communities to

the threatened species listed under the Environment Protection (Biodiversity Conservation) Act 1998.

See:

http://www.environment.gov.au/news/2019/06/28/amendments-epbc-act-list-threatened-species-

and-ecological-communities

White-throated Needletails are now listed as Vulnerable and the Ecological Community:

‘Tasmanian Forests and Woodlands Dominated by Black Gum or Brookers Gum (Eucalyptus

ovata/E. brookeriana)’ is listed as Critically Endangered (as was recommended by the independent

Threatened Species Committee several years ago, and was stalled following the intervention of the

Tasmanian Government).

Southern excursions

North-west walks and talks The September 17th bird walk will be at the Devonport

Arboretum (Eugenana) starting 9 am. Meet 8.30 am at the

information bay Alexander Street, Shearwater.

I have also been able to organise a viewing of the raptor

photo exhibition at the education centre. (Five-dollar entry fee

to the Arboretum if not a member).

Please contact BirdLife Tasmnia if you would like to go

on the email list to find out about future walks: tasmania@birdlife.org.au

Twitchathon 2019 The Birdlife Australia National Twitchathon is a fun event

where teams of birders attempt to see as many species as

possible in a given time period, while raising funds for conservation. This year, the Tasmanian

component of the Twitchathon will be on the 26th and 27th of October, and raising money for King

Island Scrubtit and King Island Brown Thornbill habitat restoration through Birdlife Australia's

Preventing Extinctions program. Anyone can sign up for the 3-hour Birdathon, the 12-hour Big Day,

or the 30-hour Big Weekend anywhere in Tasmania, and get out and about for some birdwatching

fun with a twitching twist!

Sun 22nd

September

2019

8:30am

Ridgeway

Reservoir

One of the current Tasmania Fire

Service survey sites, part of the study

examining differences in utilisation

between original and recently burned

sites, using 20 min, 2 ha surveys and

the Birdata database

Contact BirdLife

Tasmania for more

information.

tasmania@birdlife.org.au

Sun 20th

October 2019

8:30am

Waverley Flora

Park

Enjoy a spring trip to the wonderful

Flora Park on the Eastern Shore.

Contact BirdLife

Tasmania for more

information.

tasmania@birdlife.org.au

The Tasmanian Arboretum

Presents

A Photographic Exhibition

The Raptors of Tasmania

Showcasing the images of local

photographers:

* Bert Quandt * Jill Colgrove

* Peter Tonelli * Greg Close

* Mehrdad Abbasian * Philip Milner

September 14th & 15th and 21st & 22nd

10 am to 4 pm each day in the

Arboretum Education Centre.

46 Old Tramway Road Eugenana

Admission: $5.00 for non-members

16

For more information, contact the Tasmanian coordinator by email at twitchathon.tas@gmail.com,

or visit the Tasmania Twitchathon page at https://www.facebook.com/TasTwitchathon/

Opportunities for involvement Please contact us if you would like to find out any more about the various opportunities and tasks

below. Email tasmania@birdlife.org.au and your email will be forwarded to the appropriate person

for response.

Layout person/graphic designer needed for Yellow Throat Yellow Throat is in need of a facelift. Improving the layout is beyond the capabilities of the current

editor, so if you have layout/graphic design skills and would like to contribute to BirdLife in a

rewarding and interesting way, this is a great opportunity to be involved. The commitment involved

would be 4-5 hours once every three months, starting in late November 2019.

Tasmanian wildlife fair – Koonya

We will have a stall at the Tasmanian wildlife fair again this year, on October 5, and need a couple of

volunteers to help ‘person’ the stall. This is a colourful, fun and very valuable event.

Assistance with Yellow Throat production

We would like to have a team of people to call upon for assistance with printing and posting the paper

version of Yellow Throat. The commitment involved is only 1-2 hours every three months, starting

early December 2019.

Engagement sub-committee

The Engagement sub-committee of BirdLife Tasmania meets irregularly in Hobart to discuss how we

can improve communication with and involvement of members and supporters, and we also then

work on the solutions! We are a lively, committed group of people with a range of skills and interests.

November BirdLife Tasmania General Meeting November’s general meeting will be held on Thursday 14 November. Todd Dudley, President of the

East Coast Bioregional Network, will give a presentation on the East Coast Conservation Corridor.

The venue, as usual, will be Life Sciences Lecture Theatre 1, Life Sciences Building, University of

Tasmania, Sandy Bay. All welcome.

Scarlet Robin. Photo by Michelle Turner.

17

BirdLife Tasmania 2019

GPO Box 68, Hobart 7001

tasmania@birdlife.org.au

www.birdlife.org.au/tasmania

Unfortunately, due to recent issues involving scamming emails, we cannot include

individual contact details. Please address all correspondence to BirdLife Tasmania via

tasmania@birdlife.org.au and your email will be forwarded to the appropriate person.

BirdLife Tasmania | Facebook

BirdLife Tasmania (@BirdLifeTas) | Twitter

Yellow Throat is produced every quarter beginning in March. Contributions, including

articles, sightings, birdwatching sites, photographs, letters and news, are welcome,

and will be published subject to space and interest or relevance to BirdLife Tasmania

members, at the Editor’s discretion. Views expressed in Yellow Throat are not

necessarily those of BirdLife Tasmania, or of the Editor, unless explicitly stated. The

deadline for the next issue is 20 November 2019.

All photographs remain © the photographers. We are very grateful to them for

the use of their magnificent images.

All maps drawn from the BirdLife Tasmania database remain © BirdLife

Tasmania.

Please make use of our material, but we ask that you acknowledge BirdLife

Tasmania as the source.

Shining Bronze-cuckoo. Photo by Alan Fletcher

18

We thank the office of Mr Andrew Wilkie, MHR, for assisting in the production of Yellow

Throat 107.

BirdLife Tasmania is a regional branch of BirdLife Australia