Biodiversity and Conservation 12: 555–566, 2003. 2003 Kluwer Academic Publishers. Printed in the Netherlands.

The impacts of vascular wilt disease of the takamakatree Calophyllum inophyllum on conservation value ofislands in the granite Seychelles

*MIKE HILL , DAVE CURRIE and NIRMAL JIVAN SHAH*´Nature Seychelles, P.O. Box 1310, Victoria, Mahe, Seychelles; Author for correspondence (e-mail:

nature@seychelles.net; fax: 1248-225121)

Received 10 July 2001; accepted in revised form 8 March 2002

Key words: Calophyllum, Conservation, Leptographium, Plant disease, Seychelles, Vascular wilt

Abstract. The takamaka tree Calophyllum inophyllum is an important component of indigenous coastalforests in the granitic Seychelles, found on most islands of the archipelago. In 1994, a fungal pathogenpreviously unrecorded in the Seychelles (Leptographium calophylli) was detected on takamaka. Since thefirst cases of the disease were observed, spread of the disease has been rapid, both within and betweenislands. Attempts to control the disease, involving both legislation and forest management, appear to havehad little impact in controlling the spread. In the six years since the disease was first recorded in theSeychelles, it has reached 10 islands, including most of the large islands of the archipelago. Mortalityrates and rates of spread between trees appear to vary in different islands and situations, but in some casesboth appear to be high. This paper describes the distribution of the disease in the granitic Seychelles sixyears after it was first recorded, reviews the potential impact of the disease on conservation value anddiscusses management strategies to minimise the impact of the disease on endemic vertebrates.

Introduction

The granitic Seychelles (48109–48509 S, 558109–568009 E) is an archipelago of some40 granite islands situated over 900 km from Madagascar, 1600 km from EastAfrica and 2700 km from India (Stoddart 1984). Discovered in 1609, permanenthuman settlement of the islands did not occur until 1770. Early records of theislands’ biota are poor, and the period following human settlement was one of rapidenvironmental change through deforestation, introduction of invasive alien species(both plant and animal), and plantation agriculture. In the last quarter of the 20thcentury, the potential for conservation of terrestrial ecosystems has significantlyincreased with a shift in the nation’s economy away from plantation agriculture totourism and exploitation of marine resources. However, invasive species continue tothreaten native species and semi-natural ecosystems on the islands (Shah 1995a). Arange of alien species has conservation impact, including vertebrates (Racey andNicoll 1984; M.J. Hill, in press), invertebrates (M.J. Hill, in preparation), plants

¨(Carlstrom 1996; Fleischmann 1997), and pathogens, the impact of which hasprobably been underestimated.

This paper discusses the spread, current distribution and potential impact of oneplant pathogen, takamaka wilt disease, on ecosystems of the granitic Seychelles

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using several novel case studies from the archipelago. The likely effect of thedisease upon conservation value of islands and management strategies to minimisethe impact of the disease on native habitats and endemic species are discussed.

Takamaka

Takamaka Calophyllum inophyllum [family Guttiferae] is a widespread tree speciesof the Indo-Pacific region, occurring from East Africa and Madagascar to islands ofthe western Pacific. In the Seychelles, it occurs on most large islands in a variety ofsituations from beach-crest, littoral lowland (‘plateau’) and low hill woodland(Vesey-Fitzgerald 1940) to hill woodland at elevations of up to 300 m above sealevel (a.s.l.) (FAO 1997) and occasionally more. Old, large trees can exceed 20 m inheight with stems over 1.6 m in diameter, and the timber was formerly valued forboat building (Friedmann 1994).

Biology and spread of takamaka wilt disease

Takamaka wilt disease is caused by the fungus Leptographium calophylli, previous-ly designated as Verticillium and Haplographium (Webber et al. 1999). The funguscauses extensive wilting and dieback of takamaka trees, and can lead to completedefoliation and death of trees within months (Ivory et al. 1996). There is someinconclusive evidence for regrowth from the main stems of some defoliated trees(FAO 1997), but this may not represent significant recovery of trees. Spores of thepathogen appear to be distributed by the bark beetle Cryphalus trypanus [familyScolytidae] (Wainhouse et al. 1998), a species endemic to the Seychelles andpreviously only recorded on the endemic tree Northea hornei [family Sapotaceae] at650–700 m a.s.l. (Beaver 1987).

The origin of the disease in the Seychelles is unknown: since the disease was notrecorded in the Seychelles prior to 1994 (Ivory and Andre 1994), it seems likely tobe caused by an exotic species, or an exotic virulent strain of a native species.Takamaka wilt disease was first noted in Mauritius in the 1930s (Wiehe 1949), andsimilar (or identical) diseases have been recorded on Calophyllum species in ElSalvador, India and Indonesia (Ivory et al. 1996). However, because data on plantdiseases in the Seychelles are scarce, we cannot exclude the possibility that thedisease is an outbreak of a fungal species normally found in the trees, but releasedby environmental change or plant stress (FAO 1997). Currently, there are no data onrates of mortality.

´By 1995, over 300 trees on Mahe showed symptoms of the disease, all in thenorth of the island, and the disease spread to neighbouring islands in the granitic

´Seychelles so that by 1997, it was present on three islands; Mahe, the nearby CerfIsland, and Silhouette. There were also unconfirmed reports from Praslin and LaDigue (FAO 1997).

Plant protection measures implemented have varied since the first cases of thedisease were detected. Infected trees on Praslin and La Digue were initially cut andburnt (Ivory and Andre 1994), and legal measures were adopted in 1995 to outlaw

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Table 1. Occurrence of takamaka by island (and by habitat within island) in the granitic Seychelles; allislands over 20 ha are shown. Areas of takamaka-dominated habitats (in ha) are shown where available.

Island Area (ha) Beach crest Woodland Wilt

Plateau Hill

´Mahe 15252 1 1 1 1 (1994)Praslin 2756 1 1 1 1 (1995)Silhouette 1995 1 1 1 1 (1997)La Digue 1010 1 . 70 1 1 (1995)Curieuse 286 1 28 27 1 (2000)

´ ´Felicite 268 1 2 120 2

Ste Anne 219 1 2 1 1

´Fregate 210 2 1 1 2

North 201 1 7 4 1 (1999)aCerf 127 1 1 NA 1 (1995)

Marianne 95 2 2 7 2

Grande Soeur 84 1 1 19 2

´ `Therese 74 1 2 1 1

Aride 68 2 (1) 2 2

Conception 60 2 2 1 2

Petite Soeur 34 2 2 1 2

Cousin 29 2 (1) (1) 2

Cousine 26 2 (1) 1 2aLong 21 1 2 2 1

Beach crest: 1 takamaka present, – takamaka absent or no beach crest vegetation; Plateau /Hillwoodland: 1 takamaka present, (1) takamaka present in small numbers, – no plateau /hill woodland, ortakamaka absent; Wilt: 1 wilt present (with date of first record where known), – wilt absent December

a2000. NA – no available data. Islands not visited.

the transport of takamaka timber and seedlings between islands (Shah 1995b). From1997, treatment of affected trees was limited to pruning affected limbs. Unfor-tunately, this probably aided the spread of the disease by leaving infected trees as asource of infection, and providing cut surfaces and damaged tissue for colonisationby scolytid beetles (FAO 1997). At present, sanitation is limited to the removal ofdead trees in places of visual impact or where there is a public danger, and thelimited injection of systemic fungicides (‘Storite’ and ‘Tilt’) for key amenity trees(M. Vielle in litt.).

Methods

Distribution of takamaka

In 1999 and 2000, field visits were carried out to 16 islands in the graniticSeychelles between 26 and 15252 ha in size. On each island, the presence /absenceof takamaka, and of trees showing symptoms of vascular wilt disease, were noted.For islands that were not visited, presence of takamaka and takamaka wilt disease

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were confirmed by observation from nearby islands or by consultation with islandresidents.

´ `On eight of the islands listed in Table 1 (Cousin, Conception, Therese, Grande´ ´Souer, Marianne, North, Felicite, Curieuse), maps of vegetation cover in each island

were produced from field observation and recent (1997) aerial photographs pro-duced by the Government of Seychelles, Ministry of Land Use and Habitat (GISsection). From these maps, the area of vegetation dominated by takamaka wascalculated. Vegetation plots, each 10 m 3 10 m, were randomly located inwoodland/scrub habitats (excluding open habitats such as gardens, grassland andopen rock), using 1:10000 maps (Directorate of Overseas Surveys /Government ofSeychelles) onto which vegetation distribution had been superimposed. Randomplots were located using a grid superimposed onto these maps and locationsidentified on the ground by measuring from known features. Within each vegetationplot, the dimensions (dbh [diameter at breast height], tree height) of all trees(defined by height; trees over 5-m tall) were recorded (for more details, see Hill2001).

Case studies: spread and distribution of takamaka wilt

´Detailed surveys of takamaka wilt were carried out on three islands: Mahe (15252´ha), La Digue (1010 ha) and North Island (201 ha). On Mahe, takamaka wilt was

investigated in beach crest habitat from 7th April to 13th April 2001. Twelvebeaches of 600 m or more in length were selected, distributed throughout thecoastline except along a 15-km stretch of the East coast from Victoria to theInternational Airport, an area with no natural beaches due to land reclamation. Thelength of beach crest surveyed on each beach was derived from 1:10000 maps(Directorate of Overseas Surveys /Government of Seychelles). On each beach, alltrees (woody plants and palms with stem dbh . 10 cm) in a strip 5 m deep from thetop of the shore were identified to species and dbh was recorded in 10 cm classes.For all takamaka trees, wilt was scored on a six-point wilt damage scale: 0 – nosymptoms of wilt; 1 – early symptoms of wilt: a few twigs showing characteristicfoliage loss; 2 – more extensive dieback. One or two branches showing completefoliage loss; 3 – most branches dead, only one branch or less with foliage; 4 – nofoliage; 5 – no foliage, and extensive bark loss from major stems. On one beach(North East Point, ANE), trees showed foliage damage that could not be attributedto wilt disease: here, necrosis of the margins of leaves and some foliage loss wereprobably caused by exposure to salt spray. However, symptoms typical of thedisease (Ivory et al. 1996) were noted on a subset of these damaged trees.

Where there was evidence that takamaka trees had been pruned, this was alsorecorded, as either old pruning (where pruning cuts had begun to heal) or recentpruning (where no healing had occurred). The combined total length of beaches

´assessed on Mahe was 12.8 km.´On Mahe, most lowland forest has been cleared, and there are no significant areas

of takamaka-dominated lowland forest remaining, so comparative data on thedisease in lowland (plateau) woodland were gathered on La Digue and North Island.

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On La Digue, trees were counted in the territories of Seychelles black paradiseflycatcher Terpsiphone corvina. In 29 known territories, totalling ca. 25 ha of the ca.69 ha woodland on the island’s major (western) plateau, all trees over 10 cm dbhwere identified to species; for more details, see Currie et al. (in press). The dbh class(10 cm classes) of each tree was recorded. For takamaka trees, individuals withextensive foliage loss (2 and over in the damage scale above) were recorded as aseparate category from trees with slight or no symptoms of infection.

On North Island, the number of trees with wilt was calculated by field observa-tion, walking throughout the island’s plateau woodland and counting every tree withextensive foliage loss due to the disease (2 and over in the damage scale above).

Results

Distribution of takamaka

Takamaka trees were found on all islands visited (although rarer on the smallerislands) in three main locations: (i) at the beach crest, just above the high-watermark; (ii) on coastal plateaus (flat coastal areas, mainly formed of recent corallinesediments); and (iii) in hill woodland (on granite rocks, altitudes .5 m a.s.l.).

´On Mahe, takamaka occurred on 11 of 12 beaches surveyed and was the secondmost abundant species recorded after coconut Cocos nucifera (mean percentage ofstanding takamaka trees by beach 6 1 SE 5 28.34 6 3.69; mean percentagecoconut 6 1 SE 5 36.44 6 6.03). Other species of broad-leaved trees occurred insignificantly lower numbers than takamaka; the third most abundant woody speciesrecorded was badamier or Indian almond Terminalia catappa (mean percentage ofstanding badamier trees 6 1 SE 5 8.48 6 2.51).

In plateau sites, takamaka tended to be the dominant tree species, either formingsingle-species stands or in mixed stands with badamier. Takamaka tree densities in

21 ´ `plateau woodland varied from 29 trees ha (Therese, where the tree occurred in21mixed stands) to 535 trees ha (North Island, where it was present in a dense

monospecific stand). On the western plateau of La Digue Island (study area 161 ha,of a total plateau area of approximately 220 ha), native woodland comprised ca. 69ha (Currie et al., in press). This forest showed relatively high species richness,largely due to the presence of many introduced species (in a total of 5221 individualtrees recorded, 41 species were represented, and at least 28 of these were non-native). Within the 29 flycatcher territories surveyed, takamaka was the mostabundant tree recorded; of 5221 individuals, 1751 (37.8%) were takamaka.Badamier made up 32% of total individuals. Coconut was the only other species tomake up more than 10% of the total number of trees, comprising 13.4% ofindividuals.

In hill woodland (and on islands with no coastal plateau), takamaka was lesscommon and more likely to occur in a mixture of other tree species. Under these

21conditions Takamaka tree density varied between 5 and 380 trees ha (both onMarianne Island).

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Spread and distribution of takamaka wilt

Takamaka wilt was recorded on 10 islands (Figure 1). On several islands the rate ofspread was observed to be rapid. More detailed case studies are considered below,

´i.e., beach crest trees on the island of Mahe, and trees in plateau woodlands on theislands of La Digue, North and Curieuse.

´Mahe beach crestTrees with symptoms of takamaka wilt were recorded on all 11 beaches with

Figure 1. Distribution of takamaka wilt in the granitic Seychelles. (a) Position of granitic archipelago. (b)´Main islands. Those with names in bold caps had takamaka wilt infections in 2000. (c) Mahe and satellite

islands showing spread of wilt disease 1994–1999 (data from Ivory 1994; FAO 1997). Beaches visited inthe current survey are identified by initials.

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takamaka. Overall, 521 takamaka trees observed (71% of total) were judged asshowing symptoms of takamaka wilt disease. Of these, many (48%; 248 of 521trees) showed initial symptoms (1 on the wilt damage scale), but 11% of infectedtrees (59 trees) showed complete death of aerial parts and loss of bark (5 on the wiltdamage scale) (Table 2). Trees in different size classes were differentially affected.Trees in smaller size classes were more abundant (the modal size class was 30–40cm dbh), but the proportion of trees affected was greater in larger size classes (Dmax

5 0.11, P , 0.05, Kolmogorov–Smirnov two-sample test: Siegel and Castellan1988); see Figure 2.

Many takamaka trees (143 of 731; 19.6%) showed signs of recent pruning,probably carried out to remove infected tissue. The extent of pruning varied betweentrees: frequently, entire branches were cut. Of recently pruned trees (n 5 143), only18 individuals (12.6%) showed no symptoms of wilt in remaining tissue. Themajority showed symptoms of wilt, suggesting that pruning had failed to halt thefurther spread of the disease.

La Digue plateau woodlandThe first record of takamaka wilt disease on La Digue was in 1995. However,establishment of the disease appeared rather slow, perhaps inhibited by the cuttingof infected trees; by 1999, few infected trees were present (estimated at around 1%of takamaka trees). By July–September 2000, when the surveys were conducted,225 individuals (11.9% of all takamaka trees in 25 ha plateau woodland) showedextensive wilt (.2 score).

North Island plateau woodlandThe first record of takamaka wilt on North Island was made in 1999 (Hill et al.

´Figure 2. Takamaka trees on Mahe beaches, by 10 cm dbh class. Size classes marked with an asteriskhave significantly fewer infected individuals than expected (see text).

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´Table 2. Takamaka wilt on Mahe beach crest 2001.

Beach Abbreviations Beach No. of Proportion Percent Percentlength trees per of trees takamaka takamaka(m) 100 m takamaka infected dead (scale 5)

(scale 1–5)

Anse Nord Est ANE 1350 15.93 0.37 68.75 15.00Beau Vallon BV 1740 22.41 0.46 54.49 3.37Port Launay PL 600 17.17 0.29 73.33 10.00Grand’ Anse GA 1130 21.50 0.23 85.71 25.00Anse Boileau AB 1200 13.58 0.18 63.33 6.67Anse La Mouche ALM 1280 14.14 0.25 86.96 6.52Anse Royale AR 1400 21.50 0.35 85.58 3.85Baie Lazare BL 850 26.94 0.50 77.19 4.39Anse Takamaka AT 500 19.00 0.18 35.29 0Anse Intendance AI 770 17.66 0.11 60.00 6.67Anse Marie Louise AML 1400 22.14 0.20 78.69 14.75Police Bay PB 600 5.17 0 – –Mean 1068 18.70 0.28 71.27 8.07

Abbreviations of beaches are indicated in Figure 1c.

2001), when a few trees were observed showing symptoms of wilt disease. In 2001,128 trees showing canopy death of 50% or more (wilt damage scale classes 3–5, seeabove) were recorded in plateau woodland. Estimates of the total number oftakamaka trees on the plateau range from 4723 to 10156 trees (95% confidencelimits). In January 2000, therefore, 1.3–2.7% of takamaka trees in plateau woodlandon North Island showed serious symptoms of wilt disease.

Curieuse Island plateau woodlandTakamaka wilt was recorded in January 2000, when a few trees in plateau takamakawoodland showed possible signs of the disease. By February 2001, the disease wasfirmly established in the same location, with almost all trees in a 2-ha area ofwoodland showing some symptoms of wilt disease; most had lost all foliage.

Discussion

In the granitic Seychelles, takamaka wilt appears to be both virulent and fast-spreading. Since it was first recorded in 1994, it has reached 10 islands and hascaused significant mortality of takamaka on some of these islands, the full implica-tions of which may not be realised for some time.

Spread of the disease

Takamaka wilt disease is now found on most of the larger granitic Seychelles´ ´islands. The largest island with no signs of the disease in 2000 was Felicite (268 ha),

which has extensive hill woodland dominated by takamaka. Current data indicates

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that beach crest and coastal plateau woodland are more susceptible to infection than´ `trees at higher altitudes: for example, on Therese and North Island, trees in hill

woodland showed no signs of infection in 2000, while the disease was advanced incoastal and plateau trees.

´Mortality on beach crest (Mahe) is at least 11%; this estimate is conservative, as itdoes not account for trees that had already been felled at the time of the survey in2001, and assumes that trees that have not lost significant portions of their barkretain the capacity for recovery. On La Digue, North Island and Curieuse, plateau

´woodland showed lower rates of infection than Mahe beach crest, although thedisease arrived on all these islands more recently. In plateau woodland, it appearsthat at least 10% of trees show extensive disease symptoms within 5 years of the firstarrival of the disease. Rapid spread of the disease in plateau woodland may beassociated with human activity (such as the pruning of trees), although the disease isalso well established on at least one uninhabited island (North Island).

The role of the vector Cryphalus trypanus in the spread of wilt disease isambiguous, although the species is undoubtedly capable of carrying the fungalspores from diseased trees (Wainhouse et al. 1998).

Predicting the future course of the disease in the Seychelles

It is difficult to predict the future course of the disease and its implications. While itis obvious that rates of infection, between-island movement and spread betweentrees can be rapid, the available data suggest that rates of transmission and mortalityvary between situations. Given the spread of the disease between islands to date(despite efforts to restrict its movement), it seems likely that the pathogen will occuron most of the inner islands of the Seychelles in the next few years, excluding onlythe smallest islands with little traffic and few (or no) takamaka trees. The diseasecould lead to deleterious effects on takamaka and ecosystems to parallel those ofother introduced fungal pathogens of trees; for example, Chestnut blight Cryphonec-tria (Endothia) parasitica in North America, Dutch elm disease Ceratocystis ulmiand C. novo-ulmi in Europe and North America (Gibbs and Wainhouse 1986), andPhytophora cinnamoni on Eucalyptus in Western Australia (von Broembsen 1989).

Implications for conservation in the Seychelles

Takamaka, although not endemic to the Seychelles archipelago, has a very im-portant role to play in ecosystems of the granitic islands; it is among the mostwidespread native woody plant species in the archipelago. No other tree is found inas wide a range of habitats, from beach crest to hill woodland (and no single speciescould be used in replanting all of these habitats). On beach crests, it has a role inerosion control. In all situations, it can form a large tree which casts a relatively deepshade, excluding exotic woody species. The species contributes greatly to thestructural diversity of Seychelles forests, providing fallen timber, tree hole eco-systems in addition to vegetation biomass. The loss of takamaka to vascular wiltdisease appears likely to have a range of significant effects on conservation value.

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Lowland forests are rather rare in the Seychelles, having been largely replaced bycoconut plantations in the 19th and early 20th centuries. However, where suchforests occur they are often dominated by takamaka. On La Digue, takamaka is themost abundant tree species in plateau woodland, and this is the main habitat for thecritically endangered Seychelles black paradise flycatcher Terpsiphone corvina(Watson 1981). The world population of this bird is ca. 150–200 individuals(Rocamora 1997), at least 97% of which are on La Digue. The main threat to theflycatcher on La Digue is habitat loss through housing, development for tourism,and clearance for agriculture (Collar and Stuart 1985). Takamaka wilt poses anadditional threat to the flycatcher on La Digue and may impede future conservationmeasures, since it has spread to almost all other islands in the granitic archipelagosuitable for the translocation of the species at present.

Management recommendations

Eradication of the disease now appears to be impossible. It is well established andlikely to spread to all suitable islands in the granitic Seychelles with time.Recommendations for the management of the diseased trees therefore must concen-trate on ameliorating the effects on the environment in general (erosion control) andfor associated endemic species.

Because of the tree’s role in erosion control, the importance of replanting deadtakamaka with other native trees of the beach crest (such as Hernandianymphaefolia and Cordia subcordata) has been recognised, and extensive replant-

´ing by government agencies has occurred on Mahe beaches, but not on small,inaccessible and privately owned islands.

On La Digue and islands with potential for the translocation of the Seychellesblack paradise flycatcher, the loss of coastal plateau takamaka woodland is par-ticularly important. On La Digue, replanting of affected areas of takamaka forest hasbeen slow, complicated by multiple private land ownership of much of the plateau.Increased attention to hygienic forestry practices may slow the spread of the diseasein this situation. However, more radical and proactive measures are required. Due tothe extensive distribution of the disease, the removal (or, at least, pruning for publicsafety) of dead and dying trees should be combined with underplanting of othernative trees such as Terminalia catappa, Mimusops sechellarum and Ficus spp. toensure continuation of native forest cover on plateaus. On smaller islands, con-ditions are more suitable for such a radical policy of replanting to be carried out, butthe effects of any planting carried out are unlikely to be felt for several years. If thedisease continues to spread with the rapidity of its first establishment on suchislands, there is likely to be a net loss of lowland forest on these islands for severalyears. Without such measures, the rapid loss of mature takamaka is likely to allowinvasive introduced species to become established in areas formerly dominated bytakamaka: on small islands in particular, the woody flora is often dominated byintroduced and/or invasive species (see Hill 2001).

The takamaka wilt disease is not the only recent example of an (apparentlyintroduced) fungal pathogen of trees becoming established in the Seychelles. In

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2000, a new wilt disease was discovered on the introduced sangdragon Pterocarpus´indicus (Seychelles Nation, 8th May 2000). On Fregate Island, sangdragon is an

important host for adults, and probably also the wood- and bark-feeding larvae ofthe giant tenebrionid beetle Polposipus herculeanus (Marshall 1982), an island

´endemic restricted to Fregate.The emergence of such diseases points to the importance of phytosanitary

measures regulating the import of live plants, soil and timber (especially, un-processed timber). In both cases, it appears that strict sanitation of sites after the firstarrival of the disease has been ineffective in preventing establishment and furtherspread of the disease.

In the Seychelles, as in many other small island states, imports make up a largepart of the economy and controlling the influx of species, particularly of crypticorganisms such as fungal and other pathogens, is difficult. It is therefore imperativethat measures are in place to control the establishment and spread of species oncethey arrive. Species invasions remain unpredictable events, but lessons learnt in theresponse to takamaka wilt disease might be of value in responding to futureinvasions.

Acknowledgements

The fieldwork described in this paper was carried out as part of the projectManagement of Avian Ecosystems in the Seychelles, funded by the GEF of theWorld Bank and executed by BirdLife Seychelles. The authors would like to thankall island owners and managers for cooperation with the 1999/2000 survey of thegranitic Seychelles, especially Kevin Hoareau on Curieuse and John Etienne on

´ `Therese, who both provided useful information on the disease locally. Areas oftakamaka forest were calculated from data supplied by Ministry of Land Use andHabitat, Seychelles. The Director of the Forestry section of the Ministry ofEnvironment and Transport of the Government of Seychelles, Mr Michel Vielle,provided a useful insight on the government response to the disease. Both Dr CliveHambler and Dr Jaboury Ghazoul provided invaluable comments on early drafts ofthis manuscript.

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