allen 2008

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS

Aquatic Conserv: Mar. Freshw. Ecosyst. 18: 541–556 (2008)

Published online 24 August 2007 in Wiley InterScience(www.interscience.wiley.com) DOI: 10.1002/aqc.880

Conservation hotspots of biodiversity and endemismfor Indo-Pacific coral reef fishes

GERALD R. ALLEN*Department of Aquatic Zoology, Western Australian Museum, Locked Bag 49, Welshpool DC, Perth 6986, Australia

ABSTRACT

1. Distribution patterns of 3919 species of Indo-Pacific reef fishes were analysed using GISmapping software for the purpose of conservation prioritization of extraordinary highconcentrations (‘hotspots’) of diversity and endemism.2. Megadiversity countries with more than 1000 coral reef species include Indonesia, Australia,

Philippines, Papua New Guinea, Malaysia, Japan, Taiwan, Solomon Islands, Palau, Vanuatu, Fiji,New Caledonia, and the Federated States of Micronesia.3. The richest area for reef fishes is the renowned Coral Triangle, which includes eastern Indonesia,

Sabah (Malaysia), Philippines, Papua New Guinea, and the Solomon Islands. The highestconcentration of species within this region extends from south-eastern Indonesia to the centralPhilippines.4. Occupying only 3% of the surface area of the tropical Indo-west and central Pacific, the heart of

the Coral Triangle contains 52% of its total species.5. The top-ranked areas based on percentage of endemism are Easter Island, Baja California,

Hawaiian Islands, Galapagos Islands, Red Sea, Clipperton Island, Marquesas, Isla del Coco,Mascarene Islands, and Oman.6. The highest concentration of endemics per unit area occurs at remote south-eastern Polynesian

and eastern Pacific islands including Clipperton, Isla del Coco, Easter, Rapa, and the PitcairnGroup.Copyright # 2007 John Wiley & Sons, Ltd.

Received 2 October 2006; Revised 6 May 2007; Accepted 12 May 2007

KEY WORDS: species richness; zoogeography; GIS analysis; coral triangle; marine protected areas

INTRODUCTION

Hotspot is a term frequently used by conservation biologists to denote a relatively restricted geographicarea containing an extraordinary high concentration of biodiversity and endemism. The hotspot concept

*Correspondence to: Gerald R. Allen, Department of Aquatic Zoology, Western Australian Museum, Locked Bag 49, Welshpool DC,Perth, Western Australia 6986. E-mail: tropical [email protected]

Copyright # 2007 John Wiley & Sons, Ltd.

has been especially effective for prioritizing conservation action when faced with the enormous task ofbiodiversity conservation with limited financial resources (Mittermeier et al., 1998, 1999). Until recently,the concept has been applied primarily to terrestrial systems. For example, Myers et al. (2000) recognized25 global hotspots based on the number of endemic plants and non-fish vertebrates, their area ratios, andthreats as indicated by natural habitat loss.

Conservation International is currently developing a global conservation strategy that recognizes theimportance of marine hotspots with special emphasis on coral reef areas. Although it is generally acceptedthat tropical latitudes support the Earth’s greatest marine biodiversity, knowledge is far from complete forany region. Considering the huge unfilled gaps of taxonomic information for many groups, particularlyinvertebrates, it is convenient to use well known ‘flagships’ as indicators of general biodiversity. Fishes areparticularly useful in this regard for several important reasons. First and foremost they are highly specioseand exhibit a full range of distribution patterns from wide-ranging circumglobal species to highly restrictedlocal endemics. Unlike most groups of marine organisms the majority of species are easily observed in thefield and by comparison their taxonomy and distribution patterns are relatively well studied. Importantly, ithas been shown in a number of studies that there is a strong local correlation between fish diversity anddiversity of other organisms such as molluscs (Wells, 2002) and corals (Veron, 2000).

Birds have been similarly used to rally conservation support for terrestrial areas subjected to habitatdegradation (Stattersfield et al., 1998). Like their avian counterparts, fishes are finely adapted to acombination of environmental factors, of which the availability of food and shelter are particularlyimportant. Therefore, the local or regional reef fish community is a useful gauge of both habitat and overallbiodiversity. A typical coral reef supports a wealth of fishes, which in turn depend on a complex food webinvolving myriad plants and invertebrates (Sale, 1991).

Roberts et al. (2002) were the first authors to embrace the idea of global marine hotspots. Their analysiswas based on the distribution patterns of 1700 species of reef fishes, 804 species of coral, 662 species ofmolluscs, and 69 species of lobster. The data were used to rank various centres of endemism, mainly on thebasis of concentration of restricted-range endemic species. They recognized 18 hotspots ranging in size fromtiny Easter Island in the south-eastern Pacific to the entire Great Barrier Reef of Australia. However, theirmethodology was questioned by Baird et al. (2002), who emphasized the need for a more balancedapproach that does not rely so heavily on the concept of endemism at the expense of overall biodiversity.Moreover, despite the apparently large number of species utilized for the analysis, it was a global studybased on insufficient numbers from the species-rich Indo-Pacific region. In addition, there have beenconsiderable advances in our knowledge of fish distributions and geographical information systems (GIS)since their data were gathered.

Allen (2002) used coral reef fishes as indicators of marine conservation hotspots based on distributionpatterns of Indo-Pacific coral reef fishes. The analysis involved general diversity as well as endemism basedon absolute numbers, percentage of endemics, and concentration of endemism according to area size. Thepresent study provides an expansion of these same ideas, but employs a more rigorous GIS approach and aconsiderably expanded dataset.

The ultimate goal of the present analysis is to identify concentrations of diversity and endemism (i.e.hotspots), at varying spatial scales, as an aid for prioritizing marine conservation initiatives. This isaccomplished by utilizing a dataset that includes distribution maps of every known species of coral reef fishin the Indo-west and central Pacific. Special emphasis is placed on the Coral Triangle region of South EastAsia, an area that supports the greatest global marine biodiversity, but is also among the most threatened(Allen and Werner, 2002; Briggs, 2005).

Terrestrial hotspots as previously defined (Myers et al., 2000) are generally areas of exceptional diversity/endemism that are also highly threatened. However, the current analysis of reef hotspots purposely avoidsinclusion of a threat layer. It is acknowledged that coral reefs of certain regions (e.g. South East Asia) areparticularly threatened by an extremely high density of human inhabitants and consequent effects of fishing

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Copyright # 2007 John Wiley & Sons, Ltd. Aquatic Conserv: Mar. Freshw. Ecosyst. 18: 541–556 (2008)

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pressure and careless land use, but virtually all coral reefs are currently at risk. Certainly the most ominousthreat is the disturbing trend of accelerating ocean temperature and the periodic severe coral bleachingevents they promote (Hoegh-Guldberg, 1999).

Although GIS techniques are employed to analyse the data, this study is strongly influenced by theauthor’s Indo-Pacific field experience, totalling more than eight years (i.e. about 4.5 months per year) over a35 year period, with special focus on the taxonomy, ecology, and zoogeography of the region’s reef fishes.The past decade was particularly instructive, involving multiple journeys to Fiji, Madagascar, Indonesia,and Papua New Guinea as well as extended single visits to western Thailand, Philippines, Christmas Island(Indian Ocean) Solomon Islands, and the Phoenix Islands.

METHODS

The study is restricted to shallow reef fishes, which are herein defined as species that are entirely or mainlyconfined to coral reefs and intermingled substrata (sand/rubble patches, seagrass beds, etc.) less than 60mdeep. The 60m depth limit is near the lower limit of scuba diving, and also approximates the limit of mostreef-building scleractinian corals (Veron, 2000).

Distribution patterns of 3919 species of reef fishes were analysed to provide more accurate information toset conservation priorities. A distribution map was prepared for every known species of reef fish in thetropical Indo-west and central Pacific from East Africa and the Red Sea to the islands of Oceania.Distribution polygons, bounded by the outermost records of occurrence, were drawn on standard equal-area base maps utilizing ArcView GIS software. The distribution of individual species was represented as asingle polygon if numerous collection/visual observation records indicated a more or less continuousdistribution (Figure 1). However, for species that appear to have a genuine disjunct distribution or arepoorly known and reported from a relatively few scattered locations, two or more polygons or circles wereused (Figure 2). The latter category accounts for approximately 40% of the total species. These types ofdigitized polygons are commonly employed by taxonomic specialists to convey overall distribution patternsfor a diverse range of shallow marine taxa from seaweeds and corals to marine mammals (Carpenter andNiem, 1998–2001; Veron, 2000). Although polygons show broad expanses of deepsea/pelagic habitat, theyare constructed on the premise that the species in question occurs within the boundaries only where suitablehabitat (e.g. shallow coral reefs) is present.

Polygons rather than point distribution records based on actual museum specimens were utilized in orderto expedite the completion of the project within a 3 year period. Essentially, the same information (i.e.hotspot delineation) is generated with polygons as with the extremely labour intensive point data. Actualmap preparation involved between 5 and 60min per species, depending on the complexity of thedistribution.

An accompanying database containing family, genus, and species names, as well as the author(s) andyear of publication was prepared with an Excel spreadsheet. The integration of maps and spreadsheetfacilitated production of various analytical programs that generated instantaneous listings of either totalfauna or total endemics for any polygon, regardless of size, circumscribed on the ArcView basemap.

Distribution data were gathered from a variety of sources including personal observations throughoutthe Indo-Pacific over the past three decades, recent literature (new species descriptions and especially familyand generic revisions), regional faunal monographs, collections and collaboration of numerous colleagueswho are mentioned in the acknowledgement section. In addition, collections from the following museumswere utilized: Australian Museum (Sydney), Bishop Museum (Honolulu), California Academy of Sciences(San Francisco), National Museum of Natural History (Washington, DC), and the Western AustralianMuseum (Perth).

CONSERVATION HOTSPOTS FOR INDO-PACIFIC CORAL REEF FISHES 543


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Figure 1. Distribution of Abudefduf bengalensis (Pomacentridae).

Figure 2. Distribution of Discordipinna griessingeri (Gobiidae).

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Reef areas expressed as km2 for various countries in Table 1 were obtained from theWorld Atlas of CoralReefs (Spalding et al., 2001). Apparently there are no reliable figures available for reef areas of most smalloceanic islands. Therefore, the locations listed in Table 5 were estimated by multiplying the island(s)perimeter in km by 0.5. The multiplier represents the maximum distance from shore (500m) for mostshallow coral reefs at typical island locations as determined by satellite imagery on the NASA world widewebsite. The figure assumes there is a uniform belt of coral/rocky reef habitat, which of course is not theactual case and many reefs that fringe oceanic islands are narrower than 500m. Therefore, the estimates areprobably higher than the actual reef area for most of the listed locations.

Although the tropical eastern Pacific was not included in the current mapping project, data fromprevious studies by the author and D.R. Robertson (Allen and Robertson, 1994) were utilized, particularlywith reference to the analysis of endemic species per unit area.

RESULTS

Analysis of species diversity

The pattern of diversity for reef fishes presented in Figure 3 is compatible with that of marine invertebratesthat have been well documented including corals (Veron, 2000) and molluscs (Wells, 2002), and probably isapplicable to other major invertebrate groups. Basically, the centre of diversity extends from centralIndonesia to Papua New Guinea and the Solomon Islands, and northward to the Philippines. This region(delineated by the darkest shade in Figure 3) is frequently referred to as the Coral Triangle by conservationbiologists and is the globe’s richest area for marine biodiversity (Allen and Werner, 2002). There is generalfaunal attenuation in all directions from the centre, although this trend is less pronounced towards the westwhere there is an increase in diversity in the Red Sea and south-western Indian Ocean. Numerous familiesof reef fishes exhibit similar patterns, for example well-studied groups such as Pomacentridae and Labridae,which contain 302 and 361 species respectively in the Indo-west and central Pacific region.

Conservation activity is usually implemented at the country level or regional level involving adjacentcountries. It is therefore useful to rank individual countries on the basis of overall species diversity. Thecountries with the highest diversity of reef fishes, the exclusive ‘1000 species club’, are indicated in Table 1.

Table 1. Countries with more than 1000 coral reef fishes including percentage of the total reef fish fauna of the Indo-west and centralPacific region (IWCP), estimated coral reef area, density based on the number of species per km2, and number of endemics

Country Species Percent IWCP spp. Reef Area (km2) Spp./km2 Endemics

Indonesia 2122 54.4 51 020 0.042 78Australia 1827 46.8 48 960 0.037 93Philippines 1790 45.9 25 060 0.071 29Papua New Guinea 1635 41.9 13 840 0.118 22Malaysia 1549 39.7 3600 0.430 1Japan 1462 37.5 2900 0.504 26Taiwan 1374 35.2 940 1.462 7Solomon Islands 1371 35.2 5750 0.238 3Republic of Palau 1254 32.2 1661 0.755 3Vanuatu 1105 28.3 4110 0.269 2Fiji 1068 27.4 10 020 0.107 15New Caledonia 1060 27.2 5980 0.177 7Federal States of Micronesia 1031 26.4 4340 0.238 7



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In terms of density of reef fish per unit area, Taiwan and Palau lead all other megadiversity countries due totheir comparatively small reef area and rich fauna, which share many elements with the nearby CoralTriangle. Isolated oceanic islands generally have rich concentrations of reef fishes. For example, the tinyisland nation of Nauru in the western Pacific, with a coral reef area of less than 4 km2, has an exorbitantdensity of 177 species/km2.

The Indonesian Archipelago is the world’s premier area for marine biodiversity, mainly due to itsextraordinary wealth of coral reef organisms. Allen and Adrim (2003) recorded 2056 species fromIndonesia, and the total of 2122 species recorded during the present study confirms its position as therichest country in the world for reef fishes. There is, however, considerable conjecture concerning thelocation of the highest concentration of species within the Coral Triangle.

According to Carpenter and Springer (2005) the ‘centre of the centre’ for fish diversity is situated in thecentral Philippines, with a secondary area of high diversity located off north-eastern Sumatra. Utilizingsimilar methodology as the present study, their conclusions were based on GIS mapping overlays for 2983marine organisms, including 2047 shore fishes. However, unlike the current study, which involves coral reeffishes, they utilized mostly common fisheries species (including a high percentage of soft-bottominhabitants), excluding numerous small reef fishes that tend to have more restricted ranges. Less than halfof the species included in their analysis were coral reef inhabitants. The distributions were mapped by 84taxonomic specialists for a Food and Agriculture Organization of the United Nations publication(Carpenter and Niem, 1998–2001). Their analysis was based on comparisons of single 10 km � 10 kmpixels (i.e. 100 km2 area).

Surprisingly, considering the discrepancy in the nature of the databases, the present results corroborate thefindings of Carpenter and Springer. The highest total } 1627 species } within a limited area (100 000km2)was in the central Philippines (Figure 4), followed by the Raja Ampat Islands (1613 species), Molucca Islands(1573 species), northern Sulawesi (1567 species), and the southern Philippines (1566 species).

However, if the area of comparison is increased to a 500 000 km2 grid (Figure 5), there is a shift in thecentre of diversity to the Indonesian region between the extreme western end of New Guinea and northern

Figure 3. Map of the Indo-Pacific region showing diversity isopleths for tropical reef fishes. The lightest shade represents between 200and 400 species and the darkest shade between 1300 and 1700 species.

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Sulawesi (1705 species), followed by the Sulu Sea (1660 species), central Philippines (1648 species),southeast Banda Sea (1635 species), Lesser Sunda Islands (1628 species), and central Sulawesi (1577species).

Most importantly, the GIS-species distribution data reveal that the ‘heart’ of the Coral Triangle extendsfrom south-eastern Indonesia to the Philippines (Figure 6). This corresponds with the 1500 species contourand within this area species numbers fluctuate narrowly over a range of about 100 species. Realistically, anyarea within this region could be expected to yield a record-breaking species count given an intense collectioneffort and provided the full range of reef habitats is present. The heart region occupies about three millionkm2 or only 3% of the surface area of the tropical Indo-west and central Pacific, yet it contains 52% of thetotal species from this vast region. Randall (1998) proposed several key factors for the proliferation of reefspecies in the region including its complex geological history with merging of disparate elements due totectonic shifting, the ‘stepping-stone’ nature of the archipelago that tends to prevent local extinctions, a

Figure 4. Comparison of faunal totals for 100 000 km2 squares superimposed on Coral Triangle region of Southeast Asia.

Figure 5. Comparison of faunal totals for 500 000 km2 squares superimposed on Coral Triangle region of Southeast Asia.



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long history of stable climate, periodic raised/lowered sea levels that form isolating barriers, and itsstrategic position between the Pacific and Indian Ocean.

Although 1500 species appears to be the hallmark of a localized (under 100 000 km2) area within the heartof the Coral Triangle, this figure has never been documented in the field. It is based on a combination ofcollection/visual observation records and expected range distributions records. The highest actual totals forthe region based on localized field surveys by the author between 1985 and the present time were obtainedat the Raja Ampat Islands, western New Guinea (1119 species), Maumere Bay, Flores (1111 species), andMilne Bay Province, Papua New Guinea (1109 species).

The Great Barrier Reef of Australia, although lying just beyond the boundary of the Coral Triangle, isnevertheless one of the globe’s megadiversity centres for marine organisms. Spanning 14 degrees of latitudeand a linear distance of more than 1800 km, the GBR is home to nearly 1500 reef fishes, including 34endemics. Western Australia is also relatively rich with nearly 1400 species of tropical reef fishes, including27 endemics.

The current analysis does not support Carpenter and Springer’s (2005) finding that a secondary centre ofdiversity is located between peninsular Malaysia and Sumatra, centred on Bintan Island, lying 38 km south-east of Singapore. This is certainly invalid for coral reef fishes, where a 100 000 km2 overlay of the same areacaptures a comparatively modest total of 771 species. Reef development is poor due to an unusually highlevel of sedimentation. The author’s impression of the area, based on a week-long scuba diving survey atBintan in May 1997, was of a highly impoverished fauna, more akin with species-poor reefs of the

Figure 6. The heart of the Coral Triangle.

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Kimberley coast of north-western Australia. Moreover, M. Erdmann (personal communication) spent eightmonths in the area and documented a similarly impoverished stomatopod fauna consisting of only threespecies, in contrast to totals ranging between 23 and 36 species for localities in eastern Indonesia.

Analysis of endemism

The largest definable endemic units are consistent with the major biotic realms that are universallyrecognized (Briggs, 1974): Indian Ocean, Western Pacific, and Pacific Plate (Figure 7).

Although not part of the present analysis, the eastern Pacific region possesses a highly unique fauna,which is more closely related to that of the western Atlantic. This relationship reflects a common ancestryresulting from the interconnection of the two areas prior to final closure of the Panamanian land bridge,which occurred about 3.1 million years ago (Coates and Obando, 1996). Few species are common to boththe West Atlantic and East Pacific, but numerous genera and sister-species are shared (Allen andRobertson, 1994).

The reef-fish fauna of the Indo-west and central Pacific is remarkably homogenous at family and genericlevels. There are also numerous wide-ranging species that occur in two or more of the major realms.However, the present analysis is primarily concerned with species that are confined to one of the majorrealms or exhibit more restricted ranges.

Both West Pacific and Indian Ocean realms are characterized by relatively high levels of endemism withapproximately one endemic for every 3–4 species in the respective areas (Table 2). Although the level ofendemism for the Central Pacific is considerably less, this analysis supports the findings of Springer (1982),who recognized the Pacific Plate as a discrete sub-unit of the Indo-Pacific region.

Tables 3–5 present a listing of globally significant areas for reef fish endemism based on three differentcriteria: absolute numbers, percentage of the overall fauna, and number of endemics per unit area. Most ofthe locations indicated in Table 3 are well known for their extraordinary high levels of endemism (Randall,1998), but several have received minimal attention. For example, the Marquesas were omitted by Robertset al. (2002) in their summary of marine hotspots. These islands harbour a wealth of endemics, recentlyhighlighted by Randall (2005). Similarly, the Lesser Sunda Islands of Indonesia and coastal Oman have

Figure 7. Major biotic realms of the tropical Indo-west and central Pacific region.



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recently emerged as significant centres (Randall, 1995; Allen and Adrim, 2003). There is strong justificationfor uniting Fiji and Tonga into a single area of endemism based on a nucleus of species that are shared bythe two countries. Similarly, analysis of the Papua New Guinea–Solomon Islands region reveals asignificant number of shared elements. Their close geographic relationship is also indicative of a naturalfaunal unit.

The Bird’s Head Peninsula of Indonesia, occupying the extreme western end of the island of New Guineais perhaps the most obscure location on the list. Currently 20, mainly undescribed taxa are believed to be

Table 2. Comparison of reef fish diversity and endemism for major biotic realms of the Indo-west andcentral Pacific region

Realm Total spp. Endemics Endemism (%)

Indian Ocean 2086 532 25.5West Pacific 2989 938 31.4Central Pacific (Plate) 1403 130 9.3

Table 3. Highest ranked areas in Indo-west and central Pacific region based on total number ofendemic reef fishes

Location Endemic spp. Total spp.

Hawaiian Islands 86 420Mascarene Islands 37 819Marquesas Islands 36 507Great Barrier Reef 34 1455Fiji–Tonga Islands 29 1115Western Australia 27 1302Northern Red Sea 26 778Lesser Sunda Islands 25 1682Papua New Guinea-Solomon Islands 25 1680Southern Japan 24 1466Oman 22 581Easter Island 20 87Bird’s Head Peninsula, Indonesia 16 1230Central Philippines 14 1653

Table 4. Highest ranked areas based on percentage of endemic reef fishes

Locality Number of species Number of endemics Endemics (%)

Easter Island 87 20 23.0Baja California 400 80 21.6Hawaiian Islands 420 86 20.5Galapagos Islands 300 35 11.7Red Sea 861 95 11.0Marquesas Islands 507 36 7.1Clippperton Island 103 8 5.8Isla del Coco 192 10 5.2Mascarene Islands 836 37 4.4Oman 581 22 3.8

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restricted to this area and current research by the author and M. Erdmann will most likely increase thistotal. Within this area, Cenderawasih Bay (due south of the islands of Biak and Yapen), is particularlynotable, harbouring at least six endemics. Allen and Erdmann (2006) hypothesized that the bay wasessentially isolated for a substantial period over the past five million years and present day geographic andoceanographic conditions continue to provide a degree of isolation.

Table 4 provides a list of the 10 highest ranked hotspots for endemic reef fishes based on the percentageof the overall fauna. Easter Island with 23% endemism heads the list in this category and the majority ofother locations are relatively remote oceanic outposts where speciation has occurred due to reduced geneflow from outlying areas.

Isolated oceanic islands are also the highest ranked locations in terms of the number of endemic fishes perunit area (Table 5). Clipperton Island in the eastern tropical Pacific easily heads the list. This tiny atoll, witha shallow reef area of only 13 km2 has an impressive total of six endemics (Robertson and Allen, 1996; Allenand Robertson, 1997).

Numerous species are known on the basis of only a few specimens collected at a single location andtherefore provisionally qualify as local endemics. If known only from isolated oceanic locations there is anexcellent chance their status as a localized endemic is valid in contrast to regions where there are more orless continuous reef areas (e.g. Southeast Asia). In the latter case, the endemic status must be viewed withsuspicion until confirmed or denied by considerable collecting/observation effort in adjacent areas.

Fishes from tiny oceanic islands such as Malpelo, Clipperton, and Easter, possess some of the smallestknown ranges for tropical reef fishes. For example, the wrasse species Halichoeres malpelo (Allen andRobertson, 1992) occupies an area of less than 12 km2. Restricted-range endemics from non-oceanic areasgenerally have more extensive distributions. One of the smallest known ranges in the latter category is thatof the pomacanthid angelfish Chaetodontoplus vanderloosi (Allen and Steene, 2004), which is confined to anarea of cool-upwelling in south-eastern Papua New Guinea occupying less than 250 km2. Even thedistribution of the popular aquarium fish Pterapogon kauderni (Apogonidae), which occupies about17 000 km2 off the eastern coast of Sulawesi, is considered to be extremely small compared to that of mostreef fishes (Allen and Steene, 1995; Allen, 2000).

DISCUSSION

Many of the hotspots identified by this study have already received considerable conservation attention bylocal non-governmental organizations (NGOs) or large global organizations such as Conservation

Table 5. Highest ranked locations for endemism based on the number of endemic fishes per km2 of coral reef habitat

Locality Area (km2) Number of endemics Reef area (km2) Endemic spp./km2

Clipperton Island, E. Pacific 13 6 4 1.5Isla del Coco, E. Pacific 37 10 12 0.83Easter Island 253 20 33 0.61Malpelo Island, E. Pacific 12 3 6 0.50Rapa 91 7 28 0.25Pitcairn Islands 80 4 24 0.16Christmas Island, Indian Ocean 230 2 34 0.06Komodo Islands, Indonesia 1600 6 217 0.03Reunion 3500 3 103 0.03Mauritius 2800 12 870 0.01



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International (CI) and The Nature Conservancy (TNC). The latter two American-based organizations havebeen particularly active in critical conservation areas throughout the Coral Triangle. Much of their effort isfocused on Indonesia and the Philippines, two megadiversity centres that share an acute need for urgentconservation measures. Both countries have experienced a rapid decline in marine resources, particularlyover the past three decades. Much of the blame is attributed to the widespread use of illegal fishingmethods, of which cyanide and explosives are among the most destructive to reef environments. McAllister(1988) conservatively estimated that 75 000 kg or 1500 drums of cyanide were being sprayed onto Philippinecoral reefs each year.

The insatiable oriental market for shark fins and live reef fishes has seriously depleted stocks of groupers(Serrandiae) and other large fishes throughout the Coral Triangle. One of the prime targets of theAsian-based live restaurant fish trade is the Napoleon wrasse (Cheilinus undulatus), one of the largestspecies of reef fish, growing to well in excess of 100 cm. Young fish (under about 50 cm) are generallytargeted because they are easier to ship and market. The author has noticed an appreciable decline in thisspecies since his first visit to Indonesia in 1974. Indeed, data gathered on recent biological surveys in theCoral Triangle indicate that it is rare or absent at most locations (Table 6). This species is now listed inAppendix II of CITES, but illegal trade will no doubt continue as long as the huge demand remains on theAsian market.

Conservation hotspots are not necessarily the sole domain of the megadiversity ‘heavyweights’highlighted in Table 1. Aside from a few regional pockets of endemism within the species-rich CoralTriangle, this study supports the contention of Hughes et al. (2002) that centres of high species richness andcentres of high endemism are generally not concordant. Therefore, a two-pronged strategy embracing bothdiversity and endemism is essential to the design of any broad-scale marine protected area (MPA) network.Moreover, due to the vagaries of marine dispersal it is vital for all countries throughout the Indo-Pacificregion to work together towards the common goal of conserving biodiversity. Unlike terrestrial systemswhere restricted-range species are an important component of local diversity, marine systems arecharacterized by prodigious numbers of wide-ranging species. The current analysis reveals an average rangeof 9,357,070 km2 for Indo-central Pacific reef fishes or roughly the size of China. Approximately 40% ofspecies have geographic ranges spanning more than 10,000,000 km2. Even so called limited-range endemicshave distributions that frequently cross political boundaries, requiring multi-national conservationinitiatives. In general, limited-range marine endemics occupy much larger areas than their terrestrialcounterparts, with the exception of those confined to tiny oceanic islands. Reef fishes of the Indo-west andcentral Pacific occupying an area of less than 120,000 km2 or 10.8% of the total species are justifiablyclassed as having restricted distributions and therefore merit conservation attention.

The endemic centres listed in Tables 3–5 can justifiably share the conservation limelight withmegadiversity areas. Oceanic islands and archipelagos are particularly strong centres of endemism.Genetic studies of reef fishes currently in progress by the author and collaborators from Boston Universityindicate that island endemism may be considerably more prevalent than formerly believed. For example,

Table 6. Frequency of Napoleon wrasse (Cheilinus undulatus) for various locations in the Coral Triangle (G. Allen data)

Location Number of siteswhere seen

Percentage oftotal sites

Approx.number seen

Raja Ampat Islands } 2002 9 18.0 14Raja Ampat Islands } 2001 7 15.55 7Halmahera (southwest) } 2005 4 14.8 4Togean/Banggai Islands } 1998 6 12.76 8Calamianes Is., Philippines } 1998 3 7.89 5Weh Island, Sumatra } 1999 0 0.00 0

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recent DNA analysis reveals that six populations from Fiji previously considered as geographic colourvariants of wide ranging species are genetically distinct lineages.

Although there is only one case involving the recent extinction of a reef fish (Ferreira et al., 2005), coralreefs are increasingly at risk. Coral bleaching, elevated sea temperatures, destructive fishing practices, andsedimentation due to careless logging or agricultural practices are among the most obvious threats. There isan urgent need to establish a network of MPAs throughout the Indo-Pacific and other tropical seas. Thereis still much to learn about life history cycles of reef fishes and especially ‘source–sink’ relationships ofmarine larvae, but if we wait for researchers to provide this information it may already be too late for manyspecies. It would be far better to implement a network of MPAs as soon as possible.

A logical strategy would be to establish MPA networks focused on the 14 key endemic areas listed inTable 3. This plan would not only provide a refuge for 415 limited range endemics, but if carefully designedcould also provide a measure of protection for up to 82% of the total reef fish species in the Indo-west andcentral Pacific region. Admittedly, this plan may sound over-simplified, especially in light of the argumentthat most existing MPAs are too small and too far apart to effectively maintain genetic connectivity(Rodrigues and Gaston, 2001). However, such a network would provide a strategic foundation for futureMPA expansion that will be necessary once critical information on genetic connectivity is revealed.Moreover, there is increasing evidence (Jones et al., 2005) for highly localized self-sustaining recruitment inreef fish populations. For example, Jones et al. (1999) estimated that 15–60% of juvenile damselfish(Pomacentrus amboinensis) self-recruited back to their natal population at Lizard Island on the GreatBarrier Reef. Accordingly, Leis (2002) suggested the geographic size of management-conservation units isprobably much smaller than previously thought, perhaps on the scale of 10 s of km2.

The Bird’s Head region (far western New Guinea) of Indonesia provides an excellent working example ofhow grass roots conservation is being implemented in one of the key areas in Table 3. Major biologicalassessment surveys conducted by CI (McKenna et al., 2002) and TNC (Donnelly et al., 2003) confirmed thisregion as an exceptionally rich corridor for both diversity and endemism. The urgent establishment of anMPA network was recommended to appropriate local and national agencies on the basis of the rapidassessment findings. Over the following four-year period government officials, in consultation with localand international NGOs, formulated a strategic network of seven MPAs (Figure 8), occupying a totalsurface area of approximately 6540 km2, scheduled for implementation in mid-2007. The combination of

Figure 8. Map of the Bird’s Head Peninsula of western New Guinea showing proposed MPA network (shaded areas on main map).Abbreviations as follows: CB } Cenderawasih Bay; RA } Raja Ampat Islands; TB } Triton Bay.



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the seven Raja Ampat MPAs, an existing national park in Cenderawasih Bay and a proposed MPA atTriton Bay will provide a refuge for 1264 species of reef fishes, including at least 20 suspected endemics. TheBird’s Head conservation initiative represents an important addition to an Indo-Pacific network thatcurrently includes major MPA networks on Australia’s Great Barrier Reef (347 800 km2) and thenorth-western Hawaiian Islands (362 580 km2). Hopefully, the remaining 10 regions listed in Table 3 willinitiate similar action.

The current analysis of reef fish distributions provides crucial baseline information for prioritizingconservation initiatives in the speciose Indo-west and central Pacific region. The next logical step is toexpand the database to include the eastern Pacific and Atlantic oceans in order to provide a truly globalperspective. The maps generated in this study can also be utilized in the IUCN Red List assessment process,which is currently commencing for Indo-Pacific coral reef fishes. Because there is a general scarcity of basicinformation pertaining to abundance and past population trends, range size will assume extra importancein determining the vulnerability of many reef fishes.

ACKNOWLEDGEMENTS

The mapping study and GIS analysis was funded by Conservation International (CI). I am particularly indebted toRoger McManus, Director of Global Marine Programs at CI for his encouragement and support of this project. RobertWaller, formerly employed by CI’s GIS laboratory, designed and implemented the analytical programs. Additionaltechnical support was provided by GIS laboratory staff John Musinsky and Erica Ashkenazi. I am also grateful to TimWerner and Sheila McKenna, past and present directors of CI’s Rapid Assessment Program (RAP) for providing fieldopportunities for me that helped to fill critical gaps in the distribution data.I thank the following ichthyological specialists for contributing their distributional knowledge of specific families

and/or strategic geographic locations: Hans Bath (Blenniidae), Kent Carpenter (Caesionidae and Lethrinidae), HowardChoat (Scaridae), Bruce B. Collette (Belonidae, Hemiramphidae, and Scombridae), Tom Fraser (Apogonidae), OferGon (Apgogonidae), Hans Fricke (Callionymidae and Tripterygiidae), Anthony Gill (Pseudochromidae), DavidGreenfield (Holocentridae and Fiji), Martin Gomon (Labridae), Douglass Hoese (Gobiidae), Phillip Heemstra(Serranidae and western Indian Ocean), Barry Hutchins (Monacanthidae), Jeff Johnson (Haemulidae), Leslie Knapp(Platycephalidae), Helen Larson (Gobiidae), Peter Last (Carcharhinidae and Dasyatidae), Jeff Leis (Diodontidae),Rudie Kuiter (Syngnathidae and Indonesia), John McCosker (Muraenidae and Ophichthidae), Scott Michaels(Hemiscyllidae), Randy Mooi (Plesiopidae), Phillip Munday (Great Barrier Reef and Papua New Guinea), TheodorePietsch (Antennariidae), Richard Pyle (Pomacanthidae), John Randall (Mullidae, Labridae, Scaridae, Acanthuridaeand numerous Indo-Pacific localities), Ross Robertson (tropical Eastern Pacific), Barry C. Russell (Nemipteridae),Werner Schwarzhans (Bythitidae), William Smith-Vaniz (Carangidae and Opistognathidae), Victor Springer(Blenniidae), Jeffrey Williams (Blenniidae and Trypterygiidae), Richard Winterbottom (Gobiidae and Vietnam), andDavid Woodland (Siganidae). Finally, I express my sincere thanks to John Briggs, Kent Carpenter, Roger McManus,Russell Mittermeier, and Victor Springer, who critically reviewed the manuscript and offered helpful suggestions for itsimprovement.

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