16. LITTLE CAYMAN: ECOLOGY AND SIGNIFICANCE D.R. S toddar t In t roduct ion In t h i s f i n a l paper I wish t o emphasize some of the conclusions drawn by con t r ibu to r s t o t h i s r e p o r t , consider some of the gaps i n our knowledge of the ecology of L i t t l e Cayman, and p lace what we now know of the fauna and f l o r a i n a wider Caribbean con tex t , The purpose of t h i s Expedition has been t o provide t h e Cayman I s l ands Government, and through them the wider s c i e n t i f i c community, with b a s i c d a t a on which f u t u r e development proposals can be evaluated. I t i s no t the purpose of t h i s concluding d iscuss ion t o comment on any p a r t i c u l a r s e t of development proposa ls , b u t it i s never the less poss ib l e t o draw a t t e n t i o n t o a spec t s of t h e ecology of L i t t l e Cayman which a r e of high i n t r i n s i c importance and which a r e a l s o p o t e n t i a l l y a t r i s k of d is turbance o r des t ruc t ion . The fauna of the Cayman I s l ands i s dominantly Greater An t i l l ean , and e s p e c i a l l y Cuban, i n i t s r e l a t i o n s h i p s and de r iva t ion . This i s now well-documented f o r t he i n s e c t s , e s p e c i a l l y the b u t t e r f l i e s (H'K. Clench 1964, S c o t t 1972, Askew, t h i s volume) , and the land b i r d s (Diamond, t h i s volume), i n both cases the main a f f i n i t y being with Cuba and t o a l e s s e r e x t e n t with Jamaica. S imi l a r ly the r e p t i l e s a r e of Cuban (Anolis, Cyclura) o r Jamaican ( A r i s t e l l i q e r , Diploglossus, Sphaerodactylus, Alsophis, Tropidophis) a f f i n i t y (Grant 1940, Savage 1966, Schwartz and Thomas 1975). Of the 48 recorded spec ies of Cayman I s l ands land molluscs, 30 a r e endemic, and 17 of these a r e r e l a t e d t o Jamaican spec ie s , 10 with Cuban, 1 with the I s l e s of Pines, and 2 with Cent ra l America ( W . J . Clench 1964); P i l s b r y ' s (1930) inference of a former land connection wi th Jamaica cannot now be sus ta ined (Thompson 1974). Both t h e fauna and the f l o r a of L i t t l e Cayman have presumably been der ived from the Greater A n t i l l e s by chance d i s p e r s a l , and it i s t o these i s l a n d s t h a t we should t u r n i n looking f o r analogues of Cayman ecosystems, a s wel l a s t o i s l a n d s of s i m i l a r geology, topography and c l imate such a s t h e Swan I s l ands , Anegada and Barbuda. Atoll Research Bulletin No. 241: 171-180, 1980. E x t i n c t sgec i e s L i t t l e Cayman has t h e d i s t i n c t i o n o f being one o f t h e l e a s t s e t t l e d and hence l e a s t d i s tu rbed of a l l t he i s l a n d s of t h e Caribbean. I t owes t h i s d i s t i n c t i o n t o i t s rugged topography on d i s s e c t e d l imestone; i t s low and e r r a t i c r a i n f a l l , i t s b rack i sh w a t e r t a b l e , and hence e r r a t i c water supply; i t s tangled and o f t e n impenetrable vege t a t i on , dominated by scrub woodland; and i t s a s ton i sh ing l e v e l o f i n f e s t a t i o n by t h e mosquito Aedes t a e n i o r h y n c h u s . Never the less , i n s p i t e o f i t s handful1 of i n h a b i t a n t s , and p a r t l y because o f i t s proximity t o Cayman Brac, t h e i s l a n d has n o t been wholly unaf fec ted by change i n post-Columbian t imes. This Expediti-on had f o r i t s main purpose t h e documentation of t h e p r e s e n t fauna and f l o r a o f t h e i s l a n d : t h e r e a r e , however, important components o f t he b i o t a a l r eady now e x t i n c t . Both ground and a rbo rea l r e p t i l e s form a conspicuous element i n t h e fauna o f L i t t l e Cayman, wi th two gekkoes (one n o t seen i n 1975) , f ou r s p e c i e s 04 iguan id , one anguid, and two sn&es lone a l s o n o t seen i n 1975) . The c rocod i l e i s probably now e x t i n c t , however, and marine tur-Lles probchly hard ly ever now breed on L i t t l e Cayman shores . In 1642 W i l l i a m Jackson mentioned "ye mu l t i t ude o f A l l i g a t o r s " i n t h e Caymans a s a whole ( ~ a c k s o n 1924, 2 1 ) , and e a r l y Spanish c h a r t s named the i s l a n d s 'Lagar tos ' ( a l l i g a t o r s ) , a name, however, which Grant (1940, 5 ) t h i n k s r e f e r r e d t o C y c l u r a r a t h e r than t o c rocod i l e s . The f i r s t s c i e n t i f i c r e p o r t of c rocod i l e s i s t h a t by C . J . Maynard i n Garman's (1888, 108) paper on t h e fo rmer ' s c o l l e c t i o n s . Maynard s t a t e s t h a t "Two spec i e s of c rocod i l e have been taken on t h i s i s l a n d and one on Cayman Brac. I saw b u t a p o r t i o n o f one specimen. The n a t i v e s a s su red me t h a t t he s p e c i e s were s i m i l a r t o those found i n Cuba". Chapman Grant c o l l e c t e d on L i t t l e Cayman i n Apr i l 1938, a s d i d C. Bernard Lewis i n May-June t h e same year . They ev iden t ly d i d n o t s ee t h e c rocod i l e , b u t Grant (1940, 14) records t h a t "On October 27, 1939, Captain James Banks o f L i t t l e Cayman s e n t t h e w r i t e r t h e head and f e e t of a c rocod i l e which he took on t h a t i s l a n d . The head measures 310 rnm i n l eng th . The d e n t i t i o n agrees wi th t h e Jamaican specimens of a c u t u s i n t h e a u t h o r ' s c o l l e c t i o n . The c rocod i l e was about seven f e e t long and was one o f two which Captain Banks came upon near Charles Bay - about half-way along t h e south c o a s t of L i t t l e Cayman". There i s no subsequent r eco rd of l i v i n g c rocod i l e s on t h e i s l a n d , and it i s h igh ly u n l i k e l y t h a t t h e spec i e s s t i l l e x i s t s t h e r e . There i s no means now of knowing wi th c e r t a i n t y whether t h e r e was a l a r g e and r e s i d e n t l o c a l popula t ion , o r whether occas iona l i n d i v i d u a l s d r i f t e d t o t h e i s l a n d from Jamaica o r Cuba; it i s p o s s i b l e t h a t r e c o l o n i s a t i o n might occur from these i s l a n d s . Marine t u r t l e s have been equa l ly e x t i r p a t e d l o c a l l y . T u r t l i n g apparen t ly began on a cons iderab le s c a l e i n t h e Caymans i n t h e second h a l f of t h e seventeenth cen tury (Dampier 1729, 3 0 ) , a l though Columbus i n 1503 had found t h e i s l a n d s t o be " f u l l o f t o r t o i s e s , a s was a l l t h e s e a about". Hans Sloane passed through t h e Lesser Caymans i n March 1688, when Cayman Brac a l ready had "some Huts f o r t he T u r t l e r s " , though by t h a t time t h e t u r t l e s t he re "were b u t few" (Sloane1725, 342). He descr ibed 40 sloops from P o r t Royal, Jamaica, a s c o n s t i t u t i n g the t u r t l i n g f l e e t , with a four-man sloop br inging i n 30-50 t u r t l e s which i n good condi t ions might be c o l l e c t e d i n a s i n g l e day (Sloane 1707, x v i i , l x x x v i i i ) . I t was be l ieved t h a t t h e t u r t l e s migrated from the Gulf of Honduras and t h e Nicaraguan Banks t o breed i n the Caymans and along t h e south coas t of Cuba during May-September. Long (1774, 309- 313) g ives a d e t a i l e d account of the n a t u r a l h i s t o r y of t h e t u r t l e and of t he Cayman t u r t l e t r ade . By t h e e a r l y n ine teenth century, however, Caymanian t u r t l e r s were obta in ing a l l t h e i r t u r t l e s on t h e Mosquito Keys and t h e coas t of Nicaragua (Young 1842, 17-18), a s well a s o f f Cuba. A l l of t h i s information r e l a t e s t o the Green T u r t l e C h e l o n i a mydas , Undoubtedly i t s main nes t ing grounds were i n West Bay, Grand Cayman, wi th subs id iary populat ions on tile more r e s t r i c t e d beaches elsewhere. On L i t t l e Cayman the main nes t ing a reas w r e probably a t Sandy Poin t and on the narrow b u t long beaches of the nor th and south coas t s . Lewis (1940, 62-64) a l s o r e f e r r e d t o t h e Loggerhead C a r e t t a c a r e t t a a s "s t i l l common" and breeding on a l l t h r e e i s l a n d s i n June; the Hawksbill Bretrnochelys i m b r i c a t a a s " f a i r l y comon" though r a r e l y lay ing; and the Leatherback Dermochelys c o r i a c e a a s " r a r e l y seen" b u t occas ional ly breeding. Breeding of any spec ie s of t u r t l e i n t h e Cayman I s l ands i s probably now a r a t h e r unusual event , though perhaps l e a s t s o on L i t t l e Cayman. A s popula t ions , however, t he Cayman t u r t l e s now no longer e x i s t . We have no information on the p resen t s t a t u s of the gecko A r i s t e l l i g e r p r a e s i g n i s and the snake T r o p i d o p h i s c a ymanens is p a r k e r i , previous ly recorded b u t not found by Hounsome i n 1975. Mammals No n a t i v e mammals have been recorded from L i t t l e Cayman. I n 1965, however, Pat ton (1966) discovered remains of the i n s e c t i v o r e Nesophon te s and therodentGeocapromys on Cayman Brac. Both genera a r e r ep resen ta t ives of a d i s t i n c t i v e n a t i v e Greater An t i l l ean mammal fauna. Nesophon te s is represented by f o s s i l remains on Cuba, Hispaniola and Puerto Rico. Geocapromys, t h e s h o r t - t a i l e d h u t i a , i s represented by f o s s i l and l i v i n g spec ie s i n Cuba, Jamaica, t he Bahamas, and L i t t l e Swan I s l a n d (where it has r e c e n t l y been repor ted t o have become e x t i n c t : Clough 1976). In a d d i t i o n , Darlington (1965, 391) records a f o s s i l long- ta i led h u t i a Capromys from t h e Cayman I s l ands ; t h i s genus i s represented by l i v i n g spec ies i n Cuba and the I s l e of Pines. Though not so f a r recorded on L i t t l e Cayman, it would be s u r p r i s i n g i f t he s tudy of cave depos i t s d i d no t l ead t o t h e discovery of f o s s i l v e r t e b r a t e s on the i s l a n d . So f a r nothing i s known of t h e i r age on Cayman Brac, o r of t h e reasons f o r t h e i r exterminat ion, b u t a t l e a s t on L i t t l e Swan Geocapromys survived u n t i l ca 1950. Species a t r i s k Although conserva t ion o f spec i e s i s b e s t considered i n terms o f conserva t ion o f h a b i t a t s , it i s neve r the l e s s u s e f u l t o cons ider which t a x a might be a t r i s k i f development o f L i t t l e Cayman t akes p lace . Molluscs Hounsome and Askew ( t h i s volume) have f u l l y documented t h e r a r i t y of t h e L i t t l e Cayman pulmonate C e r i o n n a n u s . I t i s c l e a r t h a t t h i s spec i e s would immediately become e x t i n c t i f i t s h a b i t a t of E v o l v u l u s scrub were t o be c l e a r e d , and s ince t h e main a r e a o f t h i s sc rub l i e s on t h e t r a n s - i s l a n d t r a c k from Blossom Vi l l age , c l o s e t o p o s s i b l e development s i t e s , t h i s seems h igh ly l i k e l y t o occur . I t i s more d i f f i c u l t t o e s t i m a t e t h e s e r iousnes s of such an e x t i n c t i o n , e s p e c i a l l y i n s o widespread and v a r i a b l e a genus a s C e r i o n , which, moreover, S . J . Gould and h i s c o l l a b o r a t o r s a r e c u r r e n t l y s u b j e c t i n g to major r ev i s ion . R e p t i l e s The l a r g e iguanid o f t he genus C y c l u r a i s of p a r t i c u l a r i n t e r e s t i n t h e Cayman I s l a n d s . This genus i s widespread i n t h e Grea te r A n t i l l e s : i n Cuba, t h e I s l e of P ines , Hispanio la , Jamaica, Puer to Rico, Navassa, t h e Bahamas, Anegada, and t h e Turks and Caicos I s l a n d s , though over some o f t h i s range it i s represen ted only by f o s s i l o r r e c e n t l y e x t i n c t spec i e s (Schwartz and Thomas 1965) . Ecologica l ly , i t may be compared wi th t h e Cent ra l American genera C t e n o s a u r a (which reaches o u t i n t o t h e Caribbean a t Half Moon Cay, Lighthouse Reef, Be l i ze ) and I g u a n a (found on Swan I s l a n d ) , and t o a l e s s e r degree wi th A m b l y r h y n c h u s and C o n o l o p h u s i n t h e ~ a l 6 ~ a g o s I s l ands . The spec i e s on L i t t l e Cayman ( C y c l u r a n u b i l a c a y m a n e n s i s Barbour and Noble) i s a l s o n a t i v e on Cayman Brac, and has been introduced t o Grand Cayman, where t h e r e is another n a t i v e subspec ies , C . n . l e w i s i Grant . Grant (1940, 29-37) descr ibed the Cayman I s l a n d s C y c l u r a i n d e t a i l , inc lud ing e c o l o g i c a l no tes by C , B . Lewis. The l i z a r d s a r e herb ivorous , and on L i t t l e Cayman feed on I p o m o e a p e s - c a p r a e , E r n o d e a l i t t o r a l i s and C o r d i a s e b e s t e n a . Lewis noted t h a t they were on ly seen wi th in 100 ya rds of t h e shore. Carey (1966) has s tud i ed C . n . c a y m a n e n s i s on Cayman Brac, where i n 1965 it was confined t o a small a r e a on t h e southwest s i d e of t h e i s l a n d . Lewis (1944, 95) considered t h a t t h e co lon ie s o f C y c l u r a on both i s l a n d s " a r e reproducing, gene ra l l y f l o u r i s h i n g and a r e i n no danger o f ex t inc t ion" . However, he a l s o s t a t e d ( i n Grant 1940, 34) t h a t " t h e popula t ions a r e r a p i d l y being. reduced by dogs, which these l i z a r d s seem unable t o escape, a l though f i g h t i n g we l l and occas iona l ly i n j u r i n g t h e i r a t t a c k e r . There i s a l a r g e colony on t h e south shore o f L i t t l e Cayman a t mid-is land, which i s a t p r e s e n t s u f f i c i e n t l y i s o l a t e d t o escape pe r secu t ion by dogs and man". There i s no doubt t h a t C y c l u r a i s p a r t i c u l a r l y vu lnerab le t o p reda t ion by in t roduced mammals. I n Jamaica C y c l u r a co l le i i s now e x t i n c t , d e s p i t e e f f o r t s t o p re se rve it, a s a r e s u l t of t h e i n t roduc t ion o f mongoose i n 1872 (Lewis 1944) . C . c o r n u t a o n c h i o p s i s h a s a l s o become e x t i n c t on Navassa, and C . m a t t e a and C . p o r t o r i c e n s i s a r e known on ly from f o s s i l m a t e r i a l on S t Thomas, Vi rg in I s l a n d s , and i n Puer to Rico, r e s p e c t i v e l y . The r a p i d i t y wi th which e x t i n c t i o n can take p l a c e has been documented f o r Pine Cay, Turks and Caicos I s l a n d s , by Iverson (1978) , where i n t h e e a r l y 1970s t h e r e was a popula t ion of 5500 i n d i v i d u a l s of C . c a r i n a t a . A h o t e l was b u i l t on t h e i s l a n d i n 1973, and domestic c a t s and dogs in t roduced . These preyed on t h e l i z a r d s , which had become e x t i n c t by 1978. Iverson comments (1978, 63) t h a t t h e s e rock iguanas a r e "among t h e most r a p i d l y d e c l i n i n g of t h e wor ld ' s r e p t i l e spec i e s " . C . n u b i l a caymanens i s i s on ly commonly seen on L i t t l e Cayman i n t h e v i c i n i t y of South Hole Sound. The former i s o l a t i o n o f t h i s a r e a has disappeared wi th t h e c o n s t r u c t i o n of t h e circwn-is land road and t h e a i r f i e l d . I t would seem almost i n e v i t a b l e t h a t dogs and c a t s would be in t roduced i n consequence of any i n d u s t r i a l o r t o u r i s t development, and even i f they were c o n t r o l l e d t h e a r e a s i n which t h e l i z a r d s a r e found would be a t g r e a t r i s k from d i r e c t h a b i t a t modi f ica t ion . There i s an u rgen t need f o r a f u l l i n v e s t i g a t i o n of t h i s s p e c i e s on L i t t l e Cayman, s i n c e a t p r e s e n t ou r information i s inadequate f o r t h e formulat ion of a conserva t ion p o l i c y f o r it. Indeed, c y c l u r i d l i z a r d s a r e only w e l l known i n t h e s i m i l a r h a b i t a t of Anegada, where C . p i n g u i s has been s tud i ed by Carey (1975) . On s c i e n t i f i c grounds, t oo , it would be of g r e a t i n t e r e s t t o compare C y c l u r a with t h e mainland iguanid Ctenosaura s i m i l i s , r e c e n t l y s tud i ed i n Bel ize and Nicaragua (Henderson 1973, F i t c h and Henderson 1978) . B i rds A s Diamond ( t h i s volume) has shown, t h e land b i r d s a r e g e n e r a l l y numerous and n o t immediately a t r i s k , except a s a r e s u l t of massive h a b i t a t change; t h i s appears u n l i k e l y t o occur except on a ve ry l o c a l s c a l e . The seab i rds a r e , however, more vu lne rab l e . Th i s i s p a r t i c u l a r l y t r u e of t h e colony o f Red-footed Booby on t h e nor thern margins of t h e Blossom Vi l l age sal t -pond. While t h i s i s now knobm t o c o n s i s t of t h e p a n t r o p i c a l s p e c i e s S u l a s u l a , r a t h e r than t h e o r i g i n a l l y descr ibed endemic S . c o r y i , it i s neve r the l e s s of cons iderab le importance i n Caribbean terms, and may indeed be t h e l a r g e s t colony of t h i s s p e c i e s i n t h e a r e a . Diamond e s t i m a t e s t h a t it inc ludes a t l e a s t 7100 b i r d s . The only comparable c o l o n i e s appear t o be t hose on Half Moon Cay, Lighthouse Reef, Be l i ze , where Verner (1961) e s t ima ted a popula t ion o f 3500, excluding n e s t l i n g s , and on L i t t l e Swan I s l a n d . There i s no e s t i m a t e of t h e s i z e of t h e l a t t e r popula t ion , though it has been descr ibed a s l a r g e by Lowe (19091, F i she r and Wetmore (1931) , and S tewar t (1960); t h e r e i s no subsequent information on i t s s t a t u s . The number of Magnificent F r i g a t e b i r d s Frega ta m a g n i f i c e n s i n t h e same colony on L i t t l e Cayman i s much sma l l e r , and t h e r e a r e much l a r g e r co lon ie s on Barbuda (2500 p a i r s : Biamond 1973) , t h e n o r t h c o a s t of Yucatan (2500 n e s t s , quoted by Diamond 19731, and on L i t t l e Swan I s l a n d , where, however, t h e r e i s no r e c e n t information on t h e s i z e of t he colony. Habi ta t s a t r i s k As Diamond ( t h i s volume) has succ inc t ly s t a t e d : " I t i s i n the almost completely undisturbed na ture of t he i s l a n d a s a whole t h a t i t s ch ief b i o l o g i c a l i n t e r e s t l i e s " . I t follows t h a t the arguments f o r conservat ion l i e l e s s i n concern f o r p a r t i c u l a r i nd iv idua l spec ies than f o r undisturbed h a b i t a t s . The i n t e r e s t of L i t t l e Cayman l i e s i n i t s rugged and d i f f i c u l t t e r r a i n ; i t s undisturbed scrub, scrub woodland, and woodland; i t s r e p t i l e fauna dominated by the ground iguana C y c l u r a and abundant a rborea l l i z a r d s ; i t s enormous decapod crustacean popula t ions , e s p e c i a l l y of Cardisoma guanhumi; i t s 600 spec ies of i n s e c t s ; i t s land-bi rds ; and i t s s eab i rds , a l l co-exist ing under condi t ions l i t t l e a f f e c t e d by man. The main hzibitats of conservdtion ~ n t c r c s t a r e cis fc?ll.ows (Figure 3 4 ) , I n t e r i o r woodl23-d The a rea of t a l l Dry Evergreen Fores t i n the i n t e r i o r of the i s l a n d i s , eco log ica l ly , one of t h e most remarkable h a b i t a t s of L i t t l e Cayman. On most o t h e r smaller Caribbean i s l a n d s ( e .9 . Barbuda) such woodland has long s ince disappeared, b u t on L i t t l e Cayman it remains extremely i s o l a t e d and v i r t u a l l y undisturbed. I ts preserva t ion i s thus of f a r more than l o c a l s ign i f i cance : it i s of Caribbean-wide importance. This i s so i n s p i t e of t h e f a c t t h a t it i s no t obviously a s soc ia t ed wi th spec tacu la r , r a r e o r threatened spec ies , though Hounsome ( t h i s volume) co l l ec t ed some 16 spec ies of t e r r e s t r i a l animals ( o t h e r than i n s e c t s ) only i n t h i s h a b i t a t . Manarove woodland Two a reas of mangrove woodland r equ i re conservat ion. One i s t h a t on the nor th shore of t h e Blossom Vi l lage salt-pond, used by t h e nes t ing boobies. This i s no t only suscep t ib l e t o clearance, b u t a l s o t o d is turbance by repeated v i s i t i n g , and by overf ly ing from the ad jacent a i r f i e l d . Diamond has shown t h a t t he booby colony i s one of t he l a r g e s t i n the Caribbean, and i t s conservation i s thus of reg ional importance. The second a rea i s t he t a l l mangrove woodland around Tarpon Lake. This i s of l o c a l importance a s a r ep resen ta t ive of t h i s type of h a b i t a t on L i t t l e Cayman, though of course widespread i n o t h e r p a r t s of t he Caribbean, including Grand Cayman; it a l s o has some amenity p o t e n t i a l . Inland a reas of dwarf R h i z o p h o r a a r e a l s o e c o l o g i c a l l y i n t e r e s t i n g , and l e s s widespread i n t h e Caribbean than o t h e r types of mangrove h a b i t a t . E v o l v u l u s heath The importance of t h i s h a b i t a t has already been d iscussed i n t h e context of t he p rese rva t ion of the land s n a i l C e r i o n n a n u s . S e s u v i u m marsh The in l and monospecific herbaceous marsh dominated by S e s u v i u m p o r t u l a c a s t r u m a t t h e e a s t end of L i t t l e Cayman r e p r e s e n t s a very unusual h a b i t a t . I t i s important f o r i t s i n s e c t popula t ions , e s p e c i a l l y of d r a g o n f l i e s , and poss ib ly a l s o f o r t h e t r e e duck D e n d r o c y g n a a r b o r e a . I t i s d i f f i c u l t t o imagine so remote an a r e a be ing d i r e c t l y d i s tu rbed , however. Coas ta l f l a t s These a r e a s have a l r eady been g r e a t l y d i s tu rbed , e s p e c i a l l y by t h e gene ra l p l a n t i n g of coconuts a t t h e end of t he n ine t een th cen tury , by o t h e r c u l ~ i v a t i o n and c l e a r i n g , and by se t t l emen t , This has had the r e s u l t of replac]-ng what was probably a r a t h e r uniform s t r and woodland by new types o f waodlann, s c rub , and open herbaceous h a b i r h t s . Askew ( t h l s volume) has noted t h e d1versit.y of l n s e c t s i n t he se c o a s t a l a r e a s . Now t h a t access by road i s p o s s l b l e along almost t h e e n t l r e c o a s t , i c has become more important t o preserve t he surv iv ing remnants of n a t l v e c o a s t a l woodland, and t o a t tempt t o con t ro l t he a c t i v i t i e s of introduced anlmals. Ra ts a r e now ubiqui tous i n t h e c o a s t a l a r e a s , b u t c a t s and dogs appear s t i l l t o be conflned t o t h e s e t t l emen t s . The prevent ion of e ros ion dur ing storms i s a l s o c r i t i c a l l y dependent on t h e p r e s e r v a t i o n , wherever p o s s i b l e , of beach-crest sc rub and sc rub woodland. Marine h a b i t a t s During the 1975 Expedi t ion marine s t u d i e s were concent ra ted on t h e h a b i t a t s of South Hole Sound, i n view of i t s t o u r i s t p o t e n t i a l and a l s o s u s c e p t i b i l i t y t o change i n t h e event of expanding se t t l emen t a t Blossom Vi l l age , and on t h e l i t t o r a l fauna and f l o r a round the whole i s l a n d ( P o t t s , t h i s volume), I t i s l i k e l y t h a t r e e f - f l a t and r e e f faunas and f l o r a s a r e c l o s e l y comparable with t hose more i n t e n s i v e l y i n v e s t i g a t e d on Grand Cayman (Rigby and Roberts 1976, Raymont, Lockwood, Hull and Swain 1976a, 1976b). There i s no reason t o suppose t h a t Cayman marine h a b i t a t s d i f f e r i n any fundamental way from those c h a r a c t e r i s t i c o f Caribbean c o r a l r e e f s i n genera l (S toddar t 1977) , b u t it i s c e r t a i n l y t r u e t h a t , e s p e c i a l l y i n t h e Lesser Caymans, d i s turbance by man has been minimal, i n c o n t r a s t t o many o t h e r Caribbean l o c a l i t i e s . A s a r e s u l t , r ee f f i s h faunas have n o t been d i s rup t ed by s p e a r f i s h i n g and a r e thus of cons iderab le s c i e n t i f i c i n t e r e s t ( P o t t s , i n p r e p a r a t i o n ) . Two main marine a r e a s have been recommended by P o t t s (1975) a s marine r e se rves (F igure 3 4 ) . They a r e : ( a ) The e a s t e r n , windward end of t h e i s l a n d , wi th well-developed c o r a l r e e f s , remote from any se t t l ement . ( b ) The a r e a on t h e n o r t h e a s t c o a s t from S a l t Rocks t o Jackson ' s Poin t . This second a r e a i nc ludes t h e i n t e r e s t i n g i n t e r t i d ' a l and s u p r a t i d a l exposure o f I ronshore a t S a l t Rocks, and t h e soyca l l ed 'Cayman W a l l ' , a s t eep reef-edge drop-off i n Bloody Bay, which plunges v e r t i c a l l y from 10 t o 200 m. This l a t t e r i s already well-known t o d ive r s . C o n f l i c t between conservat ion requirements and development proposa ls would appear, however, t o be i n e v i t a b l e i n t h e marine sphere. Proposals now being implemented c a l l fo r tanker trans-shipment f a c i l i t i e s , with shore i n s t a l l a t i o n s , a t S a l t Rocks, and f o r docking f a c i l i t i e s along the Bloody Bay drop-off. There remains t h e p o s s i b i l i t y of e s t a b l i s h i n g a marine r e se rve a t t he e a s t e r n end, and a l s o of emphasising the need f o r f u r t h e r s t u d i e s i n t h e r ee f a reas l i k e l y t o be d i r e c t l y a f f e c t e d by development. Conclusion A s s o o f t e n , t h e s c i e n t i f i c i n t e r e s t and importance of an i s l a n d only becomes recognized when Large-scale development i s planned. Although t h e Oxford Universi ty Expedition of 1938 suppl ied the groundwo~li of our knowledge of t he fauna and f l o r a of L i t t l e Cayman, it was not u n t i l 1975 t h a t an attempt was made t o d i s t i n g u i s h marine and t e r r e s t r i a l h a b i t a t s which might be a t r i s k i n the event of development. We a r e now i n a pos i t i on t o apprec ia te with g r e a t e r p r e c i s i o n than before the impact of i n d u s t r i a l i s a t i o n on such an i s l a n d , and we have been ab le t o de f ine a reas of s c i e n t i f i c importance which should be conserved during any such development. A t t he same t ime, we should emphasise t h a t t h i s r e p o r t i s based on only one month's i n v e s t i g a t i o n , and note t h a t not only i s t he re a g r e a t d e a l of f u r t h e r work t o be done b u t t h a t such s tud ie s should form an i n t e g r a l p a r t of any scheme f o r t h e f u t u r e of the i s l a n d . The n a t u r a l h a b i t a t s of L i t t l e Cayman a r e of s u f f i c i e n t importance t o be considered i n a Caribbean r a t h e r than simply a Caymanian context , s ince few s i m i l a r undisturbed environments s t i l l survive elsewhere, and it would be shor t -s ighted i n the extreme t o damage a h e r i t a g e and resource of t h i s charac ter f o r immediate economic advantage without t he f u l l e s t cons idera t ion of t he i r r e v e r s i b l e consequences of development and of t he a l t e r n a t i v e s t r a t e g i e s which may s t i l l be open fo r t h e f u t u r e . References Carey, W . M . 1975. 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N a r r a t i v e o f a r e s i d e n c e on the Mosqu i to S h o r e , d u r i n g the y e a r s 1 8 3 9 , 1840 and 1841 . London. Smith, E lde r and Co. i v , 172 pp. Sal Rock Marine conservation area Terrestrial conservation area 0:::: Mangrove and lagoon Figure 34. Recommended marine and t e r r e s t r i a l conservation areas , L i t t l e Cayman