NO. 241 March 1980
ATOLL RESEARCH BULLETIN
241. Geography and Ecology
ofLittle
CaymanEdiled by D.R. Sroddm
andM.E.C. GiglioLi
Issued by
THE SMITHSONIAN INSTlTUTION
Washington, D.C., U.S.A.
Issued
byTHE SMIrI'NS0NIAN INS'I'ITUI'ION ashington.
L3.C..U.S.A.
March 1980
ACKNOWLEDGEMENT
The A t o l l R e s e a r c h B u l l e t i n i s i s s u e d by t h e S m i t h s o n i a n I n s t i t u t i o n , a s a p a r t o f i t s a c t i v i t y i n t r o p i c a l b i o l o g y , t o p l a c e on r e c o r d i n f o r m a t i o n on t h e b i o t a o f t r o p i c a l i s l a n d s a n d r e e f s , and o n t h e e n v i r o n m e n t t h a t s u p p o r t s t h e b i o t a . The B u l l e t i n i s s u p p o r t e d by t h e N a t i o n a l Museum o f N a t u r a l H i s t o r y a n d i s p r o d u c e d and d i s t r i b u t e d by t h e S m i t h s o n i a n P r e s s . The e d i t i n g i s d o n e by members o f t h e Museum s t a f f a n d by D r . D. R. S t o d d a r t ,
The B u l l e t i n was f o u n d e d a n d t h e f i r s t 1 1 7 numbers i s s u e d by t h e P a c i f i c S c i e n c e B o a r d , N a t i o n a l Academy o f S c i e n c e s , w i t h f i n a n c i a l s u p p o r t from t h e O f f i c e o f Naval R e s e a r c h . I t s p a g e s w e r e l a r g e l y d e v o t e d t o r e p o r t s r e s u l t i n g f r o m t h e P a c i f i c S c i e n c e B o a r d ' s C o r a l A t o l l Program,
The s o l e r e s p o n s i b i l i t y f o r a l l s t a t e m e n t s made by a u t h o r s o f p a p e r s i n t h e A t o l l R e s e a r c h B u l l e t i n r e s t s w i t h them, and s t a t e m e n t s made i n t h e B u l l e t i n d o n o t n e c e s s a r i l y r e p r e s e n t t h e v i e w s o f t h e
S m i t h s o n i a n n o r t h o s e o f t h e e d i t o r s o f t h e B u l l e t i n .
IT, R, h ' o s b e r g I a n G , M a c I n t y r e Me-Ti. S a c h e t
S m i t h s o n i a n i n s tiru t i o n V a s h i n g t o n ,
D.
C. 2G560D. R, S t o d d a r t
D e p a r t m e n t o f Geography U n i v e r s i t y o f Cambridge Downing P l a c e
Cambridge, England
ATOLL RESEARCH BULLETIN
No. 241
OELOCY OF LIT
@:clltd 1n
D.R.
3 t o t l r i a n t anti 11.E.(:. d;ielioliP l a t e 1. The s o u t h c o a s t o f L i t t l e Cayman, - from t h e s o u t h e a s t ; noon cumulus e x t e n d i n g a l o n g t h e l e n g t h of t h e i s l a n d
CONTRIBUTORS
R . R . ASKEW
Department o f Zoology, The U n i v e r s i t y , Manchester, England
A.W. DIAMOND
Department of Zoology, U n i v e r s i t y of N a i r o b i , N a i r o b i , Kenya
M. E. C . G I G L I O L I
Mosquito R e s e a r c h and C o n t r o l U n i t , Grand Cayman, Cayman I s l a n d s , West I n d i e s
M.V. HOUNSOME
The Manchester Museum, Manchester, England G.W, POTTS
Marine B i o l o g i c a l A s s o c i a t i o n of t h e U . K . , The Marine L a b o r a t o r y , Plymouth, England G . R . PROCTOR
N a t u r a l H i s t o r y D i v i s i o n , I n s t i t u t e o f J a m a i c a , K i n g s t o n , Jamaica
D . R . STODDART
Department of Geography, U n i v e r s i t y of Cambridge, Cambridge, England
C . WOODROFFE
Department of Geography, U n i v e r s i t y of S h e f f i e l d , S h e f f i e l d , England
iii
CONTENTS
S c i e n t i f i c survey of L i t t l e C a y m a n D.R. S t o d d a r t
G e o l o g y and g e o m o r p h o l o g y of L i t t l e C a y m a n D . R . S t o d d a r t
M a n g r o v e s e d i m e n t s of L i t t l e C a y m a n C . Woodroffe
T h e z o n a t i o n of rocky l i t t o r a l a r e a s around L i t - t l e C a y m a n
T h e l i t t o r a l f i s h e s of L i t t l e C a y m a n G. W . P o t t s
V e g e t a t i o n of L i t t l e C a y m a n D
.
R.
Stoddar tC h e c k l i s t of t h e p l a n t s of L i t t l e C a y m a n G . R . P r o c t o r
'l'errestrial f a u n a [ e x c l u d i ~ l q b i r d s and i n s e c t s ) or' L i t t l e C a ynan
C e r i o n I r m a ( M a y n a r d ) (Molluscs: C e r i o ~ l i d a e 1 or?
L i t t l e C a y m a n
M.V. H o u n s o m e a n d R . R . A s k e w T h e i n s e c t fauna of L i t t l e C a y m a n
R . R . A s k e w
T h e O d o n a t a of t h e C a y m a n I s l a n d s R . R . A s k e w
T h e b u t t e r f l y ( L e p i d o p t e r a , R h o p a l o c e r a ) fauna of t h e C a y m a n I s l a n d s
Page 1
11
1 7
2 3
4 3
5 3
7 1
8 1
9 1
9 7
115
R . R . A s k e w
13. Hawkmoths (Lepidoptera, Sphingidae) of L i t t l e Cayman 139 R. R
.
Askew14. Ecology and s p e c i e s turnover of t h e b i r d s of L i t t l e
Cayman 141
A.W. Diamond
15. The Red-footed Booby colony on L i t t l e Cayman: s i z e ,
s t r u c t u r e and s i g n i f i c a n c e 165
A.W. Diamond
16. L i t t l e Cayman: ecology and s i g n i f i c a n c e D.R. S t o d d a r t
LIST OF PLATES
1. The s o u t h c o a s t o f L i t t l e Cayman, from the s o u t h e a s t ; noon cumulus e x t e n d i n g a l o n g t h e l e n g t h of t h e i s l a n d F r o n t i s p i e c e F o l l o w i n g page 1 6
2. Sparrowhawk H i l l from t h e n o r t h c o a s t beach r i d g e 3. Limestone r i d g e i n l a n d of t h e c o a s t a l s a l t pond a t
C h a r l e s B i g h t
4. Limestone r i d g e and c o a s t a l sand f l a t and s a l t pond a t Mary's Bay
5 . D i s s e c t e d s u r f a c e on t h e B l u f f Limestone (6032 1 7 6 3 ) ; che s i d a s of t h e frame a r e 50 cm l o n g
6 . D e t a i l of s u r f a c e d i s s e c t i o n on B l u f f Limestone 7 . Large d o l i n e i n Bluff Limestone (6028 1778)
8. Cave speleothems r e v e a l e d by r o o f c o l l a p s e (6003 1781) 9. Bluff c o a s t a t E a s t P o i n t
10. I r o n s h o r e p l a t f o r m west of C a l a b a s h Spot
11. D i p l o r i a c o l c m i s s i n c o a s t a l I r o n s h o r e a - t S a l t Rocks I%, S t r o m b u s s h e i l s I n c o a s ~ a l I r o n s h o r e a t S a l t Rocks
13. I r o n s h o r e d e p o s i L s on t h e landward margins of t h e Blossom V i l l a g e lagoon
14. P o t h o l e s i n t h e I r o n s h o r e s u r f a c e a t S a l t Rocks
15. Bedded c a l c a r e n i t e s o v e r l y i n g r e e f f a c i e s i n t h e I r o n s h o r e a t S a l t Rocks
1 6 . D e t a i l of t h e bedded c a l c a r e n i t e s a t S a l t Rocks 1 7 . Beach r i d g e e a s t of P i r a t e ' s P o i n t
1 8 . Beach r i d g e a t Calabash P o i n t
1 9 . Sand beach r i d g e w i t h j u v e n i l e C a s u a r i n a i n Wearis Bay 2 0 . Storm wash-over c o b b l e s n o r t h of E a s t Rocky P o i n t , Blossom
Bay
2 1 . H u r r i c a n e - d e p o s i t e d storm b l o c k s on t h e I r o n s h o r e p l a t f o r m s o u t h of t h e a i r s t r i p (5957 1737)
F o l l o w i n g p a g e 42
P r e s t o n Bay showing t h e exposed l i t t o r a l r o c k s and s a n d y b e a c h above them
West End Rocks w i t h a l a r g e l i t t o r a l rock p o o l i n t h e f oreg.-ound
E c k i r l i n u s n o d i a l o s u s i n c r e v i c e s wi-th L i t t o r i n a z i c z a c on t h e upper m i d l i t t o r a l r e g i o n of Pres-ton Bay
T e c t a r i i a s r n u z - i c a t u s (arrowed) among t h e l e a v e s of , S e s u v i u m p o r t u l a c a s t r u m a . t West End Rocks
N e r i t a p e l o r o n t a and N. t e s s e l l a t a on r o c k s a t t h e m i d l i t t o r a l zone, E c b i n i n u s n o d u l o s u s and L i t t o r i n a z i c z a c a r e p r e s e n t i n c r e v i c e s
T u r b i n a r i a t u r b i n a t a , P a d i n a s a n c t a e - c r u c i s and D i c t y o t a s p . i n t h e lower m i d l i t t o r a l zone a t West End Rocks E a s t End showing t h e s t e e p and d e e p l y d i s s e c t e d l i t t o r a l r e g i o n
T e c t a r i u s r n u r i c a t u s i n l a r g e numbers i n -the s u p r a l i t t o r a l f r i n g e a t E a s t End
~ c a r ~ t h o p l e u r a i j r a n u l a t a i n shallow rock p o o l s i n t h e lower m i d l i t t o r a l zone
Rock p o o l a t West End Rocks showing P u p e r i t a pupa and L i t t o r i n a m e s p i l l u r n s c a t t e r e d over t h e bottom of t h e p o o l
v i i 35. P u p e r i t a pupa g a t h e r e d on a rocky p i n n a c l e w i t h i n a r o c k pool 36. Diadema a n t i l l a r u m i n a low t i d e l e v e l r o c k p o o l a t P r e s t o n
Bay
F o l l o w i n g p a g e 7 0
37. Dry e v e r g r e e n f o r e s t s o u t h of Sparrowhawk H i l l ; n o t e t h e human f i g u r e i n t h e c e n t r e of t h e p i c t u r e (6003 1775)
38. Dry e v e r g r e e n woodland i n l a n d from J a c k s o n ' s Bay (5977 1768) 39. Dry e v e r g r e e n t h i c k e t on Sparrowhawk H i l l (6004 1780)
40. Open d r y e v e r g r e e n t h i c k e t on t h e n o r t h e r n s l o p e s of Sparrowhawk H i l l (6003 1781)
41. A c r o s t i c h u m a u r e u m i n l i m e s t o n e s o l u t i o n h o l e s n o r t h of Blossom V i l l a g e (5953 1750)
42. Wind-sheared c o a s t a l hedge of C o c c o l o b a w i f e r a , Owen I s l a n d 4 P i o n e e r H y m e n o c a l l i s l i t o r e a and o t h e r h e r b a c e o c s p i o n e e r s
a t Sandy P o i n t
44. D e c a p i t a t e d c o c o n u t s on t h e c o a s t a l beach r i d g e n e a r West P o i n t
45. Coconut p l a n t a t i o n w i t h many dead t r e e s on Owen I s l a n d
46. Low R h i z o p h o r a i n t h e c o a s t a l lagoon e a s t of D i g g a r y ' s P o i n t (6030 1773)
47, T a l l A v i c e n n i a woodland i n Tarpon Lake 4 8 , ' i ' a i l l i i l i z o p h o r a ;.ioociland i n Tarpon Lake
49- I n t e r i o r of t a l l R i i i z o p h o r a woodland a t Tarpon Lake
50, Dwarf i n l a n d R h i z o p h o r a i n an i n t e r i o r d e p r e s s i o n (5975 17613 51. I n l a n d S e s u v i u ~ n marsh w i t h open p o o l s a t t h e e a s t end of t h e
i s l a n d (6074 1795) F o l l o w i n g p a g e 96
52. The s i t e on t h e t r a n s - i s l a n d t r a c k n o r t h of Blosson V i l l a g e where l i v i n g Cerion n a n u s was found. The s n a i l s were l i v i n g on s h r u b s of E v o l v u l u s a r b u s c u l a h e r e seen growing on t h e p a t h
v i i i
5 3 . C e r i o n n a n u s and young C.pannosum on a s i n g l e p l a n t of E v o l v u l u s a r b u s c u l a . I n s e t : a l i v i n g specimen of C . n a n u s 5 4 . S i x s h e l l s of C . n a n u s with an example of C . pannosum f o r
comparison ( t o t h e same s c a l e ) . Four t y p i c a l s h e l l s a r e shown t o g e t h e r w i t h two examples of extremes i n l e n g t h / h e i g h t r a t i o
L I S T OF FIGURES
F o l l o w i n g p a g e 10
1. L o c a t i o n of t h e Cayman I s l a n d s 2 . Iilonth1.y r a i n f a l l . a t L i t t l e Cayman F o l l o w i n g page 1 6
3. Topography of L i t t l e Cayman, b a s e d on t h e D i r e c t o r a t e of Overseas Surveys l : 2 5 , 0 0 0 map (1965)
4 . Topographic t r a v e r s e s A-F: f o r l o c a t i o n s s e e F i g u r e 3 5 . Geology and h a b i t a t s of L i t t l e Cayman
6. Topographic p r o f i l e s a t S a l t Rocks
7. Beach r i d g e and c l i f f e d c o a s t p r o f i l e s : f o r l o c a t i o n s s e e F i g u r e 3
8. S i z e composition of beach sediments F o l l o w i n g page 22
9 , Topographic p r o f i l e of i n l a n d dwarf R h i z o p h o r a s c r u b LO, Topographic p r o f 1 I . e ~ of A, F h i z o p h o r a woodland a t Tarpon
Lake, I3, North c o a s t s a l t - p o n d R h i z o p i l o z a woodland n e a r Sparrowhawk Hil. l
11, Map of L i t t l e Cayman showing t h e main c o a s t a l sampling a r e a s 1 2 . Graphs of t h e d a i l y t i d a l r a n g e d u r i n g t h e p e r i o d of t h e
e x p e d i t i o n t o g e t h e r w i t h h o u r l y t i d a l h e i g h t s on a neap t i d e and a s p r i n g t i d e . The d a t a were p r o v i d e d by D r . K. George and based on f i g u r e s o b t a i n e d from A d m i r a l t y T i d e T a b l e s , Vol. 11, 1975
P r o f i l e of t h e s h o r e a t P r e s t o n Bay w i t h an i n d i c a t i o n of t h e v e r t i c a l z o n a t i o n of t h e l i t t o r a l s p e c i e s . The i n s e t shows how on t h e upper s h o r e some s p e c i e s remain i n p o o l s ( N e r i t a
v e r s i c o l o r ) , i n m o i s t c r e v i c e s ( L i t t o r i n a z i c z a c ) , and on t h e open r o c k ( E c h i n i n u s n o d u l o s u s and N o d i l i t t o r i n a t u b e r c u l a t a ) . L i t t o r i n a z i c z a c r e f e r s t o t h e a p p r o p r i a t e s p e c i e s of t h e L. z i c z a c "complex" (Borkowski and Borkowski, 1969) found i n an a r e a , and d o e s s o i n s u b s e q u e n t f i g u r e s Histograms i n d i c a t i n g t h e d i s t r i b u t i o n of f o u r s p e c i e s of g a s t r o p o d a l o n g t h e j e t t y a t P r e s t o n Bay. Black columns r e p r e s e n t t h e e a s t s i d e of t h e j e t t y and s t i p p l e d columns t h e w e s t s i d e
P r o f i l e of t h e s h o r e a t West End Rocks w i t h an i n d i c a t i o n of t h e v e r t i c a l z o n a t i o n of t h e common l i t t o r a l s p e c i e s
P r o f i l e of t h e s h o r e a t J a c k s o n ' s Bay P o i n t i n d i c a t i n g t h e v e r t i c a l z o n a t i o n of t h e common l i t t o r a l s p e c i e s . The d o d i e o c c u r r e n c e of some l i t t o r i n i d s and n e r i t e s i s a r e s u l t of t h e i r p r e s e n c e on a l a r g e b o u l d e r found j u s t below MLWM The d i s t r i b u t i o n of r n o l l u s c a ~ ~ zones around. a bou.ld.er a t J a c k s o n ' s Bay P o i n t ( s e e F i g u r e 1 6 ) . I t s h o u l d b e n o t i c e d t h a t t h e r e i s a d i f f e r e n c e i n t h e e x t e n t of t h e zones on t h e seaward and landward s i d e s of t h e b o u l d e r
P r o f i l e of t h e s h o r e a t t h e E a s t End i n d i c a t i n g t h e d i s t r i b u t i o n of t h e common l i t t o r a l s p e c i e s
O u t l i n e s and o r i e n t a t i o n s of l i t t o r a l r o c k p o o l s a t West End Rocks and J a c k s o n ' s Bay. P o o l s A , B and C o c c u r r e d a t a p p r o x i m a t e l y m i d - t i d e l e v e l s and D , E and F a t low t i d e l e v e l s . A d i a g r a z m a c i c s e c c l o n X-Y of p o o l A i s g i v e n w i t h t h e d i s t r i b u ~ i o n of some of t h e common r o c k p o o l i n v e r t e b r a t e s
t70110winy page 52
20. Dlagran! of ( a ) S p l a s h Zone and. ( b ) S u y e Zone ; > O O ~ S w i t h t h e i r t y p l c a i inhabitants: 1, Eucinostoiilus a r q e n c e u s ; 2 . B a t h y g o b i u s s o p o r a t o r ; 3. H b u d e f d u f s a x a t i l i s ; 4 . L u t j a n u s a p o d u s ;
5 . Gerres c i n e r e u s ; 6 . Tomicodon f a s c i a t u s ; 7 . A d i o r y x
v e x i l l a r i u s ; 8 . E u p o m a c e n t r u s l e u c o s t i c t u s ; 9. P u p e r i t a pupa;
10. A c e t a b u l a r i a s a n c t a e - c r u c i s ; 11. T h a l a s s o m a b i f a s c i a t u m ; 1 2 . Diadema a n t i l l a r u m ; 13. C a n t h i q a s t e r r o s t r a t a ;
14. L i t t o r i n a m e s p i l l u r n ; 15. E c h i d n a c a t e n a t a F o l l o w i n g page 7 0
2 1 . H a b i t a t s and geology of L i t t l e Cayman 2 2 . V e g e t a t i o n and topography of Owen I s l a n d
F o l l o w i n g page 90
23. Number of s p e c i e s ( o t h e r t h a n i n s e c t s and b i r d s ) and sampling s i t e s , L i t t l e Cayman, 1975
F o l l o w i n g p a g e 11 4
24. The p r o g r e s s i o n of i n s e c t s p e c i e s r e c o r d e d on L i t t l e Cayman by d a t e s . F u l l c i r c l e s s i g n i f y d a t e s on which h a l f t h e f i n a l t o t a l of s p e c i e s i n e a c h group were found. The l i g h t t r a p was f i r s t o p e r a t e d on 1 4 J u l y , t h e Malaise t r a p on 16 J u l y , and t h e main c e n t r a l f o r e s t c o l l e c t i o n s were made on 28 J u l y F o l l o w i n g page 138
25. The r e l a t i o n s h i p between t h e numbers of b u t t e r f l y s p e c i e s and t h e a r e a s ( s q km on a l o g a r i t h m i c s c a l e ) of Cuba, Hispa.niola, P u e r t o R i c o , Jamaica, and t h e Cayman I s l a n d s
( r = 0 . 9 8 )
2 6 . Map of L i t t l e Cayman showing l o c a l i t i e s mentioned i n t h e t e x t and t h e s i t u a t i o n of t h e t r a n s e c t s
2 7 . A s s o c i a t i o n s between t h e b u t t e r f l y f a u n a s of t h e G r e a t e r A n t i l l e s b a s e d upon mean v a l u e s of C o l e ' s C o e f f i c i e n t of A s s o c i a t i o n . The s c a l e r e p r e s e n t s p o s i t i v e v a l u e s of C o l e ' s C o e f f i c i e n t
28. Numbers of b u t t e r f l i e s s i g h t e d a t h o u r l y i n t e r v a . 1 ~ ( l o c a l t i m e ) d u r i n g t r a n s e c t s on t h r e e days a t P i r a t e ' s P o i n t , L i t t l e Cayman. Shade t e m p e r a t u r e s a r e shown above. For e a c h hour t h e columns r e p r e s e n t (from l e f t t o r i g h t ) 1 6 , 1 7 and 20 J u l y
30, M a p showing l o c a t l . o n af th.e ma-is! h a b i t a t s on 1~it.t.l.e C'ai~mari, p l a c e names, and c u t p a t h s used a s t r a i l s e c t s
31. Feeding h e i g h t s of f o u r i n s e c t i v o r o u s p a s s e r i n e s on L i t t l e Cay~nan: ( a ) Caribbean E l a e n i a ; ( b ) B a n a n a q u i t ; ( c ) V i t e l l i n e Warbler; ( d ) Yellow Warbler. O r d i n a t e : h e i g h t i n i n t e r v a l s of 2 m ( G r = g r o u n d ) . A b s c i s s a : p e r c e n t a g e of f e e d i n g o b s e r v a t i o n s i n each h e i g h t c l a s s . White a r e a s ( r i g h t o f 0 % ) : f e e d s on f r u i t ( E l a e n i a , V i t e l l i n e W a r b l e r ) o r n e c t a r
( B a n a n a q u i t , Yellow Warbler)
.
Black a r e a s ( l e f t of 0 % ) :f e e d s on i n s e c t s . For sample s i z e s , s e e T a b l e 29
x i i
F o l l o w i n g page 1 7 0
32. O u t l i n e map o f L i t t l e Cayman, showing t h e l o c a t i o n o f t h e booby c o l o n y and d e t a i l of t h e colony a r e a . Numerals r e f e r t o p r e v i o u s s i t e s of t h e c o l o n y ( s e e t e x t ) . L e t t e r s
r e p r e s e n t s e c t i o n s of t h e p r e s e n t c o l o n y used i n t h e c e n s u s ( s e e T a b l e 3 0 ) . Arrows r e p r e s e n t main f l i g h t l i n e s
33. D i u r n a l v a r i a t i o n i n number of b o o b i e s p r e s e n t i n t h e sample a r e a of t h e colony
F o l l o w i n g page 1 8 0
34. Recommended marine and t e r r e s t r i a l c o n s e r v a t i o n a r e a s , L i t t l e Cayman
x i i i
LIST OF TABLES
R a i n f a l l r e c o r d s a t L i t t l e Cayman. Data by c o u r t e s t y of t h e Mosquito Research and C o n t r o l U n i t , Grand Cayman P u b l i c a t i o n s on i n s e c t s of L i t t l e Cayman a r i s i n g from t h e Oxford U n i v e r s i t y E x p e d i t i o n t o t h e Cayman I s l a n d s i n 1938
S i z e d i s t r i b u t i o n of t h e common l i t t o r a l Mollusca around L i t t l e Cayman
D i s t r i b u t i o n of l i t t o r a l Mollusca C l a s s i f i c a t i o n of l i t t o r a l f i s h e s
Mean s i z e , sample s i z e and h a b i t a t p r e f e r e n c e of t h e f i s h e s found occupying s i x l i t t o r a l rock p o o l s
T e r r e s t r i a l fauna of L i t t l e Cayman ( e x c l u d i n g b i r d s and i n s e c t s ) , J u l y and August 1975
S p e c i e s d i v e r s i t y i n e a c h of t h e h a b i t a t t y p e s
Numbers of l i v i n g a d u l t Cerion nanus and Cerion pannosum found on Evolvulus p l a n t s , and t h e numbers of empty
Page 2
5
32
3 6 4 5
4 6
8 4 87
s h e l l s of t h e two s p e c i e s p e r 0.25 s q m , a t s i t e s A and B 94 Numbers of Evolvulus p l a n t s w i t h and w i t h o u t Cerion of
e i t h e r s p e c i e s a t s i t e s A and B 94
Numisers sf Evolvulus p l a t s c a r r y i n g I.ive Cerion of one or b o t h s p e c i e s a t s i t e 8. The e x p e c t e d f i g u r e s assume
a randoul d i s t r i b u t i o n of e a c h s p e c i e s 9 0 Ordina~l d i s t r i b u t i o n of s p e c i e s of i n s e c t s f o - a d on L i t t l e
Cayman. N u h e r s of s p e c i e s f o r North Mmerica n o r t h of Mexico a r e from B o r r o r and DeLong (1966)
Within-family s i z e r a n g e s of L i t t l e Cayman and B r i t i s h i n s e c t s . Dimensions a r e body l e n g t h ( e x c l u d i n g a n t e n n a e and abdominal appendages) e x c e p t f o r Odonata, N e u r o p t e r a and L e p i d o p t e r a where wing expanse i s g i v e n , and
S c a r a b a e i d a e f o r which e l y t r a l l e n g t h i s shown
P e r c e n t a g e composition of sweep-net saniples from L i t t l e Cayman compared w i t h t h o s e r e p o r t e d by Janzen and Pond
(1975) from Michigan, U.S.A.
xiv
P e r c e n t a g e c o m p o s i t i o n o f M a l a i s e t r a p samples from L i t t l e Cayman, and from Surinam and Kansas (Matthews a n d Matthews
1971) 1 1 0
Comparison o f l i g h t t r a p c a t c h e s o f M a c r o l e p i d o p t e r a on L i t t l e Cayman a n d a t Woodchester P a r k , G l o u c e s t e r s h i r e ,
England. 111
Numbers o f s p e c i e s c a u g h t by d i f f e r e n t methods on L i t t l e Cayman. F i g u r e s i n p a r e n t h e s e s show t h e numbers of
s p e c i e s c a u g h t o n l y by t h e method i n d i c a t e d , and t h e p e r c e n t a g e s a r e o f t h e numbers o f s p e c i e s c a u g h t by e a c h method o u t o f t h e t o t a l number o f s p e c i e s found on t h e i s l a n d b e l o n g i n g t o t h e g r o u p
S p e c i e s of Odonata r e c o r d e d from t h e Cayman I s l a n d s by t h e 1938 Oxford U n i v e r s i t y E x p e d i t i o n and t h e 1975 Royal S o c i e t y and Cayman I s l a n d s Government E x p e d i t i o n
B u t t e r f l y s p e c i e s r e c o r d e d by t h e 1938 and 1975 E x p e d i t i o n s t o t h e Cayman I s l a n d s
M a t r i x showing t h e numbers o f s p e c i e s s h a r e d bstween Cuba, H i s p a n i o l a , P u e r t o R i c o , Jamaica and t h e Cayman I s l a n d s (upper r i g h t ) , v a l u e s f o r C o l e ' s c o e f f i c i e n t of a s s o c i a t i o n ( l o w e r l e f t ) , and t h e t o t a l number of
b u t t e r f l y s p e c i e s r e c o r d e d f o r e a c h i s l a n d 132 Numbers of b u t t e r f l i e s c o u n t e d p e r f i v e m i n u t e s i n e a c h
h a b i t a t zone on t h r e e t r a n s e c t s o f L i t t l e Cayman 135 The s p e c i e s o f l a n d - b i r d s b r e e d i n g i n t h e Cayman I s l a n d s ,
and t h e i r d i s t r i b u t i o n e l s e w h e r e 14 3
D i s t r i b u t i o n a l a f f i x i t i e s of t h e b r e e d i n g l a n d - - b i r d s of t h e Cayman 1sianc"is and L i t t l e Cayman, F i g u r e s i n b r a c k e t s show t h e nl-1;nber of C e n t r a l A ~ ~ r i c a n s p c c i e s
t h a t a r e r e s t r i c t e d t o o f f s i l o r e i s l a n d s - 144 The endemic forms o f Cay~iian i s l a n d s l a n d - b i r d s , and
t h e i s l a n d s on which t h e y b r e e d . P o p u l a - t i o n s p r o b a b l y
e x t i n c - t a r e b r a c k e t e d 145
D i s t r i b u t i o n of Cayman I s l a n d s endemic l a n d - b i r d s . F i g u r e s i n b r a c k e t s show t o t a l s b e f o r e r e c e n t e x t i n c t i o n s
E x t i n c t i o n s a n d c o l o n i s a t i o n s i n t h e Cayman I s l a n d s
a v i f auna 149
Breeding r e c o r d s o f L i t t l e Cayman b i r d s , 9 J u l y - 1 1 August
1 9 75 1 5 0
2 8 . Average number of b i r d s p e r hour r e c o r d e d i n f o u r h a b i t a t s on L i t t l e Cayman
2 9 . H a b i t a t s of b r e e d i n g b i r d s of L i t t l e Cayman 15 2 30. Feeding methods of f o u r i n s e c t i v o r o u s p a s s e r i n e s on
L i t t l e Cayman 154
31. Census of b o o b i e s a l o n g t h e s o u t h e r n edge of t h e c o l o n y ,
0800-1000, 1 August 1975 167
