ATOLL RESEARCH BULLETIN NO. 254
NATURAL HISTORY OF RAINE ISLAND, GREAT BARRIER REEF
b y D. R. Stoddart, P. E. Gibbs, and D. Hopley
Issued by
THE SMITHSONIAN INSTITUTION Washington, D. C., U.S.A.
July 1981
CONTENTS Introduction
General description
Geology and geomorphology Topography
Lithology Stratigraphy Sediments
Interpretation and subsequent observations Phosphate deposits
Water supply
Vegetation and flora Invertebrates
Marine Turtles Birds
D u c u l a s p i l o r r h o a s p i l o r r h o a R a l l u s p h i l i p p e n s i s y o r k i
~ a l l i n u l a p o r p h y r i o m e l a n o t u s P u f f i n u s p a c i f i c u s
P t e r o d r o m a a r m i n j o n i a n a h e r a l d i c a F r e g a t a m i n o r
F r e g a t a a r i el
S u l a l e u c o g a s t e r p l o t u s S u l a s u l a r u b r i p e s
S u l a d a c t y l a t r a p e r s o n a t a P e l e c a n u s c o n s p i
ci
11 a t u s P h a e t hon r u b r i c a u d a S t e r n a b e r g i iS t e r n a f u s c a t a n u b i l o s a S t e r n a a n a e t h e t u s a n a e t h e t u s A n o u s s t o l i d u s p i l e a t u s A n o u s m i n u t u s m i n u t u s
L a r u s n o v a e h o l l a n d i a e
forsteri
A r e n a r i a i n t e r p r e s i n t e r p r e s P l u v i a l i s s q u a t a r o l aP l u v i a l i s d o m i n i c a f u l v a Numenius p h a e o p u s v a r i e g a t u s L i m o s a 1 a p p o n i c a b a u e r i C a l i d r i s r u f i c o l l i s C a l i d r i s a c u m i n a t a E g r e t t a a l b a m o d e s t a E g r e t t a s a c r a
Nycticorax caledonicus hilli Merops orna t us
Hi rundo ni gri cans ni gri cans Myiagra rubecula rubecula Aplonis metallica metallica Disturbance by Man
Construction of the Beacon Wreck of the Enchantress Beche-de-mer Fishery Phosphate mining Acknowledgements References
List of Figures
The northern Great Barrier Reef, showing the location of Raine Island.
Raine Island and its reef.
Monthly distribution of rainfall at Willis Island, 1921-1971 (data from Taylor 1973).
Raine Island in 1844, from Jukes (1847), vol. I, p. 338.
Profile of Raine Island, from Jukes (18471, vol. I, p. 339.
Map of Raine Island. The areas in the central guano flat are the seabird survey areas detailed in Table 2.
Topographic profile of Raine Island.
Sediment samples from Raine Island.
Histogram of curved carapace length of turtles measured on the nest, night of 3 November 1973.
10. Section and elevation of the Raine Island Beacon, 1844, after Bateson (1972), p. 201.
List of Tables 1. Visitors to Raine Island.
2. S u l a l e u c o g a s t e r and S u l a d a c t y l a t r a in sample areas of the central guano flat, midday, 3 November 1973.
L i s t o f P l a t e s
(grouped a t t h e end o f t h e p a p e r ) Raine I s l a n d i n 1844, from J u k e s ( 1 8 4 7 ) .
The c e n t r a l guano f l a t from t h e west end o f t h e i s l a n d , l o o k i n g towards t h e Beacon. The r i d g e i n t h e foreground i s t h e s i t e o f t h e o l d guano r a i l w a y .
E a s t e r n end o f t h e c e n t r a l guano f l a t , w i t h Brown and Masked Gannets.
Mounds o f r u b b l e and s t o n e s i n t h e c e n t r a l guano f l a t . Massive beachrock on t h e n o r t h e a s t s h o r e .
Grooved and furrowed beachrock on t h e n o r t h e a s t s h o r e . Beachrock now d i s t a n t from t h e beach on t h e n o r t h s h o r e .
P h o s p h a t i c beachrock unconformably o v e r l y i n g o l d eroded beachrock a t t h e e a s t end o f t h e i s l a n d .
C l i f f s i n phosphate rock a t t h e s o u t h e a s t end o f t h e i s l a n d . I r r e g u l a r lower s u r f a c e o f t h e p h o s p h a t e r o c k , forming c a v e s , on t h e s o u t h s i d e o f t h e i s l a n d . Note t h e n e s t i n g T r o p i c b i r d b e n e a t h t h e overhang.
D e t a i l o f t h e columnar s t r u c t u r e o f t h e phosphate rock.
Detached remnants o f phosphate r o c k , s o u t h s i d e of t h e i s l a n d . Western sand beach, showing e a r l y morning t u r t l e t r a c k s .
T u r t l e n e s t s on t h e beach c r e s t a t t h e west end of t h e i s l a n d . Green T u r t l e on t h e n o r t h e a s t beachrock.
T u r t l e remains i n L e p t u r u s g r a s s l a n d o f t h e h i g h r i d g e .
Shearwater burrows i n f i n e guano a t t h e west end o f t h e c e n t r a l guano f l a t .
Mound i n t h e c e n t r a l guano f l a t w i t h j u v e n i l e L e s s e r F r i g a t e - b i r d s . 19-21. J u v e n i l e L e s s e r F r i g a t e - b i r d s .
22. Brown Gannets l i n i n g t h e beachrock a t t h e e a s t end o f t h e i s l a n d . 23. Brown Gannets on beachrock on t h e n o r t h e a s t s h o r e .
24. Brown Gannets on the nest in the central guano area. Note the twigs outlining the nest.
25. Brown Gannets nesting in the L e p t u r u s grassland of the high ridge. No twigs surround the nest in the vegetated areas.
26-27. Masked Gannets on the nest in the central guano area. The nest is simply a depression in the sand.
28. Hatchling Masked Gannet in the central guano area.
29. Hatchling Masked Gannet with regurgitated flying fish C y p s i l u r u s m e l a n o c e r c u s in a nest in the central guano area.
30-31. Red-footed Gannets on nests built on low A b u t i l o n shrubs on the high ridge at the west end of the island.
Fledgling Red-footed Gannet on the nest at the west end of the island.
Juvenile Red-tailed Tropic-bird under the phosphate cliffs at the east end of the island.
The Beacon and grave at the east end of the island, seen from the south in November 1973.
The Beacon as erected in 1844, from N a u t i c a l M a g a z i n e , vol. 14 (1845), p. 267.
The Beacon in November 1973. The dark area on the lower wall is that repaired by H.M.A.S. G a s c o y n e in 1961.
Inscriptions inside the walls of the Beacon.
The grave of Annie Eliza Ellis.
SAUNDERS 4
Great.
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F i g . 1. The n o r t h e r n G r e a t B a r r i e r R e e f , showing t h e l o c a t i o n o f R a i n e I s l a n d .
NATURAL HISTORY OF RAINE ISLAND, GREAT BARRIER REEF
by D. R. Stoddart1, P. E. Gibbs2, and D. Hopley3
INTRODUCTION
Raine I s l a n d , on t h e n o r t h e r n G r e a t B a r r i e r Reef, i s a s m a l l sand cay 850 m l o n g and up t o 430 m wide. I t was t h e s u b j e c t o f now
c l a s s i c d e s c r i p t i o n s by J o s e p h Beete J u k e s and John MacGillivray d u r i n g t h e voyage o f H.M.S. Fly i n 1843-45, when a s u b s t a n t i a l s t o n e Beacon was b u i l t t h e r e . S e v e r a l o t h e r s c i e n t i f i c p a r t i e s , i n c l u d i n g t h a t o f H.M.S. Challenger, have v i s i t e d t h e i s l a n d , b u t no g e n e r a l a c c o u n t e x i s t s o f i t . T h i s i s t h e more s u r p r i s i n g , s i n c e it i s t h e most i m p o r t a n t b r e e d i n g s t a t i o n f o r t r o p i c a l s e a b i r d s i n A u s t r a l i a , and h a s r e c e n t l y been shown t o be one o f t h e w o r l d ' s l a r g e s t n e s t i n g s i t e s f o r t h e Green T u r t l e .
Much o f Raine was o r i g i n a l l y covered w i t h guano and l i g h t l y cemented p h o s p h a t e r o c k , which formed t h e b a s i s o f a b r i e f b u t c o n s i d e r a b l e mining i n d u s t r y i n 1890-92. Raine i s , i n f a c t ,
i n t e r e s t i n g n o t o n l y i n i t s e l f b u t a l s o a s a r e p r e s e n t a t i v e o f a c l a s s o f s m a l l , s e m i - a r i d guano and phosphate i s l a n d s i n t h e r e e f s e a s . Among t h o s e r e c e n t l y s t u d i e d a r e s e v e r a l i n t h e Amirantes i n t h e w e s t e r n I n d i a n Ocean; Laysan i n t h e Leeward Hawaiian I s l a n d s ; and
s e v e r a l o f t h e s m a l l e r Phoenix I s l a n d s i n t h e c e n t r a l P a c i f i c . Raine i s t h e s m a l l e s t o f a l l o f t h e s e : it i s h a l f t h e s i z e o f McKean and B i r n i e I s l a n d s i n t h e Phoenix group, and h a l f t h e s i z e o f t h e Marie- L o u i s e i n t h e Amirantes. B i r d I s l a n d i n t h e S e y c h e l l e s i s t h r e e t i m e s a s b i g a s R a i n e , and most o f t h e o t h e r phosphate i s l a n d s a r e much l a r g e r . But i n s p i t e o f i t s s m a l l d i m e n s i o n s , Raine i s o f
s u f f i c i e n t i n t e r e s t t o m e r i t b r i n g i n g a l l t h e a v a i l a b l e i n f o r m a t i o n on it t o g e t h e r , t o g e t h e r w i t h new o b s e r v a t i o n s from t h e work o f t h e Royal S o c i e t y and U n i v e r s i t i e s o f Queensland E x p e d i t i o n t o t h e n o r t h e r n G r e a t B a r r i e r Reef i n 1973.
1. Department o f ~ e o ~ r a ~ h ~ , Downing P l a c e , Cambridge, England.
2. Marine B i o l o g i c a l A s s o c i a t i o n o f t h e U . K . , The L a b o r a t o r y , C i t a d e l H i l l , Plymouth, England.
3 . Department o f Geography, James Cook U n i v e r s i t y o f North Queensland, T o w n s v i l l e , A u s t r a l i a .
Manuscript r e c e i v e d August 1980
--
Eds.Table 1. V i s i t o r s t o Raine I s l a n d N
Date Vessel V i s i t o r s Notes References
1815 1843 29-30
J u l y 1844 29 May-mid
September
1845 25 January 1845 A p r i l -
May 1846 5 August 1850 24-25
J u l y 1860 (-1
S u r r y
Thomas Raine F i r s t recorded s i g h t i n gH.M.S.
F l y
Capt.F.P. Blackwood, S h o r t v i s i t J . B. JukesH.M.S.
F l y
Capt.F.P. Blackwood, Shore p a r t y camped t o b u i l d Blackwood 1844a, J . B . J u k e s , J. MacGillivray beacon; v e g e t a b l e gardens 1844b, 1844c,(June o n l y ) , L t J.M.R. I n c e e s t a b l i s h e d . G e o l o g i c a l , J u k e s , 1847, b o t a n i c a l and z o o l o g i c a l work 1871; J.
MacGillivray 1846
H e r o i n e
Capt.M. Mackenzie S h o r t v i s i t ; g o a t s i n t r o d u c e d Mackenzie 1845H.M.S. J . Sweatman
Bramble H e r o i n e
E n c h a n t r e s s
Capt. I'AnsonS h o r t v i s i t
S h o r t v i s i t Wrecked H.M.S. ' Capt. Mangles Denham, S h o r t v i s i t
Salamander
A. R a t t r a ySweatman, MS Anon. 1846 Lack 1953 R a t t r a y 1869 Raine and o t h e r i s l a n d s Crowther 1939 l e a s e d f o r guano d i g g i n g
1865 March H.M.S. Capt. Mangles Denham
Herald
Table 1 continued
Date Vessel Visitors Notes References
1874 31 August H.M.S. Capt. G. Nares, with Short visit, botanical and Campbell 1876;
Challenger H.N. Moseley, J. Murray, zoological collections Spry 1876;
J.Y. Buchanan Swire 1938;
Buchanan 1874;
Forbes 1878;
Sclater and Salvin 1878;
Moseley 1879;
Miers 1886;
Murray 1895
1910 30 October 1911 9-15 July 1913 4-12
December 1957 July 1959 7-14 and
22 February
Beche-de-mer fishery Shore camps Guano digging Shore camps
W.D.K. Macgillivray, Ornithology E.H. Dobbyn
W.R. M'Lennan Ornithology W.D.K. Macgillivray, Ornithology W.R. M'Lennan
D. Attenborough B.B.C. film unit on Raine for 4 days
J. Warharn Ornithology; plants 1961 1 1 H.M.A.S. K.A. Hindwood, K. Keith, Ornithology; plants
November Gascoyne G.F.Mees, I.Thomas
D. Woodland, A. Bartholomai
Ellis 1936 Ellis 1936;
Arundel, MS;
Hutchinson 1950 Macgillivray
1910; North 1912 Macgillivray
1914, 1917, 1918 Macgillivray
1914, 1917, 1918
Warham 1961, 1963, 1959 Hindwood, Keith and Serventy 1963;
Hindwood 1964
W
bP
Table 1 continued
Date Vessel Visitors Notes
-
References
1973 1 - 4 James D.R. Stoddart, P.E. Gibbs, 'Geomorphology, plant This report
November Kirby D. Hopley collection, ornithology, turtles, crabs
Since 1973 there have been several visits to Raine Island by the staff of the National Parks and Wildlife Service of Queensland, the Department of Zoology of James Cook University, and the Australian Institute of Marine Science at Townsville.
GENERAL DESCRIPTION
Raine I s l a n d i s l o c a t e d a t t h e leeward end o f an o v a l p a t c h r e e f 3.5 km l o n g and 0.75 km wide, w i t h an a r e a o f 210 h a , n o r t h o f t h e G r e a t Detached Reef of t h e n o r t h e r n G r e a t B a r r i e r Reef system, and 100 km ENE o f Cape G r e n v i l l e , t h e n e a r e s t p o i n t on t h e Queensland mainland ( F i g u r e s 1 and 2 ) . I t s c o - o r d i n a t e s a r e 11°36'S and
144°01'E. J u k e s (1847) d e s c r i b e d t h e i s l a n d a s 1000 y d s (915 m) l o n g , 500 f t (150 m) wide, and up t o 20 f t (6 m ) h i g h above h i g h w a t e r l e v e l . The c e n t r a l p a r t o f t h e i s l a n d he d e s c r i b e d a s c o v e r e d w i t h a c a p o f c a l c a r e o u s s a n d s t o n e , t e r m i n a t i n g on i t s seaward s i d e s i n a c l i f f 4-5 f t (1.2-1.5 m ) h i g h . The Raine I s l a n d Reef h a s been termed a
" s m a l l c o r a l a t o l l " ( T i z a r d e t a1
.
1885, 11, 530),
b u t i n t h e a b s e n c e o f a lagoon t h i s usage seems i n a p p r o p r i a t e .The f i r s t f u l l d e s c r i p t i o n s o f t h e i s l a n d a r e t h o s e o f J u k e s (1847) and MacGillivray ( 1 8 4 6 ) , b a s e d on o b s e r v a t i o n s made d u r i n g t h e t i m e t h a t a beacon was b e i n g b u i l t on t h e e a s t e r n end o f t h e i s l a n d by Capt F.P. Blackwood and H.M.S. Fly i n 1844. The i s l a n d was
s u b s e q u e n t l y o c c u p i e d d u r i n g 1890-92, when t e n s o f t h o u s a n d s o f t o n s o f phosphate were dug and e x p o r t e d . Twenty y e a r s l a t e r , a t t h e t i m e o f W. M a c g i l l i v r a y ' s v i s i t s , s e a b i r d s were abundant, and t h e i s l a n d i s s t i l l "probably t h e most i m p o r t a n t b r e e d i n g s t a t i o n f o r t r o p i c a l s e a - b i r d s i n A u s t r a l i a n s e a s " (Warham 1961, 7 7 ) . I t i s a l s o a major
n e s t i n g s i t e f o r Green T u r t l e s , though t h i s h a s a t t r a c t e d l e s s a t t e n t i o n i n t h e s c i e n t i f i c l i t e r a t u r e .
No weather r e c o r d s have e v e r been k e p t a t Raine. During A p r i l t o November t h e S o u t h e a s t T r a d e s blow c o n s t a n t l y ; d u r i n g December t o March t h e T r a d e s r e t r e a t t o t h e s o u t h and a r e r e p l a c e d by calms and n o r t h e r l i e s . Most r a i n f a l l o c c u r s d u r i n g t h i s second p e r i o d . Mean a n n u a l r a i n f a l l h a s been e s t i m a t e d by A.T. Bath ( i n Warham 1961) a s 1000 m (40 i n c h e s ) ; t h i s i s v e r y c l o s e t o t h e mean f o r W i l l i s I s l a n d i n t h e C o r a l Sea ( 1 6 ° 1 8 ' S , 1 4 g 0 5 9 ' E ) , where t h e mean a n n u a l r a i n f a l l 1921-1971 was 1098 mm ( F i g u r e 3 ) . R e l i a b i l i t y o f r a i n f a l l a t W i l l i s , and p r o b a b l y a l s o a t R a i n e , i s low; annual t o t a l s a t W i l l i s o v e r t h e p e r i o d o f r e c o r d r a n g e from a minimum o f 240 mm ( i n 1966) t o a maximum o f 2024 m ( i n 1 9 5 9 ) . Overnight dew i s p r o b a b l y an i m p o r t a n t s o u r c e o f m o i s t u r e on t h e s e i s l a n d s .
T i d a l r a n g e h a s been e s t i m a t e d a s 10-12 f t (3.0-3.7 m ) (Blackwood 1844a, 540; F a i r b r i d g e 1950, 3 5 2 ) . Mean t i d a l range a t s p r i n g s f o r i s l a n d s c l o s e r t o t h e mainland between Cape G r e n v i l l e and Cape M e l v i l l e , however, r a n g e s from 5.2 t o 6 . 8 f t (1.6-2.1 m ) , i n c r e a s i n g northwards t o 8 . 4 f t (2.6 m) n e a r Cape York.
GEOLOGY AND GEOMORPHOLOGY Topography
MacGillivray (1846, 1474) d e s c r i b e d t h e f o l l o w i n g main f e a t u r e s o f t h e i s l a n d :
( a ) a s t e e p beach, 20 y a r d s (18 m ) o r more i n width.
( b ) a "more o r l e s s c o n t i n u o u s , low, w a l l - l i k e b o r d e r o f c o r a l r o c k , i t s f a c e s much decomposed by t h e weather, and hollowed o u t i n a s i n g u l a r manner.
...
T h i s r o c k , which ranges from a conglomerate t o a c o a r s e s a n d s t o n e , i s i n g e n e r a l s o f t and crumbles r e a d i l y ....
T h i s bed of sandstone i s n o t more t h a n a few f e e t i n t h i c k n e s s , and e x h i b i t s proof o f i t s r e c e n t formation, by c o n t a i n i n g s h e l l s and fragments o f c o r a l , s p e c i f i c a l l y i d e n t i c a l with l i v i n g i n h a b i t a n t s of t h e r e e f , and o c c a s i o n a l l y eggs o f t u r t l e , a p p a r e n t l y a s i f , w h i l e in situ i n t h e l o o s e sand of what was t h e n a mere sand-bank, some chemical agency had converted t h e whole t o a bed o f s t o n e " . According t o MacGillivray t h e edge o f t h e c l i f f reached a h e i g h t o f 24 f t (7.3 m ) above s e a l e v e l .( c ) a lower c e n t r a l a r e a w i t h a s u r f a c e cover o f " r i c h b l a c k mould"
.
Jukes (1847, I , 339) p r e s e n t e d a schematic s e c t i o n through t h e s e f e a t u r e s .
F i g u r e s 4 and 5 g i v e J u k e s ' s map and p r o f i l e o f Raine I s l a n d a s surveyed i n 1844. F i g u r e 6 i s a map of Raine surveyed by pacing and compass t r a v e r s e i n November 1973, and Figure 7 i s a p r o f i l e a c r o s s t h e c e n t r e of t h e i s l a n d surveyed a t t h a t time. The datum i s i n f e r r e d from t h e measurement of a s t i l l water l e v e l a t a given t i m e , and comparison w i t h t i d e p r e d i c t i o n s f o r S i r C h a r l e s Hardy I s l a n d s , t h e n e a r e s t p l a c e f o r which p r e d i c t i o n s a r e a v a i l a b l e ; t h e S t a n d a r d P o r t i s C a i r n s
(Department o f Harbours and Marine 1973). These d a t a show t h e following topographic f e a t u r e s :
( a ) t h e o u t e r beach, g e n e r a l l y 20 m wide and 5 m h i g h , w i t h i n t e r m i t t e n t beachrock;
( b ) t h e unvegetated beach c r e s t , h o r i z o n t a l o r f a l l i n g s l i g h t l y landwards, 20-25 m wide;
( c ) a low a r e a of t u s s o c k g r a s s l a n d , v a r y i n g i n width from 10 t o 80 m b u t averaging 30-40 m , with average e l e v a t i o n 4 m o r a l i t t l e l e s s ;
( d ) a c l i f f o f cemented sandstone, of i n t r i c a t e o u t l i n e i n d e t a i l and with some i s o l a t e d i s l a n d s o f sandstone i n t h e t u s s o c k g r a s s l a n d , undercut and cavernous, g e n e r a l l y 1-1.5 m h i g h , w i t h t h e o u t e r edge r e a c h i n g a uniform h e i g h t o f 6 m;
( e ) a high r i d g e of uncemented sand, w i t h g r a s s and h e r b c o v e r , w i d e s t i n t h e s o u t h (average 100 m b u t varying from 75 t o
110 m ) and narrower i n t h e n o r t h (average 35 m , varying from 25 t o 75 m ) , w i t h a maximum e l e v a t i o n of about 9 m;
( f ) a c e n t r a l , unvegetated f l a t , w i t h a s u p e r f i c i a l l y - c e m e n t e d s u r f a c e of white guano, with an e l e v a t i o n of 6 m a c c o r d a n t w i t h t h e h e i g h t of t h e p e r i p h e r a l c l i f f edges.
Areas of t h e d i f f e r e n t topographic u n i t s d e r i v e d by p l a n i m e t r y from t h e map i n Figure 5 a r e a s f o l l o w s :
o u t e r beach s l o p e 3.72 ha unvegetated beach c r e s t 3.23 ha tussock g r a s s d e p r e s s i o n 6.75 ha high r i d g e c r e s t 9.58 ha c e n t r a l guano f l a t 4.04 ha
t o t a l a r e a 27.3 ha
These f i g u r e s do n o t i n c l u d e t h e a r e a of i n t e r t i d a l beachrock, which covers a n o t h e r 0.68 ha.
Lithology
The n a t u r e of t h e " c o r a l rock" was f i r s t s t u d i e d by J u k e s , b o t h a t outcrop on h i s f i r s t v i s i t i n 1843 (Jukes 1847, I , 128) and i n q u a r r i e s opened d u r i n g t h e e r e c t i o n of t h e Beacon i n 1844 (1847, I , 337-340).
He found t h a t " t h e s t o n e was made up of small round g r a i n s , some of them a p p a r e n t l y r o l l e d b i t s of c o r a l and s h e l l , b u t many of them e v i d e n t l y c o n c r e t i o n a r y , having c o n c e n t r i c c o a t s
...
n o t u n l i k e some v a r i e t i e s of o o l i t e i n t e x t u r e and appearance. I t c o n t a i n e d l a r g e r fragments of c o r a l and s h e l l s , and some p e b b l e s of pumice, and it y i e l d e do c c a s i o n a l l y a f i n e sand t h a t was n o t c a l c a r e o u s , and which was
probably d e r i v e d from t h e pumice. Some p a r t s of it made a very f a i r b u i l d i n g s t o n e l b u t it g o t s o f t e r below, till it passed downwards i n t o a
c o a r s e r c o r a l sand, unconsolidated and f a l l i n g t o p i e c e s on being touched" (1847, I , 127-128). Excavations f o r t h e q u a r r i e s r e v e a l e d drusy c a v i t i e s with gypsum, many r e c e n t s h e l l s , and one o r two n e s t s of t u r t l e eggs (1847, I , 128, 3401, a s w e l l a s pumice p e b b l e s (1847, I , 3 3 7 ) .
I n 1874 Moseley (1879, 299-300) observed t h a t t h e rock was evenly bedded, t h e bedding being h o r i z o n t a l i n t h e c e n t r e and towards t h e s e a round t h e s h o r e . On t h e n o r t h e a s t s i d e n e a r t h e Beacon he q u o t e s a d i p of seven d e g r e e s . Moseley a l s o c o n t r a s t s t h e white sand, c o n s i s t i n g of s h e l l s , c o r a l s and Foraminifera, of t h e beaches, with t h e a r e a s above high water mark, which were r e d d e r and had a c o n s o l i d a t e d c r u s t (1879, 300)
.
S t r a t i g r a p h y
Two h o l e s were dug d u r i n g t h e Fly e x p e d i t i o n i n t h e c e n t r e o f t h e i s l a n d . One dug by J u k e s t o a d e p t h of 5 f t 1 i n ( 1 . 5 m ) showed t h e f o l l o w i n g s e c t i o n :
0
-
6 i n c h e s ( 0-
15 cm) "Good b l a c k v e g e t a b l e mould"6
-
9 i n c h e s (15-
23 cm) "Stone, brown m o t t l e d w i t h w h i t e , h a r d and c o a r s e g r a i n e d "9
-
25 i n c h e s (23-
63 cm) "Rich m o i s t b l a c k s o i l , l i k e bog- e a r t h "25
-
61 i n c h e s ( 6 3 - 155 cm) "Stone of a l i g h t brown c o l o u r , r a t h e r s o f t , b u t tough, and y i e l d i n g slowly t o t h e p i c k a x e "(Jukes 1847, I , 1 2 7 ) .
M a c G i l l i v r a y ' s p i t t h e f o l l o w i n g y e a r reached a d e p t h of 16 f t ( 4 . 9 m ) , w i t h t h e f o l l o w i n g s e c t i o n :
0
-
3 i n c h e s (0-
7.6 cm) "Fine c o r a l s a n d s t o n e "3
-
12 i n c h e s ( 7 . 6-
30.5 cm) "Moist p u l v e r u l e n t b l a c k e a r t h , resembling p e a t , b u t w i t h o u t any t r a c e o f woody f i b r e s "1
-
13 f e e t ( 3 0 . 5 cm-
3.96 m) "Successive d e p o s i t s , v a r y i n g from c o a r s e c o r a l conglomerate t o unconcreted c a l c a r e o u s sand mixed w i t h a few s m a l ls c a t t e r e d fragments of c o r a l and s h e l l s "
13
-
14 f e e t ( 3 . 9 6 - 4.27 m ) "Masses and l a r g e fragments o f c o r a l (of s p e c i e s now a l i v e on t h e r e e f ) , b l e a c h e d and water-worn, l o o s e l y inbeddedi n c o a r s e s a n d " ; i n f l o w of s e a w a t e r t o o k p l a c e a t t h i s d e p t h .
Sediments
Sediment samples were t a k e n from t h e beach s l o p e , beach berm and high r i d g e on t h e n o r t h , west and s o u t h s i d e s o f t h e i s l a n d ; t h e s e were mechanically a n a l y s e d and components i d e n t i f i e d i n t h e f r a c t i o n c o a r s e r t h a n 250 microns. Components were c l a s s e d a s c o r a l and
coralline algae, molluscs, platey Foraminifera (mainly Marginopora), sphericalForaminifera (including Baculogypsinoides), and Halirneda.
All the samples are remarkably homogeneous. They lie in the size range of coarse sands (0.4
-
0.94); are well sorted (0.3-
0.54); have near symmetrical distributions; and are mainly platykurtic. Twocomponents dominate, molluscan fragments and spheroidal Foraminifera.
Only on the leeward side do coral and coralline algal fragments
contribute significantly to the coarse fraction. Molluscan fragments are more common on the beach and spherical Foraminifera on the berm and ridge, presumably because of the greater mobility of the latter.
Small discrete lenses of platey Foraminifera, Halirneda and pumice were noted at the time of collection. Figure 8 gives sample curves for a beach (curve 1) and high ridge (curve 2) sample.
Two samples were also taken from the centre of the island, one (curve 3 in Figure 8) from the central depression, and one (curve 4) from its surrounding ridge. The central depression sample has a mean size of 1.04, is moderately sorted, symmetrical and leptokurtic; it differs from the beach and berm sediments in its fine tail (coarser than 2.04). The north ridge sample is much finer (mean size 2.34), is poorly sorted (1.254), symmetrical and platykurtic. Its
distribution differs markedly from that of the beach sands.
Interpretation and subsequent observations
Jukes (1847, I, 339-340) believed that the geology of the island could be explained by (1) the formation of a sand cay at the leeward end of the reef; (2) the formation of a crust by solution and
redeposition of calcium carbonate above high water mark: (3) the cessation of accumulation and the cliffing of the lithified material;
and (4) the later resumption of sand accumulation to form the present peripheral sand ridge. The age of the whole island he believed was indicated by the thickness of up to 2 ft of "vegetable mould" in the central depression. Moseley in 1874 compared the rocks of Raine with the "calcareous sand rock" or aeolianite of Bermuda, except that the former was more evenly bedded. Jukesls interpretation is largely confirmed by recent observations, though following the large-scale guano digging of 1890-92 it is no longer possible to be sure that surface features are not of human origin, at least in the central depression.
Many later interpretations, often involving sea-level changes, are less closely related to the facts of lithology and stratigraphy than was Jukesls. Rattray (1869, 303) described Raine as "consisting of hard compact brecciated coral conglomerate, with a shelving beach of coarse coralline and shelly sand, and a scanty superstratum composed of the coral debris sparingly mixed with vegetable matter, and a thin layer of guano1'. He suggested that the present island had been formed beneath the sea and had then undergone emergence, and he termed the island an "extinct" coral reef. Neither Jukes nor MacGillivray had described a coral conglomerate or any raised reef. Several subsequent workers accepted Rattray's inference of emergence, however, from
Agassiz (1898, 124) onwards. Fairbridge (1950, 352) states that Raine
i s " i n p a r t a t l e a s t , an emerged beach rock. With a t i d a l range of 10-12 f e e t and an e x t r a 2-3 f e e t t o include mean swash, an emergence of about 10-11 f e e t i s i n d i c a t e d . Rattray (1869) a l s o mentioned a r a i s e d c o r a l b r e c c i a here. A d e f i n i t e l y emerged c o r a l reef occurs some 12 miles southwest of Raine I s l a n d (Jukes 1847). I t i s 2-3 miles long and 0.25 miles wide, with
P o r i t e s
colonies i n t h e p o s i t i o n of growth 10- 12 f e e t above t h e p r e s e n t reef growth l e v e l " . Fairbridge i n a l a t e r paper .(1967, 403) c a l l e d Raine " t h e only emerged reef i s l a n d on t h e whole o u t e r b a r r i e r ; Jukes observed t h a t it c o n s i s t s of acalcareous a e o l i a n i t e , with an emerged beachrock t e r r a c e here ascribed t o t h e 3 m mid-Holocene s t a g e . The a e o l i a n i t e , by analogy with o t h e r o f f s h o r e occurrences i n A u s t r a l i a
...
i s probably of l a t e g l a c i a l(Wiirm) age, when s e a l e v e l was low enough t o permit wide beaches t o form and dune accumulations t o develop". According t o Bennett (1971, 371, Raine " c o n s i s t s of o l d e r , s o l i d i f i e d r e e f m a t e r i a l formed a t a period when t h e sea l e v e l was h i g h e r " , and t h e stone used f o r t h e Beacon was "quarried o u t of t h e s o l i d r e e f " .
These conclusions e v i d e n t l y go s u b s t a n t i a l l y beyond t h e f a c t s so well recorded by Jukes and MacGillivray i n 1843-44, and a r e not supported by evidence c o l l e c t e d then o r observable now. The 3 m mid-Holocene
"emerged beachrock t e r r a c e " of Fairbridge i s not beachrock, i s not emerged ( i n t h e sense of being now a t a higher l e v e l with r e s p e c t t o s e a l e v e l than when it was formed), and does not stand a t 3 m. The c l i f f edges stand a t 6 m and a r e accordant with t h e c e n t r a l guano f l a t . A l l t h e beachrock a t Raine I s l a n d i s a t low i n t e r t i d a l l e v e l s , and t h e r e i s no evidence t h a t any beachrock t h e r e i s r a i s e d : a radiocarbon d a t e
(ANU-1591) on a
T r i d a c n a
valve from beachrock a t s p r i n g - t i d e swash l e v e l i s 1180+
65 y r B.P. (Polache t a l .
1978, 151). There i s no evidence t h a t t h e main cemented horizon which outcrops i n t h e c l i f f s i s ana e o l i a n i t e (cross-bedding and s i m i l a r sedimentary s t r u c t u r e s seem t o be completely l a c k i n g ) , and a l l t h e evidence i n d i c a t e s t h a t it i s a
s u p e r f i c i a l cementation phenomenon, decreasing with depth, i n t h e way t h a t Jukes envisaged. I t i s a cay sandstone i n which t h e cement i s p a r t l y phosphatic, and cementation probably r e p r e s e n t s a continuing process r a t h e r than a d i s c r e t e event. The " r a i s e d r e e f " 12 miles
southwest of Raine I s l a n d , described by Jukes and t o which Fairbridge r e f e r s , was a l s o v i s i t e d i n 1973: it i s not a r a i s e d r e e f and t h e r e a r e no
P o r i t e s
colonies i n t h e p o s i t i o n of growth: it i s simply ad e p o s i t of l a r g e storm boulders near t h e r e e f edge, a l l now much eroded, and having no s i g n i f i c a n c e with r e s p e c t t o changes i n sea l e v e l .
Phosphate d e p o s i t s
No d e t a i l e d account of t h e Raine I s l a n d phosphates, mined i n t h e c e n t r a l a r e a i n 1890-92, has been published, and no analyses of t h e m a t e r i a l a r e known. According t o Saville-Kent (1893, 1 2 0 ) , " t h e
d e p o s i t s occur under t h r e e d i s t i n c t conditions: F i r s t l y , i n l a y e r s some f i f t e e n inches t h i c k , immediately beneath t h e upper c r u s t of c o r a l
conglomerate, which c o n s t i t u t e s t h e e n c i r c l i n g p l a t e a u described by Mr Jukes; secondly, i n pothole-like hollows i n t h e same l o c a t i o n ; and t h i r d l y , i n t r e n c h - l i k e depressions i n t h e c e n t r a l black e a r t h basin".
The c l i f f s probably r e t a i n much of t h e i r o r i g i n a l appearance, s i n c e t h e mining was c a r r i e d o u t i n t h e c e n t r a l f l a t ; t h e y c l o s e l y resemble comparable c l i f f s on o t h e r i s l a n d s with p h o s p h a t i c cementation, such a s Denis I s l a n d , S e y c h e l l e s ( F r y e r 1910, 18-19, P l a t e 2 ) . The cementation i s g r e a t e s t a t h i g h e r l e v e l s and d i m i n i s h e s w i t h depth;
t h e lower s u r f a c e of t h e cemented h o r i z o n i s i r r e g u l a r , and forms a s e r i e s o f downward-directed l o b e s and p i l l a r s . These probably i n d i c a t e d i f f e r e n t i a l p e r m e a b i l i t y i n t h e o r i g i n a l l y uncemented sands. T.P.
S c o f f i n h a s examined specimens from t h e upper p a r t of t h e c l i f f s a s p a r t o f a wider s t u d y of c o r a l i s l a n d phosphates. The g r a i n s i n t h e sands a r e of v a r i a b l e o r i g i n : Foraminifera 40%, Halimeda 30%, c o r a l l o % , mollusc
l o % ,
unknown 10%. Phosphatic cement o c c u r s a s a wavy t h i n f i l m w i t h laminated s t r u c t u r e c o a t i n g t h e i n d i v i d u a l g r a i n s ; t h e g r a i n sthemselves have been a l t e r e d c e n t r i p e t a l l y f o r d i s t a n c e s of a few microns from t h e g r a i n margins. The phosphate mineral i s
h y d r o x y l a p a t i t e ; t h e o t h e r main mineral p r e s e n t i s a r a g o n i t e , with a t r a c e o f c a l c i t e . The presence of a r a g o n i t e s u g g e s t s a younge age f o r t h e m a t e r i a l . Chemical composition i s 31.0% P 2 0 5 , 54.0% CaO.
WATER SUPPLY
There i s no s t a n d i n g s u r f a c e water on Raine, e x c e p t p o s s i b l y f o r a few days immediately a f t e r storms. During t h e F l y e x p e d i t i o n water was imported from S i r C h a r l e s Hardy's I s l a n d s f o r t h e men b u i l d i n g t h e Beacon. J u k e s (1847, 11, 266) s a y s t h a t "one o r two w e l l s were sunk i n t h e i s l a n d , b u t no f r e s h water was procured; although i n one of t h e w e l l s , a t a depth of 16 f e e t , t h e water was o n l y b r a c k i s h , and could be used t o s l a c k t h e l i m e , although v e r y u n p a l a t a b l e t o t h e t a s t e " . Arundel i n 1890 had t o c o n s t r u c t a seawater d i s t i l l a t i o n p l a n t f o r h i s work f o r c e . Warham (1961, 78-79) a l s o s t a t e s t h a t t h e r e i s no f r e s h water and t h a t " v a r i o u s a t t e m p t s t o s t r i k e it by d i g g i n g i n t h e p a s t have f a i l e d " .
A carved i n s c r i p t i o n on t h e i n s i d e of t h e w a l l s of t h e Beacon, however, a p p a r e n t l y of mid-nineteenthcenturydate (it i s mentioned i n A r u n d e l ' s d i a r y i n 1 8 9 0 ) , s t a t e s t h a t f r e s h water can be o b t a i n e d a t a depth of 7 f e e t .
VEGETATION AND FLORA
The v e g e t a t i o n of Raine I s l a n d c o n s i s t s of low s h r u b s , h e r b s and g r a s s e s ; t h e r e a r e no t r e e s . To Blackwood (1844a, 539) it was t h e
" q u a n t i t y o f c o a r s e green v e g e t a t i o n on it" which d i s t i n g u i s h e d Raine from most of t h e o t h e r s m a l l sand c a y s i n t h i s n o r t h e r n r e e f a r e a ; he was c l e a r l y t h i n k i n g o f unvegetated sand cays i n t h e v i c i n i t y , such a s t h o s e on Ashmore Reef.
Jukes (1847, I , 127) d e s c r i b e d "a low shrubby v e g e t a t i o n , p a r t l y o f r e e d - l i k e o r u m b e l l i f e r o u s p l a n t s , and p a r t l y w i t h a c l o s e green c a r p e t o f a p l a n t w i t h s u c c u l e n t l e a v e s and stem, which we subsequently found was good t o e a t , and s o went w i t h u s by t h e name of 'spinach"'
( t h i s was probably P o r t u l a c a ) . MacGillivray (1846, 1475) gave a f u l l e r account, though unfortunately unsupported by specimens: "Of t h e Botany of t h e i s l e t I can give but a very meagre account, f o r a c o l l e c t i o n of about twenty s p e c i e s , found by me, u n f o r t u n a t e l y went t o decay f o r want of a proper p l a c e of s t o r a g e on board s h i p . Several of t h e s e s p e c i e s I have elsewhere observed on t h e main land of New Holland;
among o t h e r s , a long, t r a i l i n g , woody p l a n t with conspicuous yellow blossoms [probably Tribulus c i s t o i d e s ]
,
and a l a r g e white-flowered convolvulus [probably Ipomoea macranthal. Two s p e c i e s , very abundant, on t h e i s l a n d , were used by us a s vegetables, one of them under t h e name of spinach [ P o r t u l a c a ] , f o r which it was considered a very f a i r s u b s t i t u t e , and a s such served o u t t o t h e s h i p ' s company. Most of t h e p l a n t s of t h e i s l a n d a r e more o r l e s s succulent; t h e r e i s b u t oneshrub, a s l e n d e r Acacia, f i v e o r s i x f e e t high, with small yellow flowers [probably Sesbania]". The surrounding sand a r e a had "a few s c a t t e r e d t u f t s of g r a s s and o t h e r herbage" (MacGillivray 1846, 1474).
A v a r i e t y of c u l t i v a t e d p l a n t s was introduced during t h e Fly expedition and during t h e v i s i t of t h e Heroine i n 1845; they a r e d e s c r i b e d l a t e r . The Challenger Expedition i n 1874 recorded 11 s p e c i e s of flowering p l a n t s , including two g r a s s e s . They noted fungi on dung, b u t no
mosses, f e r n s o r l i c h e n s . There was a l s o no t r a c e of t h e Fly vegetable gardens o r of o t h e r i n t r o d u c t i o n s . No s p e c i e s l i s t appears t o have been published from t h e s e c o l l e c t i o n s (Moseley 1879).
In 1910 W. Macgillivray (1910, 2 2 4 ) found "a coarse g r a s s , a kind of pig-face weed, and a low p e r e n n i a l shrub of h o r i z o n t a l growth, not more than 1 t o 1* f e e t from t h e groundanywhereland bearing grey-green l e a v e s and a yellow flower". These were probably Lepturus repens, Portulaca sp.
,
and Tribul u s c i s t o i d e s , r e s p e c t i v e l y .In February 1959, a f t e r good r a i n s , Warham (1961, 78) found only s i x s p e c i e s of flowering p l a n t s , "the p r i n c i p a l one being a kind of mallow (Abutilon graveolus o r i n d i c a ) which was flowering, a spinach-
l i k e amaranth (Amaranthus v i r i d i s ) and a low bushy p l a n t Tribulus c i s t o i d e s . This bore orange flowers and i s probably the ' a c a c i a ' of t h e e a r l y v i s i t o r s of t h e i s l a n d [Abutilon and Tribulus appear confused i n t h i s account]. Two g r a s s e s a l s o f l o u r i s h e d : Eleusine i n d i c a , an introduced s p e c i e s , and Lepturus repens, a n a t i v e p l a n t . This grew q u i t e t h i c k l y on t h e dunes on t h e south-east s i d e of t h e i s l a n d . A low succulent a l s o grew around the edges of t h e c e n t r a l depression
[probably Portulaca s p . ] . None of t h e s e p l a n t s was more than two f e e t high".
The only published l i s t of Raine I s l a n d p l a n t s appears t o be t h a t of Hindwood e t a 1
.
(1963, 4 4 ),
based on c o l l e c t i o n s made i n November1961 and lodged i n t h e Queensland Herbarium, Brisbane, and t h e Division of P l a n t I n d u s t r y , C.S.I.R.O., Canberra. Six s p e c i e s a r e recorded, and it i s l i k e l y from Warham's records two y e a r s e a r l i e r t h a t o t h e r s were missed.
p l a n t s were c o l l e c t e d i n 1973 a n d w e r e i d e n t i f i e d by M i s s S.
Reynolds a t t h e Queensland Herbarium, B r i s b a n e . The f o l l o w i n g l i s t i n c l u d e s t h e p l a n t s c i t e d by Hindwood
e t
a l . ( 1 9 6 3 ) .Gramineae
E l e u s i n e i n d i c a ( L . ) G a e r t n .
S t o d d a r t 5061. Also c i t e d by Warham (1961, 78)
.
L e p t u r u s r e p e n s R . B r . c f . v a r . r e p e n s
S t o d d a r t 5051, 5059. Also c i t e d by Warham (1961, 78) and Hindwood
e t
a l . (1963, 4 4 ) .Nyctaginaceae
~ o e r h a v i a s p
.
S t o d d a r t 5054 (specimen l o s t ) . H i n d w o o d
e t
a l . (1963, 44) a l s o c i t e B o e r h a v i a t e t r a n d r a F o r s t . , b u t t h e specimen c o l l e c t e d i n 1973 i s n o t t h i s s p e c i e s .Amaranthaceae
A c h y r a n t h e s a s p e r a L.
S t o d d a r t 5053. C i t e d by Hindwood e t a l . (1963, 4 4 ) . A m a r a n t h u s v i r i d i s L.
S t o d d a r t 5057, 5058? Warham (1961, 78) a l s o c i t e s A m a r a n t h u s v i r i d i s .
P o r t u l a c a c e a e
P o r t u l a c a o l e r a c e a L. ( s e n s u l a t o )
S t o d d a r t 5056. P o s s i b l y t h e p l a n t mentioned by W . M a c g i l l i v r a y (1910, 224) and Warham (1961, 7 8 ) . C r u c i f e r a e
C o r o n o p u s i n t e g r i f o l i u s Spreng.
S t o d d a r t 5060 Leguminosae
S e s b a n i a c f
.
a c u l e a t a P o i r.
S t o d d a r t 5050. S e s b a n i a a c u l e a t a i s c i t e d by Hindwood
e t
a l . (1963, 4 4 ) .Zygophyllaceae
T r i b u l u s c i s t o i d e s L.
S t o d d a r t 5055. C i t e d by Warham (1961, 78) and Hindwood
e t
a l . (1963, 4 4 ) ; p o s s i b l y t h e p l a n t mentioned by M a c G i l l i v r a y (1846, 1 4 7 5 ) .Malvaceae
A b u t i l o n a s i a t i c u m v a r . a u s t r a l i e n s e (Noch. e x B r i t t . ) Fosb.
S t o d d a r t 5052. C i t e d a s A. i n d i c u m ( L . ) Sweet by Hindwood
e t
a l . (1963, 4 4 ) ; p r o b a b l y t h e p l a n t s mentioned by W. M a c g i l l i v r a y (1910, 224) and Warham(1961, 7 8 ) .
Convolvulaceae
Ipomoea macrantha R . and S.
Not c o l l e c t e d i n 1973 o r by Hindwood et al. ( 1 9 6 3 ) . P o s s i b l y t h e p l a n t mentioned by M a c G i l l i v r a y (1846, 1475)
.
INVERTEBRATES
Most o f t h e c o l l e c t i o n s o f i n v e r t e b r a t e s made a t and n e a r Raine I s l a n d have been o f m a r i n e a n i m a l s d u r i n g t h e Challenger E x p e d i t i o n . These a r e l i s t e d by Murray ( 1 8 9 5 , 682-688); t h e y comprise mainly s p e c i e s o f O s t r a c o d a , Mollusca and F o r a m i n i f e r a , w i t h o n l y a few l a n d o r s h o r e a n i m a l s .
The most c o n s p i c u o u s , i n d e e d t h e o n l y , s e m i - t e r r e s t r i a l c r u s t a c e a n i s t h e g h o s t c r a b Ocypode. Moseley c o l l e c t e d a s i n g l e male specimen o f 0 . ceratophthalma ( P a l l a s ) , r e c o r d e d by Miers (1886, 238-239). I n 1973 t h e p o p u l a t i o n was p r e d o m i n a n t l y 0 . ceratophthalma w i t h a few 0.
cordimana Desmarest, t h e two s p e c i e s b e i n g r e p r e s e n t e d i n a sample o f 60 i n d i v i d u a l s i n a r a t i o o f 6 . 5 : 1 . C o e n o b i t i d h e r m i t c r a b s , e l s e w h e r e common on guano i s l a n d s i n t h e c e n t r a l P a c i f i c and I n d i a n Oceans and a l s o i n t h e C a r i b b e a n , a p p e a r t o be c o m p l e t e l y a b s e n t on Raine and o t h e r G r e a t B a r r i e r Reef i s l a n d s . Mole-crabs o f t h e genus Hippa i n h a b i t t h e c o a r s e s a n d s o f t h e lower b e a c h l e v e l s ; a l t h o u g h H. pacifica (Dana) was t h e o n l y s p e c i e s c o l l e c t e d i n 1973, it seems l i k e l y t h a t H. celaeno (de Man), a commoner s p e c i e s on o t h e r r e e f i s l a n d s i n t h e r e g i o n ( s e e Gibbs 1 9 7 8 ) , i s p r e s e n t a l s o .
Among i n s e c t s , M a c G i l l i v r a y (1846) n o t e d a l a r g e s c a r a b , C o l e o p t e r a i n c l u d i n g Hister, Necrobia c f . ruficollis, and Dermestes murinus;
Pimelia; and i x o d i d t i c k s . Moseley (1879, 302) found a n e a r w i g
Forficula under s t o n e s and a v e r y common l o c u s t Acridium. No f u r t h e r i n v e r t e b r a t e c o l l e c t i o n s a p p e a r t o have been made.
MARINE TURTLES
The Green T u r t l e n e s t i n g s e a s o n a t Raine I s l a n d i s c o n c e n t r a t e d from October t o December; v i s i t o r s o u t s i d e t h e s e t i m e s have u s u a l l y made few t u r t l e o b s e r v a t i o n s . P a r s o n s (1962) i n h i s s t a n d a r d work on
t h e Green T u r t l e makes no mention o f Raine I s l a n d , and w h i l e B u s t a r d (1972) i n c l u d e s Raine I s l a n d i n a map a s a n i m p o r t a n t n e s t i n g s i t e h e makes no mention o f it i n h i s t e x t . Yet R a i n e i s c e r t a i n l y one o f t h e l a r g e s t Green T u r t l e n e s t i n g s i t e s i n t h e w o r l d , and c o u l d be t h e
l a r g e s t r e m a i n i n g s t i l l u n d i s t u r b e d by man.
J u k e s ' s f i r s t v i s i t i n J u l y 1843 produced few r e c o r d s . "There w e r e a few t u r t l e t r a c k s on t h e b e a c h , b u t w e d i d n o t s u c c e e d i n t a k i n g a n y , though many dead o n e s were s c a t t e r e d a b o u t t h e i s l a n d " , e s p e c i a l l y a t t h e f o o t o f t h e c l i f f ( J u k e s 1847, I , 1 3 0 ) . During t h e 1844 v i s i t , M a c G i l l i v r a y (1846, 1479) found t h a t " d u r i n g t h e months o f J u n e , J u l y
and August, t h e t u r t l e o c c u r r e d a t i r r e g u l a r i n t e r v a l s , g e n e r a l l y
s i n g l y , b u t i n t h e b e g i n n i n g o f September t h e y became more numerous".
I n t h e f o l l o w i n g y e a r a p a r t y from t h e
B r a m b l e
found t h e c l i f f s and q u a r r i e s " f u l l o f t h e remains [of t u r t l e s ]...
who had f a l l e n o v e r on t h e i r backs and p e r i s h e d m i s e r a b l y " . They took 14 t u r t l e by t u r n i n g them on t h e beaches a t n i g h t , some of them b e i n g of 250-300 l b s weight( r o u g h l y 110-140 k g ) . Sweatman (MS, 94-95) g i v e s a g r a p h i c account o f t a k i n g t u r t l e d u r i n g t h i s v i s i t . Mackenzie (1845, 4 9 4 ) , c a l l i n g w i t h t h e
Heroine
on 25 J a n u a r y 1845, " o b t a i n e d f o u r t e e n l a r g e t u r t l e s , e a c h a v e r a g i n g f o u r cwt [ c a 200 k g ] " . I n August 1874 t h eC h a l l e n g e r
found o n l y t h e c a r a p a c e s o f numerous dead t u r t l e s (Moseley 1879, 3 0 2 ) .C o n v e r s e l y , M a c g i l l i v r a y (1910, 2 2 4 ) , on 30 October 1910, found
" g r e a t numbers of t u r t l e s
...
on t h e beach and i n t h e shallow water round t h e b o a t " . On 4 December 1913 he found t h a t "about t h i r t y t u r t l e s were c r a w l i n g up t h e beach n e a r where we l a n d e d , and t h e s h a l l o w w a t e r c o n t a i n e d hundreds o f them", coming a s h o r e a t n i g h t t o n e s t ( M a c g i l l i v r a y 1917, 6 7 ) .During t h e
F l y
v i s i t , MacGillivray (1846, 1478-1479) noted t h a t a l l t h e t u r t l e s e e n were Green,C h e l o n i a m y d a s ,
and t h a t t h e y l a i d c l u t c h e s o f a t l e a s t f i f t y e g g s . He found t h a t t h e h a t c h i n g young s u f f e r e d p r e d a t i o n by f r i g a t e b i r d s and s o o t y t e r n s , and s i x t y y e a r s l a t e r M a c g i l l i v r a y (1917, 8 4 ) r e c o r d e d p r e d a t i o n o f eggs by C r e s t e d TernS t e r n a b e r g i i
and S i l v e r G u l lL a r u s n o v a e - h o l l a n d i a e .
Green T u r t l e were n e s t i n g d u r i n g t h e v i s i t t o Raine I s l a n d i n 1973. Tracks were counted round t h e i s l a n d each morning. Measured a t t h e f o o t o f t h e beach, t h e p e r i m e t e r o f t h e i s l a n d occupied by sand
( i n c l u d i n g t h e low and d i s c o n t i n u o u s narrow beachrock o f t h e n o r t h e r n c o a s t ) t o t a l s 1600 m , and t h a t occupied by beachrock 500 m (76 and 24%
r e s p e c t i v e l y ) . Numbers c o u n t e d on t h e beach o n l y were a s f o l l o w s : T r a c k s Animals
Night o f 31 October 324 162
1 November 245 12 3
2 November 2 30 115
3 November 2 70 135
During t h e n i g h t o f 3 November, a n i m a l s were a l s o counted on t h e n e s t b o t h on sandy beaches and a l s o i n l a n d from beachrock s h o r e s . The r a t i o o f t r a c k s : a n i m a l s on t h e beaches can t h e n be used t o i n f e r t h e number o f t r a c k s which might b e e x p e c t e d on t h e beachrock s h o r e s , t o g i v e an e s t i m a t e o f t h e t o t a l number coming a s h o r e f o r t h e whole i s l a n d on t h a t n i g h t . The r e s u l t s a r e :
Beach Beachrock Whole i s l a n d
( a ) Animals counted on n e s t 87 38 125
( b ) Numbers i n f e r r e d from t r a c k s 13 5
R a t i o ( b ) : ( a ) 1.55
I n f e r r e d t o t a l numbers 135 59
I n subsequent s u r v e y s , B i r t l e s (1978) e s t i m a t e d t h e numbers o f n e s t i n g t u r t l e s a t 11,800 i n 1974, 50 i n 1975, 1000 maximum i n 1976, and
50-100 i n 1977. Kowarsky (1978) a l s o made ground and a e r i a l o b s e r v a t i o n s i n J a n u a r y 1976, b u t a l t h o u g h t r a c k s were numerous he
c o u l d n o t make any e s t i m a t e of numbers. For comparison, a t I l e Europa, Mozambique Channel, sometimes s t a t e d t o be t h e l a r g e s t Green T u r t l e colony i n t h e w o r l d , Hughes (1974) e s t i m a t e d 5,000 emergences a y e a r , and Servan (1976) 1300 a y e a r .
The prime n e s t i n g h a b i t a t on Raine i s t h e u n v e g e t a t e d s a n d a r e a s of t h e beach c r e s t , though a c o n s i d e r a b l e number of t u r t l e s do n e s t i n t h e o u t e r L e p t u r u s t u s s o c k g r a s s l a n d between t h e beach and t h e c l i f f s . P l a n i m e t r i c measurements on F i g u r e 5 i n d i c a t e a t o t a l a r e a o f
u n v e g e t a t e d beach c r e s t o f 32,300 s q m. A t u r t l e 1 m l o n g r e q u i r e s an a r e a of n o t l e s s t h a n 1.54 s q m f o r i t s n e s t i n g d e p r e s s i o n . Hence t h e r e a r e a p p r o x i m a t e l y 21,000 p o t e n t i a l non-overlapping n e s t s i t e s i n t h e beach c r e s t a r e a . Two hundred t u r t l e s n e s t i n g i n one n i g h t would have 161.5 s q m each i n which t o choose a n e s t i n g s i t e . Each s i t e would have roughly 1 chance i n 100 of b e i n g s e l e c t e d . These
c a l c u l a t i o n s g i v e some i d e a of t h e p o s s i b l e p o t e n t i a l s i z e o f t h e Raine I s l a n d colony. Elsewhere on t h e G r e a t B a r r i e r Reef, on v e g e t a t e d i s l a n d s , t h e s i z e o f n e s t i n g a r e a a v a i l a b l e i s a l i m i t i n g f a c t o r i n t h e number of s u c c e s s f u l n e s t i n g s ( B u s t a r d and T o g n e t t i 1 9 6 9 ) : a t Raine
I s l a n d t h i s i s u n l i k e l y t o be s o . Kowarsky (1978) q u o t e s a c l u t c h s i z e a t Raine o f 105.8
+
22.0 eggs ( n = 6).The curved c a r a p a c e l e n g t h o f f e m a l e s on t h e n e s t was a l s o
measured on t h e n i g h t of 3 November, and F i g u r e 9 p r e s e n t s a h i s t o g r a m of t h e r e s u l t s . 124 a n i m a l s were measured. The mean l e n g t h was
109 cm, s t a n d a r d d e v i a t i o n 5.29 cm; t h e s m a l l e s t measured was 90 cm l o n g , and t h e l a r g e s t 122 cm. B u s t a r d (1972, 138-141) q u o t e s a v e r a g e f i g u r e s of 107 cm curved l e n g t h f o r G r e a t B a r r i e r Reef Green T u r t l e s , and r a n g e s of 89-127 cm. Curved l e n g t h c a n be c o n v e r t e d t o s t r a i g h t l e n g t h u s i n g t h e formula d e r i v e d f o r Aldabra t u r t l e s by F r a z i e r (1971, 3 9 0 ) , and t h e c a l c u l a t e d s t r a i g h t l e n g t h s t h e n used t o compare
p o p u l a t i o n s i n d i f f e r e n t p a r t s of t h e world. The Raine I s l a n d
t u r t l e s a r e v e r y s i m i l a r i n s i z e t o t h o s e of Aldabra, markedly b i g g e r t h a n t h o s e of Ceylon, Yemen and Sarawak, and markedly s m a l l e r t h a n t h o s e of Guyana, Ascension I s l a n d and Surinam ( d a t a l i s t e d by F r a z i e r 1971, 380, and Servan 1976, 4 2 4 ) . I n a d d i t i o n t o t h e 1973 d a t a , Kowarsky
(1978) g i v e s mean s t r a i g h t l e n g t h of 100.2
+
5 . 5 and mean curved l e n g t h 108.6+
5 . 1 cm f o r f o u r i n d i v i d u a l s a t Raine I s l a n d .While measuring t h e t u r t l e s i n 1973 it was o b s e r v e d t h a t a n i m a l s d i f f e r e d markedly i n d e g r e e of c u r v a t u r e o f c a r a p a c e . I n some t h e c u r v a t u r e was s o s h a l l o w t h a t i t i s p o s s i b l e t h e y belong t o C h e l o n i a d e p r e s s a Garman, t h e F l a t b a c k T u r t l e ( B u s t a r d 1972, 74-88) r a t h e r t h a n t o C h e l o n i a mydas L .
According t o Limpus ( 1 9 7 8 ) , t a g g e d t u r t l e s from Raine I s l a n d have been r e c o v e r e d from s o u t h o f Cooktown, Queensland, t h r o u g h t h e T o r r e s S t r a i t and s o u t h e r n Papua New Guinea t o Aru I s l a n d , I n d o n e s i a .
I n a d d i t i o n t o t h e Green T u r t l e , Boulenger (1889) a l s o r e c o r d s t h e Hawksbill Eretmochelys imbricata ( a s Chelone imbricata) from R a i n e , b u t no s u b s e q u e n t r e c o r d s a r e known.
BIRDS
R a i n e I s l a n d i s a major b r e e d i n g s t a t i o n f o r s e a b i r d s , and
p r o b a b l y t h e most i m p o r t a n t i n t e r m s o f numbers o f s p e c i e s on t h e G r e a t B a r r i e r R e e f . I t h a s l a r g e b r e e d i n g c o l o n i e s o f Brown and Masked G a n n e t s , Noddies, S o o t y T e r n s , and Wedge-tailed S h e a r w a t e r s . I t i s a l s o a b r e e d i n g s i t e f o r t h e R e d - t a i l e d T r o p i c - b i r d and t h e L e s s e r F r i g a t e - b i r d , o t h e r w i s e r a r e on t h e G r e a t B a r r i e r Reef. There a r e no comparable s e a b i r d - b r e e d i n g s t a t i o n s ( e x c e p t f o r c o l o n i e s o f Noddies and Sooty T e r n s ) between R a i n e and t h e C a p r i c o r n and Bunker I s l a n d s a t t h e s o u t h e r n end o f t h e R e e f . There i s a l s o a r e s i d e n t l a n d b i r d , t h e Banded L a n d r a i l , many s h o r e b i r d s , and a number o f m i g r a n t s and v a g r a n t s r e c o r d e d .
The f i r s t o r n i t h o l o g i c a l o b s e r v a t i o n s were t h o s e o f J u k e s and M a c G i l l i v r a y i n 1843-44 d u r i n g t h e v i s i t s o f t h e Fly. Moseley made o b s e r v a t i o n s and c o l l e c t i o n s d u r i n g t h e Challenger v i s i t i n August 1874.
The f i r s t e x t e n s i v e r e c o r d s a r e t h o s e o f M a c G i l l i v r a y and M'Lennan i n 1910, 1911 and 1913. The most d e t a i l e d a c c o u n t o f Raine I s l a n d b i r d s i s t h a t o f Warham ( 1 9 6 1 ) , f o l l o w i n g h i s v i s i t i n F e b r u a r y 1959.
Warham's l i s t i s u s e d a s t h e b a s i s f o r t h e p r e s e n t a c c o u n t , though nomenclature f o l l o w s S t o r r ( 1 9 7 3 ) ; w e a r e most g r a t e f u l t o C.W. Benson f o r h i s a s s i s t a n c e w i t h and comments on t h i s l i s t . F o l l o w i n g Warham, K.A. Hindwood and o t h e r s a l s o v i s i t e d R a i n e d u r i n g a s u r v e y o f s e a b i r d s o f t h e C o r a l Sea i n November 1961; t h e i r r e c o r d s a r e a l s o i n c o r p o r a t e d h e r e .
I n a d d i t i o n t o t h e b i r d s l i s t e d h e r e , E l l i s (1937, 179) a l s o r e c o r d s " s e v e r a l long-legged and l o n g - b i l l e d i b i s e s " , " t h r e e common crows", and " s e v e r a l d i m i n u t i v e hawks". M a c G i l l i v r a y (1846) a l s o r e c o r d s s e v e r a l s p e c i e s of u n c e r t a i n synonymy, i n c l u d i n g Charadrius virqinianus, Thalasseus strenuus, Callocalia arborea, and Porzana.
Ducula spilorrhoa spilorrhoa (Gray) T o r r e s S t r a i t Pigeon One m i g r a n t b i r d i s r e c o r d e d ( a s Myristicivora spilorrhoa) by E l l i s (1936, 178)
.
Rallus philippensis yorki (Mathews) Banded L a n d r a i l Recorded a s Rallus philippensis? by M a c G i l l i v r a y (1846, 1476-77) i n 1844, and s u b s e q u e n t l y f i g u r e d by Gould (1848, V I , 7 6 ) . I t was " v e r y abundant a l l o v e r t h e i s l a n d " , under v e g e t a t i o n , b e n e a t h o v e r h a n g s , and i n s h e a r w a t e r burrows. M a c G i l l i v r a y found it v e r y wary, though it r a n and r a r e l y f l e w . H e c a u g h t " g r e a t numbers" (up t o 4 5 i n a d a y ) w i t h h i s dog.
I n 1874 Moseley c o l l e c t e d two males and one female (Forbes 1878).
Under t h e name Rallus pectoralis Moseley d e s c r i b e d it a s tame, and e a s i l y knocked down w i t h s t i c k s o r caught by hand. I n August t h e r e were f u l l - f l e d g e d young (Moseley 1879, 3 0 1 ) . On t h e b a s i s o f t h i s r e c o r d Kikkawa ( 1 9 7 6 ) l i s t s R. pectoralis Lewin Water R a i l a s a s e p a r a t e s p e c i e s ( b u t s e e d i s c u s s i o n below).
During 1890-92 t h e r e were i n i t i a l l y l a r g e numbers, b u t "a welcome a d d i t i o n t o t h e t a b l e t h e y were. T h e i r numbers were m a t e r i a l l y
l e s s e n e d d u r i n g o u r occupation of t h e i s l a n d , b u t some were l e f t t o c a r r y on t h e r e s t o c k i n g " ( E l l i s 1937, 177-178). M a c g i l l i v r a y i n October 1910 simply r e c o r d s "numbers" running over t h e i s l a n d (1910, 226)
.
There a r e no f u r t h e r r e c o r d s u n t i l Warham's v i s i t i n February 1959.
I t was t h e n "very numerous and
...
o f t e n seen i n t h e daytime s k u l k i n g among t h e herbage o r running about beneath t h e c a v e s and c a v i t i e s under t h e c l i f f s . A t n i g h t they s p r e a d o u t a l l over t h e i s l a n d and were o f t e n seen on t h e dunes where t h e y f e d on t u r t l e eggs exposed by t h e subsequent d i g g i n g s o f o t h e r t u r t l e s ....
Two n e s t s were d i s c o v e r e d...
t h e i r eggs b e i n g hidden beneath t h e t h i c k herbage" (Warham 1961, 8 3 ) . Warham a l s o noted t h a t t h e r a i l s could be approached c l o s e l y a t n i g h t . The d e s c r i p t i o n a g r e e s w i t h t h e s i t u a t i o n i n 1973, e x c e p t t h a t dead b i r d s were numerous on t h e ground, b o t h on t h e high r i d g e and beneath t h e c l i f f s . S e v e r a l o f t h e s e dead b i r d s were c o l l e c t e d . Two males were a l s o c o l l e c t e d by Hindwood e t a l . (1963, 38) i n November 1961; one i s i n t h e Western A u s t r a l i a n Museum (no. A87551 and t h e o t h e r i n t h e C.S.I.R.O. c o l l e c t i o n (no. CSIRO 3 0 1 ) .S t o r r (1973) s t a t e s t h a t R. p. yorki, a s m a l l , d a r k r a c e , i s v e r y common i n t h e T o r r e s S t r a i t s i s l a n d s and on low i s l a n d s o f t h e
Queensland c o a s t from Pandora Cay t o Lady Musgrave I s l a n d ( i n 1973 we observed r a i l s on Hope I s l a n d s , T u r t l e I s l a n d s , Three I s l e s , and P e l i c a n I s l a n d ) . A second r a c e , R. p. pectoralis, i s of u n c e r t a i n s t a t u s b u t e v i d e n t l y r a r e i n Queensland. The p e c t o r a l band i n yorki i s d a r k e r ( c h e s t n u t cinnamon r a t h e r t h a n p a l e cinnamon) and narrower
(6-10 mm wide r a t h e r t h a n 14-30 m m ) . C . J . O . H a r r i s o n h a s k i n d l y r e - examined specimens from Raine I s l a n d i n t h e B r i t i s h Museum ( N a t u r a l H i s t o r y ) , t o g e t h e r w i t h t h o s e t a k e n a s dead b i r d s i n 1973. The t h r e e Challenger specimens which i n c l u d e d a young b i r d , s u g g e s t i n g r e c e n t b r e e d i n g , a r e of t h e s o u t h e r n r a c e , pectoralis. S.A. P a r k e r h a s examined Raine I s l a n d specimens i n A u s t r a l i a n museums, and found them t o be yorki, and t h e specimens t a k e n i n 1973 were a l s o of t h i s form.
H a r r i s o n comments: " I t seems p r o b a b l e from t h e e v i d e n c e t h a t b o t h A u s t r a l i a n r a c e s a r e migratory t o some d e g r e e , and t h a t both could p o t e n t i a l l y occur i n Raine I s l a n d i n passage. There a r e o t h e r
r e f e r e n c e s i n l i t e r a t u r e t o t h e s p e c i e s b r e e d i n g on t h e i s l a n d b u t no s u b s p e c i f i c r e c o g n i t i o n of them. There i s no c l e a r i n d i c a t i o n o f t h e s t a t u s o r o r i g i n o f t h e b i r d s which do o r d i d ( i n t e r m i t t e n t l y ? ) b r e e d on t h e i s l a n d . Dead b o d i e s might be t h o s e o f f a i l e d m i g r a n t s . "
