ATOLL BUTLETIN - Smithsonian Institution

ATOLL RESEARCH

BUTLETIN

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NO.

103

Observations on t h e b i r d s of French F r i g a t e Shoal and

Kure

A t o l l by

Miklos D. F. Udvardy and Richard E. Warner

Issued by

TKE PACIFIC SCIENCE BOARD

National Academy of Sciences--National Research Council Washington,

D.

C .

September 30, 1364

Oboervations on t h e b i r d s o f French F r i g a t e S h o a l a ~ d I h r e A t o l l

by

Miklos 3. F. Udvardy and Richard C. Warner

g

Through t h e c o u r t e s y of t h e United S t a t e s Coast Guard t h e a t h o r s s p e n t an hour on September 2,

1961

on Tern I s l a n d , French F r i g a t e S h o a l , and v i s i t e d Kure A t o l l from September 1 2 t o 1 4 ,

1961,

d u r i n g t h e Harold J.

Coolidge Xxpedition t o t h e a t o l l s o f t h e Nortiiuest Hawaiian Chain

( ~ d v a r d y 1961)2/. Both p l a c e s have undergone d r a s t i c changes d u r i n g t h e l a s t few y e a r s and however few o u r o b s e r v a t i o n s a r e , t h e i r documentation s h o u l d c o n t r i b u t e t o f u t u r e s t u d i e s of t h e i s l a n d s .

French T r i g a t e Shoal

Tern I + . l s n d o f Zrench Fri;ate 6 h o a l h z s been c c n v c r t e d t o an a i r - s t r i p , a~cl s p a r s e v e g e t a t i o n s o w s o n l y on ;,mzrgin o f a b o u t 50 ~ ~ l e t e r s width on t . e n o r t h and s o u t h s i d e s o f t h e a i r s t r i p , on l o o s e and 1 7 a r t i a l l y b a r e c o r a l sand ( S v i h l a , 1947; Larnoureux, 1961).

No s i g n o f any b i r d n e s t i n g a c t i v i t i e s was four-d on '?ern I s l a n d . Twelve Golden F l o v e r s ( P l u v i a l i s d o s i n i c a s s p . ) , 29 Buddy T u r n s t o n e s

(Arenaria.

I.

i i l t e r p r e s -and 1 S a n d e r l i n g ( C r o c e t h i a

alba

( p a l l . ) ) were t h e o n l y t r m s i e n t o r v i n t e r i n g r e s i d e n t s of t h e i s l a n d , t h e

p l o v e r s r u n n i n g on t h e a i r s t r i p , t h e o t h e r s on t h e mmgin o f t h e i s l a n d ( t h e a i r s t r i p eclbankment i s mostly s u p p o r t e d by c o r r u g a t e d i r o n break- w a t e r s ) . Only t h r e e i n d i v i d u a l s o f s e a b i r d s were i n t h e a i r around Tern I s l a n d , i . e . , a S o o t y Tern ( S t e r n a f u s c a t a 8loxam), a F a i r y 'Tern

(Gygis a l b a (~m.)) and a j u v e n i l e Red-footed Booby ( S u l a

--

s u l a r u b r i p e s Gould)

.

I t i s worth mentioning t h a t a d i s i n t e g r a t i n g c a r c a s s o f a h a t c h l i n g g r e e n s e a t u r t l e ( C h e l o n i a mydas

(L.))

w a s picked u p by one o f u s on t h e n o r t h margin o f t h e a i r s t r i p , i n l o o s e c o r a l s a n d , w i t h t h e c s r a p a c e crushed.

Kure A t o l l

The v e g e t a t i o n and t h e b i r d f a u n a of Kure toll have been d e s c r i b e d by Kenyon and Rice (1958) as l a t e as

1957.

Green I s l a n d was t h e n a p p r o x i - m a t e l y 1% m i l e s l o n g , and 1 m i l e wide, w i t h 10 t o 20 f o o t - h i g h dunes

behind t h e beach. It w a s a l m o s t wholly covered w i t h an Ifalmost impene- t r a b l e " t h i c k e t of S c a e v o l a bushes, e x c e p t one i n t e r i o r opening o f low h e r b a c e o u s v e g e t a t i o n .

U n i v e r s i t y o f B r i t i s h Colunbia, Vancouver, Canada.

Nuuseurn o f V e r t e b r a t e Zoology, a e r k e l e y

,

C a l i f o r n i a .

A g r a n t o f t h e N a t i o n a l Besearch Council of Canada, p a r t l y used on t h i s e x p e d i t i o n , i s g r a t e f u l l y aclatowledged.

I n December,

1959,

D r . Chandler Robbins, Jr. informed one of u s ( p e r s . corununication t o I4.d.F. ~ d v a r d ~ ) t h a t he had j u s t v i s i t e d Kure A t o l l , and t h a t a p r o j e c t had been s t a r t e d t h e r e by t h e U. S. Navy t o

"improvett Kure f o r t h e n e s t i n g of t h 2 two a l b a t r o s s s p e c i e s . The scheme was an atte!:ipt t o compe;lsa.te f o r t h e p o p u l z t i o n l o s s e s on t h e I i i d w ~ y i s l r m d s . Zlg-zag s t r i p s ( c f . F i g s . 2 and 4) were p l o w e d b u e o f t h e S c a e v n l z b ~ x h e s s o t h a t t h e s e b i r d s could f i n d more take-off a n d n e s t i n g

--.. -.-

p o s s i b i l i t i e s .

L i t t l e t r a c e of t h e s e changes could be d e t e c t e d on Green I s l L m d i n S e p t e n b e r

, 1961

; f o r s t i l l grc-2iter changes hzve s i n c e d r a s t i c a l l y a l t e r e d t h e v e g e t a t i o n . E a r l y i n

1961

an U.S. Coast Guard "Lorant' s t a t i o n was e s t a b l i s h e d t h e r e .

An estirnkted one t h i r d of t h e i s l m d - i t s whole narrower end-is t a k e n up by an a i r f i e l d . The a i r f i e l d ( ~ i ~ s . 1, 2) i s bordered by ScaevoLa of 2-3 m e t e r s h e i g h t and scjme Mes:::crsclmidia t r e e s . p a r t of

-..

. -

^{-.----. -.. ..-}

t h e s i j c t h e r n h a l f of t h e remainder consist:: ( ~ f h ; ~ . s e s , r o a d s , p l a y f i e l d arLd I . s ~ m s .

IP

t h e west c e n t e r of t h e i s l c d t h e r e i s a 625 f o o t h i g h a n t e r x a . Its system of p y - w i r e s r e a c h e s almost t o t h e beach 011 t h e North s i d e , and c o v z r s t h e c e n t r d f l a t and open p a r t of t h e remainder of t h e i s l a n d ( F i g s .

3,

4). The l a n d under t h e s e w i r e s i s c l e a r e d . Coherent, u n d i s t u r b e d v e g e t a t i o n o c c u r s on t h e beach c r e s t o f t h e s o u t h - w e s t , west and n o r t h w e s t s i d e of t h e i s l a n d , and a Scaevola s t r i p around t h e r e s t of i t . ,The west s i d e of t h e i n t e r i o r of t h e i s l a n d , where n o t plowed, c o n s i s t s of low S c a e v o l a and p a t c h e s of F z f r h a v i a , o r E r a g r o s t i s bunchgrass, w i t h one e x t e n s i v e g r a s s y a r e a (presun.:;-i~ly t h e " i n t e r i o r opening of low herbaceous v e g e t a t i o n " of Kenyon and Rice 1.c.). The f l o r a o f t h e i s l a n d is d e s c r i b e d by L m o w e u x (1961) of t h e same expedi- t i o r , ; . Clay (1961) shows two photographs of t h e i s l a n d .

A s b i r d h a b i t a t , t h e runway a n d t h e s e t t l e m e n t 2xe n s t u r a l l y ex- cluded. The i n t e r i o r had numerous n e s t i n g p a i r s of M~slced S o o b i e s ( ~ u l a d a c t y l a t r a Gould) and R e d - t a i l e d I r o p i c - B i r d s (Fhaethon r u b r i c a u d a

z a t h e w s ) )

,

b o t h s p e c i e s w i t h young r a g i n g from d o m y n e s t l i n g s t o

~ l r n o s t f l e d g e d young. The i n t e r i o r , and even t h e p r e v i o u s l y c l e a r e d a r e a , now l s r g e l y v e g e t a t e d w i t h Boerbavia, had numerous ( i . e . , many hundreds, but no e s t i m a t e was a t t a m p t e c i ) ~ s r r o w s i n h a b i t e d by idedge- t a i l e d S h e a r w a t e r s ( P ~ f f i n u s p a c i f i c u s L e s s o n ) , and by t h e Bonin I s l a n d P e t r e l s (Pterodroma hypoleuca S a l v i n ) t h a t d i d n o t y e t start t o n e s t b u t v i s i t e d t h e i s l a n d e v e r y evening. The S c a e v o l a t h i c k e t of t h e beach c r e s t had n e s t i n g R e d - t a i l e d T r o p i c - B i r d s , G r e a t F r i g a t e B i r d s ( I r e g a t a _{- - - - -} minor ~ r n e l i n ) and lied-footed Boobies, t h e l a t t e r e s p e c i a l l y on t h e t a l l e r

-

t r e e s of t h e s o u t h e a s t e r n dunes of t h e i s l a n d .

A

dozen o r s o B r i s t l e - t h i g h e d Curlews (Numenius t a h i t i e n s g Gmelin) were s e e n i n l o o s e groups on t h e beach, t o g e t h e r with ebout 35-40 Ruddy T u r n s t o n e s , a n d

6-10

TVandering T a L t l e r s ( H s t e r o s c e l u s incanuni (Gmelin) )

.

More curlews f e d on t h e open and low g r a s s y a r e a s of t h e i s l a n d i n t e r i o r , where t u r c s t o n e s o n l y r a r e l y were f l u s h e d . l o u r t e e n Golden F l o v e r s

mostly k e p t t o t h e runway and t h e open sand ijit a t t h e e a s t end o f t h e i s l a n d . . On t h e n o r t h e a s t of t h e i s l a n d 20-30 "Hawaiian Terns:' (blhite- cayped Noddy, Anous t e n u i r o s t r i s Guy) v e r e on S c a e v o l a bushes.

On September 1 2 , we v i s i t e d t h e l a r g e r of t h e t v o sand b a r s wliich a r e , b e s i d e s &Green Is l a n d , t h e o n l y v l s i b l e p a r t s of t h e z t o l l . On t h i s 400 meter-long sand b a r , p r s c t i c a l l y devoid o f v e g e t x t i o n , o n l y a dozen B r i s t l e - t h i g h e d Curlews m d a number o f Koddy ' i e r n s (Anous s t o l i d u s

(Stop.)),

common a l s o on ? e r n I s l a n d ' s beach l i n e , were seen.

We found 40 E a v a i i a n t/ionl< L e a l s (Monacllus s c h a u i n s l a n d i N a t s c h i e ) on t h i s sand b a r . The n o r t h and northeaste:-n s i d e o f T e r n I s l a n d seemed t o be a f a v o r i t e howling ground o f t h e s e a l s , and 25-30 s e a l s were count- e d t h e r e on t h e e a r l y a f t e r n o o n o f September 1 2 and

13.

The s e a l s s l e p t on t h e beach c r e s t , i n t h e shadow o f t h e t a l l S c a e v o l a bushes.

S e v e r a l of u s s y s t e m a t i c a l l y s e a r c h e d f o r d e a d , o r i n j u r e d b i r d s under t h e m y w i r e s . I n a s h o r t time t h e f o l l o w i n g were found:

F r i g a t e birds

.. - - - - - - ^{- -} - -

2 R e d - t a i l e d Tropic-Birds

- - - - - - - -

²

S o o t y Tern-

- - - - - - - - - -

¹

Gray-backed Tern ( S t e r n a l u n a t a P e a l e )

--

¹

$ l e d g e - t a i l ~ d S h e a r w a t e r s -

- - - - - - -

²

During o u r s t a y we w i t n e s s e d s e v e r a l such a c c i d e n t s . T i e t r o p i c - b i r d s a r e a p t t o h i t t h e w i r e s d u r i ~ g t h e i r mid-day aeriaJ. d i s p l a y s , and tlie

f r i g a t e b i r d s d u r i n g t h e i r con~munal soarirrgs. The s h e a r w a t e r s and p e t r e l s seem t o h i t t h e w i r e s a t n i g h t , - p a r t i a l l y b l i n d e d bg t h e e l e c t r i c l i g h t s on t h e b u i l d i n g s .

As a c o n c l u s i o n of o u r o b s e r v a t i o n s , h r e i s no y l a c e f o r t h e s o a r - i n g a l b a t r o s s e s now, e x c e p t p e r h a p s t h e beach, which could h a r b o u r a few b l a c k - f o o t e d a l b a t r o s s p a i r s . The gxy-wires w i l l i n a l l 1ii;elihood v e r y e f f e c t i v e l y keep them o f f . The o t h e r s e a b i r d s may s t a y , i f no f u r t h e r h a b i t a t is a l t e r e d , i n t h e way t h e y had l i v e d on t h e Midway i s l a n d s , w i t h

t h e e x t r a t o l l t a k e n on t h e i r p o p u l a t i o n s by t h e h a z a r d s o f l i v i n g n e a r and on human h a b i t a t i o n s .

R e f e r e n c e s

C l a y , I-Iorace F.

1961.

N a r r a t i v e r e l ~ o r t of b o t a n i c a l f i e l d work on Iiure I s l a n d

3

October 1355 t o

9

October 1959.

A t o l l Res. B u l l .

78.

pp.

7.

Kenyon, I(.';/. ,ad D.W. liice.

1955.

B i r d s o f ECure A t o l l , Eawaii.

Condor 50: 133-190.

Lamoureux, C h a r l e s H . 1961. B o t a n i c a l o b s e r v a t i c l n s on Leewsrd Hawaiian A t o l l s .

A t o l l Bes. B u l l .

79.

~ p . 7.

S v i h l a , Arthur. 1957. O b s e r v a t i o n s on French F r i g a t e S h o a l s , F e b r u a r y

1956

A t o l l Res. &dl.

51.

pp. 2.

Udvardy

,

^{ri.D.3'. 1961.} Tne ; i ~ , r o l d J. Coolidge Axpedition t o Laysan I s l a n d , 1961.

E l e p a i o 22 ( 6 ) : 43-47.

Legends t o f i g u r e s

F i g u r e 1. Loran s t a t i o n l i v i n g f a c i l i t i e s , f u e l o i l tanks, and rur.way, o o k i n

.

^The heavy, u n i n t e r r u p t e d S c a e v o l a t h i c k e t which o c c u p i e s t h e r i g h t c e n t e r , i s n e s t i n g ground of f r i g a t e b i r d s , masked b o o b i e s and r e d - t a i l e d t r o p i c - b i r d s . The hollow beach l i n e t o t h e ? . e f t o f t h e runway i s t h e f a v o r i t e hawling ground o f monk s e a l s . Green I s l a n d , Kure A t o l l , September

1961.

F i g u r e 2. P o r t i o n o f a i r s t r i p , Green I s l a n d , Lure A t o l l . Noto Loran tower ,guy w i r e s and r a d i a l b u l l d o z e r p a t h s . Zig-zag s t r i p s of s a n d , on t o p and l e f t c e n t e r , a r e t h e r e s u l t o f 1959 b u l l d o z i n g o p e r a t i o n s t o c r e a t e a l b a t r o s s runways. September

1961.

F i g u r e

3.

V e r t i c a l view from t o p of Loran t o w e r , SE s i d e , h e i g h t 625 f e e t . Kote changes i n v e g e t a t i o n due t o a c t i v i t i e s . Green I s l a n d , Kure A t o l l , September

1961.

F i g w e

4.

S E view o f v e g e t a t i o n clianges f r o i : ~ Loran tower. i i e i g h t

625 f e z t . Note guy w i r e s and narrow, r e c e n t b u l l d o z e r paths. S t r i p bulldozed i n 1359 shown from t o p t o bottom c e n t e r . Curlews u s e

i t

f o r f e e d i n g t o g e t h e r w i t h t h e g r a s s y p a t c h e s skown i n lower h a l f o f p i c t u r e . kiedge-tailed s h e a r w a t e r s and Bonin I s l a n d P e t r e l s a l s o burrow on t h e wide s t r i p . Green I s l a n d , Iiure A t o l l , September 1961.

A i l p h o t o s c o u r t e s y Foundation o f Environmental Biology.

F i g u r e 1

F i g u r e 2

F i g u r e 3

F i g u r e 4