ENVIRONMENTAL IMPACT RESEARCH PROGRAM

TECHNICAL REPORT EL-89-1O

SPECIESPROFILES:LIFEHISTORIESAND ENVIRONMENTALREQUIREMENTSOF COASTAL VERTEBRATESANDINVERTEBRATES PACIFICOCEANREGION

Report 1 GREEN TURTLE, Chelonia mydas

by Robert G. Forsyth, George H. Balazs Southwest Fisheries Center Honolulu Laboratory National Marine Fisheries Service National Oceanic and Atmospheric Administration

Hon o IuI , Hawai i 96822-2396

July 1989

Report 1 of a Series

Approved For Public Release; Distribution Unlimited Library NOAA, National Marine Fisheries Service SWFCHonolulu Laboratory F/SWC2 2570 Dole Street Honolulu, HI 96822-2396

Prepared for DEPARTMENT OF THE ARMY US Army Corps of Engineers Washington, DC 20314-1000 Monitored by Environmental Laboratory US Army Engineer Waterways Experiment Station P0 Box 631, Vicksburg, Mississippi 39181-0631 ______

Utrn1ag:H ff ci SECURITY CLASSIFICATION OF THIS P4 I Form Approved REPORT DOCUMENTATiON PAGE 0MBNo O7O4O788 Exp. Date Jun30. 7986 la. REPORT SECURITY CLASSIFICATION lb. RESTRICTIVEMARKINGS Unclassified 2a. SECURITY CLASSIFICATION AUTHORITY 3 DISTRIBUTION/AVAILABILITY OF REPORT Approved for public release; 2b. DECLASSIFICATION I DOWNGRADING SCHEDULE d stn but i on unl Imited.

4. PERFORMING ORGANIZATION REPORT NUMBER(S) 5. MONITORING ORGANIZATION REPORT NUMBER(S) Technical Report EL-89—1O

6a. NAME OF PERFORMING ORGANIZATiON 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION (If applicable) USAEWES See reverse. Environmental Laboratory 6c. ADDRESS (City, State, and ZIP Code) 7b. ADDRESS (City,State, and ZIP Code) See reverse. P0 Box 631 Vicksburg, MS 39181-0631

Ba. NAME OF FUNDING/SPONSORING 8b. OFFICE SYMBOL 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION (If applicable) US Army Corps of Engineers 8c. ADDRESS(City, State,andZlPCode) 10. SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK UNIT Washington, DC 20314-1000 ELEMENT NO. NO. NO. ACCESSION NO

11 . TITLE (lnclue Secyrity Classifiçaion) • . Profiles: Lite Histories and Environmental Requirements of Coastal Vertebrates and Invertebrates, Pacific Ocean Region; Report 1, Green Turtle, Chelonia mj’das

12J’ERSONAL AJTHOR(S) Forsyth, Robert G.; Balazs, George H. 13a TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (YearMonth,Day) 115.PAGE COUNT Report 1 of a series 1989 25 FROM TO July I 76. SUPLEMEJJTAY NOTAJION . . . . Avai aiie trom National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161.

17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP Environmental requirements Geographic range Ecological role Morphology

19. ABSTRACT (Continue on reverse if necessary and identity by block number) Species profiles are literature summaries of the , morphology, distribution, life history, and environmental requirements of aquatic species. They are designed to assist in environmental impact assessments. The green turtle, Chelonia ydas, is found throughout the Pacific Ocean region. Its status is listed as endangered by the Inter- national Union for Conservation of Nature and Natural Resources and as threatened in the U.S. Endangered Species Act and is included in Appendix 1 of the Convention on Interna tional Trade in Endangered Species of Wild Fauna and Flora. Females nest on a 2-, 3-, or 4-year cycle, laying one to six clutches per season and averaging between 100 and 110 eggs per clutch. Nesting normally takes place in the summer months. Hatching mortal- ity from predation in the marine environment is thought to be high. After an initial 3-year carnivorouspelagic stage, green turtles become primarily herbivores, residing in (Continued) iC(

20. DISTRIBUTION I AVAILABILITY OF ABSTRACT 2 1 . ABSTRACT SECURITY CLASSIFICATION UNCLASSIFIED/UNLIMITED D SAME AS RPT DTIC USERS Unclassified 22a. NAME OF RESPONSIBLE INDIVIDUAL 22b TELEPHONE (Include Area Code) 22c. OFFICE SYMBOL

OD FORM 1473, 84 MAR 83 APR edition may be used until exhaustea. SECURITY CLASSIFICATION OF THIS PAGE All other editions are obsolete. Unclassified Library $OAA, National Marine Fisheries Service SWFCHonolulu Laboratory F/SWC2 2?O Dole Street Horo1u1u, HI 96822-2396

of

The

the

to

PAGE

laws

THIS

man.

maturity

debris,

future

OP

appear

habitats,

the

than

sexual

marine

rates

conservation

other

Unclassified

reach

foraging

other

affecting

Growth

to

local or

and

of

SECURITYCLAS5IFICATION

predators

years

algae.

problems

few

25

beaches plastics

of

disregard

have Other

and/or

average

‘cs

nesting

the

and

AAOi

grass

Vs’1dA.j

of

and

‘1

ingestion

sea

(Continued).

jeopardy.

Turtles

the

on

JiuLof

in

£*flDLSK

long-lived

Laboratory

turtles

NOAA

2•sz2

alteration

slow.

feed

are

debris.

‘flL14k

they

ORGANIZATION

hunting Honolulu

, Service,

,

include

populations

i•’ieida1

in

turtles

generally

marine

where

fibropapillomas, SAGE

Center

are

of

turtle

green

THIS

with

PERFORMING

areas

Fisheries

op

and

(Continued).

equipment

96322-2396

OF

populations

many

Adult

diet

Fisheries

HI

NAME

Marine

incidence

coastal

modern

turtle

placed

with

ABSTRACT

c.

entanglement

C.*ulFICATtOw

of

Hawaii.

&

Unc1sjied

and

green

growing

have

in

use

19.

vary

shallow

Honolulu,

Southwest

National

6a

-‘- sgcuiry PREFACE

This report was published as part of the Environmental Impact Research Program (EIRP), sponsored by Headquarters, US Army Corps of Engineers (HQUSACE). Technical Monitors were Dr. John Bushman, Mr. David P. Buelow, and Mr. Dave Mathis of HQUSACE. Dr. Roger T. Saucier, Environmental Laboratory (EL), US Army Engineer Waterways Experiment Station (WES), was EIRP Program Manager. This report is designed to provide coastal managers, engineers, and bi ologists with a brief comprehensive sketch of the biological characteristics and environmental requirements of the green turtle, Chelonia mydas, and to describe how populations of the species in the Hawaiian waters may be expected to react to environmental changes caused by coastal development. The report has sections on taxonomy, life history, ecological role, environmental re quirements, growth, exploitation, and management. The report was prepared by Robert G. Forsyth and George H. Balazs of the Southwest Fisheries Center, Hon olulu Laboratory, National Marine Fisheries Service, under the support agree- ment WESCW88-188.

The authors gratefully acknowledge reviews by Messrs. Michael T. Lee, US Army Engineer District, Honolulu; Earl E. Possardt, US Fish and Wildlife Service; Richard E. Brock, University of Hawaii; and Ms. Karen Bjorndal, Uni versity of Florida.

Mr. Edward J. Pullen, Coastal Ecology Group, served as contract monitor for this study under the general supervision of Dr. C. J. Kirby, Chief, En- vironmental Resources Division, EL, WES, and Dr. John Harrison, Chief, EL, WES.

During the preparation of this profile, COLDwayne G. Lee, EN, was the Commander and Director of WES. Dr. Robert W. Whalin was Technical Director.

This report should be cited as follows:

Forsyth, Robert G., and Balazs, George H. 1989. ‘Species Profiles: Life Histories and Environmental Requirements of Coastal Vertebrates and Invertebrates, Pacific Ocean Region; Report 1, Green Turtle, Chelonia mydas,” Technical Report EL-89-1O, prepared by National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Honolulu, HI, for the US Army Engineer Waterways Experiment Station, Vicksburg, MS.

111

units

degrees

degrees

miles

thermal

tons

tons

kilometers

miles

meters

Obtain

feet

meters

miles

meters

tons

feet

meters

feet

igrams

imeters

To

1

ograms

ometers

ometers

1

1

1

kilocalories

Celsius

ki

metric

grams metric

liters

mil

cubic

cubic

hectares

square

square

nches ki

nches ki

centi meters

meters

mill

Fahrenheit

short British

pounds pounds

çunces

ounces

acre-

cubic

gallons

square

acres

square

nautical

statute

fathoms

i feet

I 32)

-

32

Metric

+

(°F

to

TABLE

Customary

2520

9072

00045

35

4536

02831

0929 4047

3048

54

iv

03527

00003527

0008110

2642

3861

5396

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03937

0.5556

0.

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3.785

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1.852 0.

1.609

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U.S.

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Customary

CONVERSION

U.S.

Metric

(Btu)

(°F)

(km2)

units

(°C)

(nmi)

(mi)

(m2)

mi2)

(kcal)

(m3) (m3)

(It2)

(t)

(t)

degrees

(ton)

(It3)

(cm)

(mm)

(mg)

(km)

(km)

(kg)

miles

thermal

(ha)

(gal)

miles

degrees

(lb)

(lb)

(oz)

(oz)

feet

miles

tons tons

(1)

kilometers

tons

(m) (m) feet

meters

(g)

meters

meters

feet

(It)

Multiply

Fahrenheit

short

British

pounds

pounds

ounces

ounces

acre-

cubic

gallons

acres

square

square

nautical

statute

fathoms

inches inches feet

kilocalories

Celsius

kilograms

metric

grams metric

liters

cubic milligrams

cubic

square hectares

square

kilometers

kilometers

centimeters meters

meters millimeters CONTENTS

Page

PREFACE iii CONVERSIONTABLE iv NOMENCLATURE/TAXONOMY 1 GEOGRAPHICRANGE 1 REASONFOR INCLUSIONIN SERIES 2 MORPHOLOGYANDIDENTIFICATIONAIDS 4 LIFE HISTORY 5 Mating 5 Reproductive Cycle 5 Nesting 5 Eggs 6 Hatchlings 6 Longevity 7 Basking 7 Migration and Navigation 8 GROWTHCHARACTERISTICS 8 FISHERY 10 ECOLOGICALROLE 11 Food 11 Behavior in Foraging Pastures 11 Predation 13 Eggs 13 Hatchlings 13 Juveniles, Subadults, and Adults 13 Parasites, Symbionts, and Diseases 13 ENVIRONMENTALREQUIREMENTS 14 Beaches 14 Internesting Habitat 14 Foraging Pastures 15 Pelagic 16 LITERATURECITED 17

V GREEN TURTLE, Chelonia mydas

NOMENCLATURE/TAXONOMY GEOGRAPHICRANGE

Scientific name . . . Chelonia mvdas Chelonia mydas can be found in (Linnaeus) 1758 all tropical and temperate seas Preferred common name Green between lat. 35°N and 35S and in turtle waters remaining above 20°C in the Other comon names . . . Hawali--Honu; coldest month of the year (King 1982). Tonga--Fonu, Fonu Tu’a’uli, Fonu Although the green turtle is a circum Tu’akula, Fonu Tu’apolata, Tual global species, it should not be Fonu; Society Islands--French: regarded as a single interbreeding Tortue, Tahitian: Honu; Guam--hagan, assemblage, but as discrete popula kame; Western Samoa--laumei; tions genetically isolated from each Tokelau--fonu; Fiji--vonu damu, vonu other (Groombridge 1982). ba, mako ba, ika damu Class Reptilia Order Testudinata Family Cheloniidae

1

in

in

it

on

in

for

the

are

the

Asia

some

Until

reli

1982),

Flora.

Endan

endan

so

impor

season.

Conven

Species

popula

protein

of

in

Surinam

turtle.

Natural

of

for

European

in

in

also

as

Union

and

(alive)

of

was

short-term

the

and

,

and

more

currently

the

parts

1986). part

.

populations

of

turtle

Trade

They

nesting

green

Pauna

in

for

are

1

listed

far stored

-

historically,

practices

turtle

Endangered

and

amounts

(Groombridge

settlement

the

Japan,

Nature

is

%4..

NWHI. Wild

1979).

are

stable

green

role

reservations

U.S.

of

International

of

green

easily

(Johannes

important

Pacific

and

large

Nesting

FFS,

for

Appendix

(IUCN).

the

They

listing

although

be

during

the

Italy,

an

the

the

major

ceremonial

1

the

number

in

International

Hemisphere

1.

in

a

times

by

Species

in

entered

(Pritchard

commercially;

and

on

Except

play

could

and

Island,

supplying

.4

(France,

have

Appendix

gered

listed tion

Resources

Conservation Act

tions gered

jeopardy.

ships

that Australia,

by

exploration

Western

played

tant

recently,

former

cultures,

also

gious

East

Painted

resighting Figure

-

r

2

of

are

of

in

in

of

New

of

are

the

They

and

the

many

Rose

for

the

off

Group

Manus

read- over-

there

Saudi

South

Ocean 1971);

Verde

Costa

Scilly

in

(Spring

reside

islands (Balazs

in

Frigate

on Some

through-

eggs

Guiana;

and

offshore for

Thailand

nestings

of

of

not

of

areas

important

the

sites

Australia

Island

been

coasts

numbers

islands

Cape

and

coasts

Northwestern

of

region.

Reef

an

2).

the

(Hirth

Islands

Islands;

SERIES

Phoenix

are

Cay,

their

Tanzania,

Africa,

not

1982);

Guinea

Most

Pacific

coast

is

French French

beaches

the

the

coast coast

(NWHI)

IN

source

large

in

nest

1983);

Europa

villagers

nesting

nesting and

Group,

1979).

the

New

Ocean

in

have

uninhabited

Samoa

coasts

several

which

and

and

American

and

(Figure

the

vast

1).

and

east

mid-Atlantic;

Society

in

3)

Pandora

food

have

as

and

Somalia,

Channel

Caribbean

include

especially

Fleay

on

Both

island

Galapagos

man

Papua

small

Caribbean

Gulf.

the

turtles

INCLUSION

Islands

Bunker

turtles

the

(Pritchard

the

in

the

South

Pacific

beaches

Island

by

worldwide

well

important

on

1975);

American

of

still

and

and

Guyana,

and

(Pritchard

d’Entrecasteaux

the

the

Island

in

(Figure

in

colony,

(Figure

FOR

and

Island,

Ocean

as

in

the

are

Green

the

turtles

Green

important

more

Major

Persian

accessible

Malaysia,

Mozambique

remote

nesting

out

an

coastal

REASON

1982c).

(Balazs

Island Hawaiian

Shoals

(Limpus Canton

1982a);

Caledonia

Atoll

District

Raine Capricorn

ily

the

exploited

or

today

region

islands, throughout

nestings

is

and

Mozambique.

nesting

Indian

the

the

Islands

Yemen;

Arabia

Ecuador; Rica; Surinam,

Pacific Ascension

Mexico; green 13

1 Lu I 9

MARSHALL 1 HELEFS REEF 9 BIKAR GUAM ISLANDS 8 2 MANUS DISTRICT 10 FUNAFUTI (5 SEPARATE NESTING SITES) 11 ROSE ATOLL PAIAU AP 3 BRAMBLE CAY I 12 VATOA 1UK 4 RAINE ISLAND; PANDORA CAY PONP 13 FRENQI FRIGATE SHOALS 5 BOUNTIFUL AND PISONIA ISLANDS 14 RAKAHANGA 6 CAPRICORN BUNKER GROUPS 15 PALMERSTON U- 7 D’ENTRECASTEAUX REEF 2. 16 SCILLY 8 UJELANG 17 RAROIA PAPtM %. A NEW SOWMON U GUNEA IC ISLANDS 14 C,) j3 11 WES ERN Iv)4 •SAI 15 16 L SEA ® : 7 0 12 FIJI SOCIETY 200_ ISLANDS

AUSTRALIA DALEDONIA

Important by r•ason of Iarg. population size. NEW ZEALAND ® €: Important by reason of isolation or uniqu. ecology. c Locally important. 400 tit I I I I 140° 160° 180° 160° 140°

Figure 2. Distribution of notable nesting sites of green turtles in the Pacific Ocean region.

a

a

by

or

in

as

in

the

the

4).

The

and

the

been

same

gray

four

of

with

scale

is

green

cm

green

during

hatch-

ending

chang of

smaller

olive,

radical

by

streaks

usually

by

elongate

not

carapace

plastron

carapace

plastron

and

variable

size

13

a pigmenta

black a

orange

typically

the

posthatch

pectoral,

Behind

these

coloration

variations

followed

of

in

is

has

reported

Free-ranging

until

hatchlings,

(Figure

side

consist

The

or

by

by

anal,

of

the

scutes.

same

and

away,

carapace

green, black

5.8-cm

observed

cm

in

Hawaiian

have

pair

this

variability

carapace

through

and

rear

been

hatchling,

radiating

followed

adult,

the

plastron

At

8

each

of

undergo

because

old)

the

to

a

old),

yellow

scutes

frontoparietal

go

pattern

with

scales.

to

old).

1986b).

of

been

humeral,

fades

of

an

scalation

the

brown,

to

On

the

of

preceded

not

black.

less

as

white

single

stage,

intensifies

postanal.

supraocular,

completely

7 it

to

As

mature.

pale

in

or

a

not

This

is

weeks

colors a

large

front

weeks

femoral,

has

a

weeks

head

inframarginal

however,

uncommon

gold,

a

black

(Balazs

This

pattern

plastral

turtles

is

and

(4

numbers.

presumably

diffused crown,

gular,

(2

to

intergular

single

hatchlings

have

a reach

buff,

from

of

pelagic

somewhat

(20

postocular

populations.

change

not

that

The

a

for

The

blue

Coloration

turtles

the

to

buff,

connected

is

scute

four

frontal

includes

frontal

prefrontals.

on

lings verified

their

changes;

less

turtles

length

lings disappearing

Thereafter,

pigment.

becomes

length

other

tion

color

is turtle

the

turning

pairs coloration

abdominal,

brown,

shows

background single paired

with

population.

ing turtle

even

It

in of

juveniles.

dark

4

)

5

is

is

is

this

ante-

long,

move-

green

Island

scutes, photo).

pattern

largest

head

ateral

scutes,

body

involves

an

carapace

turtles,

AIDS

Hawaiian

(postcen

are

scute,

(1

anteriorly forelimbs.

progression

the

carapace

The

East

in

its

the

scute

land

cover

Largest

of

is

the

of

withdrew

cm

efficient

in

Its

on

marine

marginal

and

includes

of costal

flippers

(central)

front

of

and

for

125

smooth;

view

water.

mode

supracaudal

NWHI.

of

kg.

carapace

turtle

IDENTIFICATION

colony

(precentral)

turtle

to

front

(see

and

small

the

sweeps

of

recently

pairs

water

the

230

AND

Aerial

up

The

normal

green

normal

pairs

11

hard-shelled

in

green

the vertebral

pair

and

nesting

scutes

3.

shaped

4

nuchal

streamlined

in

through

The

1

the

The

Japan

the

the

FF5

scutes, and

tral)

for nor

simultaneous

median with

both

and

relatively rounded.

heart very

length

ment

of

measuring

MORPHOLOGY

option.)

but

Islands.

Figure at turtle : season, and females do not copulate , :.. after laying their first clutch of eggs (Balazs 1980b). There is some uncertainty as to when fertilization actually takes place. Some researchers believe that fertilization is delayed until the following nesting season. This hypothesis raises the question of when the eggs of virgin females are fertilized, as well as the process by which spermatozoa would be stored for 2, 3, or at least 4 years between nestings. Most authorities now believe that fertilization is of the current season’s eggs. This would still require the short-term storage of spermatozoa because most green turtles Figure 4. Four-week-old Hawaiian green lay multiple clutches of eggs (Ehrhart turtle showing dark pigmentation phase 1982). of plastron.

Reproducti ye Cycl e supraocular is a temporal, and situ- ated behind the frontoparietal is a Adult females that remigrate to pair of parietals with an additional nesting beaches tend to do so on 2-, temporal on the outer margins of each 3-, or 4-year cycles or longer. How- parietal. ever, low recovery rates of remigrat ing females suggest that many females Sex is externally indeterminate may nest only once in their lifetime. before the onset of maturity. Females A 21-year study involving 12,000 are a minimum of 80—cm straight-line tagged females at Tortuguero showed carapace length at maturity; males are only a 16.4% remigration rate (Hughes slightly smaller. At or just before 1982). High tag loss may account for maturity, the tail of the male elon this low number, but high mortality gates and thickens at the base. The from fishing pressure and other tail of the male reaches a short impacts is certainly a possibility. distance beyond its hind flippers, whereas the female’s tail barely extends beyond the posterior end of Nesting the carapace. Nesting normally takes place throughout the summer months (seasons LIFE HISTORY reverse for the Southern and Northern Hemispheres) in the Pacific islands, with strong seasonal peaks that vary with location. Nesting occurs at Courtship and copulation take night on sandy beaches above the high place in shallow water in the general watermark. Once the female locates a vicinity of the nesting beaches. Most suitable area to deposit her eggs, she copulations occur early in the mating digs a body pit by using her fore- 5

I I

a

as

or

to

for

are the

The

al.

the

and

also

that

from

also

once

they

dif

when

from

joint

lower

high-

up

after

days,

higher

(Hirth

(NWHI)

showed

higher

et terres

cloaca

a

females

(greater

and

(Balazs surface.

days

clutches

8$

nightfall

free

of

usually

the

tended

a

eliminates

and,

hatch

7

fertilized

is

toward

sexual

nests

shorter

the

to

temperature

the

ratio;

for

diameter

high

(NWHI)

slightly

respectively.

surfaces

Island to

in

days

surface,

not

40

more

diurnal

break

54 whereas

later

eggs (Limpus

Also,

were

3

1982).

night

night,

change

to

If

the

hatchlings

sex

the

do

g, of

predators

to

to

temperatures

temperatures

wait

of a

affect

inhibiting

leave

East

in

is

the

sunset,

sand

at

at

surface

64.5

from

Island

eggs temperatures.

another.

varies

quickly

dig

the

50

the

takes

to

Average or

at

34°C.

eggs

and

yield

males,

result

Yntema

to

Even

of

hot

sand

the

near

they

the

to

East

size

and

and

marine

groups.

sand after

of

move

period

emerge

outside

exposure

and

eggs

ranges

of

shown

to

to

at

excavation

slightly

fertility lethal

hatchlings

Emerging

affect

24°

turtle

Egg

usually

mm mean

temperature,

Incubation

19$Ob).

two

bringing

when

and

1971).

eggs

for

activity

33°C)

be

ings

of

The

a

It

been

hours

lower

Sea

88.5%

44 can

or

that

population

the

eliminates

few beach. trial

could

and hatchlings exposure

oriented,

than encountered cease

one

(Mrosovsky effort

their

Chelonia

Movement

Hatchl

1983).

incubation

temperatures

incubated ferentiation. 2°C temperatures percentage

have

(Balazs

range

er

(Hirth Incubation

1980b). and

emergence that

decrease

are

one

with

weight

mucous

6

a

9

13

is

al.

are

are The

The

the

she the

mm

with

fol

same

col

Time

once

hind pit,

eggs

Ovi

her.

reach

NWHI,

of

return

ranges

et

actual

alter-

cavity

motion

from

nesting

30 facili

turtles

of

the

nesting.

and

but

the

turtle

spherical

olfactory

the

than

alternate

in

data

cavity

to

commences body

mean

the

110.

they

egg

time.

to

the

numbers

they

in

covered

by

hypothesis,

in

a

Owens

behind

Island

green

are

an

foreflippers,

with

20

hatchlings

islands.

of

recorded.

to

the

completed,

whole

more

and

the

number

clutches.

are

with

“social

sweeping

completion,

in

that

clutches

once

systems.

widely,

These

is the

after

this

with

return

that

East

encounter

the

eggs

sand

in

that

Island

100

been

fixity

flippers

so

1.8

On

The

“learn”

nest

takes

Once

front

eggs

In

egg

at

1971).

adults

Pacific

with

this

is

vary

time

strong

filled

in

beach

the

days,

termed

shows

East

have

flask-shaped

described

hind

site

they

1980b).

oviposition

lowers six

Most

fills

a

females exjsts

turtle

is

nesters

18

1979).

between

At

consistent

Then

Once

can

navigation

pit

females

other

(Hirth

the

her

in

as

normally

same

beach

imprinted

1980b).

to

have

nestings

a model.”

is

which

actions.

at

female

however,

strong

in.

Green

(Balazs

11

Research

out

Most

process

turtle

experienced

white.

other

throwing

the

chamber

many

using

18

season.

and

(1982)

and

first-time beach,

low

explanation,

tation

somehow

to

possibility

Remigrating

have nesting maturity

lected

from

single between

as generally

a

days

mean,

(Balazs

(Pritchard

leaving

nest.

flippers. the

egg

finished, average position

by

nating deposited

flippers and

to digs This a in for for and the East been

time “4 be 1926) limit bask- popu night place 1988). at (NWHI) in beaches turtles now breeding uncommon to has behavior, the the for Galapagos Kam groups al. common major out temperature overzealous longer (Whittow the of not cool takes green and et into turtles the is no Shoals haul appears observed body still thermoregulation, basking island 1980b; it escape - in ashore during may NWHI basking, is in green hypotheses in “bask” to basking been also but Forsyth all normally and relatively stay only for the of include Frigate and to NWHI. not on (Balazs radiation characteristic day, i in Basking Basking Basking current that they then 19$Ob; increase has years possibly 6). invested FFS, 1982). the 5. c: solar Basking and evening The chain an selected turtles French behavior time

- :rt not 4

:. : (Balazs (Figure ing is Islands for and at are from Balazs season, several lation. late bask behavioral the revealed the Chelonia during Observations Island, documented males. Figure 7 9 in of in is to and 5). has the al. Zug are the the old. been they habit aging esti being rela green feed- later Costa oldest Canada et period by of females (Balazs natural turtles captive Gulf out of Cape results in skeleto has maturity exceed the in to Oahu, are are growth caretta. two originally a 12 Zug were enter years (Figure aging until and contact the the behavior Two Islands, information only on late West coastal of areas by in The years sent have age 81 Early female all are work success Hawaii 19-year in using bask this Park about initiated and turtles 32 of Caretta males) This used vigorously and in in a skeletal to North 8 this rnydas. remote Tortuguero Life time, observations Galapagos turtles hatchlings where been was Hawaii. known juveniles nesting hatchlings turtles, of Australia, green 135 technique in after growth recoveries swim and apparent . at and in is over Sea few Chelonia. juveniles the (1985) In turtles, adults ashore documented the as has be this Estimates of green areas 1980b). that a Tag Once to green as aged slow of and with tagged marks as they long-lived. alive to At through 1 well In technique with Little Work NWHI. only 1956 Balazs turtles females coming grounds. Pacific, been the Carpentaria Basking of (1986), The Australia, (Balazs (4 loggerhead suggest for humeri 1983a). turtles suggests and chronological cyclic This in turtles. tively mated Rica, resighted Longevity still tagged made lifespan returned Hawaiian years, 1971). ing sea. lost reappear

water, hi,

in

at

no

to

of

of

and

but

not

this

can

when

from

wave

These

from

when

site

time,

this

guid

mini-

mdi-

1971).

sense,

turtle celes

pelagic

excess been

size

Basin;

Scilly

turtles

carapace

oceano

and does

Coriolis

straight-

longest raised

time

a

are a

currents.

of

cm.

Caledonia

this

in even

assumption

required

a

referred

at

from

a

of

immediately

during

turtles

unknown

have

emerges

and

composite

(Hirth 35

At

in

from

the

and

capture approximately

Islands

New

is

inertial

the

Pacific

a

day,

is

subtle

are

of

calculated

invertebrates

most

reach

of currents

reaches

Chelonia

in

a

are

there

cm.

1982b).

migrate

the

the

tagged

bicoordinate

this

with

turtles

as

it

5

to

prevailing

light-compass

captured

hypotheses

Generally

km factors

living

diet

in

sense,

straight-line

hatchlings

show

weighs

perception

at

hatchling small

Society

some

length

speeds

perhaps

distances

of

a

sense,

Since

the

40

is

are

made such

over

it “disappears”

be

recorded

Hawaiian

(Meylan

until

recovery

turtles

from

these

include

the

data

the

and

months

to

years,”

cues,

turtles

has

their

more.

long

tagged

current

to

km

of

cues

1982b).

just

CHARACTERISTICS

19

in

magnetic

sonar

The

20

or

arrival

calculations

carapace

that

eggs.

and

against

turtle

When

nest,

navigation,

turtles

turtle

The

Migratory

been

averages

“lost

return

cm

g

green

4,000

line

least

fish

captivity

assumed

period,

observations

environment.

as

the

“reappear”

35

length the

30

the

GROWTH

several

patterns,

ance,

force,

(Meylan

graphic

olfactory

tial

navigation

after

that

traveling

mum

These

Island tag travel going

of

cated

area. of

recoveries

have nevertheless,

8

to

of

of

for

al.

that

when

FFS,

with

modes

(Hirth

migra

tagged

behav Pacific

turtles

et

(Hirth

nesting

epizoic

foraging

available

of

and

conserva

even

shown

turtle

few

the

and

purpose

turtle

Island,

are

periodically

difficult

social

unknown

in

the

synthesis

from

have

Garnett

rates

energy

documented

it

East

routes,

predators

beaches

Australia.

green

sites

the

still

eliminating

foraging

in

Relatively

1982b).

principal

turtles

freeing

that

in

made

shows

migrate

are

recovery

or

Navigation

1980b).

turtles

seal.

7

recoveries

the

nesting

facilitating

nesting

Basking

migratory

Low

and

avoiding

green

have

will

be

1982b).

between (Meylan

Tag

monk

D,

behavior

aiding

to

believe

6.

ecdysis,

Balazs

of

and

Figure

Green may

*.

navigation

I.

(Balazs

tions

locally

“suitable11

1971). areas

turtles

of

establish

beaches. turtles

migrate

Migration

(1985)

basking

1971;

ior,

tion

algae, vitamin

aiding

ectoparasites

Figure

NWH Hawaiian - .

200 - ?::‘ JOHNSTON _ ATOLL , MARSHALL GUAM ISLANDS 4--

-— Y;LP I I!LP( • PALAU PONAPE

V

: ::::::: : , (0 44% • rt !rD 4b bVAN ATU , “1 ti ] LY %%,J/ CORAL —— .-.—z= NEW • ——. - SEA 4 —— —— • EDOA •::/ 200_ s’ :r _- — 4. CAPRIC RN %% AUSTRALIA I BUNK R , GRO S BRISBANE

ZEALAND

6O-- ;;;:

: tN-I 140° 160° 180° 160° 140°

Figure 7. Migrations of green turtles in the Pacific Ocean region, as shown by recaptures of tagged individuals. Arrows do not necessarily show routes of travel.

be

a

be

as

use

cm

the

the

the

easy

and

the

then

with

the

This

spear

nest-

when that

Fleay

areas

leads

their

large-

these

green

can

in

engines

growth

adults

matur

legally

growth

with

turtles

legally Johannes

in

of could

on

nesting

have

and

106.2

capturing

Bjorndal

and

listed

on

be

(Carr

different

of

assess

that Endangered

be

with

that

other

slow

to

of

of

islanders

beaches

areas

reach

They

green

to

are

at

deposit

believe

1980b).

data

turtles

throughout

taking

length,

before

1982b;

outboard

use

maturity,

and

people

harpooning

and still

detachable

(Limpus

the

80.8

of

with

to

restrictions.

to

decline

range

the

dependent

species.

cannot

other

areas

is

or

netting

the

can

that

methods

with

concluded

Pacific

nesting

growth

turtles

net,

diet

turtles

(Balazs

varies

some

is

and

turtles.

jurisdiction

Hawaii

habitat.

(Spring

and

carapace

maturing

this

under

ashore

at

size

most

reaching

rates

coupled

Australia,

cm

boats

the

Most

areas

fixed

In

allow

Hawaii

indigenous

(1988) mesh

the

with

green

importance

turtles

for green

Today,

In

include

subsistence

Act

are

In

hand,

green

92

a

different

The

to

come

of

U.S.

in

of

growth

by

fishery

after

researchers

by

in

Traditional

females

for

range,

of

will growth

The

1970).

Once

gathered

a

hunt

Bolten

access

1986).

ing

high-speed to

tip,

either

diameter

turtles

1983).

Pacific,

harvested

only

taken

Species taken.

Pacific,

threatened

Pacific.

under

as

FISHERY

sizes.

some

turtles

rates

straight-line

females

wide

ity, eggs. mean

females

are

Carr

rates

quality

and quality data

turtle

estimated

10

a

of

69

cm

of

by

in

8.7

the

much

but

fact

(the

and

were

were

that

from

1980)

were

long-

they

fish

years

long.

sites

sizes

study

forag

green

(81

end

growth take archi

growth

on

months.

nesting

All

(1982a)

foraging

a

range

28°25’N, (Bjorndal

the

Australia

they

and

pelleted

foraging

previously

of

recapture

cm,

area, study

juveniles 37

areas

47.9

Atoll

In

assume

rates

the

capillacea.

study

Walter

obtained in

turtles

other

by showed

of

District

would

to

turtle

towards

40

to

which

size

these

(lat.

19°08’N,

and

The

the is

in

where

Balazs

than

opposite

this

2

Kure

rates

to

maturity

and

squid,

made.

it

District

immature

at

at

to

Kau

Bahamas

seven

also

diet

turtles

in

by

at

Extrapolating

coastal

existence.

area

growth

full

the

area

of

backed

studies

Once

Atoll

Archipelago, Kau

a

(lat. from

35

rate not

though

the

estimates

rapid

a

rates

in

size

at

found

sexual Hawaii)

for

tendency

Limpus

frozen

Pterocladia study,

1982a).

of

in

from

environment.

the

same

fed

recapturing

1988),

Kure

tagged.

a

be

in turtle

Inagua,

are

area,

on

most

information

migrations

even

included

rates

These

ranged

Hawaii

to

this

the

reach

growth

fresh

1979;

appear

recaptured can

growth

size

and

from

undertaken

Hawaiian

1980b).

The

minimum

were

one

herbivorous

of

(Balazs

in

35-cm

in residency,

turtle

place

to

shows

varied

178°1O’W)

generally

Independent

a

to

Great

natural

recorded Bolten

a

areas

study

archipelago.

Growth

a

the

the

food,

growth

(Limpus slower

and

and

sites

intervals turtles

term that

ing found This

originally

long-range turtles

slowest

pelago).

is for

takes

Island

155°30’W) rates 35-cm

long. the

years

ranging

extensively This

in varied.

consistent

were

rates

within

turtles

of

their

tagging

(Balazs

start

begin

reach

turtles dry

cm

by

of

of

(3)

few

eat

are

the

are the

the

food

food

fish

tur

They

Com

their

35

a

would

Fish-

Cale

These

(South

matter

to

facing

direct

of

(Balazs

turtles

of

Pacific

discuss

jointly

on

of

and

harvest-

on

from

eggs

primarily

New

providing

1).

these

Fisheries

fishermen

turtles

sampling

(1)

that

analysis

to

sea

tube

turtles,

Captive

diet

Marine

the

Pacific digested

most

and,

a

by

(4)

few

(2)

are

people.

problems

reported

to

habitats

live

when

tropical

their

Pastures

dead

eat

a

Noumea,

populations approximately

experts

1980).

fed

1981).

spend

South

and

of

the

plastic

included 1978)

Information

the

Laboratory)

of

gathered

been

Australia,

and

in

National

(Southwest

will

regarding

in

only

the

island

obtained

turtles

Foraging

incompletely

turtle

the

length

have

turtles

but

preferred

Turtle

ROLE

(Fritts

by

protection jellyfish

recommendations

address

laws

normally

1986). (Limpus

in

pellets,

is

of

contents

flexible

in

islands for

contents

observations,

1979,

squid.

turtles

Commission

and States,

Honolulu

workshop

to

turtles

a

Service

eat

are

Green

eggs

Green

secure

a

In

their

make

of

fecal more

Palau,

1980a).

in or

Behavior

stomach

using

feeding stomach recovery

sources

and/or

fish

abundant ties

occasions,

herbivores

Food opportunistically(Table

ECOLOGICAL will

increased Pacific

and

recommendations

region

Pacific help

islands. and

United

(Johannes

held

Center marine

In eries donia,

ing

respected mission

11

a

In is

be

In

on

to

of be

by

it

is

to

has

and

the

the

the

how

and

and The

the

and

the

“off

num

with

many

Even

rope

wait

then

Older

prac

to

except

year.

by

future

1983b).

and

attach

eggs

collec

of

of

of

may

as

in

1982b).

guns

Atafu

the

impact

and tell

collected

notice

eggs.

depending

float turtle

gun,

caught

of

1982).

(Johannes

the

This the

Fakaofo

atolls

egg

retrieve

butt of

they

eggs,

traditional

to

economy11

compared

turtles.

advantages

and

are

spear caught

dwindling

of

areas of

also

allowed

(Balazs

impacting

for

Yap

still

spear

large

of

Spring

Pacific.

little

end

the

of

really

then

collected

of

clutch

whereas

beaches

a

coral

the

but

and the

are

a

in

subsistence.

are

are

Palau,

to

designated

the

population

nest

to

today

(Kowarsky

difficulty

the

being

some

up,

turtles,

times

“money

are

exist

inhabitants

of

have

of

combination

turtles

islands

other

1982;

tire,

In

When

with

taking

beginning

number

gear in

for

resurfaces.

a coastal

a eggs

overhunting.

of

the

to

rope

are each

dug

way

been

that

with

to

does

Nesting

people,

eggs

The

the

to

occurs

by

the

the

is

of

release

are

whenever

no

turtles

and

local

breakdown

scuba

float

certain

from

because

on

few

in

(McCoy

nesting

villages,

equipment

it

only

prey

turtle on

turtle

have

coupled

is

degree

populations

appears

gun.

they

also

a

Chelonia

turtles

at

turtles.

the

Most

use

of

inhabitants

the

concern

the

the

the

ban

attached

for removed

a

found,

indigenous

Nukunonu,

tion

exploitation

islands Tokelau

ber

Pacific. limits”

areas wild

by

Australia,

threatened

turtle

There

taboos many what

emergence

so, villagers modern

of gradual

1986). decline

on

coastal

the

tice

is shot, for

fish-stringer. once

spear

polypropylene take

reached only

They ii Table 1. Some important food sources recorded for green turtles in the Pacific Ocean region.

Locality Principal food source

Main Hawaiian Islands Pterocladia capillacea, Amansia glomerata, Acanthophora spicifera, Halophila hawaiiana, Codium edule, C. arabicum, C. phasmaticum, jy fasciata, j. reticulata, Ahnfeltia concinna Northwestern Hawaiian Islands Caulerpa racemosa, Codium arabicum, c. phasmaticum, C. edule, jy fasciata, Turbinaria ornata, Spyridia filamentosa Johnston Atoll Caulerpa racemosa, Bryopsis pennata, Halophila ovalis

Tonga Halodule ovalis, HaTophila sp., Syri ngodi urn i soeti fol i urn Tokelau Valonia aegagropila, Turbinaria ornata Fiji Halodule pinifolia, j. ovalis, Syringodi urn i soeti fol i urn

Kerrnadec Islands Pterocladia capillacea Tahiti Algae Palau Seagrass

Truk Seagrass and algae

Torres Strait, Australia Red and green algae

Papua NewGuinea Seagrass Southern Great Barrier Reef, Chlorodesrnis sp., Turbinaria sp., Australia Amansia sp., Enterornorpha sp., Polysiphonia sp., Champia sp., Dictyota sp., Zostera sp., Thalasia sp.

12

A

cm

in is

.

and

the

tur

Reef

main

land

her-

more

Most

known

juve

64

adult

Island

and

hatch-

sharks

Stomach

1980b).

turtles

stomachs

no the

predator

cuvieri,

Adults--

infested

to

However,

,

Intensive

are

predation

once

predation

difficult

and and

mongooses

months

piscicolid

green

fishes

and

the

in

hatchlings,

Thalassoma

East

Hermes

53

Diseases

and

bilunulatus; Carcharhinus

the

environment.

is

of

turtles.

tiger

five

take

and

the

shark

ignoblis

in

for

and

crabs

widespread

reef

and

it

that,

once

near

beaches

(Balazs

water,

branchiatus;

observed

on

of

captured.

for

1982).

hatching

turtles,

show

hatchling

burrowing

mortality.

Galeocerdo

1980b).

programs

marine

cats,

sharks,

and

most

the

wrasses,

found

Pearl

estimated

of

Bodianus

hatchlings.

Caranx

subadult,

Subadults,

were

probably

impact

checked

peak

the

muricata;

nesting

the

length

16

an

at

the

believe

however,

reef

green

high

species

commonly

conducted

the feral feeding

been

ectoparasites

Symbionts,

shark,

enter and

at

the

but

(Balazs

Islands

sharks

ulua,

(Stancyk

are

were on

groupers.

of

from Ozobranchus

accounted

gray

shark

during

evidence

most

enter

high; have

large

very 101 eradication

include

Known

rats,

5%

survey

Hatchlings--Ghost

tiger

13

found

no

juvenile,

Juveniles,

feed

crabs

carapace

small

large

assess

the

a

(NWHI) Parasites, ,

Stephanolepas

tles

in

of

niles

to

(NWHI) single ranging

is shark Other

regularly

In but Hawaiian

amblyrhynchos, of Chelonia

1974, and contents

was

purpureum

The

lings

melampvgus;

by to

hatchlings quite

researchers

have

hatchlings

predators

than

with

mit

13

m

2

in

to

to

to

to

al.

the

are

cues

eggs

free

with

have

surf

were

fre

sub-

50

pigs,

as

coral

Small

up

remote

extant

turtle

where

rapid

et

diving

turtles

in

surface

(Balazs bottom.

benthic

avoiding

of

and

effective

three

on

of

pastures,

and

present.

depending

are

beaches

much

rough

m

feral

ledges

most

the

turtles

conducive

20

waters pastures

in

3

restricted

olfactory

as

Balazs

deep

of most

single

to

are

relatively

locating

before turtles

sunlight, times

Resting

thereby

occurs

m

region.

taking

varies

are “sleep”

a

feeding

are

predation

preferred characteristics.

the

nesting

transmitters

are

than

10

mm.

using

areas,

However,

predation.

of

of

feeding

between

coastal

Feeding

mongooses,

15

where are

easily

Active

1980b;

preferences

by

bottom

only

spending

most

Ocean

that

nesting

than

returning

as

in

breaths

more undersides

to islands,

strategy

radio

surface,

turtles

at

currents.

nutrients

seagrasses

dogs

mammal

have

water

habitat

1982).

seagrasses

and

take

sec

amounts

less

Their

such

not

vicinity

protected

depths

1980b).

the

observed

and

(Balazs

deep

or before

in

turtle

to

probably

bottoms

growth.

living 30

small

and

yy--Nonhuman

Pacific

observed

Green

Feeding

h predators,

feral

on

the

strong

minimal

more

(Stancyk

uninhabited effective

is and nests

egg green

the

Predation

1987). mammals

2.5

found

sandy

of

recesses

often with

deep.

(Balazs

general

In

every

eight

been

usually

breath

mm

1980b).

on

Turtles

strate, normally quently

shallow

plant

adequate algae

Jives Algae

as

by

of

by

has

sea.

that

from high most

date,

walls

known

nega

define

moist

water

1984).

areas,

bright

hatch-

such

concen

numbers

between

turtles

a

females

variety

Coston

prevent

beaches.

is the

to

to

jetties,

Increased

crawling

developed

impact

by

are

be

season

the

sand

the

a

artificial

incidental

and

to

substantial in

as

Large

construction

but

have

requirements

to

small

inundated

by

on

may

from

Raymond

is

development

platform

from

1982;

retaining

have

occupied

nesting

beach

1982).

disasters

1982).

can

Females

excluding

such

not

and 1983),

important

nest cause

habitat.

breeding

away

accessibility

and

during

attention

discourage

1983;

enough

(3)

Nesting

that

beach

disoriented

a

activity

is

turtles

is

flooded

diffusion

turtle

to

can

habitat

a

Hoss

vulnerable It

harvesting,

Habitat

(Witham

REQUIREMENTS

and

or

lighting

easy

it

importance.

relatively

fine

Fleay

property

on

(Mortimer

access,

inland

mortality

of

gas

nesting

(Mortimer

activity

turtles

ecological

human

little

barriers

easily

(2)

within

slippage and

types.

in

beaches

its

seawalls,

(1)

them

and

deterrent.

which

or

and

of

that

appear

tides

nest

are

front

below,

Study

nesting

prime

impact

limit

Human

spills.

Green

sea,

reproductive

shun

beach

the

oil

catch,

Internesting commercial

trated

received of

nestings despite making

(Limpus

from

areas

levels

from

Physical

may

hopelessly groins,

unnatural

lings lights

lighting

Clements

to

obvious

beach

tive

Artificial

of

include facilitates enough excessive

spring

table

enough

the

Beaches of

ENVIRONMENTAL

14

as

et

the

all the

can

and

The

the

and

high

also

that

ova,

mci-

been

neck,

small

green

solar

still

being

in

barna

in

in

marine

results

include

signif

remora,

Recovery

of

Hawaiian

turtles,

feeding.

obstruc

diameter

survival

They

has

fibropap

the give

neoplasm.

of

Hyachelfa

is

from

are

of

parasites,

have

the

almost

in

disorienta

by stress,

the

of

1986a).

to

the

and

to

and

be

identified

cm

green

in

causes

(Glazebrook

size

Turtle

turtles

and

which

of

increase

around

trematode

pollutants

1987).

eyes.

physical

30

number

excessive

1980b).

Team

testudinata

in

cause

include

well

ultimately

Sea

vision,

growths

system, An

to

(Balazs

fnternal

amphfpod,

(tumors)

that

and

and

hirudin

investigation

green

swimming

found

growths

1986,

and

may

turtle

Florida

fibropapillomas

well-being

members

of range

masses

possible

(Ealazs

the

growing death

of

chemical

Spfrorchfdae,

in

Recovery

immune

these

from

the of

Hawaii

hexastylos;

tail,

reduced

viruses,

predisposition

the

population,

Blair

These

Symbfonts

a

but to

huge

normal

(Hawaiian

1986a).

sp.

usually

response

in

believed

impact,

in

of

of

the

Chelonibia

to

number

blindness,

to

growths seen

on

to

1989).

Neoplastic prompted

Turtle

are

talitroidean is

1981;

A

genetic

illomas

(Balazs Team

priority

dence,

incidence has

Sea

been

It instances,

Hawaiian

flippers, tion

tion,

result

impair and

a

immune

secretion These

radiation,

, warts

unknown,

seen

fibropapillomas cause

icance turtles

al.

identified status

Pacific.

Echenefs especially

Platylepas

des,

tortugae. the food sources and resting habitat are available. The nearshore benthic habitat surrounding the main Hawaiian Islands is limited by dramatic drop- offs usually within a few kilometers of the shore. Algae, the main food source in Hawaii, is found in the nearshore waters where sunlight and proper substrate are conducive to growth. Freshwater seepage stimulates algal growth in many areas, which are often popular feeding spots. Most habitat is hard-bottom surface or coral rubble that is required by their major food sources for proper attach- ment. One important turtle foraging area, however, on the south coast of Figure 8. Adult green turtle with radio Molokai has extensive mud flats where transmitter attached to carapace (see seagrass, Halophila hawaiiana, is Dizon and Balazs 1982). Trig Island, present (Balazs et al. 1987). FF5, NWHI. At Johnston Island, a remote these internesting areas and give them atoll located south of the main Hawai appropriate protection (Meylan 1982a). ian islands, green turtles use two feeding areas that exist side by side. Radio tracking of eight green On the south shore is a large field of turtles (four males, four females) at Caulerpa that extends 100 m. Slightly French Frigate Shoals (NWHI) during seaward, in deeper water, Bryopsis is the breeding season showed strong site present on the tops of coral heads. fixity for males and females alike Both areas will normally have several (Figure 8). All eight turtles stayed foraging turtles that can easily be in proximity of the nesting islands monitored from a nearby peninsula. where transmitters were attached, even Johnston Island is of special ecolog though another important nesting ical interest with regard to environ- island was only 9 km away (Dizon and mental contamination because of its Ealazs 1982). use as a storage area for nerve gas, mustard gas, and dioxin. High altitude nuclear testing also took place here Foraging Pastures in 1958 and 1962 (Balazs 1985b; Balazs and Forsyth 1986). Green turtles are unique among sea turtles in being primarily herbi Resting habitat is found in prox vores. They are mainly associated imity to foraging areas, usually with seagrass pastures or areas within 2 km or less. Large turtles abundant in desirable marine algae prefer small caves or protective out- (Hirth 1971). Research in Hawaii on croppings often associated with sub- feeding and resting habitats is the marine cliffs. These usually have most thorough to date in the Pacific fine-grained sand or powdery silt islands. Green turtles in Hawaii can bottoms that the turtles rest on. In be found wherever adequate accessible Hawaii, these sites are found along an 15

L

a

in

of

The

the

I

has

_ from

has

from been

with

ani

(Carr

by

mdi-

major

con-

plas

being

,

Balazs

amount

by

eating

pelagic

turtles

a

problem.

Sciences

of

dead

has

extent

was

canal

to

by

are

accumulated

be

the

and

of

turtles

used

marine up

debris.

problem

entangled

and

is

survival

sea

may

environment

which pollution,

amounts

prone

debris

During

other

entanglement

on

Academy washing .5 turtles

seabirds

alimentary debris

turtle are

ever-increasing

affecting

aesthetic

and

environmental

çs

becoming large

documented

debris .

marine

ocean

from the

• convergences

impact

%*SS. an

debris, The

composition marine

press).

of

sea or S

this

t-js:.

of

turtles

f/I*. on

‘f$S

or

the

young National

.

which

in

major

The

scraps

to to the

4& same

only

debris, of

-

‘4 a marine especially

.5

41r U.S.

into

Marine dumping

.

the debris. S

S. -;;::. . ‘.

. (1985a).

ingesting

synthetic extensively 1987).

threat impaction

cates plastics

number in

plastic turtles

(Shomura

of exposed period, mals,

changed

marine tic

1973 become The

sidered workshop

16

or

be

of the

This

same the

and

the

than

origi

macro-

rnigra

epipe

in

can

conver

at

protect

feasible

swirnrning

currents

believed

The

rnuch estimates

advection

as

the

the

1987).

on.

waves longer

than

of

within

convergences

by

draw

in now

rnust crevices,

more

shore

1980b).

turtles around

years feed

(Carr

last

in

turtles

current

to

making

are

encounter

large

draw

that

These

longer

areas

borders

and

supposed.

created

turtles

channels

they

with

is

first

(Balazs

years

in

Smaller

Young

also

heads,

closer

from

3

are

drop-off

These

forces

thought,

often

of

that

young

their

stage

eventually

coral

that

27-rn

thought,

of

turtles

currents

more

dwellers

originally

resting

Posthatchlings

flat.

of

eddies. downwelling.

turtles

to excess

coastline. spend in

nally

pelagic

plankton

advection

young than

tions

originally

and occur seaward

gences

and

lagic

to

Pelagic

strong

the

reef vertical-walled base

found 18- the in

Ir

and

the

eds.

NOAA

ocean

1986.

Lab., Fish.

Hono

Atoll. Turtle

on

debris,

ecology

turtles

pp.

Tokelau.

turtles.

of

Entangle-

Honolulu,

387-429

22

and turtles in

Mar.

assessment.

NOAA,

pigmentation Ontogenetic

Yoshida,

green

Honolulu marine

marine

Commer.,

Johnston

Forsyth.

Southwest Sea

workshop

Pages

Impact

1985

of

1924,

usage

NOAA-TM-NMFS-SWFC at Fibropapillomas Status

of

turtles:

H-86-9,

H.O.

Serv.,

279:1-29.

285:1-46.

the R.G.

Cent.

Dep.

turtles.

1986b. plastron

and

20:280-282. Hawaiian

Rep.

1983b.

of

1985a.

Atoll:

NMFS,

and

Fish.

Bull.

1985b. 1986a.

Bull.

the

ecology

marine

impact

turtles

Fish.

U.S.

ingestion.

green

96822-2396.

G.H. in

November

in

39:1-3. and

G.H.

traditional

G.H.

Res.

Res. Memo. G.H. G.H. Mar.

G.H.,

HI and Admin.

Shomura

and

Johnston

hatchling marine Herpetol.

their Proceedings R.S. fate Atoll debris 26-29 54. ment Hawaii. Tech. of Hawaiian Newsl. Atoll of changes at Status J. Southwest lulu, Natl. Cent.

CITED

Balazs, Balazs,

Balazs,

Balazs, Balazs,

Balazs,

17

A

in

of

of

and

sea

ed.

the

Sea

Dep.

Res.

Fish.

LITERATURE

NMFS,

turtle

mydas.

Aquar

Press,

of

117-125

methods turtles of

in

Pacific

rates

Pacific.

Turtles.

U.S.

turtles components

pp.

Biology Atoll turtles:

Comm.

Synopsis

Institution

green.

Memo.

the

Pages

Bjorndal,

Field

Status

141 Sea

(Waikiki

Growth

Sea

Chelonia

the

Hawaiian

of

Marine

ed.

turtles

Pac.

central

dietary

ands.

K.A.

i’a

Islands.

on

Tech.

of

11:5-6.

Institution

1980b.

Isi

jn

Conservation

D.C.

1980a.

the

1982c.

the

1982a. 1982b.

1975.

1983a.

39:1-3.

South

Kilo

data

green

Smithsonian

turtles, NOAA

Rev.

in

and

Archipelago.

Bjorndal,

resource

Hawaiian

232:22-24.

D.C.

Wash.,

G.H.

G.H.

G.H.

G.H.

243-252

184:1-7.

G.H.

G.H.

G.H.

Phoenix

sampling

Newsl.)

green

K.A.

Canada.

the

islands. immature in

shared in Bull. for Pages ium Biology Press, the biological Newsl. of Smithsonian turtles Herpetol. Commer., Hawaiian Conservation NOAA-TM-NMFS-SWFC-7, Wash., Turtles.

i_fl

Balazs, Balazs, Balazs, Balazs, Balazs, Balazs,

Balazs,

a

J.

FAO

of

N.

for

and

j

data

in IUCN

Nat.

tre

sea

Team.

Con- 1982.

turtle

green

1988.

Reef, Tech.

green

biolog

and

Gerro

D.C.

changes

of 7:4-5.

plan feeding eastern

red

1758.

and

29-38

of

pp. mvdas.

Smithson- by

T.

Nat.

and

NOM

Carpentaria.

the

95

Campbell,

green

turtle.

Hermes

19.

Wash.,

Newsl.

review

Recovery

Pages

of

Pelagic

Observations in

Crowley,

seal

recovery

A

Biology

Spirorchidae)

Synopsis

and

Alcorn, the

Chelonia

Gilmartin.

Turtles. cardiovascular M.

(compiler).

Commer.,

(Linnaeus)

Pathological

R.S.F.

Green

Gulf

Press,

Conserv.

Turtle 151-180.

85:1-8,

ed. emergence

monk

turtles.

on draft

NOM-TM-NMFS-SWFC-107,

G.

Turtle B.

D.J. 1981.

Sea

1982. 1.

91:361-368.

1985.

W.G. Dep.

with the

turtles

1971.

Pearl

pp.

turtle 1981.

mydas J.S.,

sea

Amphibia-Reptilia

Mar.

of

Sea

(Digenea: in

Union Final

art

of data

on Synop.

1985:262-264.

S.J.,

and

R.G., NMFS,

U.S.

Path.

sea

L.M.

reproduction.

H.F.

T.H.

IUCN

Hawaiian Bjorndal,

Institution

Blair.

pp.

Fish. ical

Chelonia 1989.

Hawaiian tInt.

Resour.),

book,

The

Comp.

green associated

matodes

D.

Copeia turtles

non-nesting

Goudberg.

Pacific.

habits

1986. 24

Memo. turtle

The ian

dette, servation

K.A.

turtle

Hirth,

Hawaiian

Groombridge,

Glazebrook,

Garnett,

Fritts,

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Ehrhart,

18

a

-

sea

the

on

and

the

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sub-

in

Hoss.

Biol.

Corn- 1970.

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35:75-92.

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NOM-TM-SEFC

NMFS,

southeastern

by

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Dep.

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sea

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Aust.

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A.B.

and

marine

breeding

pp.

of Zool.

revision

of

the

U.S. 18(6B):352-356.

alteration their of

(Platyhelminthes:

of

the

remigration

in

U.S.

NMFS,

44(5):13-20.

turtles

Memo.

A

G.H.

in

J.

M.H.

1988:555-564.

107 and L.,

Forsyth,

rates

revision

Chelonia on

in

their

nesting and

A

Impact Bull.

and

Preliminary

Rev.

Digenea:

Memo.

and

habitat utilization

R.G. Aust.

Tech.

Chelonia).

outlook

at

around

Microscaphidiinae

marine

Microscaphidiidae)

1986.

2:282-284.

Copeia

Synopsis

K.A.,

pp.

pastures.

grounds

States.

telemetry 1987.

debris

of

Growth

1987.

Octangiinae turtle

Fish. A.E., in

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turtles

turtles,

57

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NOM

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Pollut.

G.H.,

0.

D.

A.

habitat

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United turtles

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green

survival

Mar. marine

sitic Chelonia).

Digenea:

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34:241-277.

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Bahamas. feeding

1988. Dizon,

green

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Bjorndal, Balazs, Hughes, G.R. 1982. Nesting cycles in Limpus, C.J., and A. Fleay. 1983. sea turtles--typical or atypical? Management and turtles. Pages 535- Pages 81-89 jjj K.A. Bjorndal, ed. 540 jn J.T. Baker, R.M. Carter, P.W. Biology and conservation of sea Sammarco, and K.P. Stark, eds. Pro- turtles. Smithsonian Institution ceedings: Inaugural Great Barrier Press, Wash., D.C. Reef Conference, Townsville, August 28-September 2, 1983. JCU Press. Johannes, R.E. 1986. A review of information on the subsistence use Limpus, C.J., P. Reed, and J.D. of green and hawksbill sea turtles Miller. 1983. Islands and turtles. on islands under United States The influence of choice of nesting jurisdiction in the western Pacific beach on sex ratio. Pages 397-402 Ocean. Southwest Region, Natl. Mar. i_fl J.T. Baker, R.M. Carter, P.W. Fish. Serv., NOAA,Terminal Is., CA Sammarco, and K.P. Stark, eds. Pro- 90731-7415. Southwest Region Admin. ceedings: Inaugural Great Barrier Rep. SWR-86-2, 41 pp. Reef Conference, Townsville, August 28-September 2, 1983. JCU Press. Kam, A.K.H. 1986. The green turtle, Chelonia mydas, at Laysan Island, Limpus, C.J., and D.G. Walter. 1980. Lisianski Island, and Pearl and The growth of immature green turtles Hermes Reef, summer 1982. U.S. Dep. (Chelonia mydas) under natural con- Commer., NOAA Tech. Memo. NMFS, ditions. Herpetologica 36: 162-165. NOAA-TM-NMFS-SWFC-107,24 pp. McCoy, M.A. 1982. Subsistence hunting King, F.W. 1982. Historical review of turtles in the western Pacific: of the decline of the green turtle The Caroline Islands. Pages 275-280 and the hawksbill. Pages 183-188 j i_fl K.A. Bjorndal, ed. Biology and K.A. Bjorndal, ed. Biology and Con- Conservation of Sea turtles. Smith- servation of Sea Turtles. Smithson- sonian Institution Press, Wash., ian Institution Press, Wash., D.C. D.C. Kowarsky, J. 1982. Subsistence Meylan, A. 1982a. Behavioral ecology hunting of sea turtles in Australia. of the west Caribbean green turtle Pages 305-313 K.A. Bjorndal, ed. (Chelonia mydas) in the internesting Biology and Conservationj of Sea habitat. Pages 67-80 j K.A. Bjorn Turtles. Smithsonian Institution dal, ed. Biology and Conservation Press, Wash., D.C. of Sea Turtles. Smithsonian Insti tution Press, Wash., D.C. Limpus, C. 1978. The reef. Pages 187- 222 jn H.J. Lavery, ed. Exploration Meylan, A. 1982b. Sea turtle migra North, Australia’s Wildlife from tion--evidence from tag returns. Desert to Reef. Richmond Hill Press, Pages 91-100 K.A. Bjorndal, ed. Victoria, Australia. Biology and jConservation of Sea Turtles. Smithsonian Institution Limpus, C. 1979. Notes on growth Press, Wash., D.C. rates of wild turtles. Mar. Turtle Newsl. 10:3-5.

19

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on

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marks New

con- 1985.

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turtle Insti

Bjorn

preda

Bjorn

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Caretta

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36:129-

Contrib.

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C. 519-522

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Papua

K.A. K.A.

K.A. Sci.

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Conservation

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Wash.,

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in

age

Balazs.

turtles.

and

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j

Balazs.

in

jj

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D.C.

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D.C.

the

Biology

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Pac. Non-human

determination Smithson.

and Pages

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33:9-10.

Age

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291-295

Sea

139-152

Wash., 281-289

incremental and

1982.

turtles

34

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1982.

1982b. and

Biology of

1982a.

mydas).

by

A.H.

habitat Biology

sea

behavior skeleton.

1986.

Newsi.

Pages

populations Turtles.

Pages S.E. influence.

R. 427, Pages

G.C.,

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Turtles.

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G.R.,

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Turtles.

G.R.,

of

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Sea

in Zool.

caretta, loggerhead

chel.

for Turtle

Skeletochronological

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