sea turtles of bonaire

Sea Turtles of Bonaire

Research, Conservation & [email protected]. 717 2225 - 790 0433

What are sea turtles?

How many species are there? How many around Bonaire?

Where around Bonaire do the turtles live?

How do turtles live? What is their behavior?

How old can sea turtles become?

How can you tell the difference between male and female turtles?

Where do turtles nest on Bonaire? When is the breeding season?

How big is a turtle nest? How long until a nest hatches?

What proportion of hatchlings will survive?

What threats do sea turtles face?

What can I do to help?

What are sea turtles? Reptiles:

vertebrates

air breathing

have waterproof skin

lay eggs on land

What are sea turtles? Reptiles

Evolved from terrestrial turtle (tortoise)

Archelon ischyros, largest marine turtle, known to have lived 70 million years ago

Turtle species we see now have existed for about 20 million years

Archelon ischyros

Worldwide7 sea turtle species

Bonaire3 regularly seen species2 rarely seen species

Found elsewhere Kemps Ridley Flatback turtle HawksbillLoggerheadGreen turtleLeatherbackOlive Ridley

Green turtleTurtuga blankuChelonia mydasHawksbill turtleTurtuga karetEretmochelys imbricata

Where around Bonaire do the turtles live?Some survey and tagging program objectives:

make an accurate count of turtles by species locate the foraging habitats most used by turtles measure how fast individual turtles are growing determine how much turtles move around

Sea turtle general life history

Depth (m)Turtle diving behavior turtles living on reefs are active during day, mostly resting at night surfacing every 20-60 min depth range of juvenile hawksbills to 50 meters, adults to 200 meters leatherback turtles can dive to depths >1000 m

Sea turtle behaviors Feeding

Resting

Mating other behaviorsPhoto by Ellen MullerPhoto by Ellen Muller

Turtle migratory behavior where do turtles go after they are done laying nests on Bonaire?

two hawksbill turtles tracked in 2003 with satellite transmitters

two hawksbills, one green and one loggerhead tracked in 2004 with satellite transmitters

Satellite Tracking 2003 & 2004

Turtle Migratory BehaviorSatellite Tracking 2003 and 2004

Satellite Tracking 2005 Albert - male hawksbill fitted with transmitter 09 June Captured off Ebos ReefSponsored by the cruise ship Freewinds

Photo by Steve Jarrad

Satellite Tracking 2005 Happy - female loggerhead fitted with transmitter on 24 June at SW Corner Departed 29 June Arrived Vieques Passage 18 July Swam over 1100 km Sponsored by the Rotterdam Zoo

Sea turtle longevity Sea turtles are slow growing

15-30 years to maturity is typical

Adult turtles that we see may be 15-60 years old

For juvenile turtles you cannot tell males from females by looking at them

Only when adult do the males have long tails and claws on their front flippers

BONAIRE

KLEINBONAIREMain sea turtle nesting areasaround Bonaire Playa Benge Playa Chikitu Lagoen No NamePocket Beaches

Klein Bonaires No Name nesting beach

Hurricane Lenny damaged manyBonaire nesting beaches

Bonaire sea turtle nesting calendarPrimarybeaches

Chikitu W.P. Benge W.P.

No Name K.B.

No Name K.B. Pocket Beaches

Sea turtle nestcharacteristics

Green turtle: ~100 eggs per nest ~80 cm deep prefers open beach

Loggerhead: ~120 eggs per nest ~60 cm deep prefers base of dune

Hawksbill turtle: ~150 eggs per nest ~50 cm deep prefers under vegetation

Sea turtle nests hatch after about two months incubation

Turtles vulnerable to predation, especially when smallSurvival ratio example for stable population:

Hawksbill turtle female:lays 150 eggs per nest4 nests per seasonone season every 3 years12 year reproductive life (5 seasons) -> 3000 eggs produced during lifetime

successful hatch rate of about 75% -> 2250 hatchlings produced during lifetimeneeds to produce 2 replacement adults (1 female and 1 male) -> stable population survival ratio: 2250:2 = 1125:1

Fibropapillomatosis occurs in green turtles at Lac Bay and LagoenTurtles threatened by:

exploitation at sea (turtle meat, shell) exploitation on the nesting beach (eggs, turtle meat) habitat destruction (such as coastal development) disease (such as fibropapillomatosis) fisheries by-catch pollution (such as entanglement)

What you can do to help:

Dont pollute the sea

Keep vehicles off the beaches

Never buy sea turtle products, such as tortoise shell jewelry

Report any turtles in trouble around Bonaire to us immediately

Help out as a volunteer in our research, conservation and educational activities

Become a member or make a donation

Visit us at www.BonaireTurtles.orgSupport Bonaire www.SupportBonaire.org

Sea Turtles of Bonaire

Research, Conservation & [email protected]. 717 2225 - 790 0433Support Bonaire Inc. www.supportbonaire.org

sea turtles of bonaire

Documents

female turtles

sea turtles face

sea turtles of bonaireresearch

meters leatherback turtles

accurate count of turtles

fast individual turtles

turtle nest

nest hatches