Migration Routes Of Atlantic Loggerhead Turtles

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Transcript of Migration Routes Of Atlantic Loggerhead Turtles

Atlantic Sea Turtles

Green Turtle(Chelonia mydas)

Leatherback (Dermochelys coriacea)

Hawksbill (Eretmochelys imbricata)

Olive Ridley (Lepidochelys olivacea),

Loggerhead (Caretta caretta)

Kemp's Ridley(Lepidochelys kempii)

Threats

• Coastal Development

• Illegal poaching of turtles and eggs

• Fibropapilloma Tumors

• Pollution and pathogens

• Global warming

• Boats

• Beach fortification

Nesting threats

• Increased Human Presence• Beach fortification

–cleaning, armouring and replenishment • Coastal Development• Illegal poaching of turtles and eggs• Artificial Lighting • Predation

Marine Environment Threats

• Fisheries

• Ingestion of Marine Debris

• Oil and Gas Exploration

• Boats

Fisheries

Cause n %Entanglement 23 24.73

Trauma 22 23.66

Hooks + monofilament lines

18 19.35

Crude oil 2 2.15

Spontaneous diseases 5 26.88Unknown 3 3.23

Autopsy results on 93 turtles washed ashore in the canaries

Mating

Mating facts• Mating Season March-October depending on the

species

• Gestation is between 6-10 weeks

• Clutch size varies between 70-190 eggs depending on the species.

• When the young hatch out of their eggs, they look for the light of the moon to guide them towards the sea.

Temperature-dependent Sex Determination, or TSD

• Lower temperatures tend to produce males, while higher temperatures tend to produce females

• Remember *Hot chicks – cool dude`s!

Migration routes of Atlantic

Loggerhead Turtles

Migration Route

Canary Islands

Navigation cuesEvidence suggests hatchlings sequentially use three

different sets of cues to maintain orientation;

1. While on the beach, hatchlings find the ocean by crawling towards the moon heading for the lower, brighter seaward horizon

2. Upon entering the ocean, turtles initially orient seawards by swimming into waves, which can be detected as orbital movements from under water.

3. Set a magnetic course based on near shore cues. Sea turtles may use the earth's magnetic field not only as a cue for compass orientation but also as a source of world-wide positional information.

Their journey• Loggerheads travel around the large ocean

currents in a wide loop.

• From nesting beaches in Florida, they follow the Gulf Stream across the Atlantic to Madeira, and then head south to the Canary Islands and Cape Verde Isles, before heading back to the south-east coast of the US.

Legal Status/Protection

• All sea turtles are included in Appendix I of CITES), therefore cannot be traded commercially

• Six out of seven sea turtle species are protected by the Endangered Species Act

• It is estimated 1 in 1000 hatchlings survive to maturity.

Yes, I said YOU!

You can help

Volunteer Projects• Global Vision International – Protection and conservation

project based in Greece

• Volunteers will engage in daily morning surveys to record nesting activity and protect turtle nests against predation by mammals and inundation by sea water . Volunteers will also provide conservation information to overseas visitors and the local community. – http://www.gvi.co.uk/projects/Europe/Greece/volunteer-turtle-con

servation-project-greece/home?gclid=CKLy-dDc3JkCFRMhnAodUTGGWA

Sea turtle conservation in Costa Rica

Aims

1. Identify the size and status of the nesting leatherback turtle population

2. Protect nesting turtles and their nests from poachers and predators

3. Improve understanding of leatherback biology through quality scientific research

• http://www.i-to-i.com/volunteer-projects/marine-and-turtle-conservation-in-costa-rica.html

Sea turtle conservation in Cyprus

A group of professional scientists and student volunteers dedicated to undertaking fundamental and applied research on marine turtles whilst supporting local capacity building and environmental awareness efforts necessary for successful conservation.

• http://www.seaturtle.org/mtrg/

For additional species information

• http://www.cccturtle.org/

• http://www.seaturtlestatus.org/

• http://www.seaworld.org/animal-info/info-books/sea-turtle/index.htm