Turtles

General Information

North Sea

Baltic Sea

Clyde Marine Region

Adriatic Sea

Eastern Mediterranean Sea

Turtles

Layer Info
Category	Ecology
Sub-category	Other

Description

Sea turtles are large marine reptiles, air-breathing reptiles that inhabit tropical and subtropical seas throughout the world. Their shells consist of an upper part (carapace) and a lower section (plastron). They have many different sizes, shapes and colors, but all have large flippers and are well-adapted to life in the ocean (NOAA, n.d., Sea turtle conservancy, 2024). The olive ridley is usually less than 100 pounds, while the leatherback typically ranges from 650 to 1,300 pounds! The upper shell, or carapace, of each sea turtle species ranges in length, color, shape and arrangement of scales (Sea turtle conservancy, 2024).

Altough marine turtles have existed for at least 150 million years old (Sea turtle conservancy, 2024), most scientist recognise only seven marine turtle species all classified as vulnerable or at risk (some higher risk than others):

• Green - Endangered in the United States under the Endangered Species Act + Endangered (facing a very high risk of extinction in the wild in the near future) by the International Union for Conservation of Nature and Natural Resources (IUCN)
• Leatherback - Endangered in the United States under the Endangered Species Act + Vulnerable (facing a high risk of extinction in the wild in the immediate future) by the International Union for Conservation of Nature and Natural Resources (IUCN)
• Hawksbill - Endangered in the United States under the Endangered Species Act
• Loggerhead - Threatened in the United States under the Endangered Species Act + Endangered (facing a very high risk of extinction in the wild in the near future) by the International Union for Conservation of Nature and Natural Resources (IUCN)
• Olive ridley - Threatened in the United States under the Endangered Species Act + Endangered (facing a very high risk of extinction in the wild in the near future) by the International Union for Conservation of Nature and Natural Resources (IUCN)
• While hawksbill - Critically Endangered (facing an extremely high risk of extinction in the wild in the immediate future) by the International Union for Conservation of Nature and Natural Resources (IUCN)
• Kemp’s ridley - Critically Endangered (facing an extremely high risk of extinction in the wild in the immediate future) by the International Union for Conservation of Nature and Natural Resources (IUCN)

Threats: Sea turtles face significant threats around the world including (Sea turtle conservancy, 2024):

• Bycatch in commercial and recreational fisheries
• Loss and degradation of nesting and foraging habitats due to coastal development, pollution, and climate change
• In some areas, killing of turtles and collection of eggs for consumption
• Entanglement in marine debris
• Vessel strikes

Sources:

Sea turtle conservancy, 2024. https://conserveturtles.org/information-about-sea-turtles-an-introduction/

NOAA, n.d. https://www.fisheries.noaa.gov/sea-turtles#overview

Image: https://projectmanaia.at/blog/sea-turtles-of-mediterranean/

Information

Not applicable. This layer is not available in the MSP Challenge North Sea Edition.

Historically, there are some records of sea turtles observations in the North Sea (http://www.seaturtle.org/mtn/archives/mtn141/mtn141-2.shtml#:~:text=Leatherback%20turtles%20(Dermochelys%20coriacea)%20use,passing%20between%20Scotland%20and%20Norway.), however this seems to be occasional and do not indicate a constant presence of turtles in the area.

Information

Not applicable. This layer is not available in the MSP Challenge Baltic Sea Edition.

Information

Not applicable. This layer is not available in the MSP Challenge Clyde Marine Region Edition.

Information

Not applicable. This layer is not available in the MSP Challenge Adriatic Sea Edition.

Information

In the Eastern Mediterranean Sea only two species of sea turtles nest; the loggerhead turtle and the green turtle. The loggerhead turtle has been classified as Vulnerable by the International Union for Conservation of Nature and Natural Resources (IUCN) and the green turtle as Endangered.

Types

• Very Low Density
• Low Density
• Medium Density
• High Density
• Very High Density

Metadata

Data Source

Turtles is a month-by-month, computer generated data layer following calculations made by the ecosystem simulation (EwE). The simplified EwE Eastern Mediterranean model was adjusted for use in the MSP Challenge by Eyal Ofir.

For more information on how Ecopath-with-Ecosim (EwE) works, please visit our Wiki page or visit the official EwE website at https://ecopath.org.