Comparative physiological energetics of Mediterranean and North Atlantic loggerhead turtles

Although the western North Atlantic hosts the largest nesting assemblage of loggerhead turtles (Caretta caretta) in the world, their fine-scale habitat use beyond the nesting beach and how it effects reproductive output is still poorly understood. To characterize internesting and postnesting habitats used by loggerheads in the region, we satellite tracked 32 individual mature female turtles from a nesting beach in the southeastern Gulf of Mexico from 2009 to 2016. Thirteen of these turtles were tagged and tracked for two or more nesting seasons to assess fidelity to internesting movements, migratory pathway, and foraging site. Internesting movements for all turtles occurred over the West Florida Shelf in relatively close proximity to the nesting beach. Migratory pathways along the continental shelf led to foraging areas in four distinct regions: the southeastern Gulf of Mexico (n = 16 turtles), northeastern Gulf of Mexico (n = 8), Bahama Banks (n = 7), and Campeche Bank (n = 1). Individual turtles exhibited high fidelity to foraging sites across seasons, and 22 of the 32 tracked turtles shared overlapping foraging area utilization with at least one other individual during the tracking period. Loggerheads foraging closest to the nesting beach in the southeastern Gulf of Mexico were generally smaller than those foraging in other regions. This work highlights the importance of the West Florida Shelf for eastern Gulf of Mexico sea turtle rookeries. Identifying and managing the multiple in-water habitats used within and between nesting seasons will help sustain loggerhead turtle population recovery and maintenance.

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Sea turtles in the eastern margin of the North Atlantic: the northern Ibero-Moroccan Gulf as an important neritic area for sea turtles

Mediterranean Marine Science ◽

10.12681/mms.15835 ◽

2018 ◽

Author(s):

JUAN JESÚS BELLIDO LÓPEZ ◽

ESTEFANIA TORREBLANCA ◽

JOSÉ CARLOS BAEZ ◽

JUAN ANTONIO CAMIÑAS

Keyword(s):

North Atlantic ◽

Adult Stage ◽

Sea Turtles ◽

Atlantic Coast ◽

Chelonia Mydas ◽

Leatherback Turtles ◽

The North ◽

Loggerhead Turtles ◽

Kemp's Ridley ◽

Neritic Habitat

This study summarizes nearly 20 years (1997-2015) of tracking strandings of sea turtles along the Andalusian coast. In this period 2495 specimens were recorded, most of them loggerhead turtles Caretta caretta (92.6%) and leatherback turtles Demochelys coriacea (7.1%). Two other species were almost insinificant, green turtle Chelonia mydas (0.2%) and Kemp’s ridley Lepidochelys kempi (0.1%). Significant part of the turtles were recorded in the Atlantic coast, although in this area the incidence of alive specimens was low. Spring and summer were the seasons with more specimens stranded, probably related to warmer and more productive waters. The size of the loggerhead turtles observed highlights an important presence of inmature specimens in Andalusian waters, although mature individuals were not rare. In the case of leatherback turtles, adult stage is the only detected in the specimens recorded.These results, combined with the fact that the Atlantic coast has a large continental shelf and a high primary productivity near the coast, suggesting that the gulf of Cádiz may represent a neritic habitat used by the sea turtles. In this case, new and more effective politics of conservation are needed in order to protect sea turtles in this area.

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