
Friday 25 January
Kingdom | Animalia |
Phylum | Chordata |
Class | Reptilia |
Order | Testudines |
Family | Cheloniidae |
Genus | Caretta (1) |
The loggerhead is one of the most widespread of all the marine turtles and also the most highly migratory, with individuals known to cross the Atlantic and Pacific Oceans (2). This turtle's common name comes from its relatively large head, which contains powerful jaws (5). The carapace of the adult turtle is a reddish-brown colour, whilst the underneath (or plastron) is more yellow in appearance (6).
Adults are primarily carnivorous, using their powerful jaws to crack open crustaceans such as crabs and even seemingly impenetrable molluscs such as the queen conch (Strombus gigas) and giant clam (Tridacna spp.) (7). Loggerheads may reach sexual maturity at around 35 years old, and females appear to nest an average of three to five times in one breeding season, returning to breed every couple of years (8). Nesting occurs at night throughout the summer; females drag themselves out onto beaches beyond the high-tide mark and dig nests (around 40 centimetres deep) into which around 100 eggs are laid (2). Hatchlings and small juveniles appear to spend some time in pelagic environments, often drifting amongst rafts of sargassum (brown algae) and/or flotsam in the open ocean before migrating to benthic habitats in shallower, coastal waters (6).
Found throughout the world in subtropical and temperate waters, loggerheads are the most common turtle in the Mediterranean Sea (7) and western North Atlantic Ocean (2). Nesting occurs in more temperate regions than for other sea turtle species and the largest breeding population is currently found in the southeastern United States from North Carolina throughout Florida (2).
Long-distance migration makes loggerheads particularly vulnerable to accidental capture by commercial fisheries (bycatch), and turtles can become caught in shrimp trawler nets or entangled in longlines, leading to mortal injuries or death by drowning (7). Fisheries captured 32,000 loggerhead turtles in the Atlantic and 10,500 in the Gulf of Mexico in 1987 alone (7). Loggerheads are unlikely to be deliberately hunted for their meat, which is not considered a delicacy, but eggs are collected in many parts of the world (7). Habitat loss or disturbance, particularly developments on nesting beaches, is the main threat to this species (9).
Loggerheads are nominally protected throughout most of their range and international trade is prohibited by their listing on Appendix I of the Convention on International Trade in Endangered Species (CITES) (3). Nesting occurs on relatively few protected beaches however, and increased protection remains a conservation priority. In Oman, if locals must collect eggs, they are encouraged to only take them from below the high water mark, thus securing an income without harming the turtles' survival chances (9). Turtle Excluder Devices (TEDs) fitted to shrimp trawlers can help prevent bycatch by only allowing shrimp-sized objects to enter the nets, and these are now being adopted by many of the world's fisheries (7).
For more information on the loggerhead turtle see:
NOAA fisheries:
www.nmfs.noaa.gov/pr/species/turtles/loggerhead.htm
Authenticated (11/7/02) by Mike Frick, Caretta Research Project.
http://members.aol.com/WassawCRP/
Image credit
© Howard Hall / gettyimages.com
Getty Images
101 Bayham Street
London
NW1 0AG
United Kingdom
Tel: +44 (0) 800 376 7981
sales@gettyimages.com
http://www.gettyimages.com
Link to this photo
Embed this Arkive thumbnail link ("portlet") by copying and pasting the code below.
Terms of Use - The displayed portlet may be used as a link from your website to Arkive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.
Read more about
MyARKive
MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite Arkive images and videos and share them with friends.
Play the Team WILD game:
Team WILD, an elite squadron of science superheroes, needs your help! Your mission: protect and conserve the planet’s species and habitats from destruction.
This species is featured in:
This species is featured in the Mediterranean Basin eco-region