LOGGERHEAD TURTLES – A NATURAL HISTORY
The loggerhead turtle is a keystone species in the world’s oceans. Dependant on its mainly invertebrate diet it plays a major role in the food chain, and its digestive system processes shells that provides other animals with a constant source of calcium. By digging for food these turtles even change the community structure on the ocean floor, both biologically and physically.
Loggerhead turtles are air-breathing reptiles that inhabit tropical and subtropical seas throughout the world. They are one of the most widespread of all the marine turtles and also the most migratory, with individual’s known to cross the Atlantic and Pacific Oceans.
Their name is derived from their large head. They have no ‘teeth’ and their jaws are modified “beaks”. Their ribs fused millions of years ago to form their shell. Their streamlined bodies and large flippers make them remarkably adapted to life at sea.
Sea turtles, however, maintain close ties to the land as females must come ashore to lay their eggs in the sand. All loggerheads start life as tiny hatchlings on beaches, leaving their nests at 2 in (5 cm) in length. Most nesting occurs in two parts of the world: in the Middle East at Masirah Island, Oman, and in North America on Florida’s Atlantic coast where Turtle was filmed. Hatchlings usually emerge at night and orientate themselves towards the brightest light and the lowest elevation, which in a natural environment is the ocean.
A few days after hatchlings enter the ocean they start to feed on small animals, bits of debris, and even oil droplets. These tiny turtles live at or near the surface and swim in the prevailing currents of the open ocean. Many hatchlings in the Atlantic and Caribbean ride the Gulf Stream current, where they soon find the mats of floating Sargassum algae. Here they eat as many as 100 different species of plants and animals, including insects that have blown out to sea and landed on the mats, and more natural marine inhabitants such as barnacles, small crab larvae and fish eggs. Starting their journey under the protection of the Sargassum they wander the ocean, spending 6-12 years as juveniles at sea. In the Atlantic Ocean most of their time is spent in the waters around the Azores and Madeira Islands.
Sea turtles in general migrate hundreds, and sometimes thousands of miles from their feeding ground to their nesting beaches. The loggerhead’s journey is one of the longest in the animal kingdom. After a journey of up to 25 years, the adult females return faithfully to the beaches where they were born to complete the cycle of life. She rises from the sea to lay her eggs on a sandy beach before returning, with relief, and disappearing into the churning ocean.
Download the loggerhead factsheet here.
Download an amazing tutle identification guide courtesy of seaturtle.org right here.
Information on this website was sourced from the following:
Sea Turtles, A Complete Guide to Their Biology, Behaviour, and Conservation
By James R. Spotila. The John Hopkins University Press. 2004. PP. 227
The Biology of Sea Turtles
Edited by Peter Lutz and John Musick. CRC Press. 1997. PP.432