Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


A dichotomy in migration patterns found for sea turtles in east Atlantic

Newfound differences in turtle behavior pose a conservation challenge

Studying members of a large population of loggerhead sea turtles that nest on the Cape Verde islands off of West Africa, researchers have found an unexpected dichotomy in turtle behavior: While some turtles leave the nesting grounds to feed on bottom-dwelling sea life in shallow coastal waters, others leave Cape Verde to roam the much deeper open ocean along the African coast and exhibit a distinct feeding strategy. Interestingly, while adults compose both groups, the coastal feeding strategy correlates with larger animal size. These new findings revise our understanding of the turtle’s life history and indicate that a multifaceted approach to fishing regulation--in both coastal and oceanic waters--will be required to effectively conserve these animals.

The findings are reported by Brendan Godley and colleagues at the Marine Turtle Research Group at the University of Exeter in Cornwall, Michael Coyne of the Marine Geospatial Ecology Lab at Duke University, and other members of an international team of researchers. The paper appears in the May 23rd issue of Current Biology.

Past studies had indicated that the loggerhead sea turtle (Caretta caretta), which reaches sexual maturity at about 30 years of age, typically undergoes a shift from an oceanic juvenile stage to a shallow-water, coastal adult stage. But the new findings--obtained by newly-improved methods for satellite tracking of the adult turtles’ geographical movements and diving patterns--show that the sexually mature adult population also includes oceanic animals and thereby reveal that adults in the eastern Atlantic occupy very different habitats and undertake two distinct foraging strategies.

The differing strategies correlate with body size, which may be linked to the different diets of the two groups. Turtles migrating to shallow coastal waters-the so-called neritic environment-were larger, and they feed on the arthropods and mollusks that are normally abundant in this food-rich ecosystem. In contrast, adults foraging in the open ocean are smaller, have a more limited capacity for diving, and most likely feed on a somewhat different set of prey that includes small, floating plants and animals.

Importantly, the correlations in animal size and foraging strategy suggest that the majority of adults in the Cape Verde population may undertake the oceanic strategy, rather than the primarily coastal existence previously thought to characterize adulthood. This means that two adult populations will need to be monitored for conservation efforts. And critically--because commercial and artisanal fishing occur in both the open ocean and coastal waters--the findings indicate that appropriate measures will be needed to regulate fishing efforts to reduce by-catch in the different environments. The fact that the oceanic adults were found in a large area, including international waters and waters from Mauritania to Guinea Bissau, indicates that efforts toward regulation and population monitoring will need to take place on a large scale.

Heidi Hardman | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>