Navigation Links
How learning more about mass nesting can help conserve sea turtles
Date:10/18/2011

Ecologists are a step closer to understanding one of nature's most extraordinary sights the 'arribada' or synchronised mass nesting of female olive ridley sea turtles. The new study, published today in the British Ecological Society's Journal of Animal Ecology, is the first to combine three different approaches genetics, demography and behaviour, and the results should help conserve these vulnerable marine creatures.

The study, lead by Virginie Plot of the National Center for Scientific Research (CNRS) in France, gathered three sets of data. First, to get an accurate estimate of the size of the olive ridley population in French Guiana, the ecologists monitored nesting beaches at Cayenne and Remire-Montjoly every night during the nesting season (May to September) each year between 2002 and 2010.

Then, to learn more about how the turtles behave before coming ashore, they attached satellite data loggers to the shells of 10 individuals. By recording data every 10 seconds and sending them by satellite every time the turtles surface for breathing, these units gave a detailed picture of the turtles' geographic location, the depth and duration of their dives and the temperature of the water.

Finally, the team took skin samples from the turtles so they could investigate the variability of their DNA. These tests reveal the genetic diversity of the population and also allow researchers to estimate past population levels.

The results show that although olive ridley numbers in French Guiana have increased during the past 10 years, the population suffered a massive collapse in the past 2,000 years.

According to Ms Plot: "Looking at the DNA of these turtles tells us that they come from a much larger population, one that has collapsed by 99% over the past 2,000 years. This is one of the sharpest collapses ever reported in large species and their population in French Guiana remains at a critical level."

The researchers found that even though fewer than 2,000 olive ridleys nest in French Guiana, they still synchronise their breeding, all leaving the sea to lay their eggs on the beach on the same nights. Until now, this behaviour had only been recorded among large populations of olive ridleys in India, Costa Rica and Mexico.

And thanks to the data loggers, the researchers gained a unique insight into how the turtles behave at sea between successive nesting events. During the first part of the nesting season individual turtles show a wide range of diving behaviour. Then, triggered by a cue that remains a mystery, they all start behaving in the same way, returning to the nesting beach and performing regular, systematic and shallow dives.

Together with local conservation efforts, the fact that such a small population of olive ridleys can synchronise their reproduction may explain why the number of nests laid every year in French Guiana has increased three-fold over the past 10 years. But, Ms Plot warns, this group behaviour also makes them more vulnerable.

"In terms of conservation, gathering together at the same time and in the same place to nest makes female olive ridleys vulnerable to human disturbance and could jeopardise their survival. By mapping more accurately how the turtles gather prior to coming ashore our study should help protect them," she says.


'/>"/>

Contact: Becky Allen
beckyallen@ntlworld.com
44-122-357-0016
Wiley-Blackwell
Source:Eurekalert  

Related biology news :

1. Moths with a nose for learning
2. Baby talk: The roots of the early vocabulary in infants learning from speech
3. New report on science learning at museums, zoos, other informal settings
4. DREAM: 1 gene regulates pain, learning and memory
5. At WPI, some students are learning its OK to peek
6. Learning how the pieces responsible for interpreting the human genome work
7. MU study finds connection between evolution, classroom learning
8. Scientists are learning more about big birds from feathers
9. Scientists devise efficient way of learning about complex corn traits
10. Why one way of learning is better than another
11. Habit-learning device will lower energy bills under new clean energy cashback scheme
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
How learning more about mass nesting can help conserve sea turtles
(Date:11/21/2016)... 2016   Neurotechnology , a provider of ... announced that the MegaMatcher On Card fingerprint matching ... the NIST Minutiae Interoperability Exchange (MINEX) III ... steps of the evaluation protocol. ... of fingerprint templates used to establish compliance of ...
(Date:11/17/2016)... it has just released a new white paper authored by Zettar that covers the ... transfer storage solutions. Photo - http://photos.prnewswire.com/prnh/20161116/440463 ... ... ... Setting up a high performance computing or HPC system can be a complicated endeavor ...
(Date:11/15/2016)... -- Research and Markets has announced the addition of ... to their offering. ... The global bioinformatics ... USD 6.21 Billion in 2016, growing at a CAGR of 21.1% ... market is driven by the growing demand for nucleic acid and ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... Dec. 2, 2016 More than $4.3 million was ... Medals dinner ( DHMD ). The gala was held at the ... York City and honored Alan Alda ... to health and medicine and the public understanding of science. ... 2006, the event has raised $40 million for the Laboratory,s ...
(Date:12/2/2016)... ... 2016 , ... ACEA Biosciences, Inc. announced today that it will be presenting ... the World Conference on Lung Cancer 2016, taking place in Vienna, Austria December 3rd-8th. ... trials for AC0010 in patients with advanced non-small cell lung cancer harboring the EGFR ...
(Date:12/2/2016)... ... December 01, 2016 , ... DrugDev believes the ... and a beautiful technology experience. All three tenets were on display at the 2nd ... leaders from over 40 sponsor, CRO and site organizations to discuss innovation and the ...
(Date:12/2/2016)... December 2, 2016 The immunohistochemistry (IHC) ... at a CAGR of 7.3% during the forecast period of 2016 ... diagnostic laboratories segment accounted for the largest share of immunohistochemistry (IHC) ... , ... global immunohistochemistry (IHC) market spread across 225 pages, profiling 10 companies ...
Breaking Biology Technology: