Navigation Links
Leatherback sea turtle nests increasing in Florida
Date:4/4/2011

DURHAM, N.C. The number of endangered leatherback sea turtle nests at 68 beaches in Florida has increased by 10.2 percent a year since 1979, according to a new Duke University-led study published in the current issue of the journal Ecological Applications.

Some beaches posted annual increases of more than 16 percent, others as low as 3.1 percent.

The population boom of turtle nests in the Sunshine State mirrors trends observed for other Atlantic leatherback sea turtle populations and is "very encouraging news," says Larry B. Crowder, director of the Duke Center for Marine Conservation. "It suggests that conservation and recovery efforts mandated under the Endangered Species Act are paying off region-wide."

The growth has likely been fueled in part by improved monitoring and protection of nesting beaches over the last 30 years, Crowder says, but other less benign factors may also be at work.

"Nesting is increasing even where beach protection has not been enhanced," he says. "Changing ocean conditions linked to climate variability may be altering the marine food web and creating an environment that favors turtles by reducing the number of predators and increasing the abundance of prey, particularly jellyfish."

With plenty of jellyfish to munch on, breeding-age female leatherbacks may be able to build up fat reserves more quickly, allowing them to nest more frequently, says Kelly Stewart, lead author of the study. Stewart received her Ph.D. from Duke in 2007 and conducted the research on Florida's leatherback sea turtles as her dissertation research. Crowder was her faculty adviser.

Reduced populations of large predators, including the collapse of shark populations in the northwest Atlantic over the past decade, may be playing an even larger role in the turtle boom by decreasing at-sea mortality rates for juvenile and young adult turtles, she says.

Despite being a small population scientists estimate fewer than 1,000 leatherbacks nest on Florida beaches the increases in nest counts there may help achieve objectives of the federal Endangered Species Act-mandated recovery plan, Stewart says.

News for leatherback populations elsewhere is not so encouraging, however. Populations have plummeted at eastern Pacific nesting beaches in Mexico and Costa Rica, which once hosted thousands of female leatherbacks each year. Extirpation, or local extinction of the species, may be imminent on those beaches.

"The good news here is that while most sea turtles continue to decline, some sea turtles are increasing. We need to understand why they are increasing as much as why they are declining so we can transfer this understanding to other at-risk species, like Pacific leatherbacks," says Crowder.

Stewart, Crowder and their colleagues modeled the 30-year nest counts on Florida beaches using a type of multilevel statistical analysis called Poisson regression, which is frequently used to model counts affected by multiple, often random, factors.

Nest counts are the most reliable way of assessing trends in sea turtle populations because they spend most of their lives in the open ocean, where changes in abundance are difficult to detect.

Stewart is now based at the National Oceanic and Atmospheric Administration's Southwest Fisheries Science Center in LaJolla, Calif., as a National Research Council postdoctoral fellow. Prior to that, she served as a postdoctoral research associate at the Duke Center for Marine Conservation.


'/>"/>

Contact: Tim Lucas
tdlucas@duke.edu
919-613-8084
Duke University
Source:Eurekalert

Related biology news :

1. Why leatherback turtles linger in South Pacific Gyre, and why it matters
2. How diving leatherback turtles regulate buoyancy
3. Scientists identify worlds largest leatherback turtle population
4. Scientists call for protected swimways for the endangered leatherback sea turtle
5. Migrating sea turtles have magnetic sense for longitude
6. Shellshock: New report lists 25 most endangered turtle species
7. Turtle populations affected by climate, habitat loss and overexploitation
8. Epic journeys of turtles revealed
9. Atlantic sea turtle population threatened by egg infection
10. Turtle, dugongs at risk under climate change
11. New thick-shelled turtle species lived with worlds biggest snake
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/21/2016)...   Neurotechnology , a provider of high-precision ... that the MegaMatcher On Card fingerprint matching algorithm ... NIST Minutiae Interoperability Exchange (MINEX) III ... of the evaluation protocol. The ... fingerprint templates used to establish compliance of template ...
(Date:11/17/2016)... INDUSTRY, Calif. , Nov. 17, 2016  AIC announces that it has just ... servers in organizations that require high-performance scale-out plus high speed data transfer storage solutions. ... ... ... Setting up a ...
(Date:11/15/2016)... , Nov 15, 2016 Research and Markets ... Forecast to 2021" report to their offering. ... ... 16.18 Billion by 2021 from USD 6.21 Billion in 2016, growing ... Growth of the bioinformatics market is driven by the growing ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... , Dec. 8, 2016  Anaconda BioMed S.L., ... development of the next generation neuro-thrombectomy system for the ... of Tudor G. Jovin, MD to join its Scientific ... as a strategic network of scientific and clinical experts ... development of the ANCD BRAIN ® to its ...
(Date:12/8/2016)... , Dec. 8, 2016  Soligenix, Inc. ... biopharmaceutical company focused on developing and commercializing products ... unmet medical need, announced today the long-term follow-up ... SGX942 (dusquetide), a first-in-class Innate Defense Regulator (IDR), ... head and neck cancer patients undergoing chemoradiation therapy ...
(Date:12/8/2016)... 8, 2016  Partnering to fuel Philadelphia,s ... Partners of Southeastern Pennsylvania (" ... company of Independence Blue Cross; and Safeguard Scientifics ("Safeguard") ... for a $6 million funding initiative over a four ... Responding to a burgeoning economic vitality in digital ...
(Date:12/7/2016)... Mich. , Dec. 7, 2016 Neogen ... has named Dr. Dan Kephart as its ... company. Kephart will assume his responsibilities at Neogen effective ... and development director for the agribusiness unit of Thermo ... safety development at Life Technologies. His extensive industry experience ...
Breaking Biology Technology: