Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Accidental Sea Turtle Deaths Drop by 90 Percent

15.09.2011
Improvements in fishing equipment seem to be preventing lethal 'bycatch'

The number of sea turtles accidentally caught and killed in fishing gear in United States coastal waters has declined by an estimated 90 percent since 1990, according to a new study by researchers at Duke University Project GloBAL and Conservation International.

The report, published in the scientific journal Biological Conservation, credits the dramatic drop to measures that have been put into place over the last 20 years to reduce bycatch in many fisheries, as well as to overall declines in U.S. fishing activity.

The study's authors estimate that 4,600 sea turtles die each year in U.S. coastal waters.

Before measures to reduce bycatch were put in place, total sea turtle takes surpassed 300,000 annually. Of these, 70,000 turtles were killed.

The study used data collected from 1990 to 2007 by the National Marine Fisheries Service (NMFS) to determine bycatch rates across more than 20 fisheries operating in Atlantic waters from the Gulf of Mexico to the Canadian border, and in the Pacific Ocean, along the West coast and around Hawaii.

It found that overall turtle bycatch rates, including both fatal and nonfatal run-ins, have fallen about 60 percent since 1990.

Shrimp trawls in the Gulf of Mexico and southeastern U.S. accounted for up to 98 percent of all by-catch takes and deaths during the study period.

All six marine turtle species that occur in U.S. waters are categorized as threatened or endangered on the U.S. Endangered Species List. They are loggerheads, leatherbacks, hawksbills, olive ridleys, Kemp's ridleys and green sea turtles.

Bycatch is an acute threat to sea turtle populations worldwide. High bycatch rates can be indicative of unsustainable fishing practices that negatively impact the health of marine ecosystems.

"The reduction of bycatch and mortality shows important progress by NMFS, which serves as a model for reducing sea turtle bycatch in other parts of the world," says Elena Finkbeiner, a PhD student at Duke and lead author of the paper. "Our findings show that there are effective tools available for policymakers and fishing industries to reduce sea turtle bycatch, as long as they are implemented properly and consistently."

Among the mitigation strategies that have helped reduce bycatch are: the use of circle hooks and dehooking equipment in longline fisheries, to reduce the severity of turtle injuries; the use of turtle excluder devices (TEDs) in shrimp trawl nets to allow captured sea turtles to escape; and the implementation of time-area closures to restrict fishing activities at times and places turtles are most likely to be present in the highest numbers.

Piecemeal regulation remains a problem, the study notes. Sea turtles are currently managed on a fishery-by-fishery basis, which means that bycatch limits are set for each fishery without accounting for the overall population impacts of all the takes added together. This fragmented approach leads to total allowed takes that exceed what sea turtle populations can sustain.

"Bycatch limits must be set unilaterally across all U.S. fisheries with overall impacts to populations in mind, much as it's done for marine mammals," says co-author Bryan Wallace, director of science for Conservation International's Marine Flagship Species Program and adjunct faculty member at Duke's Nicholas School of the Environment.

The researchers note that actual bycatch rates are likely higher than what the study reports because in many fisheries, particularly the shrimp trawl fishery, the number of on-board observers who document bycatch on fishing vessels is low relative to the sheer volume of fishing that is occurring.

"This paper provides a baseline to examine what is working and what can be improved in preventing sea turtle bycatch," Finkbeiner says. "It (makes) a strong case for the need for increased observer coverage and bycatch reporting."

Tim Lucas | EurekAlert!
Further information:
http://www.duke.edu

More articles from Ecology, The Environment and Conservation:

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht World Water Day 2017: It doesn’t Always Have to Be Drinking Water – Using Wastewater as a Resource
17.03.2017 | ISOE - Institut für sozial-ökologische Forschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>