Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New study examines the effects of catch-and-release fishing on sharks

31.01.2014
Researchers analyze blood chemistry, reflexes, and post-release survival of five coastal shark species in South Florida

A new study led by scientists at the University of Miami (UM) Abess Center for Ecosystem Science and Policy and the Rosenstiel School of Marine and Atmospheric Science investigated how several species of coastal sharks respond to stress from catch-and-release fishing. The results revealed that each of the shark species responded differently. Hammerhead sharks were by far the most vulnerable to fighting on a fishing line.

The UM scientists experimentally simulated catch-and-release fishing on five shark species – hammerhead, blacktip, bull, lemon and tiger sharks – in South Florida and Bahamian waters. Researchers took blood samples to examine stress, including pH, carbon dioxide and lactate levels, conducted reflex tests, as well as used satellite tags to look at their post-release survival. Fighting on a fishing line significantly affected the blood lactate levels of sharks, similar to what happens to humans during intense or exhaustive physical exercise, which has been linked to mortality in many species of fish. The study revealed that even with minimal degrees of fighting on a fishing line, hammerhead exhibited the highest levels of lactic acid build of all species studied, followed by blacktip, bull, lemon and tiger sharks. Tagging results also suggested that, after release, hammerheads were also prone to delayed mortality.

"Our results show that while some species, like tiger sharks, can sustain and even recover from minimal catch and release fishing, other sharks, such as hammerheads are more sensitive" said lead author and Abess Center Ph.D candidate Austin Gallagher. "Our study also revealed that just because a shark swims away after it is released, doesn't mean that it will survive the encounter. This has serious conservation implications because those fragile species might need to be managed separately, especially if we are striving for sustainability in catch and release fishing and even in bycatch scenarios."

Adds study co-author Dr. Neil Hammerschlag, a Research Assistant Professor at UM, "Many shark populations globally are declining due to overfishing. Shark anglers are some of the biggest advocates for shark conservation. Most have been making the switch from catch and kill to all catch and release. Our study helps concerned fisherman make informed decisions on which sharks make good candidates for catch and release fishing, and which do not, such as hammerheads."

The study, titled "Physiological stress response, reflex impairment and survival of five sympatric shark species following experimental capture and release," was published in the special theme issue "Tracking fitness in marine vertebrates "in the journal Marine Ecology Progress. The paper's co-authors are Austin J. Gallagher, Neil Hammerschlag, Joseph E. Serafy of the National Marine Fisheries Service in Miami and Steven J. Cooke of the Ottawa-Carleton Institute of Biology and Institute of Environmental Science in Ontario, Canada.

Check out a video to accompany this article: http://rjd.miami.edu/research/projects/stressed-out-fish To learn more about this research, please visit http://www.SharkTagging.com

About the University of Miami's Rosenstiel School

The University of Miami is one of the largest private research institution in the southeastern United States. The University's mission is to provide quality education, attract and retain outstanding students, support the faculty and their research, and build an endowment for University initiatives. Founded in the 1940's, the Rosenstiel School of Marine & Atmospheric Science has grown into one of the world's premier marine and atmospheric research institutions. Offering dynamic interdisciplinary academics, the Rosenstiel School is dedicated to helping communities to better understand the planet, participating in the establishment of environmental policies, and aiding in the improvement of society and quality of life.

Diana Udel | EurekAlert!
Further information:
http://www.rsmas.miami.edu

More articles from Studies and Analyses:

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>