Saving Seafood

Your dinner might be swimming North thanks to climate change, Rutgers study says

May 18, 2018 — Climate change is making oceans warmer and the fish are taking flight.

And that could have a big impact on New Jersey’s $7.9 billion fishing industry according to a new Rutgers-led study published Wednesday.

Aquatic life has a narrow tolerance for temperature range, so as the water heats up species populations are shifting northward to find suitable habitat according to Malin Pinksy, a co-author of the study and an assistant professor in Rutgers’ Department of Ecology, Evolution and Natural Resources.

By 2100, the Atlantic’s temperature off the Jersey Shore could rise to levels currently seen in Virginia. That could lead to species like black sea bass and summer flounder, both staples of New Jersey’s fishing industry, leaving the area and being replaced by more southern species like Atlantic Croaker.

Pinsky said the most dramatic example of a shifting fishery is the Atlantic Cod. The species could lose 90 percent of its habitat in U.S. waters by 2100 in a worst case scenario.

Read the full story at NJ

 

Biologists Have Recorded The Loudest Known Fish And Oh Boy

December 21, 2017 — Each year between February and June, the fish gather to spawn in Mexico’s Colorado River Delta. The fish, a type of croaker called the Gulf corvina, meet in water as cloudy as chocolate milk. It’s a reunion for the entire species, all members of which reproduce within a dozen-mile stretch of the delta.

When the time is right, a few days before the new or full moons, the male fish begin to sing. To humans, the sound is machine guns going off just below the waterline. To female fish, the rapid burr-burr-burr is a Bing Crosby croon. Make that Bing cranked up to 11.

Marine biologists who recorded the sound describe the animals as the “loudest fish ever documented,” said Timothy J. Rowell, at the Scripps Institution of Oceanography in California. Rowell and Brad E. Erisman, a University of Texas at Austin fisheries scientist, spent four days in 2014 snooping on the fish with sonar and underwater microphones. The land surrounding the delta is desolate, Rowell said. Fresh water that once fed wild greenery has been diverted to faucets and hoses.

But the delta is alive with the sound of fish. “When you arrive at the channels of the delta, you can hear it in the air even while the engine is running on the boat,” Rowell said. Sound is measured differently in water than in air; still, the fish are as loud as lawn mowers, Rowell said.

Read the full story from the Washington Post at Science Alert

 

ASMFC Releases Report on Sciaenid Fish Habitat

March 29, 2017 — The following was released by the Atlantic States Marine Fisheries Commission: 

Arlington, Va. — The Atlantic States Marine Fisheries Commission has released the 14th report in its Habitat Management Series entitled, Atlantic Sciaenid Habitats: A Review of Utilization, Threats and Recommendations for Conservation, Management and Research. Prepared by ASMFC staff, sciaenid experts, and a subset of the Commission’s Habitat Committee, the report is the most comprehensive compilation of habitat information to date on Commission-managed and other common sciaenid species found throughout the Western Atlantic. These species include Atlantic croaker, black drum, red drum, spot, spotted seatrout, weakfish, northern kingfish, southern kingfish and Gulf kingfish. The report provides a habitat description for all stages of each species’ life cycle, their associated Essential Fish Habitats and Habitat Areas of Particular Concern (when applicable), threats and uncertainties to their habitats, and recommendations for habitat management and research. It was developed to serve as a resource for fisheries managers to use when amending existing fishery management plan (FMPs).

Sciaenids are found throughout the Western Atlantic Ocean from Maine to Mexico, in shallow coastal waters and larger bays and estuaries, including their tributaries. They utilize a variety of habitats throughout their life stages, including estuaries, salt marshes, freshwater marshes, oyster reefs, sea grasses and mud banks/shores. Because of the way different species of sciaenids use various types of habitats throughout their life, several different habitats are key for maintaining healthy populations.

Estuarine habitats are particularly important to many sciaenids at every life stage. In the Mid-Atlantic Bight, as many as 14 species can be present in estuaries as larvae, juveniles, or adults over the course of a year. Weakfish, for example, use estuaries as primary spawning habitat, while Atlantic croaker and spot use them as nurseries and seasonal adult foraging grounds. Young sciaenids play important roles as both predators and prey in these habitats.

Temperature, salinity, and dissolved oxygen vary considerably in estuarine environments and these factors are known to affect sciaenid growth rates, spawning, and spatial and temporal distribution. As a group, sciaenids are habitat generalists rather than specialists and may therefore be relatively resilient to changes in environmental factors. However, Atlantic coast estuaries have been profoundly altered. Despite their ability to take advantage of a range of habitats, sciaenids are not immune to habitat degradation or suboptimal conditions, especially in the face of climate change. 

Increasingly dense human populations along our coastlines threaten the health of estuaries and coastal waters, including sciaenid habitats. Widespread development, beach renourishment, dredging, overfishing, coastal armoring, pollution, and other human impacts have significantly altered the physical and chemical environments of estuarine and marine waters. Changes in hydrologic processes and runoff characteristics can increase turbidity and sedimentation and decrease light transmittance, which may lead to the loss of submerged aquatic vegetation. Human-caused alterations to the estuarine environment have been linked to changes in hydrography and salinity regimes, as well as food web modification, which can eventually reduce the quality of habitat for sciaenids and other estuarine-dependent fish.

The Commission would like to thank the following individuals for their contributions to the report: Jay Odell, Brian Boutin and Kate M. Wilke with The Nature Conservancy; Douglas H. Adams and Kent Smith with Florida Fish and Wildlife Conservation Commission; William Collier II, South Atlantic Fishery Management Council; Alison Deary, University of Southern Mississippi; James A. Johnson, Jr., North Carolina Department of Environmental Quality; Stephen R. Midway, Louisiana State University; January Murray, Georgia Department of Natural Resources; and Lisa N. Havel and Melissa W. Yuen, Atlantic States Marine Fisheries Commission.

The report is available online at http://www.asmfc.org/files/Habitat/HMS14_AtlanticSciaenidHabitats_Winter2017.pdf. Species-specific chapters are also available on the Commission’s website, www.asmfc.org, on the respective species pages (on the left navigation bar under Quick Links). For more information, please contact Lisa Havel, Habitat Coordinator, at LHavel@asmfc.org. 

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PR17-15

A PDF of the press release can be found at –http://www.asmfc.org/uploads/file/58dc0346pr15AtlanticSciaenidHabitats_Release.pdf.