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Marine Resources


February 2012 Issue

Scientists' Model Helps Squid Fishermen Avoid Butterfish
Scientists are helping squid fishing boats avoid getting unwanted butterfish caught in their nets by developing a model to predict where butterfish populations are most likely to be, the University of Delaware announced in January.

The model combines NASA satellite data with radar information on ocean currents and an understanding of butterfish behavior. The scientists used the data to create color overlays on Google Earth maps and beamed their daily butterfish forecast map via satellite phone to a fishing vessel about 200 miles offshore as part of an eight-day field experiment to test the accuracy of the predictions. The information was received through an underwater robot glider that was strapped to the top of the vessel. The fishermen used the map to sample areas where scientists predicted butterfish would or would not be. The fishermen then sent catch data back to the onshore team through the glider.

The hope is to give fishermen another tool beyond sonar and past experience in deciding where to trawl. The fishermen said they could use the model in a way similar to a weather forecast, providing general guidance on when and where to drop their nets.

Results of the experiment showed that sometimes the model was slightly off, while the fishermen's guesses were correct. Other times, the model suggested successful spots the fishermen would not have otherwise tried. Overall, the model pointed the boat in the right direction to avoid butterfish based on features of the ocean's surface, the University of Delaware said.

"We were taking real-time observations from satellites and high-frequency radar and sending it to fishermen to guide their fishing efforts," said Matthew Oliver, assistant professor of oceanography at the University of Delaware, who worked on the model development. "I think it may have been the first time anything has been done like that." For more information, visit www.udel.edu.

Sunlight, Oil a Deadly Combo For Pacific Herring Embryos
The 2007 Cosco Busan incident, which spilled 54,000 gallons of oil into California's San Francisco Bay, had an unexpectedly devastating impact on Pacific herring embryos in the following two years, a study by the University of California, Davis, and NOAA found.

The study, published in the Proceedings of the National Academy in December, found that bunker oil accumulated in naturally spawned herring embryos, then interacted with sunlight during low tides to kill the embryos in shallow water. The study suggests that even small oil spills can have a large impact on marine life and that common chemical analyses of oil spills may be inadequate. The Cosco Busan oil spill contaminated spawning habitats for the largest U.S. coastal population of Pacific herring a month before spawning season.

"Based on our previous understanding of the effects of oil on embryonic fish, we didn't think there was enough oil from the Cosco Busan spill to cause this much damage," study co-author Gary Cherr said. "We didn't expect that the ultraviolet light would dramatically increase toxicity in the actual environment, as we might observe in controlled laboratory experiments."

Three months after the spill, caged embryos at oiled sites showed nonlethal heart defects typical of oil exposure. But embryos from the shallower, intertidal zone not only exhibited the nonlethal heart defects, they also showed surprisingly high rates of dead tissue and mortality unrelated to heart defects. The high death rates did not seem to be caused by natural or man-made causes unrelated to the spill, the researchers said. No toxicity was observed in embryos from unoiled sites, even those near major highways.

Embryos sampled two years later from oiled sites showed a modest rate of heart defects but no increased death rates, the researchers said. For more information, visit www.pnas.org.

NOAA Grant Funds Study Of Ciguatera Fish Poisoning
NOAA has awarded more than $550,000 to scientists researching the causes of ciguatera fish poisoning in the Gulf of Mexico and Caribbean, the agency said in December. The award is the first in a five-year grant that could total about $4 million.

The aim of the research is to help prevent the most common form of algal toxin-induced seafood poisoning in the world, which affects tens of thousands of people who eat reef fish annually.

Michael Parsons, professor of marine science and director of the Coastal Watershed Institute at Florida Gulf Coast University, will lead a team with scientists from the Woods Hole Oceanographic Institution, the University of Texas Marine Science Institute, the University of South Alabama, the University of Veracruz, in Mexico, the U.S. Food and Drug Administration Gulf Coast Seafood Laboratory and the University of the Virgin Islands. For more information, visit www.noaa.gov.

Oceana Calls for More MPAs in the Baltic Sea
Oceana published in December a report on marine habitats that calls for increasing the marine protected areas (MPAs) in the Baltic Sea from 12 percent to 30 percent.

The organization has proposed establishing nine MPAs in Sweden, Finland and Denmark, totaling 3,500 square kilometers. During a two-month research expedition in spring last year, Oceana documented habitats in the Baltic Sea that could be vulnerable to human activities such as bottom trawling, including sponge aggregations and special types of coral gardens in the Kattegat and in the Sound.

By incorporating its proposed areas, the total protection percentage in the Baltic Sea would increase from 12 to 13 percent, Oceana said. Although the 10 percent international conservation target, set to each marine region by the the World Summit on Sustainable Development and the Convention on Biological Diversity, has already been reached in the Baltic Sea, individual countries have contributed area to the network unequally. Only Germany, Poland, Denmark and Estonia have exceeded 10 percent with 29.7, 24.3, 22.1 and 16.5 percent, respectively, according to the report. For more information, visit www.oceana.org.


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