Science

In a study sure to enrage extreme greenies everywhere, scientists in California have discovered that bottom trawling may not be systematic environmental pillage.

In fact, it may even be good for the seabed.

As reported in the latest issue of New Scientist, a five-year study by The Nature Conservancy is looking at the impact of bottom trawling on a strip of seabed 23km off Morro Bay, between Los Angeles and Monterey.

The scientists marked out eight plots, each 1km by 330m, that had not been trawled for a decade or more. Four would remain untouched and four would be trawled.

Last year the trawling zones were hit twice and  photographs of the seabed taken after each trawl. More photographs were taken six and 12 months later.

"Early signs indicate that marine life survived, even thrived, after last year's trawls," the New Scientist wrote. "Donna Kline, a fish ecologist at California State University in Monterey Bay, thinks that far from destroying a habitat, the trawl may have created a new one by etching grooves into the flat bottom."

This would be a remarkable conclusion, but it is way too early to be sure. A more intensive series of five trawls in each zone took place last month and time must pass before the impact can be assessed. Any conclusions may also be inapplicable to New Zealand seas.

Still, it is an interesting study.

Read the complete story from Business Day.

 

PLEASE NOTE:

The Nature Conservancy had concerns about the headline added to Mr. Hunter's article and submitted the following:

To the editor:

Tim Hunter’s recent article (“Bottom Trawling is Good,” November 30.) is a mischaracterization of The Nature Conservancy’s five-year trawl impact and recovery study which is only in the second year of research.

It’s inaccurate and premature to make a claim like the article’s headline that trawling is good for seabeds; our study aims to quantify the impacts of bottom trawling in soft bottom habitats on the continental shelf off California, as well as the recovery of those habitats over time, and not to make a value judgment about trawling. At this stage, we are still in the long process of analyzing dozens of sediment samples, hours of video footage and hundreds of photos from the first year of data and do not yet have any results to report. This is a five-year study, and no conclusions should be drawn until the full study has been completed and due diligence given to the scientific analysis of the data.

The article should have focused on the amazing collaboration between a conservation group, academics and fishermen on a unique study that, when results are in, will help inform best management. This study is part of a broader Central Coast Groundfish Project that over the past four years has resulted in the protection of 3.8 million acres of seafloor habitat from bottom trawling and reduced trawling effort in the region through private buyouts and conversion of trawl effort to hook and line. We are working closely with local fishing communities and other partners to improve the environmental and economic performance of the groundfish fishery in California. For further information, see http://www.nature.org/wherewework/northamerica/states/california/initiatives/ccgp.html

Mary Gleason
Senior Scientist
The Nature Conservancy

 

 

 

 

 

 

 

Branch and his co-authors are the first to combine so many trawl surveys for analysis – no one had combined more than a handful before. The trawl survey data came from efforts started three years ago by fisheries scientists and ecologists gathered at the National Center for Ecological Analysis and Synthesis in Santa Barbara, Calif. They brought together worldwide catch data, stock assessments, scientific trawl surveys, small-scale fishery data and modeling results. What emerged is the most comprehensive set of data yet for fisheries researchers and managers.

It paints a different picture from previous catch data and has revealed another major new finding: On a global scale humans don’t appear to be fishing down the food web, Branch said.

The new catch data reveal that, following declines during the 1970s in the average trophic levels of fish being caught, catches of fish at all trophic levels have generally gone up since the mid-80s. Included are high-trophic predators such as bigeye tuna, skipjack tuna and blue whiting.

“Globally we’re catching more of just about everything,” Branch said. “Therefore relying on changes in the average trophic level of fish being caught won’t tell us when fishing is sustainable or if it is leading to collapse.” That’s because when harvests of everything increase about equally, the average trophic level of what is caught remains steady. The same is true if everything is overfished to collapse. Both scenarios were modeled as part of the Nature analysis.

Read the complete story from Newswise.

 

SARASOTA — One way to keep tabs on the real impact of the Deepwater Horizon disaster on the Gulf of Mexico, a scientific conference decided Tuesday, is to watch what happens to the lowly bait fish: the menhaden, the mullet, the sardines.

The deaths of dolphins and sea turtles due to the oil spill have garnered a lot of headlines. And there are concerns the spill may push sharks and bluefin tuna to the brink of extinction.

But they're not the basis of the gulf's food chain.

On the other hand, "the bait fish are so important to the whole ecosystem that if something happens there, it will have a cascading effect right up to the top predators," said William Hogarth, dean of the college of marine sciences at the University of South Florida.

Read the complete story from the St. Petersburg Times.

 

 

 

 

 

 

GULF OF MEXICO — Scientists are starting to believe the most powerful environmental effect stemming from the BP oil spill may have nothing to do with the millions of gallons of petroleum loosed in the Gulf of Mexico.

Instead, ongoing research suggests the federal closure of the richest portion of the Gulf to all fishing through the spring and summer months resulted in dramatic increases in the abundance of numerous marine creatures, from shrimp to sharks.

Scientists said the forced closure illustrates the profound influence fishing pressure has on the marine world, though a federal fisheries regulator said many other factors might be at play.

Read the complete story from Alabama Live.

 

 

 

 

 

 

The benefits of supplementing diets with fish meal have been demonstrated in a number of species. Immunity and overall health are among some of the potential positive effects.

Fish meal has historically been used as a protein source in manufactured diets for animals ranging from beef cattle to poultry to laboratory animals. Fish meal is a concentrated source of high quality protein composed of highly digestible essential amino acids. Fish meal has one of the best overall amino acid profiles of any single protein source. In addition, fish meal is also an excellent source of omega 3 fatty acids, like DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), which have been shown to improve health by preventing cardiovascular disease, lowering serum triglycerides, potentially stabilizing atherosclerotic plaques, improving tolerance to a variety of stressors, and playing important roles in the development and maintenance of neural and retinal tissues and cognitive function.

In recent years, fish meal has been removed from some laboratory diets. Animal proteins generally cost significantly more than plant proteins; thus, pressure to decrease ingredient costs has driven the removal of animal-derived proteins from some formulations. Concern that fish meal is contaminated with mercury and nitrosamines has led some researchers to believe experimental results could be confounded by diets. However, as detailed below, fish meal and fish oil used in animal diet production contain very low levels of this metal or N-nitroso compounds. Further, research conducted in the last twenty years has proven that nearly any ingredient in a diet can potentially alter experimental results, depending upon the nature of the experiment and the ingredient; soybean meal and casein have been the most often cited protein sources shown to influence study outcomes.

Read the complete story from ALN.

 

 

 

 

 

 

 

KINGSTON, R.I. – November 4, 2010 – Two experimental commercial fishing nets for use in capturing squid have been tested by University of Rhode Island fisheries researchers, and preliminary data suggests that they were successful at reducing the capture of non-target species, also called by-catch.

“Squid is one of the most important fisheries in southern New England because the season is open all year, so fishermen can still catch it when other species are out of season or they’ve met their quotas on other fish,” said Barbara Somers, a researcher at the URI Fisheries Center.

By-catch is one of the most significant issues facing the commercial fishing industry. When non-target species are captured, it often must be discarded back into the ocean, and much of it is already dead.

So fishing net designer Jon Knight of Superior Trawl in Narragansett, in collaboration with commercial fishermen Chris Brown and Steve Arnold, developed the two new nets with adaptations that allow non-target species to escape.

One net incorporates a “rope escape panel” into its design that enables finfish like scup and butterfish, which are often found in the same waters as squid, to swim between the ropes and escape. The project was funded through the Commercial Fisheries Research Foundation of the Southern New England Collaborative Research Initiative.

The second net featured a 12-inch “drop chain” that created an opening beneath the mouth of the net that lets various species of flatfish avoid being captured. It was funded by a grant from the National Marine Fisheries Service to URI fisheries researchers Kathleen Castro, Laura Skrobe and Somers.

The URI researchers spent last spring and summer conducting tests of the new nets in side-by-side comparisons with traditional squid nets. The nets were also tested in a massive flume tank at Memorial University in Newfoundland. The data collected in the tests is still being analyzed, and outreach efforts to the fishing community will take place at the conclusion of the projects.

Preliminary results are promising. In a pilot study of the net designed to eliminate flatfish, the traditional net caught an average of 130 pounds of summer flounder while the redesigned net caught just 20 pounds of the overfished species.

“Both of these net designs will help fishermen reduce the catch of species they don’t want to target, thereby conserving the resource,” said Skrobe.

Read the complete press release from Media Newswire.

 

 

I congratulate Dr. Steve Murawski on the announcement of his new position as St. Petersburg Downtown Progress – Peter R. Betzer research professor at the University of South Florida’s College of Marine Science, which he will begin in January. 

I want to thank Dr. Murawski for his 35 years of outstanding service to our nation and NOAA’s Fisheries Service as a scientist and a leader.  As director of scientific programs and chief science advisor to the fisheries service for the last five years, Steve has overseen more than 25 laboratories, the use of more than nine offshore research vessels and the work of more than 2,000 staff throughout the United States. As chief scientist for the fisheries service, he and his staff have provided the scientific research necessary to guide management and conservation of our nation’s living marine resources and marine ecosystems. The science he and his staff provide is helping to protect and restore coastal and marine habitats, enhance populations of marine mammals and sea turtles, and rebuild fisheries that support vibrant coastal communities.

"I join with Eric Schwaab in thanking Dr. Murawski for his three and a half decades of service to NOAA’s Fisheries Service," said Dr. Jane Lubchenco, under secretary of commerce for oceans and atmosphere and NOAA administrator. “I want to particularly thank Steve for his tireless work in the last six months, helping NOAA and our nation respond effectively to the Deepwater Horizon oil spill, our nation’s worst marine oil spill. I have relied on Steve to provide NOAA and our nation with crucial scientific advice and leadership on a range of issues including seafood safety, the ecosystem effects of oil and the best ways to protect and recover protected species. I hope that we will continue to work with you, Steve, as you join the ranks of academia, but remain focused on our shared goal of better scientific understanding of our oceans."

NOAA is planning to conduct a national search to locate a suitable replacement for Dr. Murawski in the position of chief scientist for the fisheries service.

For more information contact Monica Allen, NOAA Fisheries Service Communications, at 301-713-2370 

 

 

 

 

 

 

 

The Commercial Fisheries Research Foundation (CFRF) has received funding under NOAA Award # NA10NMF4720480 for a pilot study to develop an up to date profile of the commercial fishing industry in Rhode Island, and is now in the process of accepting applications from prospective Project Research Teams interested in conducting the research. Click here for a copy of the project synopsis, along with a copy of the Request for Applications. (This information is also available on the CFRF’s website at www.cfrfoundation.org.)

The due date for applications is Tuesday, November 30, 2010 – 5:00 PM.  If you have any questions please feel free to contact me, and please feel free to pass this information along to others who might be interested.

Thank you for your interest.

 

 

 

 

 

 

 

 

NEW BEDFORD — The promise from U.S. Secretary of Commerce Gary Locke that he would consider revising catch limits for New England groundfishermen spurred Mayor Scott W. Lang's Ocean and Fisheries Council to furious activity over the past week.

A team of researchers, primarily from UMass Dartmouth's School of Marine Science and Technology, responded to the challenge and this week delivered a report offering a scientific basis for increasing annual catch limits. Their findings were presented at a mayor's council meeting Friday at the New Bedford Whaling Museum.

Steve Cadrin of SMAST explained that catch limits for each groundfish species are set below what is known as the ABC, or acceptable biological catch. The ABC, in turn, is set further below the "overfishing" limit. "The overfishing limit is estimated with uncertainty, so we're required to have a buffer, and for groundfish that buffer is 25 percent," Cadrin said, meaning fishermen can only target 75 percent of the allowable catch. Reducing that buffer, employing alternative methods to estimate the size of fish stocks and increasing the time line for rebuilding the stocks would all permit the catch limits to increase, according to the report.

Read the complete story from The South Coast Today.

 

 

 

 

 

A new study of the sea floor on Georges Bank may compel fishery managers to dramatically re-evaluate the measures currently employed to regulate the fishing industry there.

A submerged plateau warmed by the Gulf Stream, Georges Bank lies about 60 miles off Cape Cod. Its shallow waters, swept by nutrient-rich currents, provide rich feeding grounds for a wide variety of marine life, making it one of the world's most productive marine ecosystems.

Fishermen have worked these grounds for 400 years, resulting today in the closure of large areas, some of them permanently, to protect fish habitat and stocks. However, the map used to assess the impact of fishing on Georges Bank was compiled using just 190 sample points taken from the entire expanse of the bank, an area totaling more than 25,000 square miles.

Read the complete story from the South Coast Today.

Read the study in it's entirety.