Science

September 5, 2013 — A team of researchers from the University of Victoria embarks on a voyage today to further explore an expanding zone of low-oxygen water off Vancouver Island that threatens coastal fisheries and aquaculture.

The Schmidt Ocean Institute, which was created by Google’s chairman Eric Schmidt and his wife, Wendy, has offered the UVic team the use of its $62-million research vessel, Falkor, to further their research.

UVic’s Ocean Networks Canada already has a network of undersea sensors and instruments that relay data back to land over more than 850 kilometres of fibre-optic cable.

The hope is to combine that information with data gathered from the Falkor, which is equipped with acoustic sensors and an advanced sonar mapping system.

Researchers will then be able to track how low-oxygen water moves from the open ocean into the Strait of Georgia, Juan de Fuca Strait and other parts of the Salish Sea.

Read the full story from the Times Colonist

September 5, 2013 — A new study conducted by Dutch scientists in the North Sea suggests there may actually be some unexpected benefits from bottom trawling.

The report, entitled "When does fishing lead to more fish? Community consequences of bottom trawl fisheries in demersal food webs," was commissioned by the Wageningen Institute for Marine Resources and Ecosystem Studies (IMARES) in the Netherlands.

The findings were published Wednesday by the Royal Society in England.

Plaice and sole studied

The study focused on flatfish such as plaice and sole, and how those species — and their food — reacted to standard beam trawling.

Some of the results were surprising.

"What we found is that the indirect effects or side-effects of trawling — namely, the sort of selective removal of certain types of bottom life — sort of makes the system more productive in terms of food for the fish that fishermen target," said Tobias Van Kooten, one of three authors of the report, along with Daniel van Denderen and Adriaan Rijnsdorp.

The focus of the research was to model the effects of bottom trawling on fish species and food sources that are either resistant or susceptible to bottom trawling.

Read the full story at the CBC

View the study published in the Proceedings of the Royal Society B: Biological Sciences

Read an analysis of the study from Earth Times

 

Septmeber 4, 2013 — Next week, weather permitting, scientists from the University of Massachusetts’ Gloucester-based marine research center will head motor out to sea from Cape Cod in search of bluefin tuna.

They won’t be looking for the giant bluefin or the babies. They’ll be searching for the juvenile bluefins. For those juveniles, swimming in their middle schools, tagging season is about to begin.

The project, being coordinated by researchers and scientists at UMass’ Large Pelagics Research Center based in Gloucester’s Hodgkins Cove, will use the latest in electronic pop-up satellite tags to help develop enough data about these teenage tuna to potentially answer questions about migratory patterns, swimming depth, growth rate, breeding and the mixing of tuna from the western and eastern fishing grounds.

“We see this project having extraordinary value in terms of providing long-term data that could help us better understand these fish,” said Molly Lutcavage, the director and research professor at the local UMass facility. “It’s immensely important.”

The project is valuable on several fronts. While it is chiefly a data-gathering scientific enterprise, it also is a prime — and still rare — example of the scientific community and commercial fishermen working together.

“We have long-standing working relationships with a variety of captains and they’ve been invaluable,” Lutcavage said. “They helped develop the methods for landing and handling the fish. Throughout our history, we have a continuing record of working with the fishermen.”

The plan calls for the UMass scientists to leave Chatham on the Tammy Rose, captained by Eric Stewart at 4 a.m. Tuesday, with an expected return around 3 p.m. that day. The same schedule would apply for the following two days, as well.

The tagging process works like this: The tuna, generally 44-46 inches, is captured by rod and reel and brought aboard the boat. As soon as the fish hits the deck, the blur of activity ensues.

“The crew handles the fish, brings it aboard through the tuna door,” Lutcavage said. “We put it on a nice padded vinyl matt. We quickly cover the tuna’s eyes with a wet cloth so they don’t get stimulated and will calm down.”

Read the full story at the Gloucester Daily Times 

 

September 2, 2013 — Fishermen have traditionally been at odds with scientists and regulators. Too often, in their view, their livelihood has been threatened by regulations adopted in response to unreliable population assessments.

But instead of simply criticizing the science and fighting the regulations, the foundation is striving to play a role in better understanding fish populations. And with funding for government research typically on a tight budget, the foundation encourages tapping into the efforts and expertise of the people who are most often on the water and interacting with the resource: fishermen.

Thick fog obscures all but the lower towers of the Claiborne Pell Bridge as Al Eagles throttles down the Catherine Ann and drifts up to one of his pink buoys on this August morning.

He’s about to do what he’s been doing since he was 10 years old: pull on a line until a lobster trap sitting on the bottom is up on the gunwale with the day’s catch. Over the years, Eagles, 63, has gone from a 14-foot skiff and hand-hauled single wooden traps he fished as a boy to a 43-foot boat with a motorized winch to bring aboard sets of 20 plastic pots strung along trawl lines.

All in all, however, the technology hasn’t changed a great deal, which is why it’s curious to see Eagles pull out a tablet computer and digital calipers when deck hand Mark Clarke places the twitching lobsters out on a table to be measured.

Soon he is pressing buttons to enter information about each lobster he examines, even the ones he throws overboard because they’re below the minimum legal size. He records the size and gender of each one, while the tablet, aided by GPS, automatically notes the exact location and depth of the catch.

“I’m sort of computer illiterate,” Eagles readily admits. “I just started using a tablet just weeks before this started.”

It’s all in the name of science … and hopefully bountiful catches in the future.

Eagles is among a dozen New England fishermen who are voluntarily participating in a lobster survey begun by the Commercial Fisheries Research Foundation. The nonprofit group, based in Kingston and founded in 2004 by commercial fishermen, promotes a collaborative approach to fisheries research that involves fishermen.

Read the full story at the Providence Journal 

 

NEW BEDFORD, Mass., — September 2, 2013 — There's something wrong with the killifish in New Bedford Harbor. They should be dead.

Researchers at the Woods Hole Oceanographic Institution conducting a two-decade-long study of killifish say that the ones thriving in the harbor are contaminated with levels of polychlorinated biphenyls (PCBs) that are so high the fish "should not be able to survive."

"The fact that they are even there at all, that they are surviving in this highly polluted environment is remarkable," said Mark Hahn, a senior scientist at Woods Hole. "The amount of PCBs in their systems is higher than the lethal concentration for that species."

Killifish are prey fish that are usually just a few inches long. They can be found all over the world, but different populations stay in one place and do not migrate. They also reproduce frequently, making them ideal for researching how fish adapt to their environments.

When Hahn and his team began examining New Bedford's killifish in 1995 as part of a Superfund study program, the first thing they looked at was the fishes' enzyme levels.

When healthy killifish from fresh water are exposed to high levels of PCBs, their bodies create an enzyme to help break down the toxins and allow them to survive. When the enzyme is overloaded with the chemical, the fish die because they can no longer process the dose.

The researchers expected that killifish living in Superfund Sites would have high levels of the enzyme to help stave off the toxin.

But New Bedford's killifish do not.

"As we looked into it, we realized that the enzyme level was low because the fish had evolved a tolerance to PCBs," Hahn said.

Hahn said he believes the New Bedford killifish had become resistant to the effects of PCBs decades before his study started. Their resistance may have evolved starting in the 1940s, when industries began dumping PCBs into the Acushnet River.

Read the full story at the New Bedford Standard-Times 

 

August 31, 2013 — BOSTON (AP) — Scientists this month completed a pilot project to measure the health of flatfish species off New England that relied heavily on the expertise of fishermen, right down to using their trawlers.

The survey comes amid intense criticism of traditional scientific methods for counting fish.

Fish sampling surveys provide critical data for assessing the health of fish populations, which are at the core of fishing rules. Critics say the assessments have proven to be deeply flawed and it’s wrong to use them as the basis for setting the struggling industry’s catch limits.

Scientists say their overall methods are sound, but they acknowledge some consistent problems.

“We can learn, and we do want to build confidence and be responsive,” said Bill Karp, the Northeast’s chief federal fisheries scientist.

Read the full story from the Associated Press at CBS Boston

August 27, 2013 — Nova Scotia scientists believe they have located the breeding ground for the endangered North Atlantic right whale in the Gulf of Maine.

The research increases the chances of survival for the species, says conservation biologist Tim Frasier of Saint Mary’s University in Halifax.

"The mating ground is particularly important," said Frasier from his DNA analysis laboratory. "If you want to conserve a species the main animals you want to protect are the ones that are reproducing."

Scientists believe the population of the ponderous mammals has dwindled to fewer than 500.

In recent years, the whales have been killed by entanglement in fishing gear, or by being hit by passing ships.

Read the full story from CBC News

August 28, 2013 — The following was released by NOAA Fisheries:

Intense interest in the Georges Bank yellowtail flounder stock is one driver behind a just-completed pilot research survey.  Two commercial trawlers, F/V Mary K and F/V Yankee Pride, worked about 175 stations over 12 days. The survey was coordinated and funded by NOAA Fisheries' Northeast Fisheries Science Center, and designed by a panel that included researchers, fishermen, and gear manufacturers.

Chief scientist Michael Martin of the NEFSC said the operations went well. “We were able to complete a very intensive survey of Georges Bank in a very short time thanks to the dedicated efforts of the captains, crews, and scientists aboard,” said Martin.

Once data are audited for quality, the NEFSC will release an informal report for this cruise as it does for all Center resource surveys.  The report is expected by early October.

By conducting this pilot survey, the NEFSC hopes to get a better idea of how an industry-based, dedicated survey for flatfish could augment other data collection in the region, and the resources required to establish and maintain such a survey.

Both the United States and Canada routinely cover Georges Bank during large-scale standardized research surveys for multiple species; however, none of these is specifically focused on flatfish like yellowtail flounder. Species-specific surveys such as this one can often reveal more about that species’ condition and help to better interpret data from the broad-scale survey.

“A directed industry-based flatfish research survey could certainly provide data useful in making baseline population estimates for Georges Bank yellowtail and winter flounder and help us monitor population changes in the future,” said Martin.

Information on the distribution, sizes, and ages of fish collected on the survey could provide some immediate insights into population condition. If the pilot survey evolves into an permanent, regular survey, results can be used to identify trends in Georges Bank flatfish abundance and biomass.  

The pilot survey used a modified version of a survey net built by Superior Trawl for an industry-based survey of southern New England yellowtail flounder conducted between 2003 and 2005.

The net is a two-seam, two-bridle flounder net with a 118- foot cookie sweep. Two modifications were made to the 2003-2005 survey net: the twine in the lower wings and first belly was reduced, and a codend liner was installed.  Both of these modifications are intended to improve the capture of smaller flounder, ensuring that even very small fish –the youngest in the population—would be represented in survey catches.

The pilot survey targeted areas of Georges Bank that were expected to have high flatfish concentrations.  The bank was divided into “high abundance” and “low abundance” areas based on input from fisherman. Stations were randomly selected within those areas, with numbers of stations heavily weighted towards high abundance zones. As on other resource surveys, the scientific party also collected biological samples.

Operations were conducted both day and night in depths of about 25 to 60 fathoms. The fishing vessel operators strove for consistency in tow time and speed and in setting and retrieving the net.  This helped to minimize the effects of net operation on catch rates, since the goal was to collect a consistent sample rather than to catch as many fish as possible, as would usually happen on a commercial trip.

Read the story from NOAA Fisheries

PORTLAND, OR. — August 29, 2013 — The Pacific Ocean off the Oregon Coast is really loud. That’s the finding of scientists working for Oregon State University, NOAA and the federal Energy Department.

For the past year, they’ve been listening to sounds picked up by a hydrophone sunk in about 50 meters of water, just off Newport.  What they’ve recorded is a vigorous symphony of natural and man-made noises.

Read the full story and listen to the audio from Oregon Public Broadcasting

August 25, 2013 — Mercury — a common industrial toxin — is carried through the atmosphere before settling on the ocean and entering the marine food web. Now, exciting new research from the University of Michigan and the University of Hawai'i at Manoa School of Ocean and Earth Science and Technology (SOEST) combines biogeochemistry and direct marine ecology observations to show how the global mercury cycle is colliding with ocean fish — and the human seafood supply — at different depths in the water.

Mercury accumulation in the ocean fish we eat tends to take place at deeper depths, scientists found, in part because of photochemical reactions that break down organic mercury in well-lit surface waters. More of this accessible organic mercury is also being generated in deeper waters.

"A few years ago we published work that showed that predatory fish that feed at deeper depths in the open ocean, like opah and swordfish, have higher mercury concentrations than those that feed in waters near the surface, like mahi-mahi and yellowfin tuna," said Brian Popp, professor of geology and geophysics at UH Manoa, and a co-author of a new paper scheduled for online publication August 25 in the scientific journal Nature Geoscience. "We knew this was true, but we didn't know why."

"We knew that organic and inorganic mercury dissolved in seawater has a nutrient-like profile, with lower concentrations at the surface and higher concentrations at depth," said Anela Choy, a PhD candidate in oceanography at UH Manoa. "We saw it in the water, and we saw it in the fish. But we couldn't explain the gradient we saw, nor did we know exactly where and how the bioavailable organic mercury was entering the marine food web."

Bacteria in the oceans change atmospheric mercury into the organic monomethylmercury form that can accumulate in animal tissue. Large predatory fish contain high levels of methylmercury in part because they eat lots of smaller, mercury-containing fish. In 2009, researchers at UH Manoa determined that the depths at which a species feeds is nearly as important as its position in the food chain in determining how much methylmercury it contains.

Read the full story at e! Science News