Archive for the Research Category

Mar 12 2018

West Coast waters returning to normal but salmon catches lagging

Fish school around a drill rig off Southern California. A new report says West Coast waters are returning to normal after warm temperatures shook up the food web. Credit: Adam Obaza/West Coast Region/NOAA Fisheries

Ocean conditions off most of the U.S. West Coast are returning roughly to average, after an extreme marine heat wave from about 2014 to 2016 disrupted the California Current Ecosystem and shifted many species beyond their traditional range, according to a new report from NOAA Fisheries’ two marine laboratories on the West Coast. Some warm waters remain off the Pacific Northwest, however.

The Southwest Fisheries Science Center and Northwest Fisheries Science Center presented their annual “California Current Ecosystem Status Report” to the Pacific Fishery Management Council at the Council’s meeting in Rohnert Park, Calif., on Friday, March 9. The California Current encompasses the entire West Coast marine ecosystem, and the report informs the Council about and trends in the ecosystem that may affect marine species and fishing in the coming year.

“The report gives us an important glimpse at what the science is saying about the species and resources that we manage and rely on in terms of our West Coast economy,” said Phil Anderson of Westport, Wash., the Council Chair. “The point is that we want to be as informed as we can be when we make decisions that affect those species, and this report helps us do that.”

Unusually warm temperatures, referred to as “the Blob,” encompassed much of the West Coast beginning about 2014, combining with an especially strong El Nino pattern in 2015. The warm conditions have now waned, although some after-effects remain.

Salmon catches off the West Coast are likely to remain low in the next few years, until new generations of salmon can benefit from improving conditions Credit: NOAA Fisheries/West Coast Region

  • Feeding conditions have improved for California sea lions and seabirds that experienced mass die-offs caused by shifts in their prey during the Blob.
  • Plankton species, the foundation of the marine food web, have shifted back slightly toward fat-rich, cool-water species that improve the growth and survival of and other fish.
  • Recent research surveys have found fewer , and consequently adult salmon returns will likely remain depressed for a few years until successive generations benefit from improving ocean conditions.
  • Reports of whale entanglements in fishing gear have remained very high for the fourth straight year, as whales followed prey to inshore areas and ran into fishing gear such as pots and traps.
  • Severe low-oxygen conditions in the ocean water spanned the Oregon Coast from July to September 2017, causing die-offs of crabs and other species.

Even as the effects of the Blob and El Nino dissipate, the central and southern parts of the West Coast face low snow pack and potential drought in 2018 that could put salmon at continued risk as they migrate back up rivers to spawn.

“Overall we’re seeing some positive signs, as the ocean returns to a cooler and generally more productive state,” said Toby Garfield, a research scientist and Acting Director of the Southwest Fisheries Science Center. “We’re fortunate that we have the data from previous years to help us understand what the trends are, and how that matters to West Coast fishermen and communities.”

NOAA Fisheries’ scientists compile the California Current Ecosystem Status Report from ocean surveys and other monitoring efforts along the West Coast. The tracking revealed “a climate system still in transition in 2017,” as surface ocean conditions return to near normal. Deeper water remained unusually warm, especially in the northern part of the California Current. Warm-water species, such as leaner plankton often associated with subtropical waters, have lingered in these more-northern zones.

Feeding conditions for California sea lions have improved off the West Coast, following several lean years that led to unusually high losses of sea lion pups. Credit: Sharon Melin/Alaska Fisheries Science Center/NOAA Fisheries

 

One of the largest and most extensive low-oxygen zones ever recorded off the West Coast prevailed off the Oregon Coast last summer, probably driven by low-oxygen water upwelled from the deep ocean, the report said.

While the cooling conditions off the West Coast began to support more cold-water plankton rich in the fatty acids that salmon need to grow, salmon may need more time to show the benefits, the report said. Juvenile salmon sampled off the Northwest Coast in 2017 were especially small and scarce, suggesting that poor feeding conditions off the Columbia River Estuary may remain.

Juvenile salmon that enter the ocean this year amid the gradually improving conditions will not return from the ocean to spawn in the Columbia and other rivers for another two years or more, so fishermen should not expect adult salmon numbers to improve much until then.

“These changes occur gradually, and the effects appear only with time,” said Chris Harvey, a fisheries biologist at the Northwest Fisheries Science Center and coauthor of the . “The advantage of doing this monitoring and watching these indicators is that we can get a sense of what is likely to happen in the ecosystem and how that is likely to affect communities and economies that are closely tied to these waters.”


Originally posted: https://phys.org/news/2018-03-west-coast-salmon-lagging.html

Nov 25 2017

Pacific Council Gives Preliminary Nod to Two Coastal Sardine and Other Pelagic Species Projects

November 22, 2017 — SEAFOOD NEWS — The Pacific Fishery Management Council last week approved for public review two exempted fishing permits that should help improve coastal pelagic species stock assessments.

Both projects would add more survey work to nearshore areas. Fishermen have identified schools of sardines, in particular, close to shore but accessing them for survey work has been a problem because the sardine season has been closed and NOAA ships cannot access shallow areas. Additionally, both proposals would build on the use of industry knowledge.

The California Wetfish Producers Association research project intends to sample CPS schools in the southern California Bight using aerial spotter pilots with camera systems to fly surveys close to shore and photo-document schools. At the same time, qualified purse seine vessels would capture a subset of the schools identified in the photographs as “point sets.” This would provide a way to address issues identified in the aerial survey methodology review. The survey period is scheduled for late August 2018.

According to the CWPA application, all fish captured, including sardines, would be processed and sold by participating processors, and fishermen will be paid for their catches at the usual rates. Aside from the sale of fish, processors would not be compensated for the extra labor they will incur in weighing and fully sorting each school individually and documenting species composition by school, rather than the normal procedure of offloading the entire catch and documenting by load.

“We strongly support these EFP projects to improve the accuracy of stock assessments. It should be noted that 70 percent or more of the CPS harvest in California occurs in the area inshore of NOAA acoustic surveys,” CWPA Executive Director Diane Pleschner-Steele said. “We are grateful to the California Department of Fish and Wildlife and Southwest Fishery Science Center for their help and recognition that surveying the nearshore is a high priority research and data need.”

Pacific Seafood’s Mike Okoniewski presented the Westport, Wash.-based West Coast Pelagic Conservation Group project to both the Council and the Scientific and Statistical Committee. The project is designed to provide supplementary data collection and additional sampling techniques for areas nearshore of the proposed 2018 NOAA/Southwest Fisheries Science Center acoustic-trawl survey, according to the group’s application. This research off of Washington and Oregon would continue and expand the 2017 collaborative effort in 2018 so that samples of CPS for species composition and individual fish metrics may be obtained through purse seine operations, according to Council documents.

Sampling would be done at the same general time and nearshore areas as the NOAA survey, the applicants stated. The coastal pelagic species (CPS) that will be retained in small amounts (e.g. 5kg to 25kg) for sampling will be dip-netted sardines, anchovies, and mackerel(s). The sample fish will be frozen and retained for identification and biological measurements to be performed by NOAA.

But unlike the southern EFP, no fish will be harvested for commercial purposes. Wrapped schools would be released alive, the applicants said.

“This collaboration will continue to support the already commendable efforts of the scientists, balancing it with industry knowledge of the fishing grounds,” Okoniewski said.

Both EFPs will add to current survey and stock assessment work, providing more robust data for the fisheries in the future. The Council’s Scientific and Statistical Committee and Coastal Pelagics Species Management Team supported the EFPs and suggested minor technical changes to each; both applicants plan to incorporate those suggestions prior to the Council’s and NMFS’ final approval in early 2018.

“The CPSMT recognizes the value of the EFP research proposed by both groups to improve CPS stock assessments by obtaining data that has not been attainable by other means,” the CPS Management Team said in its statement.

The Coastal Pelagic Species Advisory Subpanel also supported the projects. “[We are] encouraged that forward progress is now being made to develop effective survey methods for the nearshore area,” the panel said in its statement. “The CPSAS thanks CWPA, WCPCG and especially the SWFSC for acknowledging the data gaps in current surveys and helping to provide support and funding for cooperative surveys that will hopefully improve the accuracy of future CPS stock assessments.”


This story originally appeared on Seafoodnews.com, a subscription site. It is reprinted with permission.

Oct 31 2017

‘Rule of Thumb’ Management Approach Is Wrong For Forage Fish, Dr. Ray Hilborn Tells U.S. Senate

Saving Seafood interviews Dr. Ray Hilborn about forage fish management ahead of his testimony before the Senate Commerce Subcommittee on Oceans, Atmosphere, Fisheries and Coast Guard.

 

WASHINGTON (Saving Seafood) – October 31, 2017 – At a hearing of the U.S. Senate Commerce Subcommittee on Oceans, Atmosphere, Fisheries and Coast Guard last week, respected fisheries scientist Dr. Ray Hilborn testified that fisheries managers “can do better than a one-size-fits-all” approach to managing forage fish. He also said there was “no empirical evidence to support the idea that the abundance of forage fish affects their predators.”

Dr. Hilborn’s comments came in response to questioning from Sen. Roger Wicker (R-MS) about whether fisheries managers should manage forage fish according to a “rule of thumb” approach, where fisheries are managed according to a set of broad ecological and management principals, or a “case-by-case” approach, where management is guided by more species-specific information.

Dr. Hilborn, a professor at the University of Washington’s School of Aquatic and Fishery Sciences, was part of a team of top fisheries scientists that recently examined these issues, as well as what effects fishing for forage fish species had on predator species. Their research indicated that previous studies, like a 2012 report from the Lenfest Forage Fish Task Force, may have overestimated the strength of the predator-prey relationship.

Before the hearing, Dr. Hilborn spoke with Saving Seafood about his research and his message for lawmakers.

“It’s very clear that there really are no applicable rules of thumb, that every system is independent [and] behaves differently, and we need to have the rules for each individual forage fish fishery determined by looking at the specifics of that case,” Dr. Hilborn told Saving Seafood.

He also discussed his team’s finding that forage fish abundance has little impact on their predators. They looked at nearly all U.S. forage fish fisheries, including the California Current system and Atlantic menhaden, and concluded that predator species generally pursue other food sources when the abundance of any one forage species is low.

“The predators seem to go up or down largely independent of the abundance of forage fish,” Dr. Hilborn said, adding, “For Atlantic menhaden, for their major predators, the fishery has reasonably little impact on the food that’s available to them.”

Another key message Dr. Hilborn had for the Subcommittee was that fisheries managers must determine what they want to accomplish so that scientists can advise them accordingly.

“The time has come to refocus our fisheries policy on what we actually want to achieve because rebuilding is only a means to an end,” Dr. Hilborn told Saving Seafood. “Do we want to maximize the economic value of our fisheries? Do we want to maximize jobs? Do we want to maximize food production?”

In his testimony, Dr. Hilborn praised U.S. fisheries policy that has “led to rebuilding of fish stocks and some of the most successful fisheries in the world.” He attributed this success to a variety of factors, including funding of NOAA, regionalizing fisheries management decisions, and requiring managers to follow science advice. As a result, overfishing should no longer be the top priority for fisheries managers, he testified.

“The major threats to U.S. fish stock and marine ecosystem biodiversity are now ocean acidification, warming temperatures, degraded coastal habitats, exotic species, land based run off, and pollution,” Dr. Hilborn testified. “Overfishing remains a concern for a limited number of stocks but should not continue to be the most important concern for U.S. federal fisheries policy.”

The hearing was the latest in a series examining reauthorization of the Magnuson-Stevens Fishery Conservation and Management Act, the nation’s supreme fisheries law. It was organized by subcommittee chairman Sen. Dan Sullivan (R-AK), and focused on fisheries science.


Originally posted: Saving Seafood Inc.

Oct 25 2017

Testimony of Ray Hilborn to U.S. Senate subcommittee

Testimony of Ray Hilborn to U.S. Senate subcommittee.

 


 

Subcommittee to Continue Hearing Series on Magnuson-Stevens Act

WASHINGTON – U.S. Sen. Dan Sullivan (R-Alaska), chairman of the Subcommittee on Oceans, Atmosphere, Fisheries, and Coast Guard, will convene the hearing titled “Reauthorization of the Magnuson-Stevens Fishery Conservation and Management Act: Fisheries Science,” at 2:30 p.m. on Tuesday, October 24, 2017. The hearing is the fourth of the series and will focus on the state of our nation’s fisheries and the science that supports sustainable management.

Witnesses:

– Mr. Karl Haflinger, Founder and President, Sea State, Inc
– Dr. Ray Hilborn, Professor, University of Washington School of Aquatic and Fishery Sciences
– Dr. Michael Jones, Professor, Michigan State University Quantitative Fisheries Center
– Dr. Larry McKinney, Director, Texas A&M University Harte Research Institute for Gulf of Mexico Studies

Hearing Details:

Tuesday, October 24, 2017
2:30 p.m.
Subcommittee on Oceans, Atmosphere, Fisheries and Coast Guard

This hearing will take place in Russell Senate Office Building, Room 253. Witness testimony, opening statements, and a live video of the hearing will be available on www.commerce.senate.gov.

Oct 23 2017

Professor has a message for Congress: Overfishing is over

Rob Hotakainen, E&E News reporter
Published: Monday, October 23, 2017
Ray Hilborn. Photo credit: University of Washington

Fisheries scientist Ray Hilborn. University of Washington

 

To his detractors, fisheries professor Ray Hilborn is an “overfishing denier,” a scientist who’s all too eager to accept money from industry groups to pay for his pro-fishing research.

To his backers, he’s a hero, a respected researcher who can always be counted on to challenge environmental groups that want to limit fishing.

Love him or hate him, there’s little doubt that the outspoken Hilborn has attained an international profile and that he has found a way to win big-time attention in fishing circles.

His next stop is Capitol Hill.

Tomorrow, Hilborn, a professor of aquatic and fishery sciences at the University of Washington, will appear before a Senate Commerce, Science and Transportation panel, getting another chance to argue his case that overfishing is no longer a concern for the United States.

He’s one of four experts scheduled to testify before the Subcommittee on Oceans, Atmosphere, Fisheries and Coast Guard.

“What I’m going to say in my testimony is that overfishing is no longer the major threat to the sustainability of our oceans or biodiversity,” Hilborn said in an interview. “My first line on Tuesday is going to be that we have really fixed our fisheries by having fisheries management follow science advice — and if you stop doing that, you’re in trouble.”

Hilborn also said it’s time to stop “vilifying” fishing.

“I wrote the book on overfishing, called ‘Overfishing: What Everyone Needs to Know,’ by Oxford University Press,” Hilborn said. “You know, overfishing is a serious problem in many places. It’s not a very serious problem in the United States now. It was 30 years ago. … And the U.S. has responded, as has Europe. In most developed countries, fish stocks are increasing in abundance, they are not declining in abundance.”

The question of overfishing is a key focus for Congress as lawmakers consider making changes to the Magnuson-Stevens Fishery Conservation and Management Act, a law passed in 1976 that sets the rules for fishing in federal waters (E&E Daily, July 17).

Backers and opponents alike credit the landmark law for improving the health of U.S. fish stocks, though many worry the Trump administration has moved too quickly to allow more fishing.

Commerce Secretary Wilbur Ross, who oversees NOAA, heightened those concerns with two key decisions: In June, he extended the season for the Gulf red snapper by 39 days, and in July, he overturned a decision by the Atlantic States Marine Fisheries Commission that would have cut New Jersey’s recreational quota for summer flounder, also known as fluke (Greenwire, Sept. 20).

Critics fear Ross’ decisions could lead to overfishing and jeopardize both fish stocks in the long run.

Meanwhile, the president’s fisheries chief, Chris Oliver, told a House Natural Resources panel last month that 91 percent of all fishing stocks assessed by NOAA are no longer subject to overfishing.

Oliver, the head of NOAA Fisheries, told the Subcommittee on Water, Power and Oceans that the U.S. had “effectively ended overfishing,” allowing “room for flexibility” in applying annual catch limits (E&E Daily, Sept. 27).

Those are fighting words for many conservationists who worry the Trump team has already gone overboard in bowing to the demands of fishing groups.

“When they talk about flexibility, they’re really talking about rollbacks,” said John Hocevar, a marine biologist and ocean campaigns director for Greenpeace USA.
An ideal spokesman?

Hilborn has plenty of fans, but he has faced accusations of industry bias.

Last year, he won the International Fisheries Science Prize at the World Fisheries Congress in Busan, South Korea, recognized for a 40-year-career of “highly diversified research” on behalf of global fisheries science and conservation.

“There aren’t many fisheries scientists in the country who can match Ray Hilborn,” said Noah Oppenheim, executive director of the Pacific Coast Federation of Fishermen’s Associations. “He’s the ideal spokesman for his field to educate Congress about how science informs fisheries management. Anyone who questions Ray’s professional or scientific integrity doesn’t understand how science works, at best.”

But a study by Greenpeace last year found that Hilborn accepted more than $3.55 million from 69 commercial fishing and seafood interests to pay for his research from 2003 to 2015.

“It seems like he uses his genuine scientific credentials to make himself more valuable to industry as a spokesperson,” said Hocevar. “On climate denial, there are a bunch of those guys. But with fisheries, Hilborn is the guy. … He’s the go-to, and there’s really no one else out there like him who will come out and talk about how we don’t need marine protected areas and how the real problem is underfishing, not overfishing.”

Greenpeace gained access to University of Washington documents that showed Hilborn’s long and extensive links to fishing, seafood and other corporate groups by filing a request under the state’s public records law.

After Greenpeace complained that Hilborn had not properly disclosed his affiliations in all his published papers, the university investigated the issue and concluded Hilborn had not violated any of its policies.

But Hocevar said the issue is still relevant.

“He took millions of dollars from industry. … And studies have shown that where you get your funding from does create bias in terms of findings,” Hocevar said.

Hilborn dismissed the criticism from Greenpeace.

“You know, they’re hopeless fundamentally,” he said. “They’re basically a money-raising organization, and they have to scare people to raise money. They’re not interested in science at all. … Greenpeace has sort of put its cards on the table that fishing is a big deal, and they’re not going to raise money if people don’t believe that fishing is a threat.”

Schedule: The hearing is Tuesday, Oct. 24, at 2:30 p.m. in 253 Russell.

Witnesses: Karl Haflinger, founder and president, Sea State Inc.; Ray Hilborn, professor, University of Washington School of Aquatic and Fishery Sciences; Michael Jones, professor, Michigan State University Quantitative Fisheries Center; and Larry McKinney, director, Texas A&M University Harte Research Institute for Gulf of Mexico Studies.


Originally published: E&E Daily

Oct 7 2017

Coastal Researchers, Fishermen Worried About More Frequent Low Oxygen Zones

Olympic Coast National Marine Sanctuary research team members, Kathy Hough and LTJG Alisha Friel, recover sensors deployed seasonally off the coast of Washington from the research vessel Tatoosh in July 2017. — S. Maenner / NOAA

 

Scientists in Oregon and Washington are noticing a disruptive ocean phenomenon is becoming more frequent and extreme. It involves a suffocating ribbon of low oxygen seawater over our continental shelf.

The technical term is hypoxia, sometimes called “dead zones,” It’s an unwelcome variation on normal upwelling of cold, nutrient rich water from the deep ocean. When the dissolved oxygen drops too low, it drives away fish and can suffocate bottom dwellers such as crabs and sea worms who can’t scurry away fast enough.

It seemed to marine ecologist Francis Chan like this is happening most every summer lately. So the Oregon State University researcher looked back as far as coastal oxygen readings go—to about 1950—to see if it’s always been this way.

“The ocean starting in 2000 really looked different from the ocean we had between the 1950s and 1990s,” Chan said.

Chan said climate change could affect oxygen levels via disrupted circulation and ocean warming. 
 A September storm flushed away this year’s low oxygen zone by churning Northwest coastal waters. But Chan described the severity of the low oxygen readings recorded this summer as among the worst ever observed locally.

“It’s very much a patchy ribbon,” he said from his post in Newport, Oregon. Marine surveys and fixed instruments recorded notably low oxygen values from south of Yachats up past Newport.

Ten oceanographic moorings deployed by the Olympic Coast National Marine Sanctuary also found very low (hypoxic) oxygen values between Cape Elizabeth and Cape Flattery, Washington, this summer.

“This is not a happy year for organisms out on the coast,” said Jenny Waddell, the marine sanctuary’s research coordinator.

Waddell added that at least one sensor dipped into anoxic conditions, “where there’s literally no oxygen.”

“We had indications of a relatively persistent hypoxia event along the Quinault Reservation coastline,” wrote marine scientist Joe Schumacker of the Quinault Department of Fisheries in an email Friday. “Dead fish and shellfish at various locations and times beginning near the end of July and extending through most of August.”

More frequent and severe near-shore hypoxia concerns fishermen and crabbers. Commercial harvesters face reduced catches and economic losses when crabs suffocate and fish and prawns flee the oxygen-starved waters.

One of the tip-offs to OSU researchers of the onset of low oxygen conditions this summer was when Oregon Department of Fish and Wildlife biologists monitoring crab populations noticed crabs dying from lack of oxygen in a research trap. Other observers noted crabs leaving the ocean to seek more oxygenated waters in coastal estuaries and bays.

Earlier this year, researchers and fishery advocates found a receptive ear at the Oregon Legislature when they presented their concerns about silent changes in the ocean. Legislators approved the creation of a new council to be co-chaired by the state Fish and Wildlife director and an OSU leader.

The council is tasked with recommending and coordinating a long-term strategy to address hypoxia as well as ocean acidification.


Originally published: http://nwnewsnetwork.org/

Oct 4 2017

What scientists are learning about the impact of an acidifying ocean

The effects of ocean acidification on marine life have only become widely recognized in the past decade. Now researchers are rapidly expanding the scope of investigations into what falling pH means for ocean ecosystems.

The ocean is becoming increasingly acidic as climate change accelerates and scientists are ramping up investigations into the impact on marine life and ecosystems. In just a few years, the young field of ocean acidification research has expanded rapidly – progressing from short-term experiments on single species to complex, long-term studies that encompass interactions across interdependent species.

“Like any discipline, it takes it time to mature, and now we’re seeing that maturing process,” said Shallin Busch, who studies ocean acidification at the National Oceanic and Atmospheric Administration’s (NOAA) Northwest Fisheries Science Center in Seattle.

As the ocean absorbs carbon dioxide from the burning of fossil fuels, the pH of seawater falls. The resulting increase in acidity hinders the ability of coral, crabs, oysters, clams and other marine animals to form shells and skeletons made of calcium carbonate. While the greenhouse gas effect from pumping carbon dioxide into the atmosphere has been known for decades, it wasn’t until the mid-2000s that the impacts of ocean acidification became widely recognized. In fact, there is no mention of acidification in the first three reports from the United Nations Intergovernmental Panel on Climate Change, issued in 1990, 1995 and 2001. Ocean acidification did receive a brief mention in the 2007 report summarizing the then-current state of climate science, and finally was discussed at length in the latest edition released in 2014.

But about halfway through that brief dozen years of acidification research, a shift started taking place.

“The early studies were just a first step and often quite simple,” said Busch of ocean acidification research. “But you can’t jump into the deep end before you learn how to swim.”

That started to change about five or six years ago, according to Philip Munday, who researches acidification effects on coral reefs at Australia’s James Cook University. “The first studies were often single species tested against ocean acidification conditions, often quite extreme conditions over short periods of time,” he said. “Now people are working on co-occurring stresses in longer-term experiments.”

That includes studying how acidification could change how organisms across a community or ecosystem interact – in other words, how the impacts on one species affect those it eats, competes with or that eat it. It also means looking at how impacts could change over time, due to species migrating or adapting, either in the short term or across a number of generations and how such effects may vary within the same species or even with the same population.

Nine examples of this new generation of acidification research are included in the latest issue of the journal Biology Letters. One study, for example, found that the ability to adapt to pH changes differed in members of the same species of sea urchins based on location. Another discovered that a predatory cone snail was more active in waters with elevated carbon dioxide levels but was less successful at capturing prey, reducing predation on a conch species. Another highlights that an individual organism’s sex can affect its response to acidification.

Munday, who edited the series of papers, said one of the major takeaways is that researchers are increasingly studying the potential for species to adapt to ocean acidification and finding those adaptations can be quite complex.

He pointed to a study on oysters. Previous work had shown that oysters whose parents were exposed to acidification conditions do better in those conditions than those whose parents weren’t. But in a new study, researchers found that when they exposed the offspring to additional stressors – such as hotter water temperatures and higher salinity – those adaptive advantages decreased.

All the studies call for including often-overlooked factors such as sex, location or changes in predation rate in future studies. Otherwise, researchers warn, impacts will be increasingly difficult to predict as the ocean continues to acidify.

“It’s far too early to make any sort of generalities,” Munday said.

The latest paper from NOAA’s Busch also cautions against generalities. By building a database of species in Puget Sound and their sensitivity to changes in dissolved calcium carbonate, she found that summarizing species’ sensitivity by class or order rather than the specific family can result in overestimating their sensitivity.

She compared it to similarities between people in the same immediate family versus people who are distant cousins. “There would be a lot more variation among those people because they’re not super closely related,” she said. “But when people started summarizing data really early in the field, there wasn’t much data to pull from. So it was done at a class level.

“Now that we have many more studies and information to pull from, how we draw summaries of species response should be nuanced,” she added.

Acidification research is likely to get only more nuanced in the years ahead. From the broad initial projections of average, ocean-wide surface acidity, for instance, researchers have started to pinpoint local pH projections, local impacts and local adaptations.

“We know the ocean is changing in a number of ways,” said Busch. “So just studying one of those factors without looking at the other changes in what’s going on in the ocean is not going to yield useful results.”

Matthew O. Berger, NewsDeeply, 2 October 2017. Article.


Originally published: https://news-oceanacidification-icc.org/

Sep 21 2017

Authors of Recent Research on Forage Fish Respond to Criticism from Lenfest Task Force

WASHINGTON – September 20, 2017 – In April, a team of respected fisheries scientists led by Dr. Ray Hilborn published a study that found fishing of forage species likely has a lower impact on predators than previously thought. This conclusion challenged previous forage fish research, most notably the 2012 Lenfest Oceans Program report “Little Fish, Big Impact,” which recommended leaving more forage fish in the water to be eaten by predators. 

The Lenfest task force responded to this new research with a Letter to the Editor of Fisheries Research, where the Hilborn et al. study was published. In response to this letter, Hilborn et al. wrote their own letter, which was published August 5 in Fisheries Research and is reproduced below:

Our paper highlighted that key biological relationships between forage fish and their predators were not included in the models used in the LENFEST report. These missing elements were (1) the high level of natural variability of forage fish, (2) the weak relationship between forage fish spawning stock size and recruitment and the role of environmental productivity regimes, (3) the size distribution of forage fish, their predators and subsequent size selective predation and (4) the changes in spatial distribution of the forage fish as it influences the reproductive success of predators. We demonstrate that each of these elements can have a major impact on how one evaluates the impact of fishing forage species on their predators. The LENFEST report used EwE models without these factors to determine the very specific recommendations they made about how to manage forage fish.

We certainly agree that in some cases fishing forage fish will affect their predators, but in other cases there may be little if any impact – it all depends on the biology that was not included in the models used.

This critique of our paper suggests that we are offering alternative evaluation of the impact of fishing forage fish that are, like the LENFEST recommendations, broadly applicable. We make no such claim and much of their critique is against the straw man they have constructed. We are not arguing that fishing forage fish does not affect predators. Rather we show how, in specific cases, there may be little if any impact of fishing forage fish and that general conclusions simply are not possible.

We suggest that the very specific quantitative measures proposed in the LENFEST report result from models that do not have these components and that if these elements were included in the models the conclusions would likely be different. While the authors of the letter argue that they conducted a comprehensive literature review, the specific recommendations came from their modelling, and it is the modelling we criticize and their critique makes few attempts to defend.

We stated “Pikitch et al. (2012) argued forcefully that their analysis provided general conclusions that should be broadly applied. However, relevant factors are missing from the analysis contained in their work…” Their response is that their recommendations were “tailored to the level of uncertainty and data availability of each system.” What we refer as “general conclusions” contain a set of recommendations for three uncertainty tiers, but our point is that the biology of each system is different, not the availability of data or uncertainty, and the differences in biology should be considered when evaluating management options for forage fisheries.

The specificity of their recommendations is clear – for high information situations (which would include the California Current, Humboldt Current, NE Atlantic sand eel and herring) their recommendation is “In any case, lower biomass limits should not be less than 0.3 B0, an MAX F should not exceed 0.75 FMSY or 0.75 M.” These numbers are not the result of their case studies or literature review but the result of their models that did not include a number of important elements.

Finally, we agree that situations where detailed information is lacking are challenging for management, and that is why it is important to identify species and system attributes that make systems less resilient to fishing. Low trophic level species constitute the largest potential sources of increased fish production in the world and much of the recent suggestions for “balanced harvesting” relies on significant increases in exploitation rates on trophic levels associated with forage fish. Since almost all of these potential low trophic level species would be considered in the “low information tier” the LENFEST recommendation is that new fisheries not be allowed until sufficient data are collected. Given that few countries will devote resources to research on fisheries that do not exist, the LENFEST recommendation essentially says no new fisheries on these species, and thus in effect precludes development of what may be significant food resources.

We believe the authors of our paper and the LENFEST report all accept that in some cases predators may be highly dependent on forage fish, but in other cases there may be little dependence. Management should be based upon what is known about the dependence of the predators on forage fish and the relative importance the local agencies place on maintaining high predator abundance verses the benefits of full exploitation of the forage fish. The major forage fisheries of the world are very valuable and currently intensively studied. What is needed for each of these fisheries is a new set of models that incorporate the elements that were missing from the LENFEST analysis.

Ray Hilborn, Ricardo O. Amoroso, Eugenia Bogazzi, Olaf P. Jensen, Ana M. Parma, Cody Szuwalski, Carl J. Walters

Sep 6 2017

Study negates concerns regarding radioactivity in migratory seafood

Study negates concerns regarding radioactivity in migratory seafood Assistant professor Kevin Weng of the Virginia Institute of Marine Science with a dolphinfish or mahi-mahi (Coryphaena hippurus) collected as part of the study of Fukushima-derived radioactivity in large Pacific Ocean predators. Credit: A. Gray aboard FV Aoshibi IV.



When the Fukushima power plant released large quantities of radioactive materials into nearby coastal waters following Japan’s massive 2011 earthquake and tsunami, it raised concerns as to whether eating contaminated seafood might impair human health—not just locally but across the Pacific.

A new study by an international research team shows that those concerns can now be laid to rest, at least for consumption of meat from migratory marine predators such as tuna, swordfish, and sharks.

The team focused on cesium, a silvery metal with a large number of radioactive isotopes. Two of these, 134Cs and 137Cs, form when uranium fuel breaks down in nuclear reactors. The cesium isotopes are of particular concern because they were discharged in large quantities following the disaster, exhibit relatively long half-lives (2.1 and 30 years respectively), and tend to accumulate in the muscle tissues that people like to eat.

However, the team’s sampling of tissues from predatory fishes and other large vertebrates collected across the northern Pacific between 2012 and 2015 revealed no detectable levels of 134Cs, and 137Cs concentrations that were generally consistent with background levels from aboveground nuclear testing during the 1940s and 50s. They collected the animals from waters near Japan, Hawaii, and California.

Lead author Daniel Madigan of Harvard University says, “Our measurements and associated calculations of how much radioactive cesium a person would ingest by eating this seafood shows that impacts to human health are likely to be negligible. For marketed fish to be restricted from trade, the cesium levels would have to be more than 1,600 times higher than in any samples we measured.”

Co-author Kevin Weng, an assistant professor at William & Mary’s Virginia Institute of Marine Science, participated in the study by collecting fish samples in waters around Oahu and a remote seamount. He says, “Go ahead and eat some sushi! Our work shows that radioactivity from the Fukushima disaster is very low in open-ocean vertebrates.”

Study negates concerns regarding radioactivity in migratory seafood Assistant professor Kevin Weng of the Virginia Institute of Marine Science with a bigeye tuna (Thunnus obesus) collected as part of the study of Fukushima-derived radioactivity in large Pacific Ocean predators. Credit: A. Gray aboard FV Aoshibi IV.



Also contributing to the study were Zofia Baumann and Nicholas Fisher of Stony Brook University; Owyn Snodgrass, Heidi Dewar, and Peter Dutton of NOAA’s Southwest Fisheries Science Center; Michelle Berman-Kowalewski of the Channel Islands Cetacean Research Unit; and Jun Nishikawa of Tokai University.

The researchers undertook their analysis partly in response to earlier studies by Madigan and colleagues showing elevated levels of radioactive cesium in bluefin and albacore tuna caught off the California coast shortly after the Fukushima disaster—evidence that these fishes had swum almost 6,000 miles in less than two months. (It took ocean currents more than two years to deliver much-diluted cesium from Fukushima to those same waters.)

Although this early work focused on the utility of cesium isotopes as a happenchance tool that could help scientists characterize migratory patterns among a group of heavily exploited commercial fishes, public attention focused on perceived risks to human health.

“The earlier studies showed extremely low risks from cesium to anyone eating these migratory species, but public concern persisted,” says Weng. That concern also expanded to include not only the species of tuna in which cesium had been measured, but to other fishes, marine mammals, and sharks.

“People were very concerned about North Pacific salmon, halibut and scallops off British Columbia, and sea lions in Southern California,” says Madigan. “There was even information on the Internet that ‘the Pacific is dead’.”

“One goal of our study,” he says, “was to put these perceived risks in context by surveying a broad range of vertebrate species across the entire North Pacific for the presence or absence of Fukushima-derived radiocesium. Our results, which show very low or undetectable levels in these animals, are important both for public perception of seafood safety and for scientific understanding of radionuclide transfer.”

The authors suggest that scientists and funding agencies should look for at least one silver lining in any future nuclear or industrial accidents. “We can and should use future point sources of contamination, radioactive or otherwise, to shed new light on migratory dynamics of pelagic species that are poorly understood, heavily exploited, or of high conservation concern,” says Madigan. “But we would need to act quickly, within that narrow opportunistic timespan.”


Originally posted: https://phys.org/news/2017-08-negates-radioactivity-migratory-seafood.html

Aug 15 2017

Fishermen See ‘Science in Action’ Aboard NOAA Survey Ship

 

Each spring and early summer, scientists set out along the West Coast aboard NOAA vessel Reuben Lasker to survey coastal pelagic species, or CPS, which includes small schooling fish such as northern anchovy, Pacific sardine, and jack and Pacific mackerels.

This year, with the help of West Coast fishermen, the scientists tested a new approach to extend their reach into nearshore waters to improve the accuracy of the survey results. The collaboration involved the fishing vessel Lisa Marie, of Gig Harbor, Washington, and brought two commercial fishermen aboard Lasker for an inside look at NOAA Fisheries surveys that inform stock assessments and guide decisions on how many fish can be caught by West Coast fishermen.

The idea emerged years before when the then-Director of NOAA’s Southwest Fisheries Science Center in La Jolla, California,  Cisco Werner, along with Deputy Director Kristen Koch and Fisheries Resources Division Director Gerard DiNardo, discussed the potential collaboration with Mike Okoniewski of Pacific Seafood and Diane Pleschner-Steele of the California Wetfish Producers Association.

Werner has since been named Chief Scientist of NOAA Fisheries.

The Magnuson-Stevens Fishery Conservation and Management Act requires NOAA Fisheries to use the best available science to help managers set catch limits and prevent overfishing. Annual surveys, using echosounders to detect and measure the abundances of CPS populations off the coasts of California, Oregon, Washington, and Canada’s Vancouver Island help fulfill this mandate. NOAA Fisheries also uses trawl catches, and fish-egg samples to help gauge fish reproduction and population trends.

“Acoustic-trawl surveys are our principal tool for monitoring the various species and determining how their abundances, distributions, and sizes are changing,” said David Demer, the Chief Scientist of the survey and leader of the Advanced Survey Technologies Group at Southwest Fisheries Science Center in La Jolla. “The surveys are very rigorous because they’re very important to our mission.”

To quantify any CPS in the shallow, nearshore waters off Oregon and Washington where Lasker cannot survey, Demer’s group equipped Lisa Marie, calibrated the instrumentation, and sailed with the fishermen to collect and analyze echosounder and sonar data along coastal transects.

Meanwhile Andy Blair, fisherman and owner of Lisa Marie, and Greg Shaughnessy, Chief Operating Officer of Ocean Gold Seafoods in Westport, Washington, spent five days aboard Lasker, learning how NOAA Fisheries scientists collect information that informs NOAA Fisheries stock assessments and leads to CPS harvest decisions by the Pacific Fishery Management Council.

“I learned a lot, even though I’ve been out fishing for years,” said Shaughnessy. “Now that I’ve been out there and seen how the work is done, I have a much better understanding of the logistics involved and how thorough and rigorous the work really is.”

A spotter pilot flew overhead during parts of the survey looking for and photographing schools of fish from above. The digital images will augment the measurements made aboard Lasker and Lisa Marie.

The vessels and aircraft confirmed each other’s findings when concurrently surveying the same areas.

Okoniewski praised NOAA Fisheries for welcoming commercial fishermen aboard Lasker and explaining the survey methods and science.

“We’ve really opened some new doors with this collaboration,” said Okoniewski, who with Shaughnessy and Blair are members of West Coast Pelagic Conservation Group, a non-profit advocacy and conservation group that represents commercial fishermen and processors. “There’s now a much greater understanding of what we each do and how we do it. It’s kind of a new age in terms of how we see each other.”

Sardine fishing is currently closed off the West Coast because sardine numbers, which are known for boom-bust cycles, have fallen below a protective threshold in a rule that governs harvest. Surveys are essential in determining when the cycle reverses, the population rebounds and, in turn, when fishing for sardines can resume.

“It was a wonderful chance to see science in action,” Shaughnessy wrote in a letter to SWFSC leadership. “From a fisherman’s perspective, the array of acoustic and scientific equipment itself is stunning. However, it was the dedicated men and women that made the real difference. Every crew member was very professional in every sense and yet made us feel included, safe, and at home.”

NOAA Fisheries Reuben Lasker
NOAA Fisheries Vessel Reuben Lasker uses echosounders, sonars, and a trawl net to survey populations of sardine, anchovy, and mackerels. (Photo credit: NOAA Fisheries) 

Lisa Marie resizedFishing Vessel Lisa Marie, based out of Westport, Washington, uses a purse-seine net to fish for sardine and other small fish. (Captain: Ricky Blair; owner: Andy Blair; photo credit: NOAA Fisheries/Scott Mau)

CPS Schools aerial view resizedCPS schools (dark patches) in shallow, nearshore water off Washington, and a ship, imaged from an aircraft. (Photo credit: Frank Foode)

Echogram of fish schools 2017 resizedEchogram of fish schools (red patches), one near the sea-surface (top of the image), and multiple others deeper. Also visible are plankton (blue layers), individual fish (discrete blue spots), the seabed (jagged red line), and 50- and 100-m depth markers (dotted lines). (Image credit: NOAA Fisheries/Scott Mau)


Read the original post: https://swfsc.noaa.gov/news.aspx?ParentMenuId=39&id=22667