New methods further discern extreme fluctuations in forage fish populations

Anchovy, sardine, and hake scale deposition rate from AD 1000 − 1500 derived from a recent, age-calibrated sediment core from Santa Barbara Basin, California. Representative fish scales and the respective fishes are shown on the right. Image credit: I.L. Hendy, University of Michigan; S. McClatchie, NOAA Fisheries; NMFS image library

ANN ARBOR—California sardine stocks famously crashed in John Steinbeck’s “Cannery Row.” New research, building on previous since the late 1960s, shows in greater detail that such forage fish stocks have undergone boom-bust cycles for centuries, with at least three species off the U.S. West Coast repeatedly experiencing steep population increases followed by declines long before commercial fishing began.

Natural population fluctuations in Pacific sardine, northern anchovy and Pacific hake off California have been so common that the species were in collapsed condition 29 to 40 percent of the time over the 500-year period from A.D. 1000 to 1500, according to the study published online Feb. 9 in Geophysical Research Letters.

Using a long time series of fish scales deposited in low-oxygen, offshore sedimentary environments off Southern California, researchers from the National Oceanic and Atmospheric Administration and the University of Michigan described such collapses as “an intrinsic property of some forage fish populations that should be expected, just as droughts are expected in an arid climate.”

The findings have implications for the ecosystem, as well as fishermen and fisheries managers, who have witnessed several booms, followed by crashes every one to two decades on average and lasting a decade or more, the scientists wrote. Collapses in forage fish—small fish that are preyed on by larger predators for food—can reverberate through the marine food web, causing prey limitation among predators such as sea lions and sea birds.

“Forage fish populations are resilient over the long term, which is how they come back from such steep collapses over and over again,” said Sam McClatchie, supervisory oceanographer at NOAA Fisheries’ Southwest Fisheries Science Center in La Jolla, Calif., and first author of the paper.

“That doesn’t change the fact that these species may remain at very low levels for periods long enough to have very real consequences for the people and wildlife who count on them,” he said.

Downturns in sardine and anchovy linked to changing ocean conditions have contributed to the localized stranding of thousands of California sea lion pups in recent years.

Former University of Michigan graduate student Karla Knudsen, left, and former U-M undergraduate Athena Eyster sample deep-sea sediment collected in 2009 with a coring device beneath the Santa Barbara Channel in California. The sediments were used in a fish-scale analysis. Image credit: Ingrid Hendy

Scientists traced the historic abundance of sardine, anchovy and hake by examining deposits of their scales collected on the floor of the Santa Barbara Channel from A.D. 1000 to 1500. While previous studies had shown that forage fish exhibited collapses prior to commercial fishing, the new research used methods developed by climatologists to examine the frequency and duration of the fluctuation in finer detail.

“The Mediterranean climate of California, with wet winters and dry summers, produces a sediment layer we can pull apart like pages in a book,” said U-M paleoceanographer and study co-author Ingrid Hendy. “Although these sediments have been studied before, we are using new technology to examine them in unprecedented detail.”

Hendy and members of her lab collected the California sediments in 2009 using a coring device that allowed them to sample large portions of the sea floor beneath the Santa Barbara Channel. Hendy is an associate professor in the U-M Department of Earth and Environmental Sciences.

In the lab, fish scales from the core were identified under a binocular dissecting microscope by comparing them to reference specimens from the U-M Museum of Zoology collection. Anchovies in the collection were bought at the San Pedro Fish Market, near Long Beach, Calif., in 1922. The sardines came from Barkley Sound, on the west coast of Vancouver Island, and were collected in 1933.

From left to right: Former University of Michigan undergraduate Athena Eyster, former U-M graduate student Karla Knudsen, Ingrid Hendy and former U-M graduate student Meghan Wagner examine a sediment core collected in the Santa Barbara Channel, California, in 2009. Image credit: Arndt Schimmelmann

The fish-scale analysis was performed by former U-M undergraduate Alexandra Skrivanek, who is now a graduate student at the University of Florida. Hendy’s lab has also helped to advance techniques used to date the layers within marine sediment cores. Those advances involve improved radiocarbon dating of organic materials in the sediments and better ways to count the annual layers, Hendy said.

The scientists described a collapse as a drop below 10 percent of the average peak in fish populations, as estimated from the paleorecord. Anchovy took an average of eight years to recover from a collapse, while sardine and hake took an average of 22 years.

The record also showed that sardine and anchovy fluctuated synchronously over the 500-year study period. Combined collapses may compound the impact on predators and the fishery, the scientists said. The finding runs counter to suggestions that the two species’ cycles alternate.

Sardine and anchovy have at times been the most heavily harvested fish off Southern California in terms of volume. Hake, also known as Pacific whiting, spawn off California but are harvested in large volumes off the Pacific Northwest and Canada.

The new study concludes these forage fish are well-suited to variable fishing rates that target the species in times of abundance, “while recognizing that mean persistence of fishable populations is one to two decades, and that switching to other target species will become a necessity.”

Collapses last, on average, “too long for the industry to simply wait out the return of the forage fish.”

The study authors concluded that “well-designed reserve thresholds” and adjustable harvest rates help protect the forage species, the fishery and nonhuman predators for the long term. However, they added that “reserve thresholds only protect the seed stock for recovery, and cannot prevent collapses from occurring.”

Funding for the study was provided by NOAA and the National Science Foundation.

Read the original post: http://www.ns.umich.edu/

Omega 3 Health Benefits, Nutrition Facts And Sources

October 31st, 2016 — According to a lot of research, omega 3 benefits each of the body’s systems in its own way. The greatest benefits can be found in the heart and the brain.

In places where other fats clog the arteries and contribute to heart disease, the omega 3 fatty acids helps to fight off the heart disease in many ways.

Here I have contributed a list of the things that omega 3 can do for your heart:

• Anti-Coagulant Activity – helps prevent the formation of clots in the blood
• Antioxidant Activity – they help to prevent oxidation of the fats that are found in the bloodstream. When the fats become oxidized, they can stick to the artery walls and harden atherosclerosis
• Relax Smooth Muscles – the help reduce the blood pressure, which can reduce the risk of stroke and heart attack
• Improves The Levels Of Cholesterol – Cholesterol isn’t all bad. Most individuals who have problems with cholesterol have high levels of LDL and low levels of HDL. The particles of LDL are most
• likely to stick to the walls of the arteries and create clots. HDL is what helps remove the particles of LDL from the blood. Omega 3 supplements have been known to increase the amount of HDL.
• Lowers The Amount of Blood Triglycerides – triglycerides are the fats found in the blood. The more fats that are found in your blood, the more likely you are to develop blood clots, have a stroke, or develop heart disease. The prescription medication LOVAX used for high levels of triglycerides is really nothing but omega 3 fish oil
• Anti-Inflammatory Activity – when the oxidized fats get stuck to the artery walls, they create swelling or inflammation, which makes the arteries even narrower

Read the full report at Cooking Detective 

Read the original post: http://www.savingseafood.org/

Fish oil turns fat-storage cells into fat-burning cells in mice, study finds

Photo: Neil Tackaberry/Flickr

Fish oil has long been known to confer a wide range of health benefits, including boosting the cardiovascular system and potentially even treating the effects of schizophrenia. Now a new study from Japan says it could also help people trying to lose weight.

Researchers from Kyoto University found that mice fed on fatty food and fish oil gained considerably less weight and fat than mice that consumed fatty food alone. The findings suggest that fish oil is able to transform fat-storage cells into fat-burning cells – and if the same process occurs in humans, fish oil could help us reduce weight gain, especially as we age, when our fat-burning cells are in lesser supply.

While we might think of our fat tissue as primarily a fat storage system, this isn’t always so. White fat cells store fat, but brown fat cells metabolise fat to maintain a stable body temperature. Our bodies metabolise fat more easily when we’re young, as we have a greater amount of brown fat cells in youth, but we start to lose them in maturity.

Scientists have also discovered a third type of fat cell – beige fat cells – which function much like brown fat cells in mice and people. Also like brown fat cells, the beige cells diminish in number as we get older, making it harder for our bodies to burn fat. This is where fish oil could come into play.

“We knew from previous research that fish oil has tremendous health benefits, including the prevention of fat accumulation,” said food scientist Teruo Kawada from Kyoto University. “We tested whether fish oil and an increase in beige cells could be related.”

To examine the links, the researchers fed one group of mice fatty food, and another group fatty food with fish oil additives. The results, published in Scientific Reports, reveal how the animals that consumed the food with fish oil gained less 5 to 10 percent less weight and 15 to 25 percent less fat – a significant reduction in the circumstances.

But why does this happen? The researchers say that fish oil activates receptors in the digestive tract, which fires up the sympathetic nervous system and induces storage cells to metabolise fat. In other words, the fish oil causes white cells to transform into beige cells, effectively turning fat-storage tissue into fat-metabolising tissue and leading to increased energy expenditure at the expense of weight gain and fat accumulation. This is good to know.

It’s too soon to say whether these findings also apply to humans, but further studies may show just that, which the researchers believe could contribute to an effective treatment for obesity.

“People have long said that food from Japan and the Mediterranean contribute to longevity, but why these cuisines are beneficial was up for debate,” said Kawada. “Now we have better insight into why that may be.”

Read the original post: http://www.sciencealert.com/

‘Ridiculously Resilient Ridge’ retires, making room for rain

El Niño is expected to bring a low-pressure system, which will replace the high-pressure system that’s exacerbated California’s drought. nasa.gov

The high pressure system that has shunted storms away from California for much of the past four years has dissipated, possibly for a long time.

The Ridiculously Resilient Ridge — as meteorologists and forecasters have dubbed the system because of its unusual persistence — has been absent for more than a month, according to a forecaster with the National Oceanic and Atmospheric Administration.

“It hasn’t been like that since August really, and instead we’ve had sort of more variable weather patterns,” said Nate Mantua, a research scientist with NOAA’s Southwest Fisheries Science Center in Santa Cruz.

Mantua said the ridge will likely stay away, because it will have been replaced by a low-pressure trough.

“The expectations are as we get into Fall and Winter seasons more deeply, we’re going to see a lot more low pressure there, and that will be the more sort of dominant story,” Mantua said.

Eric Boldt, a meteorologist with the National Weather Service in Oxnard, said low-pressure systems typically accompany El Niño events.

“Lower pressure in the Eastern Pacific is a classic pattern you’d see with an El Niño setting up with the jet stream a little more to the south, and that’s were we get into our storm track coming up from the southwest across California,” Boldt said.

The high-pressure ridge has created a large swath of unusually warm water off the coast. Boldt said the warm water would take months to dissipate and that its interaction with El Niño isn’t well understood. However, he said storms from strong El Niño events, which can bring heavy rains to California, could be bolstered by the warm water.

“That’s the part that is a little bit unprecedented. We don’t really have a good idea about how that might impact us, but warmer ocean temperatures typically lead to fueling the atmosphere and kind of energizing those storms. So I don’t think it’s going to be a negative for us,” Boldt said.

Mantua said the disappearance of the ridge and the presence of a strong El Niño is likely to produce a lot of rain in Southern California.

“[The low-pressure system is] just another factor that sort of favors a more normal winter, although I don’t think it’s going to be normal. I think it’s going to be probably an exciting winter, especially for Southern California,” Mantua said.

Read/listen to the original post: http://www.scpr.org/

Researchers Keep Missing Picture on Sardines, Where there is a 1400 Year History of Boom and Bust

— Posted with permission of SEAFOODNEWS.COM. Please do not republish without their permission. —

Copyright © 2015 Seafoodnews.com

“Climate variations or natural boom-and-bust cycles contribute to population fluctuation in small fast-growing fish, ” Pinsky said, “but when they are not overfished, our data showed that their populations didn’t have any more tendency to collapse than other fish. ” He called these findings counterintuitive because the opposite dynamic holds true on land: “Mice thrive while lions, tigers and elephants are endangered, ” he said.

While it’s common these days to blame the ocean’s woes on overfishing, the truth is Pinsky’s conclusions don’t paint a complete picture. Fortunately, we do have an accurate picture and it’s definitely better than the proverbial thousand words.

The picture is a graph (adapted from Baumgartner et al in CalCOFI Reports 1992, attached) that shows sardine booms and busts for the past 1,400 years. The data were extracted from an anaerobic trench in the Santa Barbara Channel which correlated sardine and anchovy recoveries and collapses with oceanic cycles.

(Click on Image for larger Version)

It’s important to note that most of sardine collapses in this timeframe occurred when there was virtually no commercial fishing. The best science now attributes great fluctuations and collapses experienced by sardines to be part of a natural cycle.

“Pinsky has never been a terrestrial biologist or naturalist or he would have known that small rodents have boom and bust cycles brought about by combinations of environmental conditions and the mice’s early maturity and high fecundity rates, ” says Dr. Richard Parrish, an expert in population dynamics now retired from the National Marine Fisheries Service, .

“All fish stocks show boom and bust cycles in recruitment unrelated to fishing, ” says Dr. Ray Hilborn, internationally respected fisheries scientist from the University of Washington. “Sardines in particular have been shown to have very great fluctuations and collapses long before commercial fishing. Fast growing, short-lived species will be much more likely to decline to a level called “collapse” when recruitment fluctuates because they are short lived — longer lived species won’t decline as much. ”

As a further poke in the eye to the truth, Pinsky cites sardines off the coast of Southern California as a species that has seen fluctuations for thousands of years, but “not at the levels that they’ve experienced in recent decades due to overfishing. ”

Again, this simply is not true.

Since the fishery reopened in 1987, Pacific sardines have been perhaps the best-managed fishery in the world – the poster fish for effective ecosystem-based management. The current harvest control rule, updated to be even more precautionary in 2014, sets a strict harvest guideline that considers ocean conditions and automatically reduces the catch limit as the biomass declines.

If the temperature is cold – which scientists believe hampers sardine recruitment – the harvest is reduced. And if the population size declines, both the harvest rate and the allowable catch will automatically decrease, and directed fishing will be stopped entirely when biomass declines below 150,000 mt.

In fact, the current sardine harvest rule is actually more precautionary than the original rule it replaced. It does this by producing an average long-term population size at 75 percent of the unfished size, leaving even more fish in the water, vs. 67 percent in the original rule. The original harvest rule reduced the minimum harvest rate to 5 percent during cold periods. The present has a minimum rate of 0 percent during cold periods.

Compare this to the 1940s and ’50s when the fishery harvest averaged 43 percent or more of the standing sardine stock with little regulatory oversight and no limit on the annual catch. This, coupled with unfavorable ocean conditions, culminated in the historic sardine fishery collapse that devastated Monterey’s Cannery Row.

But that was nearly 70 years ago, not “recent decades. ” Our current fishery harvest is less than a quarter of the rate observed during that historical sardine collapse.

As a scientist, Pinsky should be aware of the complex, proactive management efforts that have been in place for decades to prevent overfishing in California and the west coast. He should also be aware of the data from Baumgartner that contradicts his faulty conclusions.

D. B. Pleschner is executive director of the California Wetfish Producers Association, a nonprofit dedicated to research and to promote sustainable Wetfish resources.

Copyright © 2015 Seafoodnews.com

Global Fisheries Scientists set up ‘Truth Squad’ to Counter Inaccurate Scientific Claims in Media

— Posted with permission of SEAFOODNEWS.COM. Please do not republish without their permission. —

Copyright © 2015 Seafoodnews.com

Their media partners lap up stories of doom and collapse, often uncritically.  For that reason, a group of  International experts in fisheries management have come together as part of a new initiative, called CFOOD (Collaborative for Food from Our Oceans Data.) The coalition will gather data from around the world and maintain fisheries databases while ensuring seafood sustainability discussions in the media reflect ground-truth science.

The scientists behind the project have long pushed for accurate and clean data sources on the world’s fisheries.

The CFOOD project, headquartered at the University of Washington’s School of Aquatic and Fishery Sciences (SAFS), is made up of a network of scientists whose mission stemmed from a frustration with erroneous and agenda-driven stories about fisheries sustainability in the media. The CFOOD project will maintain a website and social media channels that provide a forum for immediate feedback on new seafood sustainability reports and studies.

“The CFOOD website allows us to offer independent scientific commentary to debunk false claims, support responsible science, or introduce new issues based on recent research,” said Dr. Ray Hilborn, Professor at University of Washington’s SAFS and founder of the CFOOD initiative.

“The ocean is a remarkably abundant source of healthy protein,” said Hilborn. “And while sustainability challenges exist, particularly in areas lacking sufficient fishery management infrastructure, many fisheries around the world are well-managed and sustainable. The message doesn’t always seem to resonate with consumers because of misinformation they continue to hear in the media.”

By reviewing and providing scientific analysis on relevant studies, papers, and media reports the CFOOD network hopes to use science to set the record straight for consumers, so they can have confidence the seafood they purchase is harvested in an environmentally responsible fashion.

Other scientists on the editorial board for CFOOD include Robert Arlinghaus, Leibniz-Institute of Freshwater Ecology and Inland Fisheries and Humboldt at Universität zu Berlin; Kevern Cochrane, FAO Retired, Cape Town, South Africa; Stephen Hall, World Fish Center, Penang, Malaysia; Olaf Jensen, Rutgers University; Michel Kaiser, Bangor University, UK; Ana Parma, CONICET Puerto Madryn, Argentina; Tony Smith, Hobart, Australia; Nobuyuki Yagi, Tokyo University.

“Exaggerated claims of impending ecological disaster might grab attention, but they risk distorting effort and resources away from more critical issues.  I hope this initiative will help provide the balance we need,” said Dr. Stephen Hall, Director General, World Fish Center, based in Malaysia.

The first set of comments on the CFOOD website debunks a WWF paper claiming a 74% decline in global mackerel and tuna species.  The scientists point out that the data used to support that conclusion is out of date, having not been updated since 2004, and that more robust data sources, such as the actual stock assessments of tuna and mackerel stocks around the world were not used by the WWF in creating their estimate.  We explore the comments in depth in our related story.

To connect with the scientists, you can use twitter, facebook, or their website.

Website:  Twitter:  Facebook:

John Sackton, Editor and Publisher

Copyright © 2015 Seafoodnews.com

Ray Hilborn Says Recent Science Paper Makes Inflated Claim about Human Impacts on Marine Species

— Posted with permission of SEAFOODNEWS.COM. Please do not republish without their permission. —

Copyright © 2015 Seafoodnews.com

Ray says the authors made a mistake in only looking at individual predators and in not considering all predation on a given species.  He says that when all predation is considered, the results reverse themselves, and that natural predators take a larger proportion of adult marine fish than humans do.

His comment is below:

Comment by Ray Hilborn, University of Washington

This paper claims that humans have a up to 14 times higher exploitation rate than natural predators. There is a basic flaw in the analysis which diminishes the validity of the conclusions the authors come to. First the calculated predation rate of natural predators will depend on how many predators you look at. Dozens or even hundreds of species may prey upon a given species, most of them taking a trivial fraction of the prey. If you find data only for the most important predators (the ones that take the most of the prey species) you will estimate a high predation rate, but if you find data for all the species that prey upon a species the median will be much much lower.

In fact there are hundreds of potential predators for any species, most take none of the prey species, so if you had data for all of them you would say that the average predation rate was nearly zero for natural predators. Thus the more data on predation rate for individual species you can find, and the more you find predation data for trivial predators, the lower you will estimate “average” predation. However, if you look at the predators who take the most of the specific prey the fraction of the prey will be much higher and often more than humans.

The more important question is what is the total predation rate compared to the human exploitation rate? One has to read the Darimont paper carefully to realize they are talking about rates of individual predatory species, not rates of predators as a whole. For instance their abstract says “humans kill adult prey… at much higher median rates than other predators (up to 14 times higher). ” Thus they are comparing the rates of all other predatory species taken one at a time to that of humans. There may be natural predators who have a very high predation rate (higher than humans), but they are masked by the average of other predators with low rates. The clear implication is that we take more adults than do predators. Much of the media coverage interprets their results this way.

This is absolutely not true as shown in the analysis below which shows that humans take about ½ as many adult fish as marine predators.

Chart: Ray Hilborn

To compare the rates of fishing mortality to rates of natural mortality (almost all of which is from predation), I used the RAM Legacy Stock Assessment Data Base (www.ramlegacy.org) the same data base used by Dairmont et al. to obtain fishing mortality rates. I selected the 223 fish stocks for which we had both natural mortality and human exploitation rates, and plot the distribution of the two in the graph below. We find that fishing mortality on adult fish is on average roughly ½ of the predation rate — not 14 times higher as the abstract of their paper would leave you to believe. Remember Dairmont were not looking at all of predation, but counting each predator as an individual data point. In aggregate predators take far more adult fish than do humans, but you would not understand that by reading the Dairmont paper.

The authors conclude that argument that globally humans are unsustainable predators. This flies in the face of the fact that we have considerable empirical evidence that we can sustainably harvest fish and wildlife populations. The basic key to sustainable harvesting is keeping the fraction exploited at a level that can be sustained in the long term, and adjusting harvest up and down as populations fluctuate. The Food and Agriculture Organization of the United Nations provides the most comprehensive analysis of the status of global fisheries and estimates than about 30% of global fish stocks are overexploited – the other 70% are at levels of abundance that are generally considered sustainable.

Many fisheries are evaluated by independent organizations like the Marine Stewardship Council and Monterey Bay Aquarium and classified as “sustainable” yet Dairmont and co-authors suggest that no fisheries are sustainably managed.

As an example, sockeye salmon in Bristol Bay Alaska have been sustainably managed for over a century, have been evaluated as sustainable by every independent organization, and the key is limiting harvest so that enough fish reach the spawning grounds to replenish the species. In this case humans take about 2/3 of the returning adult salmon – a much higher fraction than the predators, but it is sustainable and stocks are at record abundance.

Darimont and coauthors suggest we need to reduce exploitation pressure by as much as 10 fold. This may be true in some places but in the US we manage fisheries quite successfully. We agree with the authors that management is key to keeping healthy and sustainable populations of fish and wildlife. However, instead of “emulating natural predators” and decreasing human exploitation across the board, we need to work to use our knowledge to expand good management practices to more species and areas of the world.

Letters: Grossman Article on Reasons for Sardine Decline Inaccurate

— Posted with permission of SEAFOODNEWS.COM. Please do not republish without their permission. —

SEAFOODNEWS.COM [Letters] – June 23, 2015

Editor’s Note: The following letter from D.B. Pleschner was reviewed and supported by Mike Okoniewski of Pacific Seafoods.

To the Editor: I take exception to your statement:  “The author of this piece, Elizabeth Grossman, buys into the argument, but in a fair article.”

In no way was this “fair” reporting.   She selectively quotes (essentially misquotes) both Mike Okoniewski and me (and this after I spent more than an hour with her on the phone, and shared with her the statements of Ray Hilborn, assessment author Kevin Hill and other noted scientists.) She does not balance the article but rather fails to emphasize the NOAA best science in favor of the Demer-Zwolinski paper, published in NAS by NOAA scientists who did not follow protocol for internal review before submitting to NAS (which would have caught many misstatements before they saw print).

NOAA’s Alec MacCall later printed a clarification (in essence a rebuttal) in NAS, which pointed out the errors and stated that the conclusions in the Demer paper were “one man’s opinion”.

Oceana especially has widely touted that paper, notwithstanding the fact that the SWFSC Center Director also needed to testify before the PFMC twice, stating that the paper’s findings did not represent NOAA’s scientific thinking.

After the Oceana brouhaha following the sardine fishery closure, NOAA Assistant Administrator Eileen Sobeck issued a statement. SWFSC Director Cisco Werner wrote to us in response to our request to submit Eileen’s statement to the Yale and Food & Environment Reporting Network to set the record straight:

“The statement from the NMFS Assistant Administrator (Eileen Sobeck) was clear about what the agency’s best science has put forward regarding the decline in the Pacific Sardine population. Namely, without continued successful recruitment, the population of any spp. will decline – irrespective of imposed management strategies.”

It is also  important to note that we are working closely with the SWFSC and have worked collaboratively whenever possible.

I would greatly appreciate it if you would again post Sobeck’s statement to counter the inaccurate implications and misstatements in  Elizabeth Grossman’s piece.

Diane Pleschner-Steele
California Wet Fish Producers Association

PS:   I also informed Elizabeth Grossman when we talked that our coastal waters are now teeming with both sardines and anchovy, which the scientific surveys have been unable to document  because the research ships survey offshore and the fish are inshore.

Sobeck’s statement follows:

Researchers, Managers, and Industry Saw This Coming: Boom-Bust Cycle Is Not a New Scenario for Pacific Sardines
A Message from Eileen Sobeck, Head of NOAA Fisheries
Apri 23, 2015

Pacific sardines have a long and storied history in the United States. These pint-size powerhouses of the ocean have been — on and off — one of our most abundant fisheries. They support the larger ecosystem as a food source for other marine creatures, and they support a valuable commercial fishery.

When conditions are good, this small, highly productive species multiplies quickly. It can also decline sharply at other times, even in the absence of fishing. So it is known for wide swings in its population.

Recently, NOAA Fisheries and the Pacific Fishery Management Council received scientific information as a part of the ongoing study and annual assessment of this species. This information showed the sardine population had continued to decline.

It was not a surprise. Scientists, the Council, NOAA, and the industry were all aware of the downward trend over the past several years and have been following it carefully. Last week, the Council urged us to close the directed fishery on sardines for the 2015 fishing season.  NOAA Fisheries is also closing the fishery now for the remainder of the current fishing season to ensure the quota is not exceeded.

While these closures affect the fishing community, they also provide an example of our effective, dynamic fishery management process in action. Sardine fisheries management is designed around the natural variability of the species and its role in the ecosystem as forage for other species. It is driven by science and data, and catch levels are set far below levels needed to prevent overfishing.

In addition, a precautionary measure is built into sardine management to stop directed fishing when the population falls below 150,000 metric tons. The 2015 stock assessment resulted in a population estimate of 97,000 metric tons, below the fishing cutoff, thereby triggering the Council action.

The sardine population is presently not overfished and overfishing is not occurring. However, the continued lack of recruitment of young fish into the stock in the past few years would have decreased the population, even without fishing pressure. So, these closures were a “controlled landing”. We saw where this stock was heading several years ago and everyone was monitoring the situation closely.

This decline is a part of the natural cycle in the marine environment. And if there is a new piece to this puzzle — such as climate change — we will continue to work closely with our partners in the scientific and management communities, the industry, and fishermen to address it.

Read/Download Elizabeth Grossman’s article: Some Scientists and NGO’s Argue West Coast Sardine Closure was too Late

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Toxic algae bloom might be largest ever

 

Scientists onboard a NOAA research vessel are beginning a survey of what could be the largest toxic algae bloom ever recorded off the West Coast.

A team of federal biologists set out from Oregon Monday to survey what could be the largest toxic algae bloom ever recorded off the West Coast.

The effects stretch from Central California to British Columbia, and possibly as far north as Alaska. Dangerous levels of the natural toxin domoic acid have shut down recreational and commercial shellfish harvests in Washington, Oregon and California this spring, including the lucrative Dungeness crab fishery off Washington’s southern coast and the state’s popular razor-clam season.

At the same time, two other types of toxins rarely seen in combination are turning up in shellfish in Puget Sound and along the Washington coast, said Vera Trainer, manager of the Marine Microbes and Toxins Programs at the Northwest Fisheries Science Center in Seattle.

“The fact that we’re seeing multiple toxins at the same time, we’re seeing high levels of domoic acid, and we’re seeing a coastwide bloom — those are indications that this is unprecedented,” Trainer said.

Scientists suspect this year’s unseasonably high temperatures are playing a role, along with “the blob” — a vast pool of unusually warm water that blossomed in the northeastern Pacific late last year. The blob has morphed since then, but offshore waters are still about two degrees warmer than normal, said University of Washington climate scientist Nick Bond, who coined the blob nickname.

“This is perfect plankton-growing weather,” said Dan Ayres, coastal shellfish manager for the Washington Department of Fish and Wildlife.

Domoic-acid outbreaks aren’t unusual in the fall, particularly in razor clams, Ayres said. But the toxin has never hit so hard in the spring, or required such widespread closures for crabs.

“This is new territory for us,” Ayres said. “We’ve never had to close essentially half our coast.”

Heat is not the only factor spurring the proliferation of the marine algae that produce the toxins, Trainer said. They also need a rich supply of nutrients, along with the right currents to carry them close to shore.

Scientists onboard the NOAA research vessel Bell M. Shimada will collect water and algae samples, measure water temperatures and also test fish like sardines and anchovies that feed on plankton. The algae studies are being integrated with the ship’s prime mission, which is to assess West Coast sardine and hake populations.

The ship will sample from the Mexican border to Vancouver Island in four separate legs.

“By collecting data over the full West Coast with one ship, we will have a much better idea of where the bloom is, what is causing it, and why this year,” University of California, Santa Cruz ocean scientist Raphael Kudela said in an email.

He and his colleagues found domoic-acid concentrations in California anchovies this year as high as any ever measured. “We haven’t seen a bloom that is this toxic in 15 years,” he wrote. “This is possibly the largest event spatially that we’ve ever recorded.”

On Washington’s Long Beach Peninsula, Ayres recently spotted a sea lion wracked by seizures typical of domoic-acid poisoning. The animal arched its neck repeatedly, then collapsed into a fetal position and quivered. “Clearly something neurological was going on,” he said.

Wildlife officials euthanized the creature and collected fecal samples that confirmed it had eaten prey — probably small fish — that in turn had fed on the toxic algae.

Ayres’ crews collect water and shellfish samples from around the state, many of which are analyzed at the Washington Department of Health laboratory in Seattle. DOH also tests commercially harvested shellfish, so consumers can be confident that anything they buy in a market is safe to eat, said Jerry Borchert, the state’s marine biotoxin coordinator.

But for recreational shellfish fans, the situation has been fraught this year even inside Puget Sound.

“It all really started early this year,” Borchert said.

Domoic-acid contamination is rare in Puget Sound, but several beds have been closed this year because of the presence of the toxin that causes paralytic shellfish poisoning (PSP) and a relatively new threat called diarrhetic shellfish poisoning (DSP). The first confirmed case of DSP poisoning in the United States occurred in 2011 in a family that ate mussels from Sequim Bay on the Olympic Peninsula, Borchert said.

But 2015 is the first time regulators have detected dangerous levels of PSP, DSP and domoic acid in the state at the same time — and in some cases, in the same places, he said. “This has been a really bad year overall for biotoxins.”

Over the past decade, Trainer and her colleagues have been working on models to help forecast biotoxin outbreaks in the same way meteorologists forecast long-term weather patterns, like El Niño. They’re also trying to figure out whether future climate change is likely to bring more frequent problems.

At a recent conference in Sweden on that very question, everyone agreed that “climate change, including warmer temperatures, changes in wind patterns, ocean acidification, and other factors will influence harmful algal blooms,” Kudela wrote. “But we also agreed we don’t really have the data yet to test those hypotheses.”

On past research voyages, Trainer and her team discovered offshore hot spots that seem to be the initiation points for outbreaks. There’s one in the so-called Juan de Fuca Eddy, where the California current collides with currents flowing from the Strait of Juan de Fuca. Another is Heceta Bank, a shallow, productive fishing ground off the Oregon coast, where nutrient-rich water wells up from the deep.

“These hot spots are sort of like crockpots, where the algal cells can grow and get nutrients and just stew,” Trainer said.

Scientists have also unraveled the way currents can sweep algae from the crockpots to the shore. “But what we still don’t know is why are these hot spots hotter in certain years than others,” Trainer said. “Our goal is to try to put this story together once we have data from the cruises.”

Read the original post: http://www.seattletimes.com

New study shows Arctic Ocean rapidly becoming more corrosive to marine species

Chukchi and Beaufort Seas could become less hospitable to shelled animals by 2030

New research by NOAA, University of Alaska, and Woods Hole Oceanographic Institution in the journal Oceanography shows that surface waters of the Chukchi and Beaufort seas could reach levels of acidity that threaten the ability of animals to build and maintain their shells by 2030, with the Bering Sea reaching this level of acidity by 2044.

“Our research shows that within 15 years, the chemistry of these waters may no longer be saturated with enough calcium carbonate for a number of animals from tiny sea snails to Alaska King crabs to construct and maintain their shells at certain times of the year,” said Jeremy Mathis, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory and lead author. “This change due to ocean acidification would not only affect shell-building animals but could ripple through the marine ecosystem.”

A team of scientists led by Mathis and Jessica Cross from the University of Alaska Fairbanks collected observations on water temperature, salinity and dissolved carbon during two month-long expeditions to the Bering, Chukchi and Beaufort Seas onboard United States Coast Guard cutter Healy in 2011 and 2012.

These data were used to validate a predictive model for the region that calculates the change over time in the amount of calcium and carbonate ions dissolved in seawater, an important indicator of ocean acidification. The model suggests these levels will drop below the current range in 2025 for the Beaufort Sea, 2027 for the Chukchi Sea and 2044 for the Bering Sea. “A key advance of this study was combining the power of field observations with numerical models to better predict the future,” said Scott Doney, a coauthor of the study and a senior scientist at the Woods Hole Oceanographic Institution.

A form of calcium carbonate in the ocean, called aragonite, is used by animals to construct and maintain shells.  When calcium and carbonate ion concentrations slip below tolerable levels, aragonite shells can begin to dissolve, particularly at early life stages.  As the water chemistry slips below the present-day range, which varies by season, shell-building organisms and the fish that depend on these species for food can be affected.

This region is home to some of our nation’s most valuable commercial and subsistence fisheries. NOAA’s latest Fisheries of the United States report estimates that nearly 60 percent of U.S. commercial fisheries landings by weight are harvested in Alaska. These 5.8 billion pounds brought in $1.9 billion in wholesale values or one third of all landings by value in the U.S. in 2013.

The continental shelves of the Bering, Chukchi and Beaufort Seas are especially vulnerable to the effects of ocean acidification because the absorption of human-caused carbon dioxide emissions is not the only process contributing to acidity.  Melting glaciers, upwelling of carbon-dioxide rich deep waters, freshwater input from rivers and the fact that cold water absorbs more carbon dioxide than warmer waters exacerbates ocean acidification in this region.

“The Pacific-Arctic region, because of its vulnerability to ocean acidification, gives us an early glimpse of how the global ocean will respond to increased human-caused carbon dioxide emissions, which are being absorbed by our ocean,” said Mathis. “Increasing our observations in this area will help us develop the environmental information needed by policy makers and industry to address the growing challenges of ocean acidification.”

University of Alaska researcher Jessica Cross tests water samples during Arctic research cruise on USCG cutter Healy. (Mathis/NOAA)

 

The crew lowers sensors that measure water temperature, salinity and dissolved carbon in the Arctic Ocean. (Mathis/NOAA)

Read the original post: http://research.noaa.gov