Posts Tagged research

Mar 9 2011

Shifting spring: Arctic plankton blooming up to 50 days earlier now

By Brian Vastag
Washington Post Staff Writer

A light micrograph of plankton including water fleas (family Daphniidae) (Getty Images/oxford Scientific)

Climate researchers have long warned that the Arctic is particularly vulnerable to global warming. The dramatic shrinking of sea ice in areas circling the North Pole highlights those concerns.

A new report finds that the disappearing ice has apparently triggered another dramatic event – one that could disrupt the entire ecosystem of fish, shellfish, birds, and marine mammals that thrive in the harsh northern climate.

Each summer, an explosion of tiny ocean-dwelling plants and algae, called phytoplankton, anchors the Arctic food web.

But these vital annual blooms of phytoplankton are now peaking up to 50 days earlier than they did just 14 years ago, satellite data show.

“The ice is retreating earlier in the Arctic, and the phytoplankton blooms are also starting earlier,” said study leader Mati Kahru, an oceanographer at the Scripps Institution of Oceanography in San Diego.

Read the rest of the story here.

Feb 15 2011

Sardine collapse due to multiple causes

This commentary was originally published in the Monterey County Herald.

By D.B. PLESCHNER
Guest commentary

On Jan. 30 The Herald published an excerpt, headlined “Overfishing triggered ruin of the sardine,” from a book by authors Steve Palumbi and Carolyn Sotka.

But there’s just one problem. The story is not entirely true.

“Ruin” is a harsh – and incorrect – headline to describe the storied sardine decline in the 1940s.   While the fish exodus may have ruined the canneries that once crowded Cannery Row, the sardines did return. And so has Monterey’s wetfish industry – so named because these species were canned ‘wet from the sea’ with little preprocessing.

In their column, Palumbi and Sotka actually allude to the fact that there is much more to the story than simple overfishing.  They note that, “Ed [Ricketts] also somehow knew that part of the problem was not overfishing, but a change in the ocean.”

In the 1960s, two decades after Ed Ricketts, scientists studying anaerobic sediments in the Santa Barbara Basin in Southern California discovered a natural historic record of pelagic fish populations, including sardine and anchovy.  These initial findings were the first step in proving Ed Ricketts’ earlier theories about ocean cycles.

In fact, analysis of the scale-deposition series showed that sardines and anchovies both tended to vary, layered in the deep mud, over a period of approximately 60 years, with the average time for sardine recovery about 30 years.

What’s more, the scale-deposition record counted nine major recoveries and subsequent collapses of the sardine population over a 1,700 year period.  Scientists Soutar, Isaacs, Baumgartner and others found the current recovery was not unlike those of the past in its rate or magnitude. Sardines were fated to decline with or without fishing pressure:  warm-water cycles favor sardines, and cold-water cycles favor anchovies.

Sardine recoveries and collapses

The sardine decline spurred the creation of the California Cooperative Fisheries Investigations (CalCOFI), a consortium composed of the National Marine Fisheries Service (NMFS), Scripps Institution of Oceanography and California Department of Fish and Game (DFG), whose focus was to study the sardine and other coastal pelagic species in the California Current System. California’s wetfish industry contributed funding and manpower to advance the research.

The DFG curtailed sardine harvest beginning in the late 1960s, and lifted the moratorium to allow a 1,000-ton harvest nearly 20 years later, after estimating a biomass of at least 20,000 tons.  The sardine resource expanded at an estimated 30 percent per year in the 1980s, stretching its boundaries from Southern California to the Pacific Northwest and Canada by the late 1990s.  New research and scientific models estimated the population at more than one million metric tons in 1999, when management authority transferred to the federal NMFS, which declared the population fully recovered.

Currently there’s a shift to a cold-water Pacific decadal oceanic cycle; the sardine population may again be entering another natural decline.  But now California’s sardine industry is limited to only 65 permitted vessels (63 active), restricted by a capacity goal and landing limits.   The sardine fishery is regulated under the federal Magnuson Act, with strict overfishing limits and annual catch limits to prevent overfishing.

The harvest control rule deducts 150,000 metric tons off the top of the biomass estimate (all fishing would be curtailed below that level) to provide forage for other marine life, as well as ensure a sustainable base population.  In addition, the allowed harvest rate is only 15 percent (net 10-11 percent after subtracting the 150,000 mt ‘cutoff’), far lower than other fishery exploitation rates.

Today the wetfish industry in Monterey is a traditional industry with a contemporary outlook.

Fishermen and markets actively engage in collaborative research on sardine and also market squid. The sons of the fathers and grandfathers before them who now harvest and process the wetfish complex– sardines, anchovies and market squid, all dynamic resources with natural cycles of abundance – still form the foundation of Monterey’s storied fishing community – culturally and economically.

These fishing families hope to carry on; and they should – wetfish resources are among the most sustainable marine life species in California, especially under today’s precautionary fishery management.

With 30 years of fishing industry experience, D.B. Pleschner is the executive director of the non-profit California Wetfish Producers Association, whose mission is to protect wetfish resources and the historic industry.  She’s a former contributing editor of Pacific Fishing magazine, and manager of the California Seafood Council.

Jan 22 2011

Rebuilding Global Fisheries [Video]

Ray Hilborn and Boris Worm comment on their findings in the Rebuilding Global Fisheries study:

Jan 20 2011

Ocean acidity: Small change, catastrophic results

Sometimes, seemingly small numbers can have remarkably big consequences. Miss a single free throw, and your team loses the championship. The economy slows by few percent, and millions of Americans are out of work. Your temperature rises by a degree or two, and you are down and out with a fever.

Nowhere, however, are the big consequences of little numbers becoming clearer than in the health of our oceans. There, a chemical shift of just 0.1 that’s right, just one-tenth of a point – is already causing “ocean acidification,” a massive, fundamental change that has enormous implications for marine life.

Read the rest of the article here.

Jan 18 2011

Dr. Ray Hilborn Discusses the State of World Fisheries, and more…[Video]

“Doomsday will come to fishes across the world’s oceans by 2048.”  That was the startling implication of findings published in 2006 by marine ecologist Boris Worm of Dalhousie University in Halifax, Canada, and several colleagues.

The projection, published in a paper in Science magazine, was about the relationship between biodiversity and ecosystem services in the oceans, and concluded that the world’s oceans were in bad shape, in part because of overfishing.

But many fisheries scientists were appalled.  In fact, one prominent critic was Dr. Ray Hilborn, a professor in the School of Aquatic and Fishery Sciences, University of Washington, specializing in natural resource management and conservation.

Trained in quantitative techniques for determining the abundance of fish stocks, Hilborn and others  questioned the methods used in Worm’s global assessment.  The conflict continued a charged and long-simmering debate between marine ecologists and fisheries scientists about the status of the world’s ocean ecosystems.

Yet, less than a year later, as recounted in a Science magazine article entitled “Détante in the Fisheries War,” Hilborn and Worm began meeting on neutral ground to hammer out their differences. Working under the auspices of the National Center for Ecological Analysis and Synthesis(NCEAS) in Santa Barbara, California, Hilborn and Worm brought together some 20 scientists from their respective disciplines as well as dozens of graduate students.

Initial results from this collaboration were published in the July 31, 2009 issue of Science magazine: Rebuilding Global Fisheries.

A new series of videos posted on WorldNews provides a video account of the highlights of this ground-breaking research.  Three videos feature Dr. Hilborn on the state of the world’s fisheries. Another video, including interviews with both Hilborn and Boris Worm, highlights findings in the Rebuilding Global Fisheries study, and yet another video presents Dr. Hilborn’s remarks at a Science Advisory Team meeting of the Marine Life Protection Act Initiative in southern California, critiquing the state’s rigid size and spacing guidelines governing marine protected area placement in the Golden State.

The first three videos are posted below:

Jan 17 2011

Concept of ‘fishing down food webs’ shown to be a myth

By Ray Hilborn (originally published in Pacific Fishing magazine, Jan. 2011)

Ray Hilborn

Perhaps no image of the impact of fish has captured the public as much as “fishing down food webs.”

The idea is very simple: Fishing begins, quite naturally, on the largest, most valuable fish. Once those are gone, fishermen move down the food webs to smaller, less valuable fish, and so on until the oceans are empty.

As Daniel Pauly, the prime apostle of the concept, has often said, we will soon have nothing to eat but jellyfish and zooplankton soup. This neatly fits the “apocalyptic” narrative that is so beloved by some environmental activists, but like many of these narratives, it is wishful thinking.

Pauly’s original paper, published in 1998, showed that the average fish caught in the world was becoming smaller and ever lower on the food web. This has been one of the most influential papers in the history of fisheries science. The “food web index” has been adopted by the Convention on Biodiversity and other groups as the best indicator of the health of marine ecosystems.

Read the rest here.

Jan 17 2011

Environmental Groups Concede Sea Otter Protections Deserve More Scientific Study

Peter Halmay diving

By Harry Liquornik and Peter Halmay

After a yearlong legal fight with two environmental groups, the federal government recently came to an agreement surrounding the future protection of the threatened California sea otter.

If you believe the rhetoric coming from the plaintiff groups, they scored a major victory.

According to their statements, the Otter Project and the Environmental Defense Center are now on the path to freeing the sea otters from government interference and allowing the animals to return to the waters off Southern California.

But that’s not really the whole story, or even the whole truth.

Instead of dealing with meaningful, yet difficult, water quality problems this ill-conceived lawsuit sought simplicity — allow sea otters to go find places to survive on their own.

Sadly, without even so much as demanding an update to the 2005 scientific research surrounding the sea otters’ habitat, and seemingly not allowing the government to comply with the Endangered Species Act, the lawsuit took aim at terminating a key element of the government’s sea otter recovery program.

What’s more, these groups also wanted to ignore the act’s requirements that demand a program for a listed threatened species — such as sea otters — must also avoid harming other listed species. In this case, two endangered native abalone species are a primary prey of the threatened sea otters and the abalone share the habitat that will likely be occupied by the sea otters if the management program is ultimately ended.

The program, which began in 1987, established a separate colony of sea otters at San Nicolas Island as an insurance policy to protect the species in the event of a major oil spill. The plan also set up a sea otter management zone to protect Southern California’s shellfish fisheries, which represent a critical part of the state’s marine ecosystem and are an important element of many coastal communities.

Despite what the lawsuit claimed, the program has been a success.

Currently, the San Nicolas Island colony boasts the healthiest sea otters in California; these animals are reproducing at double the rate of the mainland population. Conversely, the island success stands in stark contrast to the mainland population, where approximately 300 sea otters die each year.

It’s for these reasons that several groups who know that a comprehensive ecosystem-wide protection plan is much more effective than a species-by-species approach, intervened in the lawsuit. This coalition, headed by the California Sea Urchin Commission, understands that without a functional ecosystem management plan, all species are at risk, not just a single target species. And that’s why we must redouble our efforts to fulfill all the elements of the 1987 program.

Thankfully, the court-approved agreement forced the plaintiffs to ultimately agree with the Sea Urchin Commission and its partners on practically all points put forward — that updating the 2005 study was appropriate; all elements of a final decision should in fact depend on a new analysis; the U.S. Fish and Wildlife Service should consider impacts to other protected marine species; and it should also consider the negative impact that poor water quality is having on sea otters. So what did the plaintiffs get for their lawsuit efforts?

They got taxpayers to reimburse them $55,000 in legal fees for an agreement which they could have received with a written request and first-class stamp.

And what did the people of California get, besides an unnecessary bill? A chance for a comprehensive review of the translocation experiment and a chance to further develop a meaningful ecosystem-based management of the resources.

Harry Liquornik serves as chairman of the California Sea Urchin Commission and Peter Halmay is a former member of the Fish and Wildlife Service’s sea otter recovery implementation team. Both are commercial sea urchin divers.

Dec 18 2010

Commercial Market Squid Fishery Closes December 17

Based on landings information and projections, Department of Fish and Game (DFG) biologists expected that the season’s harvest limit of 118,000 short tons of market squid would be reached by Friday, December 17. The squid fishing season runs from April through the following March of each year, and the fishery closure will remain in effect through March 31, 2011. This is the first season the harvest limit has been attained since it was implemented by the Fish and Game Commission in 2004 as part of the California Market Squid Fishery Management Plan.

Squid fishermen and processors have assisted DFG in tracking daily catches this fall, as record squid abundance signaled the likelihood of reaching the harvest limit, established to ensure the squid fishery does not expand beyond levels experienced in the 1990s. “The wetfish industry and California Wetfish Producers Association (CWPA) are very pleased to partner with DFG to ensure a sustainable market squid resource and fishery,” says California Wetfish Producers Association Executive Director Diane Pleschner-Steele.

”The mission of the nonprofit CWPA is to facilitate collaborative research and management of our marine resources,” Pleschner-Steele explains.  “Our market squid research program predicted a good season this fall, but this has been truly amazing.”

Under the supervision of Dr. Doyle Hanan, retired DFG senior marine biologist supervisor formerly responsible for market squid and coastal pelagic fisheries, squid fishermen have learned how to tow scientific bongo nets to collect squid hatchlings, called paralarvae.  They time these field surveys to coincide with quarterly California Cooperative Fisheries Investigations (CalCOFI) oceanic research cruises.  Dr. Hanan has observed a correlation between increased paralarvae abundance and a productive fishery six- to nine months later.

(Learn more about CWPA’s market squid research program here.)

The presence of market squid is strongly correlated with environmental factors, such as water temperature and nutrient availability. In warm water years, such as during El Niño events, squid abundance drops sharply and landings decline. However, when water temperatures cool, even after severe warm water events, market squid numbers can rebound dramatically.

“Recent favorable environmental conditions generated the current surge in market squid abundance, says Dr. Hanan.  “The fact is there were plenty of adult squid and eggs produced to take advantage of these environmental conditions. This huge biomass has occurred while a squid fishery continued and a fishery management plan controlled fishing activities. From a fishery science and biological standpoint, this indicates that the management plan is indeed working.”

“We have had a banner year for market squid this year,” says Dale Sweetnam, DFG senior marine biologist who now oversees the commercial market squid fishery.  “In California, we have had squid landings from La Jolla to Half Moon Bay and reports that market squid are abundant off many of the offshore banks, the Channel Islands, as well as off Baja California.  The colder than normal water conditions we have observed since February have provided optimal conditions for squid spawning.”

According to the DFG News Release, market squid is by far California’s largest and most valuable commercial fishery. In 2009, just over 100,000 tons were landed with an ex-vessel value of $56.5 million. California market squid is used domestically for food – often identified as “calamari” in restaurants – and is an important international commodity. Last year, California fish businesses exported market squid to 36 countries with China the leading importer of California market squid.

The harvest limit is one of many provisions governing the squid fishery, which has been managed under the state’s Market Squid Fishery Management Plan (MSFMP) since 2005. The goals of the MSFMP are to ensure long-term conservation and sustainability of the market squid resource, reduce the potential for overfishing and provide a framework for management. In addition to the harvest limit, weekend closures were implemented to allow for periods of uninterrupted spawning each week.

The MSFMP was developed under the provisions set forth by California’s Marine Life Management Act (MLMA), which became law in 1999. The MLMA created state policies, goals and objectives to govern the conservation, sustainable use and restoration of California’s living marine resources.

(Read the entire DFG news release announcing the fishery closure here.)

Oct 12 2010

Dr. Doyle Hanan Talking Sardine Research on KNX-AM Los Angeles

Dr. Doyle Hanan was interviewed today on KNX-AM 1070 (Los Angeles) about the sardine research project. You can listen here.

Oct 1 2010

Pilot Jeff Laboff Talking Sardine Research on KTVA Ventura

Pilot Jeff Laboff was recently interviewed on KTVA-AM 1520 (Ventura) about the sardine research project.  You can listen here.