Feb 17 2017

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

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

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

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/

Feb 17 2017

Scientists: Major Oxygen Loss to Oceans Linked to Warming Climate

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SEAFOODNEWS.COM [Washington Post] by By Chris Mooney – February 16, 2017

A large research synthesis, published in one of the world’s most influential scientific journals, has detected a decline in the amount of dissolved oxygen in oceans around the world — a long-predicted result of climate change that could have severe consequences for marine organisms if it continues.

The paper, published Wednesday in the journal Nature by oceanographer Sunke Schmidtko and two colleagues from the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, found a decline of more than 2 percent in ocean oxygen content worldwide between 1960 and 2010. The loss, however, showed up in some ocean basins more than others. The largest overall volume of oxygen was lost in the largest ocean — the Pacific — but as a percentage, the decline was sharpest in the Arctic Ocean, a region facing Earth’s most stark climate change.

The loss of ocean oxygen “has been assumed from models, and there have been lots of regional analysis that have shown local decline, but it has never been shown on the global scale, and never for the deep ocean,” said Schmidtko, who conducted the research with Lothar Stramma and Martin Visbeck, also of GEOMAR.

Ocean oxygen is vital to marine organisms, but also very delicate — unlike in the atmosphere, where gases mix together thoroughly, in the ocean that is far harder to accomplish, Schmidtko explained. Moreover, he added, just 1 percent of all the Earth’s available oxygen mixes into the ocean; the vast majority remains in the air.

Climate change models predict the oceans will lose oxygen because of several factors. Most obvious is simply that warmer water holds less dissolved gases, including oxygen. “It’s the same reason we keep our sparkling drinks pretty cold,” Schmidtko said.

But another factor is the growing stratification of ocean waters. Oxygen enters the ocean at its surface, from the atmosphere and from the photosynthetic activity of marine microorganisms. But as that upper layer warms up, the oxygen-rich waters are less likely to mix down into cooler layers of the ocean because the warm waters are less dense and do not sink as readily.

“When the upper ocean warms, less water gets down deep, and so therefore, the oxygen supply to the deep ocean is shut down or significantly reduced,” Schmidtko said.

The new study represents a synthesis of literally “millions” of separate ocean measurements over time, according to GEOMAR. The authors then used interpolation techniques for areas of the ocean where they lacked measurements.

The resulting study attributes less than 15 percent of the total oxygen loss to sheer warmer temperatures, which create less solubility. The rest was attributed to other factors, such as a lack of mixing.

Matthew Long, an oceanographer from the National Center for Atmospheric Research who has published on ocean oxygen loss, said he considers the new results “robust” and a “major advance in synthesizing observations to examine oxygen trends on a global scale.”

Long was not involved in the current work, but his research had previously demonstrated that ocean oxygen loss was expected to occur and that it should soon be possible to demonstrate that in the real world through measurements, despite the complexities involved in studying the global ocean and deducing trends about it.

That’s just what the new study has done.

“Natural variations have obscured our ability to definitively detect this signal in observations,” Long said in an email. “In this study, however, Schmidtko et al. synthesize all available observations to show a global-scale decline in oxygen that conforms to the patterns we expect from human-driven climate warming. They do not make a definitive attribution statement, but the data are consistent with and strongly suggestive of human-driven warming as a root cause of the oxygen decline.

“It is alarming to see this signal begin to emerge clearly in the observational data,” he added.

“Schmidtko and colleagues’ findings should ring yet more alarm bells about the consequences of global warming,” added Denis Gilbert, a researcher with the Maurice Lamontagne Institute at Fisheries and Oceans Canada in Quebec, in an accompanying commentary on the study also published in Nature.

Because oxygen in the global ocean is not evenly distributed, the 2 percent overall decline means there is a much larger decline in some areas of the ocean than others.

Moreover, the ocean already contains so-called oxygen minimum zones, generally found in the middle depths. The great fear is that their expansion upward, into habitats where fish and other organism thrive, will reduce the available habitat for marine organisms.

In shallower waters, meanwhile, the development of ocean “hypoxic” areas, or so-called “dead zones,” may also be influenced in part by declining oxygen content overall.

On top of all of that, declining ocean oxygen can also worsen global warming in a feedback loop. In or near low oxygen areas of the oceans, microorganisms tend to produce nitrous oxide, a greenhouse gas, Gilbert writes. Thus the new study “implies that production rates and efflux to the atmosphere of nitrous oxide … will probably have increased.”

The new study underscores once again that some of the most profound consequences of climate change are occurring in the oceans, rather than on land. In recent years, incursions of warm ocean water have caused large die-offs of coral reefs, and in some cases, kelp forests as well. Meanwhile, warmer oceans have also begun to destabilize glaciers in Greenland and Antarctica, and as they melt, these glaciers freshen the ocean waters and potentially change the nature of their circulation.

When it comes to ocean deoxygenation, as climate change continues, this trend should also increase — studies suggest a loss of up to 7 percent of the ocean’s oxygen by 2100. At the end of the current paper, the researchers are blunt about the consequences of a continuing loss of oceanic oxygen.

“Far-reaching implications for marine ecosystems and fisheries can be expected,” they write.


Copyright © 2016 Seafoodnews.com

 

Jan 12 2017

Ocean acidification to hit West Coast Dungeness crab fishery, new assessment shows

The acidification of the ocean expected as seawater absorbs increasing amounts of carbon dioxide from the atmosphere will reverberate through the West Coast’s marine food web, but not necessarily in the ways you might expect, new research shows.

Dungeness crabs, for example, will likely suffer as their food sources decline. Dungeness crab fisheries valued at about $220 million annually may face a strong downturn over the next 50 years, according to the research published Jan. 12 in the journal Global Change Biology. But pteropods and copepods, tiny marine organisms with shells that are vulnerable to acidification, will likely experience only a slight overall decline because they are prolific enough to offset much of the impact, the study found.

Dungeness crab.jkirkhart35/Flickr

Marine mammals and seabirds are less likely to be affected by ocean acidification, the study found.

“What stands out is that some groups you’d expect to do poorly don’t necessarily do so badly – that’s probably the most important takeaway here,” saidKristin Marshall, lead author of the study who pursued the research as a postdoctoral researcher at the University of Washington and NOAA Fisheries’ Northwest Fisheries Science Center. “This is a testament in part to the system’s resilience to these projected impacts. That’s sort of the silver lining of what we found.”

While previous studies have examined the vulnerability of particular species to acidification in laboratories, this is among the first to model the effects across an entire ecosystem and estimate the impacts on commercial fisheries.

“The real challenge is to go from experiments on what happens to individual animals in the lab over a matter of weeks, to try to capture the effects on the whole population and understand how vulnerable it really is,” said Isaac Kaplan, a research scientist at NOAA Fisheries’ Northwest Fisheries Science Center in Seattle.

The research used sophisticated models of the California Current ecosystem off the Pacific Coast to assess the impacts of a projected 0.2 unit decline in the pH of seawater in the next 50 years, which equates to a 55 percent increase in acidity. The California Current is considered especially vulnerable to acidification because the upwelling of deep, nutrient-rich water low in pH already influences the West Coast through certain parts of the year.

The ocean absorbs about one-third of carbon dioxide released into the atmosphere from the burning of fossil fuels, which has led to a 0.1 unit drop in pH since the mid-1700s.

The research built on an earlier effort by NOAA scientists Shallin Busch and Paul McElhanythat quantified the sensitivity of various species to acidification, as originally reported in 393 separate papers. In a novel approach, Busch and McElhany weighed the evidence for each species based on its reported sensitivity in the laboratory, relevance to the California Current and agreement between studies.

This synthesis by Busch and McElhany identified 10 groups of species with highest vulnerability to acidification. Marshall and colleagues incorporated this into the ecosystem model to examine how acidification will play out in nature. The study particularly examined the effects on commercially important species including Dungeness crab; groundfish such as rockfish, sole and hake; and coastal pelagic fish such as sardines and anchovy over the period from 2013 to 2063.

graphic showing changes based on new study
The study modeled the potential risks of ocean acidification (under a future decrease in pH) on the West Coast marine food web and fisheries over 50 years, from 2013 to 2063. NOAA Fisheries

“This was basically a vulnerability assessment to sharpen our view of where the effects are likely to be the greatest and what we should be most concerned about in terms of how the system will respond,” said Tim Essington, a UW professor of aquatic and fishery sciences and a co-author of the research.

The study provides a foundation for further research into the most affected species, he said.

Although earlier studies have shown that Dungeness crab larvae is vulnerable to acidification, the assessment found that the species declined largely in response to declines in its prey – including bivalves such as clams and other bottom-dwelling invertebrate species.

Since Dungeness crab is one of the most valuable fisheries on the West Coast, its decline would have some of the most severe economic effects, according to the research. Groundfish such as petrale sole, Dover sole and deep-dwelling rockfish are also expected to decline due to acidification, according to the assessment. However, fisheries for those species are much less valuable so the economic impact would not be as large.

Coastal pelagic fish were only slightly affected.

“Dungeness crab is a bigger economic story than groundfish,” Kaplan said. “There are winners and losers, but the magnitude of the impact depends on how important the species is economically.”

The research was funded by the NOAA Ocean Acidification Program and the National Centers for Coastal Ocean Science. Marshall was supported by a National Research Council fellowship.

###

For more information, contact Marshall at kmarsh2@uw.edu and Kaplan atisaac.kaplan@noaa.gov 206-302-2446.

This piece was adapted from a Northwest Fisheries Science Center news release.

 

Jan 12 2017

Squid boats dot Malibu coast: Roughly 40,157 tons of squid caught this season

Squid boats are seen from Malibu’s Zuma Beach on a recent January evening. Suzanne Guldimann/22nd Century Media


Almost every night this winter, bright lights have appeared off the coast of Malibu.

It’s an eerie sight on a foggy evening, suggesting something unearthly or supernatural, but the only thing these ghostly lights portend is the presence of Doryteuthis opalescens, the common market squid.

It’s a good omen for California’s seafood industry. Market squid is one of California’s largest commercial fisheries, and tons of frozen California calamari are shipped all over the world each year. However, the species had almost entirely disappeared from Southern California waters last year. The absence of squid is being blamed on El Niño.

California Department of Fish and Wildlife environmental scientist Laura Ryley studies squid.

“Market squid was very limited in Southern California last year,” she told The Malibu Surfside News. 

Ryley explained that the squid are thought to react to the warmer water generated by El Niño, migrating further north in search of the right water temperature and conditions for spawning.

“The commercial fishery was landing squid in Eureka and off the coast of Oregon last year,” Ryley said.

She added that the management plan for the species implemented in 2005 provides an opportunity for scientists to gather data on the size, sex and abundance of the species. That data show that market squid generally have the ability to recover swiftly after an El Niño event.

“The patterns in the past show the squid are still able to reproduce and that they bounce back quickly,” she said.

While concerns are being raised over the potential impact of prolonged ocean warming on the species, the return of more normal temperature conditions in the Pacific this winter appears to have signaled the return of the squid. 

An abundance of cephalopods isn’t just an auspicious sign for the fishing industry. It may mean fewer problems for local sea lion and elephant seal populations, which have experienced mass stranding events blamed in part on the same warm water that impacted the squid and other key prey species like Pacific sardines and mackerel.

“I’ve heard that market squid isn’t the sea lion’s favorite, but they will eat it,” Ryley said. “It’s an important food for other species as well. Salmonids eat them. So do sea birds.”

The California Department of Fish and Wildlife’s management plan for the market squid fishery limits the seasonal catch to 118,000 tons per season. The season opens April 1 each year, and runs until the limit is met or until March 31, whichever comes first.

This season got off to a slow start but is accelerating. As of Dec. 30, 2016, the total landings of market squid were 40,157.6 tons.

That’s in sharp contrast to 2013, the last big year for squid, when the quota for the season was reached by early November, according to NOAA Fisheries data, but a major increase from 2014 and 2015, when the numbers plummeted in Southern California.

In the Malibu area, autumn and winter are the peak time for commercial squid fishing. The shallow waters along the Malibu coast are usually a prime location for squid, which migrate to the shallow, sandy, near-shore area in the fall to spawn.

Special light boats equipped with high wattage bulbs attract the squid, which are caught using either seine or scoop nets. The lights are supposed to be shielded to reduce the impact on migratory birds and coastal residents, but compliance isn’t 100 percent yet.

The Monterey Bay Aquarium’s Seafood Watch program rates market squid as a “good alternative” for sustainability, but most of the California catch is frozen and shipped to Asia. 

“The American market prefers squid with a thicker mantle,” Ryley said. 

Market squid rarely grow to be more than 10 inches in length. They are short-lived; 9-10 months is usually the maximum life span, and they spawn just once, at the end of their lives.

Squid can only be caught on weekdays from the U.S.-Mexico border to the California-Oregon border. From noon Friday to noon Sunday the squid are given a “break.”

“The thinking behind that is to give them a time for uninterrupted spawning,” Ryley explained.

Squid fishing is permitted all along the Malibu coast, even within the boundaries of the Point Dume State Marine Conservation Area, located off the coast of Zuma and Lechuza beaches. Only Point Dume State Marine Reserve (Paradise Cove to Westward Beach) is off limits.

With more than half the season’s limit still swimming around in the Pacific, it’s a safe bet that the unearthly green and pink glow of the squid boats will continue to light up Malibu’s coast, drawing the curiosity of more than just squid.


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

Jan 5 2017

Scientists: Global Ocean Circulation Could Be More Vulnerable to Shutdown Than We Thought

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SEAFOODNEWS.COM [The Washington Post] by Chelsea Harvey – January 5, 2017

Intense future climate change could have a far different impact on the world than current models predict, suggests a thought-provoking new study just out in the journal Science Advances. If atmospheric carbon dioxide concentrations were to double in the future, it finds, a major ocean current — one that helps regulate climate and weather patterns all over the world — could collapse. And that could paint a very different picture of the future than what we’ve assumed so far.

The Atlantic meridional overturning circulation, or AMOC, is often described as a large oceanic conveyor belt. It’s a system of water currents that transports warm water northward from the Atlantic toward the Arctic, contributing to the mild climate conditions found in places like Western Europe. In the Northern Atlantic, the northward flowing surface water eventually cools and sinks down toward the bottom of the ocean, and another current brings that cooler water back down south again. The whole process is part of a much larger system of overturning currents that circulates all over the world, from pole to pole.

But some scientists have begun to worry that the AMOC isn’t accurately represented in current climate models. They say that many models portray the current as being more stable than real-life observations suggest it actually is. Recent studies have suggested that the AMOC is weakening, although there’s some scientific debate about how much of this has been caused by human activities and how much by natural variations.

Nevertheless, the authors of the new study point out, many climate models assume a fairly stable AMOC — and that could be affecting the predictions they make for how the ocean will change under future climate change. And because overturning circulation patterns have such a significant effect on climate and weather all over the world, this could have big implications for all kinds of other climate-related projections as well.

“This is a very common and well-known issue in climate models,” said the new study’s lead author, Wei Liu, a postdoctoral associate at Yale University, who conducted the work while at the University of California at San Diego. “I wanted to see, if I use a corrected model, how this will affect the future climate change.”

Liu and colleagues from the UC-San Diego and the University of Wisconsin at Madison took a commonly used climate model and corrected for what they considered to be the AMOC stability bias. Then they ran an experiment to see how the correction would affect the model’s projections under future climate change. They instantaneously doubled the atmospheric carbon dioxide concentration from present-day levels in both the corrected and uncorrected models, and then they let both models run for hundreds of simulated years.

The differences were striking. In the uncorrected climate model, the AMOC weakens for a while, but eventually recovers. In the corrected model, however, the AMOC continues to weaken and after 300 years, it collapses altogether.

In a commentary also published today in RealClimate, Stefan Rahmstorf, an oceans physics expert at the Potsdam Institute for Climate Impact Research, explained how such a collapse could occur when the AMOC gets too weak.

“Freshwater continually flows into the northern Atlantic through precipitation, rivers and ice-melting,” he wrote. “But supply of salty waters from the south, through the Gulf Stream System, balances this. If however the current slows, there is less salt supply, and the surface ocean gets less salty.”

Because freshwater is less dense than salty water, this process can lead to a kind of stratification, in which the lighter freshwater gets stuck on the surface of the ocean and can’t sink to the bottom when it reaches the cooler north. When this happens, the overturning process that drives the current back down south again can’t occur.

“There is a critical point when this becomes an unstoppable vicious circle,” Rahmstorf wrote. “This is one of the classic tipping points in the climate system.”

The resulting climate consequences, compared to the uncorrected model, are also dramatic. Without the usual transport of warm water into the north, the corrected model predicts a marked cooling over the northern Atlantic, including in the United Kingdom, Iceland and northwestern Europe, as well as in the Arctic, where sea ice begins to expand.

Because the AMOC is part of a larger global conveyor system, which ferries warm and cold currents between the equator and both poles, the model predicts disruptions in other parts of the world as well. Without cold water moving back down south again, the corrected model indicates a stronger warming pattern south of the equator than what’s predicted by the uncorrected model, causing a polarization in precipitation patterns over the Americas — more rain for places like northeastern Brazil and less rain for Central America. The model also predicts a greater reduction in sea ice for the Antarctic.

All this doesn’t necessarily mean that everything we thought we knew about the future climate is wrong. For one thing, most modern climate projections focus on the next few decades or so, noted Thomas Haine, an expert on ocean circulation at Johns Hopkins University. And within 50 years or so, both the uncorrected and corrected models in the new study produce similar results. It is only after that, under extreme warming, that the current shifts.

Liu also cautioned that certain aspects of the experiment can’t exactly be considered realistic — for instance, instantaneously doubling the atmospheric carbon dioxide concentration. Current climate efforts are aimed at keeping us from ever getting to such a point — but even if we did, the process would happen gradually, not overnight. So the model’s outcome might have been different if the researchers had adopted a more realistic scenario.

Haine also suggested that the correction in the new study may have actually been a bit too strong, compared to actual observations — in other words, the modeled AMOC is “probably more unstable than the real system,” he said.

Rahmstorf also pointed out this issue in his commentary — but he added that the climate model used also did not account for an influx of meltwater from Greenland under future climate change, an event that recent research suggests could substantially speed the AMOC’s weakening.

“With unmitigated emissions . . . the Gulf Stream System weakens on average by 37 percent by the year 2300 without Greenland melt,” he notes. “With Greenland meltwater this doubles to 74 percent. And a few months ago, a study with a high-resolution ocean model appeared, suggesting that the meltwater from Greenland is likely to weaken the AMOC considerably within a few decades.”

The fact that current models don’t take this melting into account is further support for the idea that scientists have been underestimating the risk of a future AMOC collapse, he suggested.

According to Liu, the new study serves to make a point about the dramatic effects that can occur when corrections are made in climate models, as well as the AMOC’s major role in the global climate. By tweaking a climate model to make it more consistent with real-life observations, very different outcomes may be observed, Liu noted.

“I would say that it is reasonably well-accepted that a current generation of climate models [is] missing the essential physics in representing the AMOC,” said Haine. And he added that the new study “points to the need to fix these biases in the climate models.”


Peggy Parker, Science and Sustainability Editor
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Dec 16 2016

Monterey harbormaster to retire after 21 years

Monterey >> Harbormaster Steve Scheiblauer’s days walking the docks down at the waterfront are numbered.

That’s because after 21 years, Scheiblauer is retiring. His last day will be Feb. 21.

“I’ve been doing this for 41 years – I’ll be 68 by the time I retire,” said Scheiblauer. “I’m ready to do some other things – travel a bit, do a little bit of writing.”

Scheiblauer has been serving in the role since January 1995 when then-City Manager Fred Meurer brought him on board.

That was after Scheiblauer worked as Santa Cruz’s harbormaster for some 20 years, from 1975 to 1995.

Since that time, he’s seen the city’s marina replaced and took a central role in nurturing Monterey’s commercial fisheries.

“We had to get money, permits and the design together to replace it,” said Scheiblauer, about the rebuilding of the old marina back in 1995 soon after he became harbormaster. “It was one of the largest capital projects that the city has ever done.”

Meurer remembers it well.

“There was continual arguing over the slips in the marina and a waiting list 100 years long,” said Meurer. “Steve brought order to it all in a very calm way and did a great job managing the total refurbishment of the marina with little impact on the users.”

Scheiblauer said it’s the development of good relationships that’s key to getting things done with the boating community.

“A lot of changes were needed at the city’s waterfront and I’ve had the support for that and couldn’t have done it without the city council and city management both past and present,” he said.

But in doing so, Monterey Community Services Director Kim Bui-Burton said he’s represented the city and its marine and ocean life interests to a very high standard.

“He’s succeeded in managing a lot of the harbor operations and really responding to the boating community,” said Bui-Burton.

While Scheiblauer said he’s especially proud of that constructive relationship that Monterey has with its commercial fishermen and sailors, Bui-Burton also noted his role in developing the city’s Fishing Community Sustainability Plan.

“It’s really the blueprint for retaining our community’s fishing heritage and making it viable into the 21st century,” said Bui-Burton.

While Scheiblauer works to finish the current project of replacing the wooden parking deck down at Wharf 1, he said once he’s retired he’ll be forming his own consultant business. Marine Alliances Consulting will specialize in harbor management, fisheries, economics and ocean environmental issues.

“I wanted to make use of some of the things I’ve learned over the years,” he said.

Meurer said it’s Scheiblauer’s knowledge and people skills that will leave a huge void in the city’s organization once he’s done.

“He’s a huge advocate for the protection of the marine environment while protecting the fishing heritage of the port of Monterey.” said Meurer. “He knew the rules of the sanctuary and the coastal act and he used his knowledge of rules and regulations to do his best for the city of Monterey and the Monterey harbor. He’s the epitome of what a public servant should be.”

Dec 15 2016

NOAA: ‘Arctic Is Warming at Least Twice as Fast as the Rest of the Planet’

The Arctic broke multiple climate records and saw its highest temperatures ever recorded this year, according to the National Oceanic and Atmospheric Administration’s (NOAA) annual Arctic Report Card released Tuesday.

Map: Temperatures across the Arctic from October 2015-September 2016 compared to the 1981-2010 average. Graph: Yearly temperatures since 1900 compared to the 1981-2010 average for the Arctic (orange line) and the globe (gray).NOAA

The report shows surface air temperature in September at the highest level since 1900 “by far” and the region set new monthly record highs in January, February, October and November. “The Arctic as a whole is warming at least twice as fast as the rest of the planet,” report author and NOAA climate scientist Jeremy Mathis told NPR.

Watch the video from NOAA on the annual Arctic Report Card below:

Report Card Highlights

  • The average surface air temperature for the year ending September 2016 is by far the highest since 1900 and new monthly record highs were recorded for January, February, October and November 2016.
  • After only modest changes from 2013-2015, minimum sea ice extent at the end of summer 2016 tied with 2007 for the second lowest in the satellite record, which started in 1979.
  • Spring snow cover extent in the North American Arctic was the lowest in the satellite record, which started in 1967.
  • In 37 years of Greenland ice sheet observations, only one year had earlier onset of spring melting than 2016.
  • The Arctic Ocean is especially prone to ocean acidification, due to water temperatures that are colder than those further south. The short Arctic food chain leaves Arctic marine ecosystems vulnerable to ocean acidification events.
  • Thawing permafrost releases carbon into the atmosphere, whereas greening tundra absorbs atmospheric carbon. Overall, tundra is presently releasing net carbon into the atmosphere.
  • Small Arctic mammals, such as shrews, and their parasites, serve as indicators for present and historical environmental variability. Newly acquired parasites indicate northward sifts of sub-Arctic species and increases in Arctic biodiversity.

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

Dec 5 2016

D.B. Pleschner: Extremists manufacture anchovy ‘crisis’ where none exists

By D.B. Pleschner

Guest commentary

When the National Marine Fisheries Service (NMFS) recently reapproved the 2017 annual catch limit for the central stock of anchovy at 25,000 metric tons (mt), environmental extremists immediately cried foul.

Press releases with doomsday headlines claimed that the anchovy catch limit is now higher than the total population of fish in the sea. Environmentalists claim the anchovy resource has “collapsed” and the current catch limit is dangerously high.

But is the anchovy population really decimated, or are these alarmists simply manufacturing another anti-fishing crisis?

Their claims are based on a paper by Alec MacCall, pegging the central anchovy stock at about 18,000 mt. However, the paper analyzed egg and larval data collected over time in California Cooperative Fishery Investigations (CalCOFI) surveys, conducted in the Southern California Bight — and the conclusion is fundamentally flawed. Other scientists now acknowledge that the CalCOFI cruises do not cover the full range of anchovy, missing both Mexico and areas north of the CalCOFI survey track, as well as the nearshore, where a super-abundance of anchovy now reside, say fishermen.

The CalCOFI survey was designed to track sardine, not anchovy. It misses the nearshore biomass where age 0-1 anchovy live and huge schools of anchovy have been observed since 2013. But the MacCall analysis deliberately omitted nearshore egg-larval data. In addition, peak spawning for anchovy is February-March, but CalCOFI surveys run in January and April, as did the MacCall analysis, thus both captured only the tails of spawning.

Clearly, current data are inadequate to develop an accurate anchovy population estimate. At the November 2016 Pacific Fishery Management Council meeting, scientists, the management team and most council members agreed.

In reality, anchovies are now amazingly abundant from San Diego to Northern California. Scientific data as well as fishermen’s observation bear this out:

• Recent NOAA field surveys documented increased anchovy recruitment and multiple year classes, although data from the 2016 summer survey are still undergoing analysis.

• A 2015 NOAA juvenile rockfish cruise report found evidence of record numbers of anchovy larvae and pelagic juveniles, and saw an abundance of anchovy again in 2016.

And consider reports from fishermen like Neil Guglielmo, who fished anchovy from Half Moon Bay to Monterey in the summer of 2016. He saw thousands of tons of anchovy — school after school running from San Francisco to the Farallon Islands, and down the coast to Monterey and beyond. Similar comments come from many fishermen who fish nearshore waters the length of the California coast.

The big increase in anchovy abundance in nearshore waters in recent years has precipitated a record whale-watching spectacle, recounted in media reports from San Francisco to San Diego. And while doomsday press releases and news stories regurgitate environmentalist claims that the anchovy resource has “collapsed,” Monterey Bay Whale Watch posted a video on Facebook of dozens of sea lions and a humpback whale feasting on thousands of anchovies — only two miles from Monterey Harbor!

The bottom line is that anchovy management employs an extremely precautionary approach, capping the allowed harvest at 25 percent of the average overfishing limit estimated to be harvested sustainably over the long term.

So why are ENGOs lobbying to cut the harvest limit to 7,000 mt, drastically lower than the federal limit, even though the draconian reduction would inflict serious harm to California’s historic fishing industry, especially in Monterey?

Scientists acknowledge that anchovy abundance is highly variable, and that variability occurs even without a fishery. Given multiple lines of evidence of anchovy recruitment, clearly there is no biological crisis, but there could be a serious socioeconomic problem if the small anchovy harvest limit is further restricted.

As the Pacific Fishery Management Council deliberates anchovy management, we hope a credible and thorough scientific assessment process and best available common sense will prevail. Evidence of recent anchovy recruitment must be factored into future management decisions; politics should not drive the outcome.

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


Originally published: http://www.montereyherald.com/opinion/

Dec 5 2016

Local harbor seal population appears down, but should rebound

Harbor seals haul out of the water at the beach at Hopkins Marine Station in Pacific Grove on Wednesday. (David Royal - Monterey Herald)

Harbor seals haul out of the water at the beach at Hopkins Marine Station in Pacific Grove on Wednesday. (David Royal – Monterey Herald)

Pacific Grove >> The stretch of coastline from Fisherman’s Wharf in Monterey along the rocky shores of Pacific Grove to Pebble Beach is home to a shrinking population of Pacific harbor seals, local experts said.

According to a population census taken on Nov. 25 by husband and wife Thom and Kim Akeman, volunteers with the National Oceanic and Atmospheric Association’s shoreline program Bay Net, the Pacific Grove Harbor seal population has declined by one-third. Numbers have plunged from about 700 individuals, based on preliminary counts taken by Monterey Bay Aquarium researcher Teri Nicholson in the 1990s, to fewer than 500 in the last couple of years, the Akemans reported. Uncharacteristically warm waters, which depleted the marine environment of oxygen and food, are to blame, they added.

But the bad news may not be as critical as it seems, said Dr. Andrew DeVogelaere, research director at the Monterey Bay National Marine Sanctuary.

“A lot of ocean species have evolved to have a few bad years,” he said. “The population will dip down, and then with more food, go up again.”

The normally cool water off the Central Coast is an oxygen-filled, nutrient-rich haven for all local marine life, from tiny anchovies to magnanimous humpback whales. But 2014’s mild winter made for uncharacteristically warm waters. Because of El Niño, the sea is still above its normal temperature today. The National Marine Fisheries Service, whose scientists have 35 years of oceanic climate data from California, have never seen years like the last few, DeVogelaere said.

The Monterey Bay’s lack of resources can be hard to take note of. Whale-watching companies are celebrating a heyday. Last year, naturalists and tourists watched cetaceans swarm like never before. But whales form large congregations because of the scarcity of food, DeVogelaere said, and they’re forced to converge in the few nutrient-rich locations where they can find a meal.

The changing conditions offshore undoubtedly affect harbor seals, he added.

The harbor seal may be a distant cousin to the adventurous California sea lion and elephant seal, but it’s an entirely different animal. Harbor seals are incredibly loyal to their rocky homes, straying a mere mile or two to swim and feed. If warming coastal waters kill off their food supply, they’ll likely starve.

Mother harbor seals are taking an additional hit. During the pupping season last spring, “lots of the moms didn’t have enough milk and had to abandon pups on the beach,” said Thom Akeman, who has been watching his flippered neighbors sleep and romp along the Pacific Grove shores for 13 years.

Two years ago, female seals weaned 90 healthy pups at Hopkins Marine Station, the largest harbor seal rookery in Pacific Grove. This year, the colony had only 30 pups, many of which were born to mothers too malnourished to rear them.

During Bay Net’s Pacific Grove harbor seal census on Nov. 25, Akeman saw only nine baby seals at Hopkins. He suspects these are the last remaining pups in the colony.

The Pacific Grove harbor seal population is expected to recover, but scientists are unsure how long it will take. Their comeback depends on ocean temperatures cooling, and staying cool for a prolonged time, allowing the food web to prosper once again. But no one can say when, or if, the temperatures will stay low enough for this to happen, said Akeman and DeVogelaere.

The unpredictable effects of global climate change make it a guessing game.

“We’re in an uncontrolled experiment. We’re changing the atmosphere of the world and the chemistry of the oceans. No one has done this experiment before, so we’re really rolling the dice,” DeVogelaere said.

Fortunately for Pacific harbor seals, the local population decline is an isolated oddity. Throughout California, Oregon and Washington, the population is steadily rising. California is home to about 31,000 harbor seals, and many colonies in the Monterey Bay are stable or thriving.

The next Pacific Grove harbor seal count, conducted by the Akemans, is scheduled for late March, when the pupping season begins. The couple, who just began tallying the seals this year, now plan to count them three times a year — in the early spring, summer and fall. They’ll report their findings to NOAA and fellow Bay Net docents through emails and the general public with Facebook.

Teaching others about the environment and the ways to respect wildlife, which Bay Net docents aim to do, is important, DeVogelaere said. And environmental issues and awareness should be given the prominence and attention they deserve, he added.

“I wish people would care about them more,” DeVogelaere said. “They might be affecting the world for their children and their children’s children … But I think in general, people want to do the right thing, if they know what the right thing is. Education is the way to go.”

People look at a harbor seal haul at the beach at Hopkins Marine Station in Pacific Grove on Wednesday. (David Royal - Monterey Herald)People look at a harbor seal haul at the beach at Hopkins Marine Station in Pacific Grove on Wednesday. (David Royal – Monterey Herald)

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

Dec 1 2016

Millions of Sardines Cloud San Diego Coast

A large sardine shoal showed up off the coast of California.


View original article/video: http://abcnews.go.com/