Thirteen corporations control up to 40 per cent of world’s most valuable fisheries

A press release from Stockholm University: Just thirteen corporations control 19-40% of the largest and most valuable stocks and 11-16 % of the global marine catch, according to new research. These “keystone” corporations of the global seafood industry critically shape the future of marine ecosystems, but have yet to assume this responsibility at the global scale.

The new study, published in the journal PLOS ONE, makes an analogy between the largest companies in seafood industry and keystone species in ecological communities. Keystone species in nature have a profound effect on the structure and function of the ecosystem and disproportionately determine the prevalence and activities of other species. For example just a small number of sea otters can determine urchin numbers, or a few grey wolves determine the size of bison, deer or elk populations.

Likewise, the study found that the average annual revenues of the 160 largest companies in 2012 exhibit a distinct keystone pattern, where the top 10% account for 38 % of total revenues. The identified thirteen companies (box) shape very large marine ecosystems around the world and are involved in both wild capture fisheries and aquaculture, including whitefish, tuna, salmon, shellfish, fishmeal, fish oil, and aqua feeds. Their combined annual revenues correspond to 18% of the global value of seafood production in 2012 (US$ 252 billion).

This handful of corporations (representing 0.5% of 2250 registered fishing and aquaculture companies worldwide) dominate all parts of seafood
production, operate through an extensive global network of subsidiaries and are profoundly involved in fisheries and aquaculture decision-making. Such omnipotence represents both a challenge and an opportunity for the governance of global fisheries.

“The phenomenon of keystone actors is an increasingly important feature of our human-dominated world. Active leadership in sustainability initiatives by these corporations could result in a cascade through the entire seafood industry towards improved management of marine living resources and ecosystems,” says lead author Henrik Österblom, Deputy Science Director of the Stockholm Resilience Centre.

“Increasing demand for seafood has contributed to a global fisheries crisis, with consequences for marine ecosystems around the world,” Österblom adds. Existing analyses of global fisheries operations have, however, so far largely focused on the role of countries, rather than industry corporations....

A fishing vessel off the coast of Scotland in 1963, shot by Phillip Capper, Wikimedia Commons, under the Creative Commons Attribution 2.0 Generic license

High seas fishing ban could boost global catches, equality

A press release from the University of British Columbia: Closing the high seas to commercial fishing could distribute fisheries income more equitably among the world’s maritime nations, according to research from the University of British Columbia (UBC).

The analysis of fisheries data indicates that if increased spillover of fish stocks from protected international waters were to boost coastal catches by 18 per cent, current global catches would be maintained. When the researchers modelled less conservative estimates of stock spillover, catches in coastal waters surpassed current global levels.

“We should use international waters as the world’s fish bank,” says Rashid Sumaila, director of the UBC Fisheries Economics Research Unit and lead author of the study. “Restricting fisheries activities to coastal waters is economically and environmentally sensible, particularly as the industry faces diminishing returns.”

...The study also indicates that a high-seas moratorium would improve fisheries income distribution among maritime nations. Currently, 10 high seas fishing nations capture 71 per cent of the landed value of catches in international waters.

Under all scenarios considered by the researchers, European Member States, Group of Eight nations, and least developed fishing nations would benefit the most from a closure. Under a catch-neutral scenario, the United States, Guam and the United Kingdom would benefit the most, each with potential increases in landed values of more than $250 million (USD) per year. Canada would see an increase of $125 million (USD) per year....

Map of gains and losses from the proposed plan from the University of British Columbia website

Fishing quotas defy scientists’ advice

Fiona Harvey in the Guardian (UK): Britain’s fishermen will be allowed to increase their catch of cod and other key fish species next year after late-night wrangling between EU ministers in Brussels resulted in a new set of fishing quotas that flout scientific advice. The quota for cod catches for 2015 will increase by 5% on last year, though scientific advice suggested that it should be cut by 20%.

The UK’s fisheries minister, George Eustice, hailed the deal as a triumph for Britain’s dwi
ndling fishing fleets. He said: “Although these were difficult negotiations, I am pleased that we were able to secure the best possible deal to ensure sustainable fisheries and a strong UK fishing industry. While fishermen had feared there would be major cuts, we were able to keep the same quota as last year for many species, in addition to important increases to the North Sea cod and haddock quota, which will benefit Scottish fishermen.”

UK fishermen will also be allowed to catch 15% more prawns than last year and 15% more plaice in the North Sea, while the haddock catch has been increased by 6%. But in the Celtic Sea, fewer cod and haddock will be allowed to be caught – though the number is still more than scientists advised – and the number of sole to be caught in the Bristol and Eastern channels has been reduced.

Conservationists said the deal, reached after a day and a half of negotiations in Brussels, was not in line with what scientists had advised. After nearly four years of tense negotiations, the EU’s Common Fisheries Policy was finally reformed this year. In its new state, it is supposed to guarantee that fish stocks are managed at what scientists deem to be sustainable levels, known as the maximum sustainable yield.

Andrew Clayton, of the Pew Charitable Trusts, which advocates a sustainable fisheries policy, said: “After decades of failing to get to grips with overfishing, the new common fisheries policy was supposed to bind ministers to setting sustainable fishing limits this year. Instead, they have set a considerable number of [quotas] in excess of the level scientists advised, failing to meet the targets they set themselves for overfishing. These are weak decisions, jeopardising the livelihoods of fishermen and the sustainability of stocks.”...

A fishing trawler in front of the National Marine Aquarium in Plymouth, shot by Darren Rosson Darren Rosson, Wikimedia Commons via Geograph UK, under the Creative Commons 2.0 Generic license

210 million people benefit from mangroves-associated fisheries

Wetlands International: Some 210 million people live in low elevation areas within 10 km of mangroves and many of these directly benefit from mangrove-associated fisheries. Yet, these people are often unaware of the key role mangroves may play, especially if the associated fisheries are offshore.

A new study by Wetlands International, The Nature Conservancy and the University of Cambridge, launched today at World Fisheries Day, concludes that mangrove conservation and restoration in areas close to human populations will render the greatest return on investment with respect to enhancing fisheries.

The fisheries value of mangroves is site specific as it depends on how many fish a mangrove produces, how many fish are subsequently caught by humans, and then what the fisheries value is, both in economic terms, as a food supply or through the livelihoods that they support.

As demands for fish continues to rise with the increase of coastal populations and rapidly growing economies, understanding where mangrove-associated fish productivity is highest is critical. Well-known species that rely on mangroves in one way or another include crabs, prawns, mullet, herring, anchovy, snappers and groupers….

Mangroves in Cuba, shot by Manuel Dohmen, Wikimedia Commons, under the Creative Commons 3.0

A new way to track bigeye tuna

Janet Lathrop at UMassAmherst News & Media Relations: A first-of-its-kind study of bigeye tuna movements in the northwestern Atlantic Ocean led by Molly Lutcavage, director of the Large Pelagics Research Center at the University of Massachusetts Amherst, found among other things that these fish cover a wide geographical range with pronounced north-south movements from Georges Bank to the Brazilian shelf, and they favor a high-use area off Cape Hatteras southwest of Bermuda for foraging.

This NOAA-funded research, which used a new approach to study one of the most important commercial tuna species in the Atlantic, provides the longest available fishery-independent record of bigeye tuna movements to date. Data should help researchers to further characterize habitat use and assess the need for more monitoring in high-catch areas.

...Fisheries oceanographer Lutcavage says, “Although Atlantic bigeye tuna are delivering high prices to the U.S. commercial fleet and are highly sought by recreational fishermen and fishing tournaments, there’s been a surprising lack of scientific research on this species. And in contrast to the Pacific, where tuna fisheries programs have deployed over 400,000 tags over 25 years, the Atlantic lacks the fisheries infrastructure that would increase the odds of reco
vering tags. We have to rely on popup satellite tags that are fishery independent to make sure we get information back from the tuna.”

...Working with pelagic longline vessel captains Scott Drabinowicz and John Caldwell of the FV Eagle Eye II out of Fairhaven, Mass., Lutcavage, with LPRC colleagues Tim Lam and doctoral candidate Ben Galuardi, deployed 21 pop-up satellite archival tags (PSAT) on adult bigeye tuna between 2008 and 2010 in the northwest Atlantic. The sea captains fit tags on fish in good condition and return them to the sea. The PSATs were programmed to record relative light level, temperature and pressure (depth) every two minutes for eight or 12 months.

...Lam explains, “Bigeye tuna dive deeply, like clockwork, at dusk and dawn, making it hard to use light-based geolocation methods to estimate their daily locations. Here, we showcase a new positioning technique to get around the problem of low light levels at depth by using temperature and the bigeyes’ spatial ecology and movements in the western Atlantic. But there’s much more to learn.”

The authors hope their results will inform the International Commission for the Conservation of Atlantic Tuna’s upcoming tagging effort and assist ICCAT scientists as they plan new research to better understand the population....

Pelagic longline vessel Captain Scott Drabinowicz and crew preparing to deploy a tag from the deck of the FV Eagle Eye II. From the UMass Amherst website

Report supports shutdown of all high seas fisheries

A press release from the University of British Columbia: Fish and aquatic life living in the high seas are more valuable as a carbon sink than as food and should be better protected, according to research from the University of British Columbia.

The study found fish and aquatic life remove 1.5 billion tonnes of carbon dioxide from the atmosphere every year, a service valued at about $148 billion US. This dwarfs the $16 billion US paid for 10 million tonnes of fish caught on the high seas annually.

“Countries around the world are struggling to find cost effective ways to reduce their carbon emissions,” says Rashid Sumaila, director of the UBC Fisheries Economics Research Unit. “We’ve found that the high seas are a natural system that is doing a good job of it for free.”

Sumaila helped calculate the economic value of the carbon stored by life in the high seas by applying prices—which include the benefits of mitigating the costs of climate change–to the annual quantity of carbon absorbed.

The report argues that the high seas—defined as an area more than 200 nautical miles from any coast and outside of national jurisdiction–should be closed to all fishing as only one per cent of fish caught annually are exclusively found there.

“Keeping fish in the high seas gives us more value than catching them,” says Sumaila. “If we lose the life in the high seas, we’ll have to find another way to reduce emissions at a much higher cost.”...

NOAA image of a trawler off the coast of Alaska

Palau to focus on tourism, prohibit commercial fishing

Taipei Times via AP, United Nations: The president of Palau on Tuesday announced that his Pacific island nation will ban commercial fishing and become a marine sanctuary.

Palauan President Tommy Remengesau said in a keynote address to a UN meeting on “Healthy Oceans and Seas” that once current fishing contracts with Taiwan, Japan and some private companies expire, only fishing by island residents and tourists will be allowed in its 200 nautical mile (370.4km) exclusive economic zone.

Remengesau said establishing “a 100 percent marine sanctuary” will enable Palau to preserve “a pristine environment” and promote snorkeling, scuba diving and ecotourism as an alternative way to grow its economy. “It will make a difference if it’s just a matter of feeding ourselves and feeding the tourists,” he told a news conference. As it is right now, we’re feeding the tourist and ourselves plus millions of people outside the territory,” he said.

Palau’s population of about 20,000 people is spread across 250 islands. It shares maritime boundaries with Indonesia, the Philippines and Micronesia.

The country announced in 2009 it was creating the world’s first shark sanctuary by banning all commercial shark fishing in its territorial waters. It has also adopted the most restrictive law against bottom trawling. In 2012, its Rock Islands Southern Lagoon was named a UNESCO World Heritage site...

An aerial view of Peleliu in Palau, shot by US National Park Service 

Google Earth enables remote tracking of fish catches

Ola Al-Ghazawy in SciDev.net: Persian Gulf governments could use Google’s free global satellite imaging program to better monitor and control fishing in their waters, say experts. Their comments follow a study that used Google Earth to uncover huge discrepancies between reported and observed fish catches in the region.

The study, which tracked fishing from space, found that actual catches taken from Persian Gulf fisheries could be six times greater than the official numbers the Gulf states reported to the UN’s Food and Agriculture Organization (FAO).

Researchers from the University of British Columbia (UBC) in Canada used Google Earth to count, for the first time, intertidal fishing weirs — an old technique used to catch fish by placing obstructions across tidal waters. They examined six countries on the Persian Gulf: Bahrain, Iran, Kuwait, Qatar, Saudi Arabia and the United Arab Emirates.

The study, which was published last year (27 November) in ICES Journal of Marine Science, highlights the unreliability of some countries’ official reports to the FAO. It found 1,900 weirs were operational in the countries surveyed in 2005 and estimated their combined production that year at approximately 31,000 tonnes of fish — more than six times the combined total of 5,000 tonnes the six countries reported to the FAO that year.

“Underreporting fish catches can jeopardise a country’s food security and economy, not to mention impact entire marine ecosystems,” says Dalal Al-Abdulrazzak, the study’s first author...

NOAA: Coastal ocean aquaculture can be environmentally sustainable

A press release from NOAA: Specific types of fish farming can be accomplished with minimal or no harm to the coastal ocean environment as long as proper planning and safeguards are in place, according to a new report from researchers at NOAA’s National Ocean Service.

The study, led by scientists at National Ocean Service’s National Centers for Coastal Ocean Science (NCCOS), evaluated the environmental effects of finfish aquaculture, including interactions with water quality, benthic habitats, and marine life across various farming practices and habitat types.

“We did this study because of concerns that putting marine finfish farms in the coastal ocean could have adverse effects on the environment,” said Dr. James Morris, NCCOS ecologist. “We found that, in cases where farms are appropriately sited and responsibly managed, impacts to the environment are minimal to non-existent.”

“This report provides coastal and farm managers with a global perspective on a range of potential environmental effects and their relative intensity,” said Dr. Michael Rubino, director of NOAA Fisheries Office of Aquaculture. “It is a tool that can be used when evaluating proposed or operational farming sites and gives them a factual basis to make decisions.”

In the report, scientists said that continued development of regional best-management practices and standardized protocols for environmental monitoring are key needs for aquaculture managers. As aquaculture development increases in the coastal ocean, the ability to forecast immediate or long-term environmental concerns will provide confidence to coastal managers and the public.

“This report contributes to the growing body of evidence supporting marine aquaculture as a sustainable source of safe, healthy and local seafood that supports jobs in coastal communities,” said Sam Rauch, acting assistant NOAA administrator for NOAA Fisheries...

Net pen aquaculture in deep coastal waters, photo by NOAA

2013 Ocean Health Index shows food provision remains an area of great concern

A press release from UC Santa Barbara: In the 2013 Ocean Health Index (OHI) –– an annual assessment of ocean health led by Ben Halpern, a research associate at UC Santa Barbara's National Center for Ecological Analysis and Synthesis (NCEAS) and professor at the Bren School of Environmental Science & Management –– scientists point to food provision as the factor that continues to require serious attention.

The OHI defines a healthy ocean as one that sustainably delivers a range of benefits to people now and in the future based on 10 diverse public goals. The 2013 score of 65 out of 100 demonstrates the ongoing need for more effective management of this precious resource.

"I'm encouraged because people, organizations and governments are paying attention to the Ocean Health Index and what they can learn from it," Halpern said. "Not only has the OHI been adopted as an indicator to gauge how well countries are meeting their biodiversity conservation targets, but it is beginning to inform the United Nations World Ocean Assessment and was named by the World Economic Forum as one of two endorsed tools for helping achieve sustainable oceans."

Goal scores out of a possible 100 for categories that make up the OHI ranged from a low of 31 for natural products to a high of 95 for artisanal fishing opportunities. Other categories include food provision (33), carbon storage (74), coastal protection (69), coastal livelihoods and economies (82), tourism and recreation (39), sense of place (60), clean waters (78) and biodiversity (85).

With a score of only 33 out of 100, food production from wild harvest and mariculture (cultivation of marine organisms in the open ocean) was the second-lowest-scoring goal and one of the most important resources from the sea for people around the world. A score of 100 is given for wild-caught fisheries if the biomass of landed stocks at sea is within ±5 percent of a buffered amount below the biomass that can deliver maximum sustainable yield. For mariculture, the number of tonnes of product per coastal inhabitant living within 31 miles of the coast is calculated for each country, and all countries above the 95th percentile receive scores of 100. Countries that have never had mariculture are not scored...

Map from the UC Santa Barbara website. The higher the number, the healthier the ocean

Researchers discover early-warning system to prevent fishery collapse

University of Minnesota News: Threats from overfishing can be detected early enough to save fisheries-- and livelihoods --with minimal adjustments in harvesting practices, a new study by researchers in the University of Minnesota’s College of Biological Sciences shows. The work indicates that a healthy fishery can be maintained the way a skillful captain steers an oil tanker: by small course corrections that prevent disaster far ahead.

The study, by Ecology, Evolution and Behavior (EEB) graduate student Matt Burgess and co-advisors Stephen Polasky (EEB and Applied Economics in the College of Food, Agricultural and Natural Resource Sciences) and David Tilman (EEB), was published on September 16 in the Early Edition of Proceedings of the National Academy of Sciences USA. Specifically, the work demonstrates how extinction and overfishing threats from multispecies fisheries can be identified decades before valuable species are over-harvested and populations decline.

Most of the world’s large fisheries use nets or lines with multiple hooks, which catch multiple species simultaneously and have serious ecological consequences. Past population declines and current increases in harvest rates can be used to assess current threats of overfishing and extinction, but this approach doesn’t apply to future threats. By predicting future threats, the researchers’ new method would enable conservation measures to prevent overfishing and extinction.

..."The data we collect includes estimates of the relative population sizes, catch rates and the growth rates of different fish populations," Burgess says. "This index uses what we know about what tends to happen to economically important fish to predict the fate of other species caught along with them."

The approach was tested on eight Pacific tuna and billfish populations; four of which have been identified recently by conventional methods as in decline and threatened with overfishing.  The study found that the severe depletion of all four populations could have been predicted in the 1950s using the Eventual Threat Index.  These results demonstrate that species threatened by human harvesting can be identified much earlier, providing time for adjustments in harvesting practices before consequences become severe and fishery closures or other socioeconomically disruptive interventions are required to protect species.  Burgess says the index is easy and inexpensive to use. He hopes fisheries will adopt it soon....

A large lift net in Bengali-Veshal, shot by Balaram Mahalder, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

French oysters hit as mystery killer spreads

John Lichfield in the Independent (UK): A mysterious ailment is killing up to 80 per cent of adult oysters in shell fisheries around the French coast this summer, threatening an industry already weakened by a succession of crises. The bizarre weather – weeks of rain and cold followed by tropical temperatures – is officially blamed for the sudden death of scores of thousands of oysters in south-western France, Brittany and Normandy.

But producers fear that an unknown disease may be devastating oyster beds, stricken since 2008 by a virus which massacres baby oysters. French output has been slashed by a third in the past four years.

"Some people are having to ration their sales," said Olivier Laban, president of the association of oyster producers in the Bay of Arcachon, near Bordeaux. "We were already producing relatively few oysters because of the deaths of juveniles in past years. Prices are very high and cannot really go higher."

The sudden death of adult oysters, just before they go on sale, is even more calamitous. "It means three years of work wiped out overnight," said Laurent Champeau, president of the shellfish producers in the La Rochelle area. "Our margin for manoeuvre is already practically nothing."

The demise of 15 to 80 per cent of the two- to three-year-old oysters in Arcachon, Poitou-Charentes, northern Brittany and Normandy may be caused by the strange weather pattern this year, experts believe. Incessant rain from May to early July reduced the salt content of the water in the mud flats where the oysters are reared. The heat wave since mid-July has further weakened the shellfish, making them vulnerable to disease...

An aerial view of Arcachon in France, shot by Larrousiney, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

As dams loom, Mekong fishermen fear for their future

Terra Daily via AFP: The waters of the mighty Mekong have sustained generations of families but nowadays its fishermen often find their nets empty and fear hydropower mega-dams will destroy their livelihoods.

...For many in the community, the reason lies upriver in the Chinese province of Yunnan where dams on the upper reaches of the river disturb the delicate cycle of nature. "Usually the water would rise (and fall) with the seasons," said fisherman Decha Chaiwong, 48. Now it ebbs and flows depending on whether the dams are open or closed, he said.

...Today a new threat looms downstream in neighbouring Laos. The Xayaburi hydropower project is one of 11 planned on the lower Mekong, raising worries for the future of the 60 million people in the region estimated to depend on the river in some way...

Scoop net fishing on the Mekong River, shot by Ricardo Hurtubia, Wikimedia Commons via Flickr, under the Creative Commons Attribution 2.0 Generic license

Changing sea surface temperatures and water circulation patterns affecting food supply for young Atlantic cod

NOAA's Northeast Fisheries Science Center: Changing ocean water temperatures and circulation patterns have profoundly affected key Northeast U.S. Continental Shelf zooplankton species in recent decades, and may be influencing the recovery of Atlantic cod and other fish stocks in the region.

NOAA researcher Kevin Friedland and colleagues looked at the distribution and abundance of important zooplankton species, sea surface water temperatures, and cod abundance. They found that zooplankton species critical for the survival of Atlantic cod larvae have declined in abundance in the same areas where Atlantic cod stocks have struggled to rebuild after an extended period of overfishing.

“Temperature is a governing factor in the growth, reproduction and distribution of marine organisms. Shifting temperature distributions, whether triggered by natural or human factors, can cause the redistribution of plankton communities on regional and basin-wide scales,” said Friedland, lead author on the study and a scientist at NOAA's Northeast Fisheries Science Center (NEFSC).

The change in thermal habitats has had biological consequences on multiple levels in the food chain, according to the study in press in the journal Progress in Oceanography (available online).

“The geographic and depth distributions of fish and shellfish populations can also change based on their preferred thermal habitats. Future changes in thermal conditions are expected to lead to further shifts in the distributional ranges of species by, in many cases, the loss and gain of local populations,” said Friedland.

Friedland and his colleagues found that ocean water temperatures of the Northeast Continental Shelf have increased in recent decades, but these changes have not been uniform over the entire ecosystem.  Warm water habitats (16 to 27 C, 60 to 80 F) have increased and cool water habitats (5 to 15 C, 41 to 59 F), historically the core habitats in the ecosystem, have declined; however, the coldest habitats in the ecosystem (1-4 C, 34-39 F) have either stayed the same or increased slightly during the study period 1982-2011. This discontinuity is attributed to changes in circulation in the northern Gulf of Maine associated with the Labrador Current....

Eight boxes represent index areas for long-term sea surface temperature (SST) trends for the Northeast Shelf ecosystem; annual mean, minimum, and maximum SST for the period 1854-2011 was calculated for the index area. The grey shaded area of the Northeast Shelf was used in the calculation of thermal habitat distribution for the ecosystem. Credit: Kevin Friedland, NEFSC/NOAA

Climate change to cut Philippines fish catch by 50%

Malaya Business Insight: The Philippines will have to prepare for a 50 percent drop in fish catch and the huge risks storms will have on informal settlements and coastal communities due to climate change.  The World Bank said that fish catch in southern Philippines will be cut by half  during the 2050s, due to warmer sea temperatures and ocean acidification.

“Many South East Asian countries are already taking concerted actions to address the impacts of climate change, but this report tells us that we need to do much more,” Axel van Trotsenburg, World Bank Vice President for East Asia and Pacific, said. “We need to both intensify and accelerate these actions to reduce the ever-increasing vulnerability of populations to climate risk, especially the poor and vulnerable,” he added.

The World Bank said that in the Philippines, the biggest risks are due to more severe impacts storms will have on informal settlements and coastal communities. “The Bank is working with the Government of the Philippines to enhance the country’s capacity to deal with climate impacts as well as help ensure its overall national public expenditure is appropriately targeted to deal with these challenges,” the World Bank said.

“Together with other development partners, the Bank is also helping in the preparations for priority projects that aim to improve flood management and resilience in Metro Manila,” it added....

Traditional boat building in the Philippines, shot by Paul Shaffner, Wikimedia Commons via Flickr,  under the Creative Commons Attribution 2.0 Generic license

Why we need to put the fish back into fisheries

Space Daily via SPX: Overfishing has reduced fish populations and biodiversity across much of the world's oceans. In response, fisheries are increasingly reliant on a handful of highly valuable shellfish. However, new research by the University of York shows this approach to be extremely risky.

The research, published in the journal Fish and Fisheries, shows that traditional fisheries targeting large predators such as cod and haddock, have declined over the past hundred years. In their place, catches of shellfish such as prawns, scallops and lobsters have rocketed as they begin to thrive in unnaturally predator-low environments often degraded by the passage of trawls and dredges.

In many places, including the UK, shellfish are now the most valuable marine resource. The research by the Environment

Department at York suggests that although a shellfish-dominated ecosystem appears beneficial from an economic perspective, it is highly risky. Like simplified agricultural systems, these shellfisheries are unstable in the long-term and at great risk of collapse from disease, species invasions and climate change.

Warming and acidification of our oceans due to greenhouse gas emissions is expected to affect shellfish worst. Ocean acidification, in particular, will limit the ability of scallops and other shellfish to form proper shells, and lead to widespread mortality....

Shellfish on a beach, shot by Titus Tscharntke, Wikimedia Commons, public domain

Boom in jellyfish: overfishing called into question

Science Daily: Will we soon be forced to eat jellyfish? Since the beginning of the 2000s, these gelatinous creatures have invaded many of the world's seas, like the Japan Sea, the Black Sea, the Mediterranean Sea, etc. Is it a cyclic phenomenon, caused by changes in marine currents or even global warming? Until now, the causes remained unknown. A new study conducted by IRD researchers and its partners, published in Bulletin of Marine Science, exposes overfishing as the main factor.

Jellyfish predators, such as tuna and sea turtles, are disappearing due to overfishing. However, jellyfish are primarily taking advantage of the overfishing of small pelagic fish. Just like these cnidarians, sardines, herring, anchovies and more feed off zooplankton. Thus, they represent their main competition for food. In areas where too many of these fish are caught, they free up an ecological niche. Jellyfish now have free rein and can thrive. Furthermore, small fish eat the eggs and larvae of jellyfish. Therefore, under normal conditions, they regulate the population. In their absence, there is nothing to stop the proliferation of these gelatinous creatures.

In order to demonstrate the major role played by overfishing, researchers compared two ecosystems belonging to the same ocean current, the Benguela, which flows along the south of Africa. The first ecosystem is located off the coast of Namibia. Here, fish stock management measures are not very restrictive. The stocks are barely restored before fishing activities start up again. Jellyfish are currently colonising these coastal waters. The second ecosystem is located 1,000 km further south, off the coast of South Africa. Here, the opposite is true: fishing has been tightly controlled for 60 years. The jellyfish population has not increased....

A jellyfish at the Kyoto Aquarium, shot by Oilstreet, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license 

Sea surface temperatures reach highest level in 150 years on northeastern US continental shelf

NOAA's Northeast Fisheries Science Center: Sea surface temperatures in the Northeast Shelf Large Marine Ecosystem during 2012 were the highest recorded in 150 years, according to the latest Ecosystem Advisory issued by NOAA’s Northeast Fisheries Science Center (NEFSC). These high sea surface temperatures (SSTs) are the latest in a trend of above average temperature seen during the spring and summer seasons, and part of a pattern of elevated temperatures occurring in the Northwest Atlantic, but not seen elsewhere in the ocean basin over the past century. The advisory reports on conditions in the second half of 2012.

Sea surface temperature for the Northeast Shelf Ecosystem reached a record high of 14 degrees Celsius (57.2°F) in 2012, exceeding the previous record high in 1951. Average SST has typically been lower than 12.4 C (54.3 F) over the past three decades.

Sea surface temperature in the region is based on both contemporary satellite remote-sensing data and long-term ship-board measurements, with historical SST conditions based on ship-board measurements dating back to 1854. The temperature increase in 2012 was the highest jump in temperature seen in the time series and one of only five times temperature has changed by more than 1 C (1.8 F).

The Northeast Shelf’s warm water thermal habitat was also at a record high level during 2012, while cold water habitat was at a record low level. Early winter mixing of the water column went to extreme depths, which will impact the spring 2013 plankton bloom. Mixing redistributes nutrients and affects stratification of the water column as the bloom develops.

Temperature is also affecting distributions of fish and shellfish on the Northeast Shelf. The advisory provides data on changes in distribution, or shifts in the center of the population, of seven key fishery species over time. The four southern species - black sea bass, summer flounder, longfin squid and butterfish - all showed a northeastward or upshelf shift. American lobster has shifted upshelf over time but at a slower rate than the southern species. Atlantic cod and haddock have shifted downshelf.”...

The four subregions of the Northeast Shelf Large Marine Ecosystem, which extends from Cape Hatteras, N.C. to the Gulf of Maine. MAB is the Mid-Atlantic Bight, SNE is Southern New England, GB is Georges Bank, and GOM is the Gulf of Maine. Credit: NOAA

Climate change a 'mixed bag' for Pacific Island fisheries and aquaculture

A press release from the Australian Institute of Marine Science: An international, multidisciplinary team of scientists have combined their expertise to make projections for the future of tropical Pacific fisheries and aquaculture in the 21st century. Their research suggests that predicted climate change in the region will create winners and losers in both fisheries and aquaculture, requiring adaptation by many Pacific Island nations.

Dr Janice Lough, Senior Principal Research Scientist of the Australian Institute of Marine Science (AIMS) was one of the team to collaborate on the project, co-ordinated through the Secretariat of the Pacific Community and part-funded by AusAID. As a specialist in marine climate projections and their consequences for human activities on coral reef ecosystems, Dr Lough provided insights into observed and possible future climates of the tropical Pacific.

"It was extremely rewarding to be a part of this important project which is ultimately about assisting people and governments throughout the tropical Pacific in planning for future food security and economic prosperity," says Dr Lough. "Fisheries and aquaculture are key economic and subsistence industries for Pacific Island nations and here we attempted to factor climate change models into the long-term productivity of the resources that underpin these industries, many of which are already undergoing changes due to increasing population pressures."

Published today in the prestigious scientific journal, Nature Climate Change, the paper provides comprehensive coverage of the projected climate changes in the tropical Pacific, including regional warming and reduced salinity, increasing rainfall, more intense tropical cyclones and shifting ocean currents. These changes will have knock-on effects for feeding and spawning grounds for key oceanic fisheries, such as skipjack tuna, which is predicted to shift progressively eastwards.

Coastal fisheries in the tropics rely on the coral reefs, mangroves and seagrasses that line their shores and the forecast climate change is expected to intensify the degradation many of these habitats are already experiencing. For example, coral bleaching, powerful cyclones and rising sea levels will reduce the size and complexity of reefs leading to declines in coral reef fisheries....

Coral reefs near Enderbury Island, Phoenix Islands Protected Area (PIPA) near Kiribati, shot by Dr. Randi Rotjan, New England Aquarium. www.neaq.org, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

Fishers near marine protected areas go farther for catch but fare well

Space Daily via SPX: Fishers near marine protected areas end up traveling farther to catch fish but maintain their social and economic well-being, according to a study by fisheries scientists at Washington State University and in Hawaii.

The study, reported in the journal Biological Conservation, is one of the first to look closely at how protected areas in small nearshore fisheries can affect where fishers operate on the ocean and, as a consequence, their livelihood.

"Where MPAs are located in relation to how fishers operate on the seascape is critical to understand for fisheries management and this is an important lesson to draw from this study," said Todd Stevenson, the paper's lead author, who did the research as part of his WSU doctorate.

Marine protected areas have become a cornerstone of ocean conservation, setting aside specific waters to preserve and manage vulnerable resources like declining fish stocks. In theory, the MPAs will provide a refuge in which fish can breed and help replenish nearby, open areas with their offspring. Nearly 6,000 MPAs have been set up around the world, according to a 2010 report by the International Union for Conservation of Nature and Natural Resources....

Central California marine sanctuaries, from NOAA