Overfishing and Global Warming Killing Billfish and Tuna

ScienceDaily — Billfish and tuna, important commercial and recreational fish species, may be more vulnerable to fishing pressure because of shrinking habitat, according to a new study published by scientists from NOAA, The Billfish Foundation, and University of Miami Rosenstiel School of Marine and Atmospheric Science.

An expanding zone of low oxygen, known as a hypoxic zone, in the Atlantic Ocean is encroaching upon these species' preferred oxygen-abundant habitat, forcing them into shallower waters where they are more likely to be caught.

During the study, published recently in the journal Fisheries Oceanography, scientists tagged 79 sailfish and blue marlin with satellite tracking devices in the western North Atlantic, off south Florida and the Caribbean; and eastern tropical Atlantic, off the coast of West Africa. The pop off archival satellite tags monitored horizontal and vertical movement patterns. Researchers confirmed that billfish prefer oxygen rich waters closer to the surface and will actively avoid waters low in oxygen.

While these hypoxic zones occur naturally in many areas of the world's tropical and equatorial oceans, scientists are concerned because these zones are expanding and occurring closer to the sea surface, and are expected to continue to grow as sea temperatures rise.

"The hypoxic zone off West Africa, which covers virtually all the equatorial waters in the Atlantic Ocean, is roughly the size of the continental United States, and it's growing," said Dr. Eric D. Prince, NOAA's Fisheries Service research fishery biologist. "With the current cycle of climate change and accelerated global warming, we expect the size of this zone to increase, further reducing the available habitat for these fish."

Less available habitat can lead to more fish being caught since the fish are concentrated near the surface. Higher catch rates from these areas may give the false appearance of more abundant fish stocks. The shrinking availability of habitat and resulting increases to catch rates are important factors for scientists to consider when doing population assessments.

Researchers forecast that climate change and its associated rise in ocean temperatures will further increase the expansion of hypoxic zones in the world's oceans. As water temperature increases, the amount of oxygen dissolved in water decreases, further squeezing billfish into dwindling available habitat and exposing them to even higher levels of exploitation.

Source: http://www.sciencedaily.com/releases/2010/12/101222162402.htm

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Oh! Canada! Study: Fishing Allowed In 99% of MPAs On Canada's Pacific Coast

Kim Wright, Marine Planning and Protected Areas Campaign Manager for Living Oceans Society. credit Living Oceans


VANCOUVER, British Columbia -- Fishing is allowed in all but one percent of Marine Protected Areas (MPA) on Canada's Pacific coast, according to a study conducted by Living Oceans Society and published in Marine Policy this month. This is in spite of the fact that over half of the MPAs are officially rated as "strictly protected" and are intended to prohibit all fishing.

"Marine Protected Areas should be safe havens where species can regenerate, but the great majority of our MPAs are really just paper parks that offer almost nothing in the way of ocean conservation or sustainable fisheries," says Kim Wright, Living Oceans Society's Marine Planning and Protected Areas Campaign Manager.


To build an effective network of MPAs, federal, provincial and municipal government agencies that designate MPAs need to ensure that the appropriate fishing closures are put in place by Fisheries and Oceans Canada (DFO). The Marine Policy article, Commercial Fisheries Closures in Marine Protected Areas on Canada's Pacific Coast: The Exception, not the Rule, reveals all levels of government are failing to coordinate their efforts and provide real protection for the ocean ecosystem.

Dr. Isabelle Coté, a Marine Protected Area specialist and professor at Simon Fraser University says that this study emphasizes the need to improve our network of MPAs if we want to reap the benefits. "Marine reserves, in which no fishing is permitted, increase the abundance and diversity of marine life within their boundaries," says Coté. "This study shows that the MPAs on Canada's Pacific coast are less likely to show the same positive effects."

Living Oceans Society is calling on the federal and provincial governments to address this issue coast wide, starting with the region known as the Pacific North Coast Integrated Management Area (PNCIMA) which extends from Vancouver Island north to the Alaska Border. The federal government, First Nations governments and stakeholders are currently working together to develop a marine plan for this region. According to Living Oceans Society, this is the perfect opportunity for all parties to work together to upgrade and improve the existing network of MPAs.

This will also help Canada live up to its international commitment, through the Convention on Biological Diversity, to build a network of MPAs by 2012 that encompasses 10 percent of every habitat type globally.

"As the nation with the longest coastline in the world, it is shocking so few MPAs exist and that fishing is allowed in almost all of them, including those classified as strictly protected," says Wright.

Source: http://www.underwatertimes.com/news.php?article_id=17509610384

What YOU can do:
Contact Fisheries and Oceans Pacific offices and encourage them to enforce MPAs. Respectfully ask that these areas be protected according to the committements the Canadian government set forth through the Convention on Biological Diversity:

http://www.dfo-mpo.gc.ca/Contact-eng.htm

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Slipped Through the Nets. EU misses target by more than 30 years.

ScienceDaily — At the Development Summit in Johannesburg in 2002, the European countries agreed to rebuild their fish stocks to levels that can produce the maximum sustainable yield, no later than 2015. According to scientists of the Excellence Cluster "Future Ocean," that goal is already out of reach: Of 54 analysed stocks, only saithe, western horse mackerel and Baltic sprat have a sufficiently large stock size and are fished at a sustainable rate. The state of 12 stocks, including North Sea cod, plaice and halibut, is so bad that they can not recover sufficiently until 2015, even if all fishing was halted. Other stocks could reach the target if fishing pressure was reduced substantially, but that has not happened so far.

These results were published by Dr. Rainer Froese, Leibniz Institute of Marine Sciences (IFM-GEOMAR) und Prof. Dr. Alexander Proelß, Walter-Schücking-Institute of International Law of the University of Kiel, in the journal Fish and Fisheries. The German scientists, both members of the interdisciplinary Excellence Cluster "Future Ocean," point out that the continuous overfishing of European stocks constitutes a breach of the precautionary principle, which is a binding principle of Community law.

"The precautionary principle is a binding legal principle for the organs of the European Commission and for the Council of Ministers. The current practice of continuous overfishing violates international law as well as Community law," says Prof. Dr. Alexander Proelß, expert of international law at the Walter-Schücking-Institute.

The obligation to manage fish stocks such that they can produce the maximum sustainable yield is part of the Law of the Sea (UNCLOS) of 1982, which entered into force in 1994. In the "Johannesburg Plan of Implementation" (2002), the European Union as well as Norway, Russia and Iceland, agreed to rebuild their fish stocks to the level that can produce the maximum sustainable yield, no later than 2015. "Until now, the provisions of the Law of the Sea have not been introduced into national law, and the plan of implementation had no visible impact on European fisheries management," says Proelß.

On the contrary: the fishing quotas for 2010 decreed by the Council of Ministers again exceed by far the catches that would allow the rebuilding of the stocks. "If this practice continues, Europe will miss by more than 30 years the goal that it has propagated," says Dr. Rainer Froese, fisheries biologist at the Kiel Leibniz Institute of Marine Sciences (IFM-GEOMAR).

Yet, catches from sustainably managed stocks could be substantially higher. "Our analysis suggests that landings could be 79% higher if stocks had been managed according to the international agreements," says Froese. "However, in European waters stocks are intentionally managed such that they stay close to the brink of collapse. This policy makes no sense from an ecological or economic point of view."

Source: http://www.sciencedaily.com/releases/2010/01/100121155224.htm

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Slipped Through the Net: Europe Misses by More Than 30 Years the International Goal of Rebuilding Its Fish Stocks

ScienceDaily — At the Development Summit in Johannesburg in 2002, the European countries agreed to rebuild their fish stocks to levels that can produce the maximum sustainable yield, no later than 2015. According to scientists of the Excellence Cluster "Future Ocean," that goal is already out of reach: Of 54 analysed stocks, only saithe, western horse mackerel and Baltic sprat have a sufficiently large stock size and are fished at a sustainable rate. The state of 12 stocks, including North Sea cod, plaice and halibut, is so bad that they can not recover sufficiently until 2015, even if all fishing was halted. Other stocks could reach the target if fishing pressure was reduced substantially, but that has not happened so far.

These results were published by Dr. Rainer Froese, Leibniz Institute of Marine Sciences (IFM-GEOMAR) und Prof. Dr. Alexander Proelß, Walter-Schücking-Institute of International Law of the University of Kiel, in the journal Fish and Fisheries. The German scientists, both members of the interdisciplinary Excellence Cluster "Future Ocean," point out that the continuous overfishing of European stocks constitutes a breach of the precautionary principle, which is a binding principle of Community law.

"The precautionary principle is a binding legal principle for the organs of the European Commission and for the Council of Ministers. The current practice of continuous overfishing violates international law as well as Community law," says Prof. Dr. Alexander Proelß, expert of international law at the Walter-Schücking-Institute.

The obligation to manage fish stocks such that they can produce the maximum sustainable yield is part of the Law of the Sea (UNCLOS) of 1982, which entered into force in 1994. In the "Johannesburg Plan of Implementation" (2002), the European Union as well as Norway, Russia and Iceland, agreed to rebuild their fish stocks to the level that can produce the maximum sustainable yield, no later than 2015. "Until now, the provisions of the Law of the Sea have not been introduced into national law, and the plan of implementation had no visible impact on European fisheries management," says Proelß.

On the contrary: the fishing quotas for 2010 decreed by the Council of Ministers again exceed by far the catches that would allow the rebuilding of the stocks. "If this practice continues, Europe will miss by more than 30 years the goal that it has propagated," says Dr. Rainer Froese, fisheries biologist at the Kiel Leibniz Institute of Marine Sciences (IFM-GEOMAR).

Yet, catches from sustainably managed stocks could be substantially higher. "Our analysis suggests that landings could be 79% higher if stocks had been managed according to the international agreements," says Froese. "However, in European waters stocks are intentionally managed such that they stay close to the brink of collapse. This policy makes no sense from an ecological or economic point of view."

Source: http://www.sciencedaily.com/releases/2010/01/100121155224.htm

---

About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Commercial Fishing Endangers Dolphin Populations, New Study Finds

ScienceDaily — Extensive commercial fishing endangers dolphin populations in the Mediterranean. This has been shown in a new study carried out at the University of Haifa's Department of Maritime Civilizations. "Unfortunately, we turn our backs to the sea and do not give much consideration to our marine neighbors," states researcher Dr. Aviad Scheinin.

The study, which was supervised by Prof. Ehud Spanier and Dr. Dan Kerem, examined the competition between the two top predators along the Mediterranean coast of Israel: the Common Bottlenose Dolphin (Tursiops truncatus) and bottom trawlers. (Trawling is the principal type of commercial fishing in Israel and involves dragging a large fishing net through the water, close to the sea floor, from the back of a boat.) These two predators off the coast of Israel trap similar types of fish near the sea floor, so the researchers decided to examine the nature of the competition between the two.

Commercial trawling in the Mediterranean off the coast of Israel targets codfish, red mullet and sole, three commercial and sought-after types of fish. The Department of Fisheries in Israel's Ministry of Agriculture has data showing that over the years the amount of fish from the sea floor looted by Israel's commercial trawling is larger than the amount of fish that nature provides, indicating that the sea floor fish population dropped between the years 1949 and 2006.

Would this decline in fish supply necessarily cause direct harm to the dolphins, seeing as their diet might also include other types of fish? In order to verify this, the researcher examined the contents of the stomachs of 26 dolphins that died and landed on the beach, or that had been caught by mistake. He also examined the behavior of living dolphins by carrying out 232 marine surveys over more than 3,000 km. along the central coast of Israel. The dolphins' stomachs contained mainly non-commercialized fish, suggesting that they perhaps do not compete directly with the commercial trawlers, and that the commercial fishing does not directly affect the dolphins' nutrition.

The living dolphins' behavior, on the other hand, draws an entirely different picture. According to Dr. Scheinin, most of the dolphins were observed around the trawling boats: the chances of observing a school of dolphins near a trawler is ten times higher than in the open sea. This is because the trawler serves as a "feeding station" for the dolphins: there they are not able to feed from the more expensive loot caught in the nets, but they are able to enjoy schools of other types of fish that swim around the trawler. "The problem is that this type of fishing endangers the dolphins. Eight dolphins die each year off the coast of Israel on average, and of those, four die after having been mistakenly caught in trawling nets. Seeing as many studies have proven the high intelligence of the dolphin, it is clear that these sea mammals are aware of this danger, but are left with little choice due to their need to search for food around the trawlers due to the scarcity of other food sources," Dr. Scheinin explains.

This conclusion is reinforced by the suckling female dolphins. These dolphins require larger quantities of food than usual, and despite the risk for the younger and much less experienced dolphins that swim by their side, all of the suckling dolphins have been observed significantly more frequently around the trawlers. This indicates that they could not obtain enough food in other places.

The dolphins off the coast of Israel spend most of their time in search of food while their mates in other areas in the world are far busier with social activities. This fact is yet another contributing factor to the assumption that they suffer a deficiency in food resources.

The present study illustrates, for the first time, the characteristics of the dolphins inhabiting the sea region off the Mediterranean coast of Israel. This dolphin population is stable and at any given time can be counted at about 350 dolphins. Of these, the researchers are personally familiar with 150 dolphins -- on a first name basis -- which can be identified by the dorsal fin, the dolphin's fingerprint. Forty of these are seen repeatedly and are permanent inhabitants of opposite the coast of Israel. "There is a stable dolphin population off the shores of Israel, and any resolution concerning the sea must also consider the dolphins. So as to preserve this population we must declare extensive marine nature reserves, so as to regulate fishing and bring an end to sea pollution. Regrettably, we are not considerate enough of the dolphins," concludes Dr. Scheinin.

Source: http://www.sciencedaily.com/releases/2010/02/100204101813.htm

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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France backs bluefin tuna ban but after delay

France, Italy and Spain account for half of the world's total allowable catch of bluefin tuna.
PARIS (Reuters) - France said on Wednesday it would support a ban on global trade in bluefin tuna, but after an 18-month delay, bowing to pressure from the fishing lobby to hold off an immediate decision on the giant fish.

Environmentalists such as Greenpeace called the delay "absurd" and said it could lead to the extinction of the fish that is prized by sushi lovers.

"Asking for 18 months to implement this measure equates to waiting until there is no more bluefin tuna before acting," Greenpeace said in a statement. "The government is buying peace with the fishermen at a time of regional elections."

Monaco has proposed protecting bluefin tuna, which can fetch up to $100,000 in Japan, by listing it under appendix I of the Convention on International Trade in Endangered Species (CITES).

France did not expect a ban to come into effect before September 2011, Environment Minister Jean-Louis Borloo said on Wednesday, adding the CITES committee needed the results of a scientific study on stocks before taking a decision in July 2011.

"There is still powerful international lobbying from a big country, which has allies," he said, referring to Japan, where 80 percent of the catch is exported.

The European Union failed to make progress on bluefin tuna last year, with Greek Environment Commissioner Stavros Dimas and Maltese Fisheries Commissioner Joe Borg deadlocked over how far the EU should go to protect the fish.

EU diplomats expect to see faster progress this year under newly nominated Greek Fisheries Commissioner Maria Damanaki.

French Agriculture Minister Bruno Le Maire said on Wednesday that France would call on the European Commission to compensate fishermen for lost revenues should the ban be imposed.

Fishermen's representatives called the French position "incoherent" ahead of the regional elections in March.

"The government is really in a messy position," said Francois Wendling, head of a fishermen's trade association in Sete in southern France.

"If waiting for scientific studies is so important, why is the government giving a position now? This is purely political."

President Nicolas Sarkozy said last year he favoured a clear trade ban on bluefin tuna.

Asked if the government would stand by its position if fishermen decided to block ports as they did in Marseille last April, Le Maire said:

"French fishermen are reasonable people. But what makes them angry is when rules do not apply to everyone. France will ask for reinforced sanctions against countries which do not respect them (bluefin tuna fishing quotas)."

There are about 200 tuna boats in France, but only 28 are so-called "purse-seiners," 40-meter long high-tech boats which account for 90 percent of all French catch. Traditional fishing for domestic markets will remain possible, Le Maire said.

Source: http://www.reuters.com/article/idUSTRE6121Z620100203

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Slipped Through the Net: Failing Fish Stocks

ScienceDaily — At the Development Summit in Johannesburg in 2002, the European countries agreed to rebuild their fish stocks to levels that can produce the maximum sustainable yield, no later than 2015. According to scientists of the Excellence Cluster "Future Ocean," that goal is already out of reach: Of 54 analysed stocks, only saithe, western horse mackerel and Baltic sprat have a sufficiently large stock size and are fished at a sustainable rate. The state of 12 stocks, including North Sea cod, plaice and halibut, is so bad that they can not recover sufficiently until 2015, even if all fishing was halted. Other stocks could reach the target if fishing pressure was reduced substantially, but that has not happened so far.

These results were published by Dr. Rainer Froese, Leibniz Institute of Marine Sciences (IFM-GEOMAR) und Prof. Dr. Alexander Proelß, Walter-Schücking-Institute of International Law of the University of Kiel, in the journal Fish and Fisheries. The German scientists, both members of the interdisciplinary Excellence Cluster "Future Ocean," point out that the continuous overfishing of European stocks constitutes a breach of the precautionary principle, which is a binding principle of Community law.

"The precautionary principle is a binding legal principle for the organs of the European Commission and for the Council of Ministers. The current practice of continuous overfishing violates international law as well as Community law," says Prof. Dr. Alexander Proelß, expert of international law at the Walter-Schücking-Institute.

The obligation to manage fish stocks such that they can produce the maximum sustainable yield is part of the Law of the Sea (UNCLOS) of 1982, which entered into force in 1994. In the "Johannesburg Plan of Implementation" (2002), the European Union as well as Norway, Russia and Iceland, agreed to rebuild their fish stocks to the level that can produce the maximum sustainable yield, no later than 2015. "Until now, the provisions of the Law of the Sea have not been introduced into national law, and the plan of implementation had no visible impact on European fisheries management," says Proelß.

On the contrary: the fishing quotas for 2010 decreed by the Council of Ministers again exceed by far the catches that would allow the rebuilding of the stocks. "If this practice continues, Europe will miss by more than 30 years the goal that it has propagated," says Dr. Rainer Froese, fisheries biologist at the Kiel Leibniz Institute of Marine Sciences (IFM-GEOMAR).

Yet, catches from sustainably managed stocks could be substantially higher. "Our analysis suggests that landings could be 79% higher if stocks had been managed according to the international agreements," says Froese. "However, in European waters stocks are intentionally managed such that they stay close to the brink of collapse. This policy makes no sense from an ecological or economic point of view."

Source: http://www.sciencedaily.com/releases/2010/01/100121155224.htm

---

About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Coral Can Recover from Climate Change Damage, New Research Suggests

ScienceDaily — A study by the University of Exeter provides the first evidence that coral reefs can recover from the devastating effects of climate change. Published Jan. 11, 2010 in the journal PLoS ONE, the research shows for the first time that coral reefs located in marine reserves can recover from the impacts of global warming.

Scientists and environmentalists have warned that coral reefs may not be able to recover from the damage caused by climate change and that these unique environments could soon be lost forever. Now, this research adds weight to the argument that reducing levels of fishing is a viable way of protecting the world's most delicate aquatic ecosystems.

Increases in ocean surface water temperatures subject coral reefs to stresses that lead quickly to mass bleaching. The problem is intensified by ocean acidification, which is also caused by increased CO₂. This decreases the ability of corals to produce calcium carbonate (chalk), which is the material that reefs are made of.

Approximately 2% of the world's coral reefs are located within marine reserves, areas of the sea that are protected against potentially-damaging human activity, like dredging and fishing.
The researchers conducted surveys of ten sites inside and outside marine reserves of the Bahamas over 2.5 years. These reefs have been severely damaged by bleaching and then by hurricane Frances in the summer of 2004. At the beginning of the study, the reefs had an average of 7% coral cover. By the end of the project, coral cover in marine protected areas had increased by an average of 19%, while reefs in non-reserve sites showed no recovery.
Professor Peter Mumby of the University of Exeter said: "Coral reefs are the largest living structures on Earth and are home to the highest biodiversity on the planet. As a result of climate change, the environment that has enabled coral reefs to thrive for hundreds of thousands of years is changing too quickly for reefs to adapt.

"In order to protect reefs in the long-term we need radical action to reduce CO₂ emissions. However, our research shows that local action to reduce the effects of fishing can contribute meaningfully to the fate of reefs. The reserve allowed the number of parrotfishes to increase and because parrotfish eat seaweeds, the corals could grow freely without being swamped by weeds. As a result, reefs inside the park were showing recovery whereas those with more seaweed were not. This sort of evidence may help persuade governments to reduce the fishing of key herbivores like parrotfishes and help reefs cope with the inevitable threats posed by climate change."

Professor Mumby's research was funded by National Environment Research Council (NERC) and the Khaled bin Sultan Living Oceans Foundation.

Reef facts

• A coral reef is made up of thin layers of calcium carbonate (limestone) secreted over thousands of years by billions of tiny soft bodied animals called coral polyps.
• Coral reefs are the world's most diverse marine ecosystems and are home to twenty-five percent of known marine species, including 4,000 species of fish, 700 species of coral and thousands of other plants and animals.
• Coral reefs have been on the planet for over 400 million years.
• The largest coral reef is the Great Barrier Reef, which stretches along the northeast coast of Australia, from the northern tip of Queensland, to just north of Bundaberg. At 2,300km long, it is the largest natural feature on Earth.
• Coral reefs occupy less than one quarter of one percent of the Earth's marine environment, yet they are home to more than a quarter of all known fish species.
• As well as supporting huge tourist industries, coral reefs protect shorelines from erosion and storm damage.

High quality reef videos by Professor Peter Mumby can be viewed at: www.reefvid.org
The main funding for the research came from Khaled bin Sultan Living Oceans Foundation and the Natural Environment Research Council.

Source: http://www.sciencedaily.com/releases/2010/01/100109002310.htm

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About Oceanic Defense
We are an international non-profit organization with members in over 60 countries, spanning 6 continents with 1 mission; healthy aquatic ecosystems free from human abuse and neglect. Oceanic Defense teaches people to protect our oceans by acting responsibly as consumers and by making smart decisions in our daily lives. Whether we are buying groceries, commuting to work, planning a vacation or advocating within our own communities; each action we take or decision we make either helps or hurts our oceans. We empower people to be part of the solution rather than part of the problem and work together to protect our blue planet.

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Giant tuna fetches $177,000 at Japan fish auction

By SHINO YUASA, Associated Press Writer Shino Yuasa, Associated Press Writer

TOKYO – A giant bluefin tuna fetched 16.3 million yen ($177,000) in an auction Tuesday at the world's largest wholesale fish market in Japan.

The 513-pound (233-kilogram) fish was the priciest since 2001 when a 440-pound (200 kilogram) tuna sold for a record 20.2 million yen ($220,000) at Tokyo's Tsukiji market.

The gargantuan tuna was bought and shared by the owners of two Japanese sushi restaurants and one Hong Kong-based sushi establishment, said a market representative on condition of anonymity because he was not authorized to disclose the information.

Caught off the coast of northern Japan, the big tuna was among 570 put up for auction Tuesday. About 40 percent of the auctioned fish came from abroad, including from Indonesia and Mexico, the representative said.

Japan is the world's biggest consumer of seafood with Japanese eating 80 percent of the Atlantic and Pacific bluefins caught. The two tuna species are the most sought after by sushi lovers.

However, tuna consumption in Japan has declined because of a prolonged economic slump as the world's second-largest economy struggles to shake off its worst recession since World War II.

"Consumers are shying away from eating tuna ... We are very worried about the trend," the market representative said.

Apart from falling demand for tuna, wholesalers are worried about growing calls for tighter fishing rules amid declining tuna stocks.

The International Commission for the Conservation of Atlantic Tunas in November slashed the quota for the 2010 catch by about one-third to 13,500 tons (12,250 metric tons) — a move criticized by environmentalists as not going far enough.

Source: http://news.yahoo.com/s/ap/20100105/ap_on_bi_ge/as_japan_giant_tuna_sold

Skate may be fished to extinction

A species of skate could become the first marine fish driven to extinction by commercial fishing, say scientists.

A study reveals that an error in the classification of the species has meant researchers have failed to see just how close to the brink it is.

The French team reports its findings in the journal Aquatic Conservation.

Marine biologist Nicholas Dulvy from Simon Fraser University in Canada says the skate is now "the most precarious marine species on Earth".

The team's genetic studies have revealed that what is referred to as the common skate is actually two clearly distinct species - the flapper skate (Dipturus intermedia) and the blue skate (Dipturus flossada).

The fish were originally categorised separately, but an influential study in 1926 recognised only one valid species - Dipturus batis. This classification has been unchallenged since.

The 80-year error has ensured that fisheries have not been catching what they thought, explained Dr Dulvy, who is also co-chair of the International Union for the Conservation of Nature's (IUCN's) shark specialist group.

The result has been that catches of the smaller, more resilient blue skate has entirely masked the decline of the flapper skate.

Disappearing fast

The research team, led by Samuel Iglesias from the Marine Biology Station in Concarneau on the west coast of France, paints a very bleak picture for the future of the flapper skate.

Dr Iglesias and his team spent over a year working with French fisheries and taking DNA samples from the skate that was caught.

His findings finally revealed that the larger D. intermedia species was indeed in serious decline.

Dr Iglesias said: "The threat of extinction for European Dipturus together with mislabelling in fishery statistics highlight the need for a huge reassessment of population for the different Dipturus species in European waters.

"Without revision and recognition of its distinct status the world's largest skate, D. intermedia, could soon be rendered extinct."

Dr Dulvy added: "As far as we can tell, [humans have] not yet driven anything fully to extinction by over-fishing."

He and many other marine scientists are now very concerned that this skate species will be the first.

By Victoria Gill
Science reporter, BBC News

Source: http://news.bbc.co.uk/2/hi/science/nature/8367045.stm

Coral Reef Decline - Not Just Overfishing

ScienceDaily — Coral reefs, the rainforests of the sea, feed a large portion of the world's population, protect tropical shorelines from erosion, and harbor animals and plants with great potential to provide new therapeutic drugs. Unfortunately, reefs are now beset by problems ranging from local pollution and overfishing to outbreaks of coral disease and global warming. Although most scientists agree that reefs are in desperate trouble, they disagree strongly over the timing and causes of the coral reef crisis. This is not just an academic exercise, because different answers dictate different strategies for managers and policymakers intent on saving reef ecosystems. The cover story published this month in Geology helps focus the debate.

A team led by Richard Aronson of the Dauphin Island Sea Lab in Alabama took cores through reef frameworks in Belize to reconstruct the history of the reefs over the past several thousand years. Although some scientists have suggested that reefs began their decline centuries ago due to early overfishing, Aronson's team found that coral populations were healthy and vibrant until the 1980s, when they were killed by disease and high sea temperatures. The research effort was supported by the National Geographic Society, the Smithsonian Institution and the National Science Foundation.

As Aronson points out, "Protecting fish populations is important in its own right, but it won't save the corals. Corals are being killed at an unprecedented rate by forces outside local control. Saving coral reefs means addressing global environmental issues--climate change in particular--at the highest levels of government."

Source: http://www.sciencedaily.com/releases/2005/08/050830072609.htm

Fisheries, Not Whales, To Blame For Shortage Of Fish

ScienceDaily — The argument that increasing whale populations are behind declining fish stocks is completely without scientific foundation, leading researchers and conservation organizations said in June as the International Whaling Commission opened its 60th meeting in Santiago, Chile.

The Humane Society International, WWF and the Lenfest Ocean Program today presented three new reports debunking the science behind the ‘whales-eat-fish’ claims emanating from whaling nations Japan, Norway and Iceland. The argument has been used to bolster support for whaling, particularly from developing nations.

“It is not the whales, it is over-fishing and excess fishing capacity that are responsible for diminishing supplies of fish in developing countries,” said fisheries biologist Dr. Daniel Pauly, director of the University of British Columbia Fisheries Centre.

“Making whales into scapegoats serves only to benefit wealthy whaling nations while harming developing nations by distracting any debate on the real causes of the declines of their fisheries.”

Who’s eating all the fish? The food security rationale for culling cetaceans, the report co-authored by Dr Pauly for the Humane Society International contrasts “the widely different impacts of fisheries and marine mammals” with fisheries targeting larger fish where available and marine mammals consuming mainly smaller fish and organisms.

“The decline of the mean trophic levels of fisheries catch over the past 50 years is a signature of fishing down marine food webs and leaves marine mammals exonerated,” the report said.

The report also probes the culling whales increases food security for the poor argument by examining the final destination of catches of coastal fisheries in the South Pacific, Caribbean and West Africa. With less than half the catch going to domestic markets and the majority “gravitating toward the markets of affluent developed countries, one can speak of fish migrating from the more needy to the less needy”.

Also presented to the IWC Scientific Committee was the preliminary results into analysis of the interaction between whales and commercial fisheries in north west Africa. The modeling, funded by the Lenfest Ocean Program, shows no real competition between local or foreign fisheries and great whales.

The whales spend only a few months in the area during their vast seasonal migrations, eat relatively little while breeding and tend to consume fundamentally different types of food resources than the marine species targeted by both local and foreign fisheries. Inserting modelling assumptions to presume that whales are not breeding in the area and eat species important to the fishing industry still fails to show whales are a significant source of competition to fishing.

Also released today is review of the scientific literature originating from Japan and Norway - the two countries most strongly promoting the idea that whales pose problems for fisheries. The review, funded by WWF, found significant flaws in much of the science and concluded that “where good data are available, there is no evidence to support the contention that marine mammal predation presents an ecological issue for fisheries.”

Dr. Susan Lieberman of WWF said “These three reports provide yet more conclusive evidence that whales are not responsible for the degraded state of the world’s fisheries. It is now time for governments to focus on the real reason for fisheries decline – unsustainable fishing operations.”

Source: http://www.sciencedaily.com/releases/2008/06/080629144231.htm

Modest Fisheries Reduction Could Protect Vast Coastal Ecosystems

ScienceDaily - A reduction of as little as five per cent in fisheries catch could result in as much as 30 per cent of the British Columbia coastal ecosystems being protected from overfishing, according to a new study from the UBC Fisheries Centre in Canada.

The study, by Natalie Ban and Amanda Vincent of Project Seahorse, proposes modest reductions in areas where fisheries take place, rather than the current system of marine protected areas which only safeguard several commercially significant species, such as rockfish, shrimp, crab, or sea cucumber. The article is published July 21 in PLoS One.

Using B.C.'s coastal waters as a test case, the study affirms that small cuts in fishing – if they happen in the right places – could result in very large unfished areas. For example, a two per cent cut could result in unfished areas covering 20 per cent of the B.C. coast, offered real conservation gains.

"The threat of over-fishing to our marine ecosystems is well-documented," says Ban, who recently completed her PhD at the UBC Fisheries Centre. "Our study suggests a different approach could reduce the impacts on fishers as well as helping us move towards achieving conservation goals."

Part of the reason for the research was to open a debate on how to meet conservation goals set during the 2002 World Summit on Sustainable Development, which included establishing a network of marine protected areas by 2012.

"With the current rates of progress, there is no chance of meeting our 2012 targets," says Ban. "Given that fishers recognize the problem of overfishing but often regard marine protected areas as serving only to constrain them, another approach must be found. That's why we undertook this study."

The research looked at spatial catch data from Fisheries and Ocean Canada for 13 commercial fisheries on Canada's west coast to show that large areas representing diverse ecoregions and habitats might be protected at a small cost to fisheries.

"Given the dismal state of many fisheries, we urgently need to identify alternative approaches to sustaining marine life while respecting the needs of fishers and fishing communities," says Amanda Vincent, Canada Research Chair in Marine Conservation at UBC and Project Seahorse director. "We have little to lose – and much to gain – in trying a new approach in areas where marine conservation remains inadequate. Our research is globally relevant."

'Sobering' Decline Of Caribbean's Big Fish, Fisheries: Overfishing Deemed Most Likely Cause

ScienceDaily — Sharks, barracuda and other large predatory fishes disappear on Caribbean coral reefs as human populations rise, endangering the region's marine food web and ultimately its reefs and fisheries, according to a sweeping study by researcher Chris Stallings of The Florida State University Coastal and Marine Laboratory.

While other scientists working in the Caribbean have observed the declines of large predators for decades, the comprehensive work by Stallings documents the ominous patterns in far more detail at a much greater geographic scale than any other research to date.

"Seeing evidence of this ecological and economic travesty played out across the entire Caribbean is truly sobering," said Associate Professor John Bruno of the University of North Carolina at Chapel Hill, who served as the PLoS One academic editor for Stallings' new paper.

"I examined 20 species of predators, including sharks, groupers, snappers, jacks, trumpetfish and barracuda, from 22 Caribbean nations," said Stallings, a postdoctoral associate at the FSU Coastal and Marine Laboratory. "I found that nations with more people have reefs with far fewer large fish because as the number of people increases, so does demand for seafood. Fishermen typically go after the biggest fish first, but shift to smaller species once the bigger ones become depleted. In some areas with large human populations, my study revealed that only a few small predatory fish remain."

Stallings said that although several factors -- including loss of coral reef habitats -- contributed to the general patterns, careful examination of the data suggests overfishing as the most likely reason for the disappearance of large predatory fishes across the region. He pointed to the Nassau grouper as a prime example. Once abundant throughout the Caribbean, Nassau grouper have virtually disappeared from many Caribbean nearshore areas and are endangered throughout their range.

"Large predatory fish such as groupers and sharks are vitally important in marine food webs," Stallings said. "However, predicting the consequence of their loss is difficult because of the complexity of predator-prey interactions. You can't replace a 10-foot shark with a one-foot grouper and expect there to be no effect on reef communities. Shifts in abundance to smaller predators could therefore have surprising and unanticipated effects. One such effect may be the ability of non-native species to invade Caribbean reefs."

A case in point, said Stallings, is the ongoing invasion by Pacific lionfish, which were introduced by aquarium releases.

"Lionfish are minor players on their native Pacific reefs, yet they are undergoing a population explosion and overeating small fishes in the greater Caribbean region," said Professor Mark Hixon of Oregon State University, Stallings' doctoral advisor at OSU. "Preliminary evidence suggests that lionfish are less invasive where large predatory native fishes are abundant, such as in marine reserves," Hixon said.

The study also demonstrates the power of volunteer and community research efforts by non-scientists. Stallings used data from the Reef Environmental Education Foundation's (REEF) online database, which contains fish sightings documented by trained volunteer SCUBA divers, including more than 38,000 surveys spanning a 15-year period.

"Chris was completely undaunted by the lack of fisheries data and essentially adopted the 'Audubon Christmas Bird Count' approach in a marine system to find strong evidence for a native fisheries effect," said Felicia Coleman, director of the FSU Coastal and Marine Laboratory and Stallings' postdoctoral advisor.

Given that about half the world's populations live near coastlines and that the world population is growing, demands for ocean-derived protein will continue to increase, Stallings warned. He said meeting such demands while retaining healthy coral reefs may require multiple strategies, including implementation of marine reserves, finding alternative sources of protein, and increased efforts to implement family-planning strategies in densely populated areas.

Journal reference:

1. Stallings et al. Fishery-Independent Data Reveal Negative Effect of Human Population Density on Caribbean Predatory Fish Communities. PLoS ONE, 2009; 4 (5): e5333 DOI: 10.1371/journal.pone.0005333

Adapted from materials provided by Florida State University, via EurekAlert!, a service of AAAS.

Dolphin Population Stunted By Fishing Activities, Study Finds

ScienceDaily — Despite broad "dolphin safe" practices, fishing activities have continued to restrict the growth of at least one Pacific Ocean dolphin population, a new report led by a researcher at Scripps Institution of Oceanography at UC San Diego has concluded.

Populations of dolphins in the Eastern Pacific were expected to increase in abundance after successful regulations and agreements were enacted to reduce dolphin deaths as a result of fishing "bycatch," cases in which animals are caught unintentionally along with intended targets.

But the new study, published in the October issue of Marine Ecology Progress Series, reveals that negative impacts from fishing activities remain. Instead of reducing numbers through direct mortalities, the study by Katie Cramer of Scripps Institution of Oceanography and Wayne Perryman and Tim Gerrodette of the National Oceanic and Atmospheric Administration's (NOAA's) Southwest Fisheries Science Center shows that fishing activities have disrupted the reproductive output of the northeastern pantropical spotted dolphin. The researchers note that reproductive output of the eastern spinner dolphin also declined, but a direct link to fishing effort was inconclusive.

"The results of this study clearly show that depleted dolphin populations have failed to recover in part due to a decline in reproductive output, and that fishing has had an effect on reproduction," said Cramer, a graduate student researcher in the Scripps Center for Marine Biodiversity and Conservation. "This shows that the fisheries indeed are still having an impact."

The new conclusions are based on broad surveys conducted by NOAA Fisheries Service between 1987 and 2003 designed to assess the size and health of dolphin populations in the eastern Pacific Ocean. The surveys included military reconnaissance camera images of more than 20,000 animals.

Cramer, who participated in helicopter surveys between 1998 and 2003, and her colleagues used the image database to analyze entire dolphin schools, focusing in particular on mother-calf pairs.

The scientists compared the data with the number of fishing events in which a dolphin school is chased by speedboats and encircled in a large "purse-seine" net in order to capture the large yellowfin tuna that often swim with dolphin schools. While such fishing led to high dolphin mortalities after purse-seine fishing was launched in the eastern tropical Pacific in the 1950s, bycatch deaths declined by the end of the 1990s due to new fishing techniques that ensured that dolphins are eventually released from the nets alive.

Yet despite mortality reductions, dolphin populations have not recovered at a rate expected since bycatch was reduced.

Using the aerial photographic database, Cramer and her colleagues found a strong link between the amount of fishing and reproductive output in a given year for the dolphin population most heavily targeted by the fishery, the northeastern pantropical spotted dolphin. Both the proportion of adult animals in the photographs with a calf, and the length at which calves disassociated from their mothers (a measure of the length at which the calves stop nursing), declined with increasing fishing effort.

Together, the results showed that fishing had a negative impact on calf survival rates and/or birth rates. This could be caused when fishing operations separate mothers from their suckling calves, interfere with the conception or gestation of calves or a combination of the two.

"The link between fishing activity and ... reproductive output indicates that the fishery has population-level effects beyond reported direct kill," the authors write in their report.

What remains unknown is the exact mechanism leading to reduced reproductive output. This question is currently being investigated by researchers at NOAA Fisheries' Southwest Fisheries Science Center in La Jolla.

Adapted from materials provided by University of California - San Diego.

Corals Stay Close to Home

ScienceDaily — The thought of coral reefs tends to conjure up images of tropical vacations, complete with snorkeling among tropical fish in crystal clear waters

Rapid climate change, and increased pollution, ocean acidification and overfishing threaten to darken this picture considerably. These factors heavily stress corals, and thus put both the countless marine organisms that count on corals for habitat and shelter, and the $1 billion dollar tourism industry fueled by coral reefs at significant risk.

Conservation biologists have been scrambling to find ways to conserve and protect these remarkable sea creatures. However, the design of marine reserves requires knowledge of the distances moved by the mobile juvenile stage of corals so that the natural processes that maintain healthy populations can be encouraged.

A recent study published in Evolutionary Applications by Australian biologist Jim Underwood has found surprisingly that despite the fact that corals cast their eggs and sperm haphazardly into the oceans, certain species of coral show remarkable fidelity to their home range.

Underwood sampled DNA from coral reefs in the Indiana Ocean and found that individual corals located in the same group of reefs are more closely related than previously thought.

These results suggest that since most recruitment of these Indian Ocean coral populations comes from other locally sourced coral, one cannot depend on genetic material from distant populations of corals to replenish or restore degraded local populations. In these regions, marine reserves that maintain high local genetic diversity should be favoured.

Journal reference:

1. Underwood et al. Genetic diversity and divergence among coastal and offshore reefs in a hard coral depend on geographic discontinuity and oceanic currents. Evolutionary Applications, 2009; 2 (2): 222 DOI: 10.1111/j.1752-4571.2008.00065.x

Adapted from materials provided by Wiley - Blackwell, via AlphaGalileo.

Shellfish Face An Uncertain Future In High Carbon Dioxide World

ScienceDaily — Overfishing and disease have decimated shellfish populations in many of the world's temperate estuarine and coastal ecosystems. Smithsonian scientists, led by Whitman Miller, ecologist at the Smithsonian Environmental Research Center in Edgewater, Md., have discovered another serious threat to these valuable filter feeders—rising levels of atmospheric carbon dioxide that contribute to the acidification of open ocean, coastal and estuarine waters.

Their findings are being published in PLoS One.

For shellfish and other organisms that have calcium carbonate shells and structures, the problem begins when atmospheric CO2 dissolves in seawater and creates carbonic acid that is then rapidly transformed into carbonate and bicarbonate ions in the water. Increased acidity tips the balance toward bicarbonate formation and away from carbonate. Less carbonate in the water means that shellfish have fewer building blocks to generate their shells. If the water is acidic enough, shells can even begin to dissolve.

"Estuarine and coastal ecosystems may be especially vulnerable to changes in water chemistry caused by elevated CO2 because their relative shallowness, reduced salinity and lower alkalinity makes them inherently less buffered to changes in pH than in the open ocean," said Miller. For many calcifying organisms, CO2-induced acidification poses a serious challenge because these organisms may experience reduced rates of growth and calcification that "when combined with other environmental stresses, could spell disaster."

Larval oysters are thought to be particularly susceptible to acidification since larvae produce shells made of aragonite, a crystalline form of calcium carbonate that is prone to erosion at low pH. Adult oysters continue to build shell but generate calcite, a more durable form of calcium carbonate. In Miller's study, the larvae of Eastern oysters (Crassostrea virginica) and Suminoe oysters (Crassostrea ariakensis) were cultured in estuarine water that was held at four separate CO2 concentrations, reflecting atmospheric conditions from the pre-industrial era, the present, and those predicted in the coming 50 and 100 years. To test the effects of acidification, Miller monitored their growth and measured the amounts of calcium carbonate deposited in larval shells over the course of one month.

Miller and his team found that Eastern oysters experienced a 16 percent decrease in shell area and a 42 percent reduction in calcium content when specimens in the pre-industrial CO2 treatment were compared with those exposed to the levels predicted for the year 2100. Surprisingly, the closely related Suminoe oysters from Asia showed no change to either growth or calcification.

The results reported suggest that the impacts of acidification may be tied to a species' unique evolutionary history and environmental setting, implying that predictions may be more complex than previously thought. "In the Chesapeake Bay, oysters are barely holding on, where disease and overfishing have nearly wiped them out. Whether acidification will push Eastern oysters, and the many species that depend on them, beyond a critical tipping point remains to be seen" said Miller.

With numbers so critically low—the oyster population in the Chesapeake Bay today stands at just 2 percent of what it was in colonial times—future losses could have dire consequences, both environmentally and economically. Indeed, the recently enacted Federal Ocean Acidification Research and Monitoring Act of 2009 recognizes the urgent need to begin addressing impacts of acidification on estuaries and their biota.

With the continued burning of fossil fuels, further acidification is unavoidable. Miller's team is keenly interested in what the biological and ecological responses will be in order to better inform current and future environmental restoration efforts. "In a high CO2 world, calcifying organisms may well begin to lose out to competition with non-calcifiers, a situation that could fundamentally change benthic communities. Understanding how such changes may play out in estuaries and coastal waters, which teem with calcifying biota, and which are also the centers of many commercial fisheries and human activities, seems especially urgent" said Miller.

Funding for this research was provided by the Seward Johnson Endowment provided through the Smithsonian Marine Science Network as well as federal appropriations made to the Smithsonian Institution.

Journal reference:

1. Miller et al. Shellfish Face Uncertain Future in High CO2 World: Influence of Acidification on Oyster Larvae Calcification and Growth in Estuaries. PLoS ONE, 2009; 4 (5): e5661 DOI: 10.1371/journal.pone.0005661

Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.

'Jellyfish Joyride' A Threat To The Oceans

ScienceDaily — Early action could be crucial to addressing the problem of major increases in jellyfish numbers, which appears to be the result of human activities.

New research led by CSIRO Climate Adaptation Flagship and University of Queensland scientist, Dr Anthony Richardson, presents convincing evidence that this ’jellyfish joyride’ is associated with over-fishing and excess nutrients from fertilisers and sewage.

“Dense jellyfish aggregations can be a natural feature of healthy ocean ecosystems, but a clear picture is now emerging of more severe and frequent jellyfish outbreaks worldwide,” Dr Richardson says.

“In recent years, jellyfish blooms have been recorded in the Mediterranean, the Gulf of Mexico, the Black and Caspian Seas, the Northeast US coast, and particularly in Far East coastal waters.

“The most dramatic have been the outbreaks in the Sea of Japan involving the gargantuan Nomura jellyfish which can grow up to 2 m in diameter and weigh 200 kg.”

The new research, by Dr Richardson and colleagues at the University of Miami, Swansea University and the University of the Western Cape, has been published in the international journal; Trends in Ecology and Evolution, in time for World Oceans Day on 8 June.

“Fish normally keep jellyfish in check through competition and predation but overfishing can destroy that balance,” Dr Richardson says. “For example, off Namibia intense fishing has decimated sardine stocks and jellyfish have replaced them as the dominant species.”

Climate change may favour some jellyfish species by increasing the availability of flagellates in surface waters – a key jellyfish food source. Warmer oceans could also extend the distribution of many jellyfish species.

“Mounting evidence suggests that open-ocean ecosystems can flip from being dominated by fish, to being dominated by jellyfish,” Dr Richardson says “This would have lasting ecological, economic and social consequences.

“We need to start managing the marine environment in a holistic and precautionary way to prevent more examples of what could be termed a ‘jellyfish joyride’.”

Journal reference:

1. Richardson et al. The jellyfish joyride: causes, consequences and management responses to a more gelatinous future. Trends in Ecology & Evolution, 2009; 24 (6): 312 DOI: 10.1016/j.tree.2009.01.010

Adapted from materials provided by CSIRO Australia.

Where are the fish? Ocean fisheries in trouble

Scientists, politicians, and fisherman alike know there's a problem. Smaller fish and smaller catches suggest that the world's oceans are no longer producing at their full potential. The bounty of the sea is becoming less generous -- scientists estimate that the number of large fish in the oceans has fallen by as much as 90% since the 1950s. Improvements in technology have made it easier for fisherman to find and harvest more fish than ever before while demand for sea life products -- which are consumed by both the rich and poor -- is at an all time high.

While global marine catches have yet to fall far from peak levels, a recent report (Review of the state of world marine fishery resources) from the The United Nations Food and Agriculture Organization's Fisheries Department says 77 percent of the world's fish stocks are "fully exploited" -- producing catches that are already at or very close to their maximum sustainable production limit, over-exploited, depleted, or recovering. The proportion of stocks FAO classifies as "under-exploited" has fallen to 3 percent, while the amount of "modertately exploited" stocks stands at 20 percent.

Several of the world's important fisheries -- including the cod and haddock fishery of the Grand Banks off Newfoundland in the north Atlantic -- have collapsed and increasingly, fisherman are turning to smaller, less attractive, and less accessible species to make up for the shortfall of premium species. Trawlers are now fishing waters more than a mile deep to catch species such as the Orange roughy that few would have considered edible or useful a decade ago. These species are also at risk of overexploitation. In the case of the orange roughy, the southeast fishery of Australia saw its orange roughy catches fall from over 50,000 tonnes in 1990 to 5,579 tonnes in 1997.

Worse, the amount of waste in commercial fishing is staggering. More than 80 percent of catch in some fisheries may be by-catch, or species other than the species for which the fishing gear was set. Bycatch, also called incidental catch, is typically discarded at sea and may include fish, corals, sea turtles, and dolphins.


Fishermen race for fish
The fundamental problem with facing the management of the world's fisheries is the "tragedy of the commons." Since in many areas, ocean fish are essentially an open access resource there is no incentive for an individual fisherman to restrain his catch. If an individual fisherman conserves for tomorrow, he is only providing someone else with the resource today.

Looking for a solution
Assigning property rights may help the situation and in some areas such schemes have showed signs of success. On the open ocean however, it is considerably more difficult to enforce boundaries and set binding fishing limits. Plus, there is no guarantee that local fisheries will not be overexploited by commercial interests. As some wealth countries have depleted their own fisheries, they have moved into poor countries, buying fishing rights -- often from corrupt bureaucrats -- and then continuing their unsustaiable plunder of marine resources.

Some have argued that a global network of marine parks could help protect and restore some of the world's most impacted fisheries, while aquaculture -- which has expereinced tremendous growth in recent years -- could supplement protein needs. But in order for any sort of conservation plan to be successful, all the involved parties must be brought to the table to hammer out a mutually agreeable plan. If past summits are any indication, this could take a very long time.

You can learn more on the state of the world's fisheries at http://www.fao.org/fi/default.asp

orginal story from: http://news.mongabay.com/2005/0504-rhett_butler.html

Studies Shed Light On Collapse Of Coral Reefs; Biologists 'Starting To Think More Outside The Box'

A coral colony

Underwatertimes.com News Service

CORVALLIS, Oregon -- An explosion of knowledge has been made in the last few years about the basic biology of corals, researchers say in a new report, helping to explain why coral reefs around the world are collapsing and what it will take for them to survive a gauntlet of climate change and ocean acidification.

Corals, it appears, have a genetic complexity that rivals that of humans, have sophisticated systems of biological communication that are being stressed by global change, and are only able to survive based on proper function of an intricate symbiotic relationship with algae that live within their bodies.

After being a highly successful life form for 250 million years, disruptions in these biological and communication systems are the underlying cause of the coral bleaching and collapse of coral reef ecosystems around the world, scientists will report tomorrow in the journal Science.

The research was funded in part by the National Science Foundation.

"We've known for some time the general functioning of corals and the problems they are facing from climate change," said Virginia Weis, a professor of zoology at Oregon State University. "But until just recently, much less has been known about their fundamental biology, genome structure and internal communication. Only when we really understand how their physiology works will we know if they can adapt to climate changes, or ways that we might help."

Corals are tiny animals, polyps that exist as genetically identical individuals, and can eat, defend themselves and kill plankton for food. In the process they also secrete calcium carbonate that becomes the basis for an external skeleton on which they sit. These calcified deposits can grow to enormous sizes over long periods of time and form coral reefs – one of the world's most productive ecosystems, which can harbor more than 4,000 species of fish and many other marine life forms.

But corals are not really self sufficient. Within their bodies they harbor highly productive algae – a form of marine plant life – that can "fix" carbon, use the energy of the sun to conduct photosynthesis and produce sugars.

"Some of these algae that live within corals are amazingly productive, and in some cases give 95 percent of the sugars they produce to the coral to use for energy," Weis said. "In return the algae gain nitrogen, a limiting nutrient in the ocean, by feeding off the waste from the coral. It's a finely developed symbiotic relationship."

What scientists are learning, however, is that this relationship is also based on a delicate communication process from the algae to the coral, telling it that the algae belong there, and that everything is fine. Otherwise the corals would treat the algae as a parasite or invader and attempt to kill it.

A coral skeleton

"Even though the coral depends on the algae for much of its food, it may be largely unaware of its presence," Weis said. "We now believe that this is what's happening when the water warms or something else stresses the coral – the communication from the algae to the coral breaks down, the all-is-well message doesn't get through, the algae essentially comes out of hiding and faces an immune response from the coral."

This internal communication process, Weis said, is not unlike some of the biological processes found in humans and other animals. One of the revelations in recent research, she said, is the enormous complexity of coral biology, and even its similarity to other life forms. A gene that controls skeletal development in humans, for instance, is the identical gene in corals that helps it develop its external skeleton – conserved in the different species over hundreds of millions of years since they parted from a common ancestor on their separate evolutionary paths.

There's still much to learn about this process, researchers said, and tremendous variation in it. For one thing, there are 1,000 species of coral and perhaps thousands of species of algae all mixing and matching in this symbiotic dance. And that variation, experts say, provides at least some hope that combinations will be found which can better adapt to changing conditions of ocean temperature, acidity or other threats.

The problems facing coral reefs are still huge, and increasing. They are being pressured by changes in ocean temperature, pollution, overfishing, sedimentation, acidification, oxidative stress and disease, and the synergistic effect of some of these problems may destroy reefs even when one cause by itself would not. Some estimates have suggested 20 percent of the world's coral reefs are already dead and an additional 24 percent are gravely threatened.

The predicted acidification of the oceans in the next century is expected to decrease coral calcification rates by 50 percent and promote the dissolving of coral skeletons, the researchers noted in their report.

"With some of the new findings about coral symbiosis and calcification, and how it works, coral biologists are now starting to think more outside the box," Weis said. "Maybe there's something we could do to help identify and protect coral species that can survive in different conditions. Perhaps we won't have to just stand by as the coral reefs of the world die and disappear."