Privacy Policy for http://visitfisheries.blogspot.com/
If you require any more information or have any questions about our privacy policy, please feel free to contact us by email at uyundatul@gmail.com.
At http://visitfisheries.blogspot.com/, the privacy of our visitors is of extreme importance to us. This privacy policy document outlines the types of personal information is received and collected by http://visitfisheries.blogspot.com/ and how it is used.
Log Files
Like many other Web sites, http://visitfisheries.blogspot.com/ makes use of log files. The information inside the log files includes internet protocol ( IP ) addresses, type of browser, Internet Service Provider ( ISP ), date/time stamp, referring/exit pages, and number of clicks to analyze trends, administer the site, track user’s movement around the site, and gather demographic information. IP addresses, and other such information are not linked to any information that is personally identifiable.
Cookies and Web Beacons
http://visitfisheries.blogspot.com/ does use cookies to store information about visitors preferences, record user-specific information on which pages the user access or visit, customize Web page content based on visitors browser type or other information that the visitor sends via their browser.
DoubleClick DART Cookie
.:: Google, as a third party vendor, uses cookies to serve ads on http://visitfisheries.blogspot.com/.
.:: Google's use of the DART cookie enables it to serve ads to users based on their visit to http://visitfisheries.blogspot.com/ and other sites on the Internet.
.:: Users may opt out of the use of the DART cookie by visiting the Google ad and content network privacy policy at the following URL - http://www.google.com/privacy_ads.html
Some of our advertising partners may use cookies and web beacons on our site. Our advertising partners include ....
Google Adsense
These third-party ad servers or ad networks use technology to the advertisements and links that appear on http://visitfisheries.blogspot.com/ send directly to your browsers. They automatically receive your IP address when this occurs. Other technologies ( such as cookies, JavaScript, or Web Beacons ) may also be used by the third-party ad networks to measure the effectiveness of their advertisements and / or to personalize the advertising content that you see.
http://visitfisheries.blogspot.com/ has no access to or control over these cookies that are used by third-party advertisers.
You should consult the respective privacy policies of these third-party ad servers for more detailed information on their practices as well as for instructions about how to opt-out of certain practices. http://visitfisheries.blogspot.com/'s privacy policy does not apply to, and we cannot control the activities of, such other advertisers or web sites.
If you wish to disable cookies, you may do so through your individual browser options. More detailed information about cookie management with specific web browsers can be found at the browsers' respective websites.
Monday, January 3, 2011
Saturday, January 1, 2011
Bluefin Tuna get a raw deal
I remember as a child, looking with awe at the old photographs of Hemmingway standing on the docks of Cat Cay, Bimini, next to those great fish he had wrestled from the sea, and I wonder how much those pictures influenced my notion of the sea. Maybe I believed him when he evoked Milton’s description of “A dark Illimitable ocean without bound,Without dimension....” It was in those early days that I traveled with my father while he was a surveyor for the US Coast and Geologic Survey, from the cold rocky coasts of Maine, the splashing surf of Montauk, the brimming bay at Kiptopeke, the entire coast of Florida and the gulf haunts from Mobile to Galveston. In all of these places, there was a mystery and belief in the limitless bounty and life of the sea. But I was wrong.
The great Bluefin Tuna is in danger of collapse and on the brink of extinction, and as reported by the Virginia Pilot, a U.S. proposal to temporarily ban bluefin fishing in the Eastern fishery to allow the species to recover was overwhelmingly rejected the International Commission for the Conservation of Atlantic Tunas (ICCAT) Ironically, this same commission also reports that nearly forty years of overfishing have depleted the stock of these giants to just 3% of its 1960 totals - a decline of 97%. Atlantic White Marlins are down to 6%, and Atlantic Blue Marlins have been driven to 20% of previous abundance. Intensified research has led to a better understanding of the Bluefin, but recent assessments show the population is at its lowest recorded levels, at the same time that fishing pressure is at its highest. Dockside reports from Atlantic fishers confirm what the scientific reports show – the Western Atlantic Bluefin populations continue to decline.
The great Bluefin Tuna are magnificent fish; they average ten feet in length and can weigh over 1,500 pounds. Atlantic Bluefin are warm-blooded ("homeothermic ") and are therefore able to regulate their body temperatures, which allows them to thrive in colder waters. Exceptional swimmers, they have been known to achieve speeds up to 20 knots and have been timed crossing the Atlantic Ocean in thirty days or less. They also have the ability to dive up to 3,000 feet in a matter of minutes. Unlike most tunas, Bluefin grow slowly and mature late, making them more vulnerable to intensive fishing. Demand is high since it is especially popular in sushi and sashimi dishes. In Japan, they can command prices of up to $100,000, (it is curious that ICCAT rejected the U.S. proposal, and instead adopted a Japanese proposal that requested that nations that fish the Eastern bluefin fishery submit a report to the commission that details how they are complying with the 2006 fishing plan that's in place.).
Note: Canned tuna purchased in the super market is most likely Yellowfin, Skipjack, Albacore or Bigeye (mostly the non-schooling fish).
According to Carl Safina of Blue Ocean Institute, the major cause for the decline of Bluefins is the unrestrained use of non-selective fishing gear, mainly pelagic longlines and seine or drift gillnets. Pelagic longlines can be over 25 miles in length and set with thousands of hooks. These nets and lines accidentally capture unmarketable juveniles; the majority of these fish are already dead when they reach the vessel. In many cases, the bycatch and bykill is larger than the actual number of marketable target fish caught.
But there are efforts to save the Bluefin. Earthjustice, on behalf of Blue Ocean Institute and Carl Safina, filed a lawsuit challenging the failure of the National Marine Fisheries Service (NMFS) to limit longline fishing in the Gulf of Mexico. Dr. Safina is calling for the NMFS to close longline fishing in Bluefin spawning areas in the Gulf during the spawning season.
According to Dr. Safina and Earth Justice, there may be even fewer than 10,000 Bluefin left, “This is a charismatic fish species, a major predator that plays a crucial role in the web of oceanic life – but its population is at a dangerously low level. Bluefin populations have been steadily declining for the last 20 years. The Fisheries Service has a responsibility to follow the law, recognize the important scientific discoveries that show the Bluefin spawns during certain times and places when longline fishing is killing off huge numbers of fish, and protect the spawning Bluefin.”
Commercial fishing does most of the damage, but it is not the only culprit. The National Marine Fisheries Service estimates that 23 percent of the total Bluefin tuna killed in the Atlantic are killed for sport. Recreational anglers can also obtain commercial permits, so a great many giant Bluefin currently caught recreationally are marketed commercially; in Massachusetts, recreation charters are routinely run by commercial wholesalers who buy the catch from the “recreational angler”. In our area, a fairly well established charter or party-boat fishery for small Bluefin tuna also exists from the Outer Banks to Rudee Inlet (and actually on up to Massachusetts). There are an estimated 15,000 recreational anglers using this fishery annually, and this is the only U.S. fishery allowed to catch Bluefin that are below the minimum commercial size (1.78 m from tip to tail).
When I think back to when I was a kid, traveling the coasts with my dad, I wonder how it could have ever come to this. The worry is that later generations will be unaware of the abundance that used to be our seas, and the current levels will be viewed as the norm. Fisheries Biologist Daniel Pauley calls this “shifting baselines”, a metric that allows us to shift our notions of a depleted sea without understanding what has actually been lost.
Despite it all, I still enjoy viewing the old photos of proud fisherman standing by these thousand pound giants. They invoke a nostalgic feeling of when we still believed that the sea was indeed limitless. But I would caution us now, that each new photo we take is an image of a fish that will no longer be able to spawn or help propagate its species. As amazing (and fun to catch!) as they are, it’s time to let them be. Avoid charters that go after Bluefin or Marlin. And exercise good judgment; your food choices can make a difference. Ask the fishmonger about where his fish comes from, and don’t buy Bluefin or Swordfish. If you enjoy seafood (especially sushi), ask the chef what kind of tuna is being served. If it’s Bluefin, don’t order it.
The downward trend can be turned around, but only by employing restraint and common sense; in short, a sea ethic that preserves the integrity, stability, and beauty of the ocean and the creatures that live in it.
The great Bluefin Tuna is in danger of collapse and on the brink of extinction, and as reported by the Virginia Pilot, a U.S. proposal to temporarily ban bluefin fishing in the Eastern fishery to allow the species to recover was overwhelmingly rejected the International Commission for the Conservation of Atlantic Tunas (ICCAT) Ironically, this same commission also reports that nearly forty years of overfishing have depleted the stock of these giants to just 3% of its 1960 totals - a decline of 97%. Atlantic White Marlins are down to 6%, and Atlantic Blue Marlins have been driven to 20% of previous abundance. Intensified research has led to a better understanding of the Bluefin, but recent assessments show the population is at its lowest recorded levels, at the same time that fishing pressure is at its highest. Dockside reports from Atlantic fishers confirm what the scientific reports show – the Western Atlantic Bluefin populations continue to decline.
The great Bluefin Tuna are magnificent fish; they average ten feet in length and can weigh over 1,500 pounds. Atlantic Bluefin are warm-blooded ("homeothermic ") and are therefore able to regulate their body temperatures, which allows them to thrive in colder waters. Exceptional swimmers, they have been known to achieve speeds up to 20 knots and have been timed crossing the Atlantic Ocean in thirty days or less. They also have the ability to dive up to 3,000 feet in a matter of minutes. Unlike most tunas, Bluefin grow slowly and mature late, making them more vulnerable to intensive fishing. Demand is high since it is especially popular in sushi and sashimi dishes. In Japan, they can command prices of up to $100,000, (it is curious that ICCAT rejected the U.S. proposal, and instead adopted a Japanese proposal that requested that nations that fish the Eastern bluefin fishery submit a report to the commission that details how they are complying with the 2006 fishing plan that's in place.).
Note: Canned tuna purchased in the super market is most likely Yellowfin, Skipjack, Albacore or Bigeye (mostly the non-schooling fish).
According to Carl Safina of Blue Ocean Institute, the major cause for the decline of Bluefins is the unrestrained use of non-selective fishing gear, mainly pelagic longlines and seine or drift gillnets. Pelagic longlines can be over 25 miles in length and set with thousands of hooks. These nets and lines accidentally capture unmarketable juveniles; the majority of these fish are already dead when they reach the vessel. In many cases, the bycatch and bykill is larger than the actual number of marketable target fish caught.
But there are efforts to save the Bluefin. Earthjustice, on behalf of Blue Ocean Institute and Carl Safina, filed a lawsuit challenging the failure of the National Marine Fisheries Service (NMFS) to limit longline fishing in the Gulf of Mexico. Dr. Safina is calling for the NMFS to close longline fishing in Bluefin spawning areas in the Gulf during the spawning season.
According to Dr. Safina and Earth Justice, there may be even fewer than 10,000 Bluefin left, “This is a charismatic fish species, a major predator that plays a crucial role in the web of oceanic life – but its population is at a dangerously low level. Bluefin populations have been steadily declining for the last 20 years. The Fisheries Service has a responsibility to follow the law, recognize the important scientific discoveries that show the Bluefin spawns during certain times and places when longline fishing is killing off huge numbers of fish, and protect the spawning Bluefin.”
Commercial fishing does most of the damage, but it is not the only culprit. The National Marine Fisheries Service estimates that 23 percent of the total Bluefin tuna killed in the Atlantic are killed for sport. Recreational anglers can also obtain commercial permits, so a great many giant Bluefin currently caught recreationally are marketed commercially; in Massachusetts, recreation charters are routinely run by commercial wholesalers who buy the catch from the “recreational angler”. In our area, a fairly well established charter or party-boat fishery for small Bluefin tuna also exists from the Outer Banks to Rudee Inlet (and actually on up to Massachusetts). There are an estimated 15,000 recreational anglers using this fishery annually, and this is the only U.S. fishery allowed to catch Bluefin that are below the minimum commercial size (1.78 m from tip to tail).
When I think back to when I was a kid, traveling the coasts with my dad, I wonder how it could have ever come to this. The worry is that later generations will be unaware of the abundance that used to be our seas, and the current levels will be viewed as the norm. Fisheries Biologist Daniel Pauley calls this “shifting baselines”, a metric that allows us to shift our notions of a depleted sea without understanding what has actually been lost.
Despite it all, I still enjoy viewing the old photos of proud fisherman standing by these thousand pound giants. They invoke a nostalgic feeling of when we still believed that the sea was indeed limitless. But I would caution us now, that each new photo we take is an image of a fish that will no longer be able to spawn or help propagate its species. As amazing (and fun to catch!) as they are, it’s time to let them be. Avoid charters that go after Bluefin or Marlin. And exercise good judgment; your food choices can make a difference. Ask the fishmonger about where his fish comes from, and don’t buy Bluefin or Swordfish. If you enjoy seafood (especially sushi), ask the chef what kind of tuna is being served. If it’s Bluefin, don’t order it.
The downward trend can be turned around, but only by employing restraint and common sense; in short, a sea ethic that preserves the integrity, stability, and beauty of the ocean and the creatures that live in it.
Thursday, January 10, 2008
Final rule announced for Atlantic Scallop Fisheries
NMFS issues this final rule to approve and implement measures contained in Framework Adjustment 20 (Framework 20) to the Atlantic Sea Scallop Fishery Management Plan (FMP). This action maintains the trip allocations and possession limits established by the interim measures that were enacted by NMFS on June 21, 2007, for the Elephant Trunk Access Area (ETAA) in 2007 to reduce the potential for overfishing the Atlantic sea scallop (scallop) resource and excessive scallop mortality. This action reduces the number of scallop trips to the ETAA, and prohibits the retention of more than 50 U.S. bushels (17.62 hL) of in-shell scallop outside ot the boundaries of the ETAA (deckloading).
This action maintains the trip allocations and possession limits enacted by NMFS on June 21, 2007, for the Elephant Trunk Access Area (ETAA) in 2007 to reduce the potential for overfishing the Atlantic sea scallop (scallop) resource and excessive scallop mortality. This action reduces the number of scallop trips to the ETAA, and prohibits the retention of more than 50 U.S. bushels (17.62 hL) of in-shell scallop outside of the boundaries of the ETAA (deckloading). The action also clarifies that the current restriction on landing no more than one scallop trip per calendar day for vessels fishing under general category rules does not prohibit a vessel from leaving on a scallop trip on the same calendar day that the vessel landed scallops.
This action maintains the trip allocations and possession limits enacted by NMFS on June 21, 2007, for the Elephant Trunk Access Area (ETAA) in 2007 to reduce the potential for overfishing the Atlantic sea scallop (scallop) resource and excessive scallop mortality. This action reduces the number of scallop trips to the ETAA, and prohibits the retention of more than 50 U.S. bushels (17.62 hL) of in-shell scallop outside of the boundaries of the ETAA (deckloading). The action also clarifies that the current restriction on landing no more than one scallop trip per calendar day for vessels fishing under general category rules does not prohibit a vessel from leaving on a scallop trip on the same calendar day that the vessel landed scallops.
Tuesday, May 8, 2007
IATTC Advisory Committee to Meet; May 30 in Long Beach, CA
The General Advisory Committee to the U.S. Section to the Inter-American Tropical Tuna Commission (IATTC) will meet on May 30, 2007, in Long Beach, CA. The committee will discuss the following issues: 1) 2006 and 2007 IATTC activities; 2) status of the stocks and status of the fishery in 2006; 3) meetings of the IATTC and its working groups; 4) possible conservation and management measures for yellowfin and bigeye tuna in 2007 and beyond; 5) measures to be taken in cases of non-compliance with the IATTC's conservation and management measures; 6) management of fishing capacity; 7) measures to address bycatch (such as juvenile tunas, sea turtles, seabirds, and sharks); 8) financial issues pertinent to the financial solvency of the IATTC; 9) IATTC cooperation with other regional fishery management organizations; and 10) Advisory Committee operational issues. For more information, read the Federal Register notice.
Thursday, April 19, 2007
Protect Local Shark Populations
Protect our Coastal Shark Population
As the summer fishing season begins, all anglers, sport and commercial, should consider the plight of declining shark populations and the effects that the heavy fishing of them is having on the ecosystem. Fewer big sharks in the oceans mean that bay scallops, oysters and other shellfish may be damaged, tying unlikely members of the marine ecosystem to the same fate. A study by Dalhousie University has found that over fishing the largest predatory sharks, such as the bull, blue, dusky, and hammerhead has led to the rapid expansion of ray, skate, and small shark prey species. Large sharks have been functionally eliminated from the east coast, no longer performing their ecosystem role as top predators. Fewer big sharks mean there are more of the fish they once ate, such as the Cownose ray.
With an average population increase of about eight percent per year, the east coast Cownose ray population may now number as many as 40 million. Cownose can grow to be more than four feet across, eat large quantities of bivalves, including bay scallops, oysters, soft-shell and hard clams in the bays and estuaries they use for habitat in the summer and spring. This increased predation by cownose rays inhibits the recovery of oysters and clams which are already damaged by overexploitation, disease, habitat destruction, and pollution. By 2004, Cownose rays had completely devastated North Carolina’s scallop population, collapsing a centuries-old fishery.
As many as 73 million sharks are killed worldwide each year for the finning trade, and the number is rising. Growing demand for shark fins and meat has led to increased fishing, but a large number are caught accidentally as "by catch" by fisherman after other types of fish. According to Carl Safina of Blue Ocean Institute, 75% of all fish are captured as by catch. The danger for Sharks (and other elasmobranches) posed by increased fishing pressure, is that they are long-lived, slow to mature, and produce few offspring. Aggressive fishing can take a toll much more quickly on sharks than other fish.
Ecologists have long held that maintaining the populations of top predators is critical for sustaining healthy oceanic ecosystems; its organisms are interconnected, and changes at one level have implications at others. An Ecosystem based view of fisheries management states the necessity of protecting species such as sharks as a primary player in the overall health of the ecosystem.
But, sharks are also a protected species. The Shark Finning Prohibition Act was signed into law on December 21, 2000. The Act prohibits people under U.S. jurisdiction from: (1) engaging in shark finning at sea; (2) possessing shark fins aboard a fishing vessel without the corresponding carcass; or (3) landing shark fins without the corresponding carcass. And according to NOAA’s Regulatory Changes in Amendment 1 to the Fishery Management Plan for Atlantic Tunas, Swordfish, and Sharks, several species of pelagic and coastal sharks are protected by Time and Area Closures for commercial vessels with bottom longline gear on board from January through July off North Carolina.
A map of the closed shark areas can be found at: http://www.nmfs.noaa.gov/sfa/hms/images/HMS_Closed_Areas_w_Bathymetry.jpg
Yet, without increased enforcement of existing regulations, big sharks may be fished to extinction. As sportsman, waterman, and stewards of our oceans, it is our duty to protect our Living Marine Resources and report violations. To help engage the public, the NOAA Office of Law Enforcement adopted COPPS (Community Oriented Policing and Problem Solving) as a national initiative, designed to empower communities and individuals to actively participate in their local marine conservation management. The NOAA Fisheries Enforcement Hotline (1-800-853-1964) provides live operator coverage 24 hours a day, 7 days a week for anyone in the United States to report a federal fisheries violation.
I know it’s difficult to worry about the fate of sharks, but losing these top predators is having a devastating effect on our home waters, damaging the already fragile shell fish habitats and sea grass. This summer, a catch and release policy for sharks should be in every angler’s toolbox. Also, be on the lookout for illegal fishing activities. Sharks matter, so please report any and all violations to the NOAA COPS hotline at 1-800-853-1964.
As the summer fishing season begins, all anglers, sport and commercial, should consider the plight of declining shark populations and the effects that the heavy fishing of them is having on the ecosystem. Fewer big sharks in the oceans mean that bay scallops, oysters and other shellfish may be damaged, tying unlikely members of the marine ecosystem to the same fate. A study by Dalhousie University has found that over fishing the largest predatory sharks, such as the bull, blue, dusky, and hammerhead has led to the rapid expansion of ray, skate, and small shark prey species. Large sharks have been functionally eliminated from the east coast, no longer performing their ecosystem role as top predators. Fewer big sharks mean there are more of the fish they once ate, such as the Cownose ray.
With an average population increase of about eight percent per year, the east coast Cownose ray population may now number as many as 40 million. Cownose can grow to be more than four feet across, eat large quantities of bivalves, including bay scallops, oysters, soft-shell and hard clams in the bays and estuaries they use for habitat in the summer and spring. This increased predation by cownose rays inhibits the recovery of oysters and clams which are already damaged by overexploitation, disease, habitat destruction, and pollution. By 2004, Cownose rays had completely devastated North Carolina’s scallop population, collapsing a centuries-old fishery.
As many as 73 million sharks are killed worldwide each year for the finning trade, and the number is rising. Growing demand for shark fins and meat has led to increased fishing, but a large number are caught accidentally as "by catch" by fisherman after other types of fish. According to Carl Safina of Blue Ocean Institute, 75% of all fish are captured as by catch. The danger for Sharks (and other elasmobranches) posed by increased fishing pressure, is that they are long-lived, slow to mature, and produce few offspring. Aggressive fishing can take a toll much more quickly on sharks than other fish.
Ecologists have long held that maintaining the populations of top predators is critical for sustaining healthy oceanic ecosystems; its organisms are interconnected, and changes at one level have implications at others. An Ecosystem based view of fisheries management states the necessity of protecting species such as sharks as a primary player in the overall health of the ecosystem.
But, sharks are also a protected species. The Shark Finning Prohibition Act was signed into law on December 21, 2000. The Act prohibits people under U.S. jurisdiction from: (1) engaging in shark finning at sea; (2) possessing shark fins aboard a fishing vessel without the corresponding carcass; or (3) landing shark fins without the corresponding carcass. And according to NOAA’s Regulatory Changes in Amendment 1 to the Fishery Management Plan for Atlantic Tunas, Swordfish, and Sharks, several species of pelagic and coastal sharks are protected by Time and Area Closures for commercial vessels with bottom longline gear on board from January through July off North Carolina.
A map of the closed shark areas can be found at: http://www.nmfs.noaa.gov/sfa/hms/images/HMS_Closed_Areas_w_Bathymetry.jpg
Yet, without increased enforcement of existing regulations, big sharks may be fished to extinction. As sportsman, waterman, and stewards of our oceans, it is our duty to protect our Living Marine Resources and report violations. To help engage the public, the NOAA Office of Law Enforcement adopted COPPS (Community Oriented Policing and Problem Solving) as a national initiative, designed to empower communities and individuals to actively participate in their local marine conservation management. The NOAA Fisheries Enforcement Hotline (1-800-853-1964) provides live operator coverage 24 hours a day, 7 days a week for anyone in the United States to report a federal fisheries violation.
I know it’s difficult to worry about the fate of sharks, but losing these top predators is having a devastating effect on our home waters, damaging the already fragile shell fish habitats and sea grass. This summer, a catch and release policy for sharks should be in every angler’s toolbox. Also, be on the lookout for illegal fishing activities. Sharks matter, so please report any and all violations to the NOAA COPS hotline at 1-800-853-1964.
NOAA publishes final rule on IUU Fishing
NOAA Fisheries has published a final rule to define the term "illegal, unreported or unregulated (IUU) fishing", as required by section 403 of the Magnuson-Stevens Fishery Conservation and Management Reauthorization Act of 2006. For purposes of the Act, this final rule defines "illegal, unreported, or unregulated'' fishing as:
(A) fishing activities that violate conservation and management measures required under an international fishery management agreement to which the United States is a party, including catch limits or quotas, capacity restrictions, and bycatch reduction requirements; (B) overfishing of fish stocks shared by the United States, for which there are no applicable international conservation or management measures or in areas with no applicable international fishery management organization or agreement, that has adverse impacts on such stocks; or (C) fishing activity that has an adverse impact on seamounts, hydrothermal vents, and cold water corals located beyond national jurisdiction, for which there are no applicable conservation or management measures or in areas with no applicable international fishery management organization or agreement.
(A) fishing activities that violate conservation and management measures required under an international fishery management agreement to which the United States is a party, including catch limits or quotas, capacity restrictions, and bycatch reduction requirements; (B) overfishing of fish stocks shared by the United States, for which there are no applicable international conservation or management measures or in areas with no applicable international fishery management organization or agreement, that has adverse impacts on such stocks; or (C) fishing activity that has an adverse impact on seamounts, hydrothermal vents, and cold water corals located beyond national jurisdiction, for which there are no applicable conservation or management measures or in areas with no applicable international fishery management organization or agreement.
Monday, April 2, 2007
Sharks functionally extinct: from CBC news
The overfishing of large shark species off the eastern seaboard of the United States has upset the balance of marine life, a team of Canadian and U.S. scientists says.
"We're chopping off the top of the food chain," said Julia Baum of Dalhousie University in Halifax, co-author of a study outlining the huge decline in big sharks over 35 years.
Overfishing of several species of sharks, including hammerheads, is causing a dangerous ripple effect through the marine food chain, a new study says.Overfishing of several species of sharks, including hammerheads, is causing a dangerous ripple effect through the marine food chain, a new study says.
(Yves Lefebre - Fundacion Malpelo/Associated Press)
Fewer big sharks mean there are more of the fish they once ate, such as the cownose ray.
The population of the rays in Chesapeake Bay has grown by 20 times in 30 years, said Charles Peterson, a professor of marine sciences at the University of North Carolina at Chapel Hill and co-leader of a study published in Science on Friday.
As the rays increase — they may now number 40 million — they have slashed the populations of bay scallops, oysters and soft-shell and hard clams, Baum said. The century-old bay-scallop fishery is now just a memory.
So many sharks have been killed that they are "functionally extinct," which means they can no longer perform their role of controlling middle predators in the marine ecosystem, Baum told CBC News.
The population imbalance shouldn't be a surprise considering the drop in large sharks in recent decades. While they are fished to meet the growing demand for shark fins and meat, the single largest problem is the sharks taken accidentally as "bycatch" by fishermen seeking other species, she said.
As many as 73 million sharks are killed worldwide each year for their fins, and the number is rising rapidly.
The new study, funded by the Pew Institute for Ocean Science, updated a 2003 study by Baum and noted Dalhousie fisheries biologist Ransom A. Myers, who died recently.
The new study concluded that the original estimates of declines in big sharks had been too conservative.
Populations plunge
Now the population of scalloped hammerhead and tiger sharks may have fallen by more than 97 per cent since 1970, while bull, dusky and smooth hammerhead sharks are down by more than 99 per cent.
As the shark populations fell, the fish they once ate boomed and the marine life at the bottom of the food chain — scallops, shrimp, clams — have been ravaged.
The rise of the cownose ray is even affecting the underwater vegetation.
"They're known in the Chesapeake Bay, in their great schools, to excavate and denude large areas of sea grass," Peterson said.
Increased protection for great sharks, including reduced fishing of all shark species and enforcing bans on shark finning, is needed to rebalance the system, Baum said.
"We're chopping off the top of the food chain," said Julia Baum of Dalhousie University in Halifax, co-author of a study outlining the huge decline in big sharks over 35 years.
Overfishing of several species of sharks, including hammerheads, is causing a dangerous ripple effect through the marine food chain, a new study says.Overfishing of several species of sharks, including hammerheads, is causing a dangerous ripple effect through the marine food chain, a new study says.
(Yves Lefebre - Fundacion Malpelo/Associated Press)
Fewer big sharks mean there are more of the fish they once ate, such as the cownose ray.
The population of the rays in Chesapeake Bay has grown by 20 times in 30 years, said Charles Peterson, a professor of marine sciences at the University of North Carolina at Chapel Hill and co-leader of a study published in Science on Friday.
As the rays increase — they may now number 40 million — they have slashed the populations of bay scallops, oysters and soft-shell and hard clams, Baum said. The century-old bay-scallop fishery is now just a memory.
So many sharks have been killed that they are "functionally extinct," which means they can no longer perform their role of controlling middle predators in the marine ecosystem, Baum told CBC News.
The population imbalance shouldn't be a surprise considering the drop in large sharks in recent decades. While they are fished to meet the growing demand for shark fins and meat, the single largest problem is the sharks taken accidentally as "bycatch" by fishermen seeking other species, she said.
As many as 73 million sharks are killed worldwide each year for their fins, and the number is rising rapidly.
The new study, funded by the Pew Institute for Ocean Science, updated a 2003 study by Baum and noted Dalhousie fisheries biologist Ransom A. Myers, who died recently.
The new study concluded that the original estimates of declines in big sharks had been too conservative.
Populations plunge
Now the population of scalloped hammerhead and tiger sharks may have fallen by more than 97 per cent since 1970, while bull, dusky and smooth hammerhead sharks are down by more than 99 per cent.
As the shark populations fell, the fish they once ate boomed and the marine life at the bottom of the food chain — scallops, shrimp, clams — have been ravaged.
The rise of the cownose ray is even affecting the underwater vegetation.
"They're known in the Chesapeake Bay, in their great schools, to excavate and denude large areas of sea grass," Peterson said.
Increased protection for great sharks, including reduced fishing of all shark species and enforcing bans on shark finning, is needed to rebalance the system, Baum said.
Subscribe to:
Comments (Atom)