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bababooey
05-22-2009, 03:15 PM
:learn:This isn't news to me. Every trip out we have to run from the dogfish. There are now more dogfish than I have ever seen since I started fishing. It's about time to really take a look at the numbers.



Threat of Dogfish Sharks Unite Commercial and Recreational Fishermen From Maine to North Carolina



TRENTON, N.J., May 4 /PRNewswire/ -- An unprecedented alliance of commercial, recreational and party/charter boat fishermen and associated businesses has formed Fishermen Organized for Rational Dogfish Management (FORDM) to deal with a looming crisis. FORDM has requested assistance from Dr. Jane Lubchenco, newly appointed National Oceanic and Atmospheric Administration head, in dealing with an out-of-balance population of highly predatory spiny dogfish that is depleting other Northeast and Mid-Atlantic fisheries. Scientists estimate their biomass at up to four billion pounds.

The classic Fishes of the Gulf of Maine says of this shark species, "voracious almost beyond belief, the dogfish entirely deserves its bad reputation. Not only does it harry and drive off mackerel, herring, and even fish as large as cod and haddock, but it destroys vast numbers of them... they prey on practically all species of Gulf of Maine fish smaller than themselves." Spiny dogfish can exceed 5 feet in length.

The huge population of these ravenous sharks is holding back the recovery of New England groundfish and many others fish stocks, either feeding heavily on the more valuable species or on their prey. In 1992, Dr. Steven Murawski, now National Marine Fisheries Service's chief scientist, wrote, "Given the current high abundance of skates and dogfish, it may not be possible to increase gadoid (cod and haddock) and flounder abundance without 'extracting' some of the current standing stock." The abundance of dogfish today greatly exceeds that of skates, comprising over half of the fish taken in the Northeast Fisheries Science Center's annual trawl surveys.

Conservatively, spiny dogfish require a daily food intake of 1-1/2% of their total body weight. This equates to a minimum of two and a half million metric tons of prey species eaten every year. In 2007 the commercial catch of all species from East coast fisheries was 2/3 of a million metric tons.

Throughout their range spiny dogfish are also seriously interfering with traditional fisheries. According to Ray Bogan, legal counsel for United Boatmen and member of one of New Jersey's oldest party/charter fishing families, there are more spiny dogfish than he has encountered ever before in a lifetime spent on Mid-Atlantic waters, it's impossible to fish in areas that they have seasonally "taken over," and every year they take over more fishing grounds. Hank Lackner, Captain of the F/V Jason & Danielle out of Montauk and participant in a number of government sponsored trawl surveys, reports that spiny dogfish are destroying 10 years of efforts to rebuild other stocks and are overpopulated from the beach to 250 fathoms, from Cape Hatteras to the Canadian line.

**** Grachek, owner of the F/V Anne Kathryn out of Point Judith, relayed a message from Captain Joe Mattera, who had just curtailed a scup trip because of the extraordinary number of dogfish he encountered. His net was plugged with spiny dogfish in five of the seven tows he made. Jim Thompson, a recreational fisherman from Delaware, reported that when wreck fishing he catches 20 spiny dogfish for every targeted fish. According to Cape Codgillnetter Jan Margenson, "The codfish gear we haul is plugged with dogs and the occasional cod we catch is stripped to the bone of flesh. They act just like piranha, only it's our catch that they're eating." Chris Long, a San Francisco resident who comes to fish on Cape Cod for striped bass and tuna for five days every three weeks in the spring and summer, is now "doing (fresh water) bass fishing in the Cape Ponds" instead.

Craig Banks operates a commercial fishing website. He has spoken with hundreds of recreational and commercial fishermen from New England down to North Carolina about the dogfish issue and says, "The general consensus is that dogfish numbers have been building and now they often make fishing impossible. One of the biggest concerns is the voracious appetite of the hordes of dogs that travel the coast, eating everything in their path." And Rich Ruais, Executive Director of organizations whose members target tuna, reports, "There is not a doubt in any tuna fisherman's mind that the abundance of dogfish throughout the Northeast has severely impacted tuna catches over the last decade. If action is not taken soon to control the hoard of dogfish, the ecosystem in general and the migratory habits of bluefin tuna in particular may be permanently altered and, in spite of our rigorous conservation efforts, the traditional giant tuna fisheries may be destroyed forever."

According to Jim Donofrio, Executive Director of the Recreational Fishing Alliance and an organizer of FORDM, "Tens of millions of recreational fishermen, tens of thousands of commercial fishermen and the thousands of businesses that depend on them are suffering a double whammy because of a management philosophy distorted by foundation-funded marine 'conservationists' with no regard for fish or fishermen, just the crises they create. As the huge biomass of dogfish is reducing the populations of other, far more valuable species, fishermen are required by law to compensate by catching less of those species. This is becoming increasingly more difficult - and more expensive - because of interference from the ravenous hoards of spiny dogfish."

The Magnuson Act, which establishes federal fisheries policies, has been amended by pressure from rich environmental activist groups, making it virtually impossible for managers to effectively address issues like this. Coastal legislators including New Jersey Congressmen Pallone, Lobiondo and Adler, Massachusetts Congressman Frank and North Carolina Congressman Jones, who are familiar with the untenable position that the federal law puts fisherman in, have introduced legislation, H. R. 1584, Comments (http://www.opencongress.org/bill/111-h1584/text)Close Comments (http://www.opencongress.org/bill/111-h1584/text)Permalink (http://www.opencongress.org/bill/111-h1584/?version=ih&nid=t0:ih:4_h:4_) addressing some of its shortcomings.

Nils Stolpe, another FORDM organizer and Communications Director of Garden State Seafood Association, emphasizes that Dr. Lubchenco now has an opportunity to prove to the fishing community that concerns over her association with the Pew Charitable Trusts are unfounded. "Pew is inextricably linked to the advocacy science that seems designed to turn the public and our elected officials against fishermen of every stripe. This will be her first opportunity to demonstrate that she will guide NOAA with a balanced hand, utilizing objective science and fairly serving all of her constituents, fishermen included."

The FORDM letter to Dr. Lubchenco is available at http://www.fishnet-usa.com/dogforum1.htm (http://www.fishnet-usa.com/dogforum1.htm), along with additional fishermen's comments and other material on dogfish.

voyager35
06-29-2009, 10:15 AM
Came across this info. Hope it is ok to post.


"Voracious almost beyond belief, the dogfish entirely deserves its bad reputation. Not only does it harry and drive off mackerel, herring, and even fish as large as cod and haddock, but it destroys vast numbers of them. Again and again fishermen have described packs of dogs dashing among schools of mackerel, and even attacking them within the seines, biting through the net, and releasing such of the catch as escapes them. At one time or another they prey on practically all species of Gulf of Maine fish smaller than themselves, and squid are also a regular article of diet whenever they are found." (Fishes of the Gulf of Maine, Bigelow, H.B. and W.C. Schroeder, 1953)
A plague of spiny dogfish (Squalus acanthias) is interfering with fisheries in coastal states from Maine to North Carolina. Unprecedented numbers of these voracious predators are clogging nets, stealing bait and ruining the catch in fishery after fishery, needlessly penalizing the affected fishermen and coastal fishing communities. In addition to this direct interference with other fisheries, dogfish are eating vast quantities of much more valuable species, negating the effects of drastic management-mandated fishing effort reductions in those fisheries. Fishermen are sacrificing to conserve extremely important recreational and commercial species and their efforts are doing little more than providing more food for an ever-increasing population of dogfish.
How have we gotten to this sorry state? How have we let a low value species like the spiny dogfish become so plentiful that it is standing in the way of the successful rebuilding of other, far more valuable species and costing the coastal economies of a dozen states tens of millions of dollars? The simple answer is that’s what federal law requires.
Building on similar meetings in Biddeford, Maine and Hyannis, Massachusetts, on September 30th we’ll be bringing together federal, state and regional managers, researchers and commercial, recreational and party/charter boat fishermen most familiar with spiny dogfish to discuss the status of the dogfish stocks, the current situation regarding their depredations on East Coast fish and fisheries, and the expectations for the future. We will also be searching for solutions to the problems they are currently inflicting on virtually every other fishery. Our intention is to prepare and widely distribute the proceedings of the Forum, with the aim of acquainting the public and policy makers with the scope of the dogfish problem and of the need for an effective and immediate solution.
Registration is limited and a minimal fee may be required to partially offset expenses. Please contact Nils Stolpe, the Foum Coordinator, for more information.
Also, if you have any pictures illustrating the impact of dogfish on traditional fisheries or dogfish abundance, please let let us know via the contact information above.
We are planning - barring unforeseen technical difficulties - on having an audio recording of the forum, as well as the Powerpoint presentatyions, available on this website within a week.
The agenda is:


Time



Speaker


Subject





9:15 - 9:30

Nils Stolpe FishNet USA


Welcome




9:30 - 10:00

Paul Rago National Marine Fisheries Service Spiny dogfish - status of the stock


Click here for PDF of presentation (http://www.fishnet-usa.com/Paul_Rago.pdf)



Click here for audio(4.6 mb MP3 file) (http://www.fishnet-usa.com/Audio/Paul_Rago.mp3)


10:10 - 10:40

Jim Armstrong Mid Atlantic Fisheries Management Council


MAFMC Spiny Dogfish Management


Click here for PDF of presentation (http://www.fishnet-usa.com/Jim_Armstrong.pdf)



Click here for audio(5.7 mb MP3 file) (http://www.fishnet-usa.com/Audio/Jim_Armstrong.mp3)


10:50 - 11:20

Chris Vonderweidt Atlantic States Marine Fisheries Commission


ASMFC Spiny Dogfish Management


Click here for PDF of presentation (http://www.fishnet-usa.com/Chris_Vonderweit.pdf)



Click here for audio(2.3 mb MP3 file) (http://www.fishnet-usa.com/Audio/Chris_Vonderweidt.mp3)


11:30 - 12:00

David Pierce Massachusetts Division of Marine Fisheries


Act III, Scene 1: "Cry 'Havoc!', and let slip the dogs of war" between the states and NOAA Fisheries: Are we wedded to a dogfish doomsday scenario, or will ecosystem management spur a new direction for dogfish management and cooperation?


Click here for PDF of presentation (http://www.fishnet-usa.com/David_Pierce.pdf)



Click here for audio(4.8 mb MP3 file) (http://www.fishnet-usa.com/Audio/David_Pierce.mp3)


12:00 - 1:00

Lunch







1:00 - 1:30

Peter Himchak New Jersey Division of Fish and Wildlife


NJ spiny dogfish management and resource monitoring


Click here for PDF of presentation (http://www.fishnet-usa.com/Peter_Himchak.pdf)



Click here for audio(4.1 mb MP3 file) (http://www.fishnet-usa.com/Audio/Peter_Himchak.mp3)


1:40 - 2:10

James Sulikowski University of New England


Dismissing Dogma: Using satellite tag technology to gain new Insights into the horizontal and vertical movement patterns of spiny dogfish.


Click here for PDF of presentation (http://www.fishnet-usa.com/James_Sulikowski.pdf)



Click here for audio(4.6 mb MP3 file) (http://www.fishnet-usa.com/Audio/James_Sulikowski.mp3)


2:20 - 2:50

Roger Rulifson University of Eastern Carolina


Movements and Migrations of East Coast Spiny Dogfish


Click here for PDF of presentation (http://www.fishnet-usa.com/Roger_Rulifson.pdf)



Click here for audio(5.3 mb MP3 file) (http://www.fishnet-usa.com/Audio/Roger_Rulifson.mp3)


3:00 - 3:30

Andrew Minkiewicz Kelley Drye


Spiny dogfish management - administrative and legislative considerations



Click here for audio(3.0 mb MP3 file) (http://www.fishnet-usa.com/Audio/Drew_Minkiewicz.mp3)


3:40 - 4:00

Representative from Northeast Area Monitoring and Assessment Program The NEAMAP Trawl Survey


Click here for PDF of presentation (http://www.fishnet-usa.com/NEAMAP_Data.pdf)




Recreational, commercial and party/charter boat Fishermen from the Gulf of Maine to North Carolina will be discussing the impacts of the explosion of the dogfish stocks on their fisheries between the longer technical presentations

The Dogfish Forum was sponsored by the Fishermen's Dock Cooperative, Lund’s Fisheries, National Fisheries Institute’s Scientific Monitoring Committee, North Carolina Fisheries Association, Recreational Fishing Alliance, United Boatmen of NY & NJ and Viking Village.

http://www.fishnet-usa.com/dogforum1.htm

VSdreams
07-30-2009, 02:17 PM
Mike Laptew went diving off Block Island and all he found were dogfish.http://stripersandanglers.com/Forum/images/icons/icon13.gif Endangered?:ROFLMAO:
mdf9pNvYXQA

finchaser
07-31-2009, 07:41 AM
They wonder why fish stocks are down as dogfish eat every juvenile fish in sight and are now found in places and water temperatures they never use to exist

jonthepain
07-31-2009, 09:36 AM
Dogfish, bunker, draggers, slot limits, it's all interconnected.

crosseyedbass
08-01-2009, 11:05 PM
They wonder why fish stocks are down as dogfish eat every juvenile fish in sight and are now found in places and water temperatures they never use to exist

You are spot on, fin. I did some searching. This data only goes to 2005, but there's no way these figures could be lying. I think enough is enough!

http://www.fishnet-usa.com/dogfishfollies.html




The Dogfish Follies An overview
According to on-the-water observations by a multitude of commercial and recreational fishermen, there are so many spiny dogfish (Squalus acanthias) in the coastal waters from Cape Hatteras to Canada that they are significantly interfering with many of our major fisheries. The latest information from the National Marine Fisheries Service (NMFS) is that the total biomass (based on a 3 year average for 2003 to 2005) was 835 million pounds, but many experienced fishermen believe that these small sharks, which have always been known as nuisance fish, are now present in unprecedented numbers (in the middle 1980s their total biomass approached a million metric tons). They occur in huge schools that make it all but impossible to fish, clogging nets and damaging the commercial catch or taking baited hooks that are meant for targeted species.
Besides interfering with commercial and recreational fisheries, these small sharks – which are notorious for their voracious feeding habits – are efficient predators, both of more valuable fish species and of the organisms that these species feed upon. Dogfish were harvested in our waters by European fleets in the 1960s and early 1970s. This foreign fishery ended with passage of the Magnuson Act in 1976, but with the enthusiastic support and encouragement of the federal government, a domestic fishery aimed at supplying European markets was started in the late 1980s. Continuing into the early 2000s, it was at one point landing as many dogfish as the Soviet Block factory trawlers had been thirty years before. The primary targets of the commercial harvesters were large, predominantly female fish.
To the relief of just about everyone, and to the undoubted benefit of just about every commercially and recreationally important fish species in the western North Atlantic, the spiny dogfish stocks started to decline.
Seems like a classic win-win scenario in the making, doesn’t it? A species that has always been considered at best a nuisance is being reduced in numbers, removing a significant source of natural mortality and reducing fishing pressure on more valuable species while pumping money into the economies of half a dozen coastal states and benefiting our balance of trade?
Not quite. Several years ago the directed commercial fishery for spiny dogfish was closed, the number of dogfish are again increasing dramatically, and each year the recreational and commercial fisheries targeting other species are being more heavily impacted by that increase. All to supposedly benefit a species that has been held in contempt by many generations of fishermen.
Dogfish stocks today
Going back to the 1960s, the Northeast Fisheries Science Center’s (NEFSC) bottom trawl survey series is touted as one of the most comprehensive and reliable sources of information about those fish species living on or near the bottom in the waters off the New England and Mid-Atlantic states. The survey is composed of three annual sampling cruises, one in the spring, one in the fall and one in the winter. On each cruise from 100 (winter) to 350 (spring and fall) offshore stations are sampled with measured and monitored tows of a standardized net. The catch from each station is counted, weighed, measured and recorded. In recent years the various survey results have been made available on the Center’s website (http://www.nefsc.noaa.gov/nefsc/publications/online.htm).

Table #1
http://www.fishnet-usa.com/Images/img3.gif

crosseyedbass
08-01-2009, 11:06 PM
The individual survey reports specifically identify about two dozen separate species _ usually the most common and/or those for which significant fisheries exist. The rest of the catch is lumped together into the catch-all category of "Total-other." Interestingly, and in spite of the doom and gloom predictions of the environmental industry, the total poundage taken each year in the three surveys has been trending upward since 1999, the first year for which the reports are available on line (see Chart #1 below). Unfortunately, much of this upward trend is because of the proliferation of spiny dogfish.
Chart #1
http://www.fishnet-usa.com/Images/img1.gif


For every year that we examined, the species that made up the bulk of the samples - by a significant margin - has been the spiny dogfish.
Chart #2
http://www.fishnet-usa.com/Images/img2.gif


As demonstrated in Table #1 and Chart #2, in the years from 1999 to 2005 spiny dogfish have made up from 49% to 66% of the total sample weight (we took the average of the spring, fall and winter surveys each year to smooth over significant seasonal differences). In 2000, the year that the commercial fishery was essentially closed, the poundage of dogfish in the trawl survey began to increase dramatically.
Are dogfish good neighbors?
In the classic Fishes of the Gulf of Maine (Henry B. Bigelow and William C. Schroeder, 1953), dogfish are described as "voracious almost beyond belief, the dogfish entirely deserves its bad reputation. Not only does it harry and drive off mackerel, herring, and even fish as large as cod and haddock, but it destroys vast numbers of them. Again and again fishermen have described packs of dogs dashing among schools of mackerel, and even attacking them within the seines, biting through the net, and releasing such of the catch as escapes them. At one time or another they prey on practically all species of Gulf of Maine fish smaller than themselves, and squid are also a regular article of diet whenever they are found." And the Food and Agricultural Organization of the United Nations, in its Global Information System Species Fact Sheet, says of dogfish "this shark is a powerful, voracious predator that feeds primarily on bony fishes, and is capable of dismembering rather large prey with its strong jaws and clipper-like teeth. Its bony fish prey includes herring, sardines, menhaden and other clupeids, true smelt (Osmeridae) and their eggs, hake, cod, pollock, ling, haddock and other gadoids, midshipmen, blennies, sand lances, mackerel, porgies, croakers, flatfish and sculpins. It is thought to prey on most available bony fishes smaller than itself, and will often prey heavily on abundant schooling fishes, but newborn dogfish attack herring larger than themselves, as may adults with cod and haddock." Ranging up to four feet in length, spiny dogfish may be larger than all but the very largest of the listed prey species.
We must note here that the Atlantic States Marine Fisheries Commission, the interstate organization responsible for managing spiny dogfish in states' waters (out to three miles) on the Atlantic coast, describes their diet as consisting of "of several commercially important species, such as Atlantic herring, Atlantic mackerel, Loligo and Illex squid, and to a lesser extent cod and haddock."
Having a school of dogfish hanging around seems like the marine equivalent of having the Donner Party spending the winter camped in your back yard.
The dogfish fishery
Recognizing all of this, and that some of the more traditional fisheries were getting a bit crowded, the National Marine Fisheries Service started to encourage the development of a dogfish fishery in the Northeast in the late 1980s. This was accompanied with an ambitious marketing program aimed at identifying spiny dogfish as "Cape shark" and establishing a domestic market.
While the domestic market never took off, a number of U.S. companies became quite successful in catching the larger female dogfish and exporting them to Europe. They were so successful, in fact, that by 1996 the domestic fishery had expanded to the point that over 50 million pounds were landed.
The effect of all those dogfish on other fish stocks?
You've already read about the impacts of spiny dogfish on recreational and commercial fishermen - though much of it has been dismissed as "anecdotal information" by the fisheries management establishment. What of their effects on other fish stocks?
Not too surprisingly for anyone with a grasp of ecosystem dynamics in our coastal waters (and in complete agreement with Bigelow's and Schroeder's and the FAO's description of these pint-sized eating machines), the overall abundance of those species that dogfish prey upon has plummeted as dogfish stocks have increased, and this isn't a phenomena that's been restricted to recent years.
Going back almost 50 years, dogfish and their cousins, the various species of skates (which make up a large part of the "Total-other" category in the NEFSC's trawl surveys and probably have a similar though less dramatic effect on other species) have been undergoing a prolonged population explosion in the waters off the Mid-Atlantic and New England (see Chart #3). While there was a small decline in the skates and spiny dogfish from 1990 to 1997 which can be attributed to the domestic dogfish fishery, this decline has since been reversed.
Chart #3
http://www.fishnet-usa.com/Images/DogfWMF3.JPG

crosseyedbass
08-01-2009, 11:07 PM
Chart 4 below illustrates the 35 year trends, from a relative abundance perspective for the spiny dogfish and from a relative harvest perspective for 11 commercially important fish species, for fisheries from the waters off the Mid-Atlantic and New England. Ten of the eleven species were chosen because they were identified either in Bigelow and Schroeder or by the FAO as being preyed upon by spiny dogfish. We added striped bass because of that species' importance to our recreational fishing colleagues. The annual biomass and harvest levels are expressed as a percentage of the aggregate biomass/harvest for the period. During thirty-five years of stringent management measures involving major reductions in fishing effort, ten of the eleven fisheries (black trend lines) have trended downward, and when the expected rebuilding doesn't take place, the management "solution" is to reduce harvest even further. Of the eleven species, only the landings of croaker were tending upward.
Chart #4
http://www.fishnet-usa.com/Images/img5.gif


(Note that we didn't include two prey species, mackerel and herring, that were mentioned in Bigelow and Schroeder and by the FAO. Landings in both of these fisheries have been on an upswing, but both species are far more abundant than the others and their landings aren't approaching maximum levels.)
The landings of these other species have been declining in spite of managers continuously ratcheting fishing effort downward for all of them for well over a decade. It's difficult to imagine that predation by 400,000 metric tons of voracious spiny dogfish doesn't have a significant effect on all of those prey species, each of which only support total (recreational and commercial) landings in the range of 10 to 20 thousand metric tons a year. Could it be that dogfish predation is more than keeping pace with these efforts at reducing fishing effort?
Researchers Wetherbee and Cortés report that spiny dogfish consume between 0.4% and 2.6% of total body weight per day. If we assume a median level of 1.5% per day, that means each dogfish consumes its own weight in prey species every 60 days, or six times its body weight every year. Thus, it took 2.4 million metric tons of prey to support last year's standing crop of 400,000 tons of spiny dogfish.

The 2004 commercial landings of the 11 listed species were 67,000 metric tons. That's about 3% of the total consumed by spiny dogfish in 2004. How much of that 2.4 million tons was comprised of those 11 species, and what effect did that predation have on rebuilding efforts for those stocks?
When the spiny dogfish stock is fully "rebuilt" to 600,000 metric tons (see below) it will take over 3,000,000 metric tons a year to keep it going. In 2004 the commercial landings of all species (finfish and shellfish) from the Atlantic coastal states were only 750,000 metric tons.
The influence of the overabundance of dogfish and other elasmobranches (sharks, skates and rays) was noted by NMFS' Steve Murawski (now NMFS' Director of Scientific Programs and Chief Science Advisor) in 1992, when he wrote in Multi species size composition: A conservative property of exploited fishery systems (with J.S. Idoine in Journal of Northwest Atlantic Fishery Science, Volume 14: 79-85) "given the current high abundance of skates and dogfish, it may not be possible to increase gadoid (cod and haddock) and flounder abundance without `extracting' some of the current standing stock."
So we've got an ocean that's filled with dogfish, each year they are increasing, they severely interfere with both recreational and commercial fishing, and they're undoubtedly eating large - and increasing - amounts of much more valuable species as well as the food those species depend upon. It seems like the only logical solution to an obvious problem - unless we're willing to allow our waters to remain dominated by low-valued species - would be to increase the harvesting of spiny dogfish, doesn't it? Particularly when you consider the fact that some of the traditional and far more valuable fisheries have been in a protracted decline, despite every effort to reduce fishing pressure on them.
Well, not quite.
Spiny Dogfish management
Amending the Magnuson Fisheries Conservation and Management Act in 1996, the Sustainable Fisheries Act (SFA) implemented a number of measures that removed much of the discretion from the fisheries management establishment and, in many knowledgeable folks' estimation, resulted in ridiculously rigorous protections for spiny dogfish, formerly considered trash fish and a species that should most sensibly come with a government bounty, not government protection.
Because a commercial fishery has existed for dogfish, the dogfish fishery has to be managed. And because it has to be managed under the strictures of the Sustainable Fisheries Act, the stock has to be maintained at a level of high abundance.
According to the SFA, fisheries that can't be harvested at maximum sustainable yield are being overfished, and overfished fisheries must be rebuilt within 10 years. Unfortunately, because of the government encouraged and supported development of the commercial dogfish fishery, there is no way that the stock can be "rebuilt" by restricting the directed fishery. This is because there are so many dogfish that they have become a large part of the bycatch in virtually every other fishery.
The dogfish fishery management plan isn't based on estimates of the amount of dogfish in the ocean, it's based on the proportion of large female dogfish in the population. The Mid-Atlantic Fishery Management Council, which jointly manages the fishery with the New England Council, states on its website "the most recent stock assessment data presented by NEFSC (1998) and the Dogfish Technical Committee indicate that total adult female spiny dogfish stock biomass is currently about 280 million lbs (127,000 mt), well below the stock biomass target of 397 million lbs (180,000 mt) based on a three year moving average of the most recent NEFSC survey data." The biomass target of 180,000 metric tons of large female spiny dogfish is the one the managers are aiming for.
If we assume that the total biomass of spiny dogfish increases at the same rate as the mature females, we're looking at a total biomass of about 600,000 metric tons before the stock is considered to be rebuilt.
In spite of the increase in the biomass of spiny dogfish, in spite of a drastically curtailed commercial fishery, and in spite of dogfish making up almost two thirds by weight of the fish caught in the three NEFSC bottom trawl surveys in 2004, there still isn't a high enough proportion of large females. Hence, in 2000 a yearly quota of 4 million pounds was set. Landings were almost 50 million pounds only four years before.
As the chart below shows, the total biomass of spiny dogfish in recent years has been much higher than it was in the late 60s and throughout the 70s, and it appears as if the spawning stock biomass (mature females) is at approximately the same level today as it was then. The level of landings attributable to foreign vessels in the 70s was at about the same level as domestic landings were during the 90s, and (and perhaps unfortunately for competing stocks) the stock, including females, "recovered" to staggering levels of abundance within 5 or 6 years.
http://www.fishnet-usa.com/Images/img6.gif

crosseyedbass
08-01-2009, 11:10 PM
Dogfish as a cause célèbre
The "plight" of the spiny dogfish was seized upon by anti-fishing zealots, people who are apparently always on the lookout for situations that can be turned into perceived crises, carrying forward their and their supporters' anti-fishing campaigns. So a few years back we saw the advent of a "save the spiny dogfish" bandwagon.
This resulted in ominous pronouncements along the lines of "reproductive females have been mined out, pups are flat-lining and the population may not recover within our lifetimes.... this systematic extermination of a valuable part of the marine ecosystem represents a shameful waste of public resources and sets a dangerous precedent for other exploited ocean species" (the Ocean Conservancy), and "Fishermen and politicians teamed up to promote dogfish consumption…. Speak up for the much-maligned cape shark! Dogfish conservation continues to face an uphill battle due to industry opposition and rampant disrespect for dogfish" (Center for Marine Conservation).
These appeals to save the dogfish, while conveniently failing to mention that a current total biomass of 80,000,000 pounds is pretty far from extinction, invariably include a reference to the species' supposed low fecundity. It's true that they, like all sharks, produce a relatively small number of young each year. While females of some species might produce millions of eggs annually, a dogfish will only give birth to a dozen or so live "pups." This might appear to put dogfish populations at risk, particularly when compared to other species. However, for every half million eggs released by a female cod, only an infinitesimal number will survive to the size of a newly born juvenile dogfish, 8 to 11 inches in length. The juvenile dogfish, on the other hand, is a completely functional and efficient predator from birth. While far fewer dogfish are produced per breeding female, each pup is many thousands of times more likely to reach maturity.
Many of the fish species that dogfish prey upon or compete with are tremendously important to both the commercial and recreational fisheries in the Northeast, and to the consuming public. When market conditions are right, codfish and haddock and the various flounders can return several dollars a pound to the fishermen that land them, and they provide sport _ and table fare _ to millions of sportsfishermen. Restored groundfish and other stocks would pump additional hundreds of millions of dollars into the coastal economies of the Mid-Atlantic and New England states. It seems inarguable that their stocks are being both directly and indirectly impacted by the presence of hundreds of millions of pounds of ravenous dogfish. But the anti-fishing campaigners have been hard at work convincing anyone who will listen _ unfortunately, that includes a lot of media folks - that those stocks aren't rebuilding solely because of continued overfishing.
The need for change
The dogfish dilemma that the recreational and commercial fishermen in the Northeast are facing is one of the most compelling examples of what we are doing wrong in fisheries management. Through the Sustainable Fisheries Act in particular we have forced managers into a lockstep aproach to managing our fisheries, based on the erroneous assumption that they all can be and should be managed in the same manner, with the same strictures, and to the same end. Thanks to successful campaigning by anti-fishing activists, most of the subjective judgment has been removed from fisheries management, and they are targeting what little remains.
You don't need an advanced degree in biology to know that competing species can't all be present in a given area at maximum population levels, yet that's what modern fisheries management - at least as it is practiced in the United States - demands. And if any management body attempts to recognize this fact, the guaranteed result is an immediate lawsuit funded by one or another of the "charitable" foundations supporting the various anti-fishing organizations.
You don't need an advanced degree in economics to know that development pressures along most of the 12,000 miles of U.S. coastline are such that once gone, commercial fishing infrastructure is never coming back, and that economic pressures are already threatening the future of much of that infrastructure. Yet rigid adherence to arbitrary rebuilding schedules - particularly if they are biologically impossible to meet - will do nothing but add to those economic pressures.
And you don't need a degree - advanced or otherwise - in any discipline to know that commercial fishermen are far less in need of protection from themselves then they are from the zealots who disingenuously proclaim that their multi-million dollar campaigns to "save" the fisheries will ensure that things will be better for those fishermen in the future.


References:
NEFSC Spiny Dogfish Advisory Report - http://www.nefsc.noaa.gov/nefsc/publications/crd/crd0317/spinydogfish.pdf (http://www.nefsc.noaa.gov/nefsc/publications/crd/crd0317/spinydogfish.pdf)
NEFSC Status of Fishery Resources: Spiny Dogfish - http://www.nefsc.noaa.gov/sos/spsyn/op/dogfish/ (http://www.nefsc.noaa.gov/sos/spsyn/op/dogfish/)
Fishes of the Gulf of Maine - http://www.gma.org/fogm (http://www.gma.org/fogm)
United Nations' Global Information System Species Fact Sheet, http://www.fao.org/figis/servlet/species?fid=2834 (http://www.fao.org/figis/servlet/species?fid=2834) Lovgren, Jim, Fishing Responsibly for Dogfish - http://www.fishnet-usa.com/lovgrenpaper.pdf (http://www.fishnet-usa.com/lovgrenpaper.pdf)

Wetherbee, B.M. and E. Cortes. 2004. Food consumption and feeding habits. pp. 223-244 in: Biology of sharks and their relatives. Musick, J.A., J.C. Carrier and M. Heithaus, eds. http://www.sefscpanamalab.noaa.gov/shark/pdf/1514_C08.pdf (http://www.sefscpanamalab.noaa.gov/shark/pdf/1514_C08.pdf)