Showing posts with label lobsters. Show all posts
Showing posts with label lobsters. Show all posts

Tuesday, August 30, 2011

Selective Trawl Catches Norway Lobster but Allows Cod to Escape

ScienceDaily (Aug. 29, 2011) — Researchers from DTU Aqua in Denmark have decoded the behaviour of Norway lobsters and cod and used the results to develop a selective trawl. This so-called SELTRA-trawl ensures that fewer cod end up as by-catch in the Norway lobster fishery in the Kattegat.

Despite the fact that the cod fishery in the Kattegat is subject to strict fishing quotas, a substantial amount of cod have ended up as by-catch in the Norway lobster fisheries. But after July 15, 2011, more cod have escaped the lobster trawl. From this date, the Danish Ministry of Food, Agriculture and Fisheries has decided, that all Norway lobster fishing in the Kattegat is to be conducted using a selective trawl, called the SELTRA-trawl.

"The Norway lobster population in the Kattegat is doing well, and the Norway lobster fishery is the most economically important fishery in the Kattegat. In 2010 alone, 1700 tonnes of Norway lobsters were caught here. The cod population, on the other hand, has declined severely in the last 20-30 years. If it had not been possible to reduce the by-catch of cod by implementing the SELTRA-trawl, the Norway lobster fishery would have to be reduced significantly in order to protect the cod," says senior research scientist Niels Madsen from the National Institute of Aquatic Resources (DTU Aqua) in Denmark. He has been in charge of developing and testing the SELTRA-trawl during a project funded by the Ministry of Food, Agriculture and Fisheries and the EU.

The cod escapes
A trawl is a funnel-shaped net, which distends when it is pulled after a vessel. When it is pulled along the bottom of the sea, it catches Norway lobsters and bottom-dwelling fish on its way. The catch then falls back towards the rearmost end of the trawl and ends up in the so-called codend.

The challenge for the researchers at DTU Aqua has been to design a trawl that selectively catches Norway lobsters while letting cod and other unwanted by-catch escape through the meshes. Norway lobsters are relatively small, and a small mesh size is thereby required to retain them in the codend. These small meshes also retain fish the size of or larger than the Norway lobsters which is the reason that previously there has been a great deal of by-catch when fishing Norway lobsters.

The researchers came up with the idea of replacing the traditional round codend with a codend shaped like a square box. This square-shaped box proved to be more stable in the water enabling the researchers to take advantage of the cods' and Norway lobsters' behaviour.

When using this codend, the researchers discovered that the Norway lobsters were passive and preferred the bottom part of the codend, while the cod were more active and had a preference for the upper part of the codend and tried to swim against the current to escape.

Based on the knowledge of the differences in behaviour, the researchers at DTU Aqua created the so-called sorting box that has a larger mesh size and is placed in the front end of the SELTRA-trawl allowing the cod to escape. Thereby, they had come up with the basic idea for the SELTRA-trawl.

To be placed on the fishermen's own trawl
In order to keep the costs of the SELTRA-trawl relatively low, the SELTRA-trawl was developed to be added to the fishermen's own trawl:

"The fishermen fishing for Norway lobsters has their own trawl already, and all they need to do is to place the seven meter long SELTRA-trawl with the sorting box and the square codend instead of the rearmost part of their own trawl. In this way, the fishermen do not have to buy a complete new trawl," explains Niels Madsen.

Testing the trawl
Project SELTRA was initiated in 2005 and completed in the end of 2008. Since then, the SELTRA-trawl has been tested in the Norwegian company SINTEF's flume tank at the North Sea Science Park in Hirtshals.

"Through the co-operation with the Danish Fishermen's Association, fishermen and net makers we got ideas on how to design the SELTRA-trawl, so that it is convenient and useful for the fishermen and easy to construct for the net makers," says Niels Madsen.

The SELTRA-trawl has been used on commercial fishing vessels in the so-called closed areas in the Kattegat. The closed areas are areas, in which the Danish Ministry of Food, Agriculture and Fisheries has prohibited cod fishing in order to protect spawning cod.

"In some places in the closed areas, the fishermen have been required to use the SELTRA-trawl when fishing for Norway lobsters. The fishermen, who have now used the SELTRA-trawl for a couple of years, say that they have not experienced significant reductions in the amount of Norway lobsters that they catch," says Niels Madsen and continues:

"Furthermore, the SELTRA-trawl has proved to allow the main part of the cod to escape. During the development work and the following tests we have seen up to 90 % of the cod escape from the SELTRA-trawl."
http://www.sciencedaily.com/releases/2011/08/110829084325.htm

Sunday, August 14, 2011

Albino lobster among catch of unusual species

A “ONE in 100 million” albino lobster, a snipe eel and a wreckfish are among a medley of unusual marine species caught by Irish fishermen over several weeks.

A separate lobster with two crusher claws instead of one has also been landed, along with a sea lamprey, according to Sea Fisheries Protection Authority officers Siubhán Ní Churraidhín and Declan MacGabhann.

The female white/albino lobster, named “Victoria” by her captors, was caught by Declan Clinton and crew on the Virtuous , while fishing for prawns some 34 miles east of Clogherhead, Co Louth, and landed into Howth, Co Dublin, on Thursday night.

Experts estimate there is a one in 100 million chance of making such a catch, according to Mr MacGabhann, who says “Victoria” is only the fifth albino lobster recorded in the last century in Irish waters.

Earlier this year an orange lobster – named “Billy” after the infamous Dutch king – was landed by Séamus Kirk of Clogherhead.

Local fisherman quipped at the time that the xanthochromic lobster was reacting to the election of Sinn Féin president Gerry Adams in the Louth constituency, and heading North.

It had a 30 in a million chance of being caught, Mr MacGabhann told The Irish Times .

“Victoria” is on display at the Sea Life centre in Bray, Co Wicklow, while “Billy” is attracting as much interest as the new resident penguins at the Mara Beo aquarium in Dingle, Co Kerry. A bright blue lobster (one in three million) was found earlier this month off the Clare coast by fisherman Gerry Sweeney.

Not to be outdone, the west coast has also created a few new records.

A male lobster with normal rusty red pigmentation but with two crusher claws instead of one has been found in a pot by currach skipper Mattie Conneely off Rossaveal. It has been donated to Galway Atlantaquaria in Salthill.

US marine scientists writing of this phenomenon in the Journal of Experimental Zoology said that only one of the paired crushers behaves as a normal crusher.

“The other claw has only the appearance of a crusher claw but behaves as a cutter claw,” marine expert at the Sea Fisheries Protection Authority, Declan Quigley, has said.

Ms Ní Churraidhín, officer with the authority at Rossaveal, has been inundated with other specimens in the past couple of weeks, including a snipe eel caught on the Porcupine Bank by Ray Healy and Paul Conneely of the Maria Magdalena III .

The snipe eel ( Nemichthys scolopaceus ) was first recorded in Irish waters in May 1935, according to Mr Quigley, and there are only 27 known records of it here to date. He notes that their size may allow them to slip through the mesh of trawls, and they could also be discarded as having no commercial value.

A wreckfish and an unusual crustacean with no eyes, which may be a polychelid lobster, were also caught by Seánín Ned Ó Flatharta of the Glór na dTonn fishing vessel.

The wreckfish ( Polyprion americanus ) was caught on the Porcupine. The deep-water species inhabits caves and shipwrecks – hence its name. The Galway vessel Maggie C recorded a similar specimen a year ago.

The wreckfish was bought by Stephane Griesbach of Gannet Fishmongers and sold on to Oscar’s restaurant in Galway city, according to Ms Ní Churraidhín.

The sea lamprey was found attached to trawl doors of the Sean Oisín fishing vessel while also working on the Porcupine, according to Ms Ní Churraidhín. The vessel has just completed a survey for prawns on the bank.

Lampreys, which are often found in rivers, are regarded as very rare so far offshore, she says.

http://www.irishtimes.com/newspaper/ireland/2011/0813/1224302379306.html

Friday, May 6, 2011

Claw Machines In St. Paul Bars Boast Live Lobsters

May 5, 2011 5:02 PM

ST. PAUL, Minn. (AP) — The claw machines in two St. Paul bars boast something quite different than the typical stuffed animal — they’ve got live lobsters.

For $2 a pop, customers at Shamrocks Grill and Pub can try their hand at winning their very own lobster. If they do, the kitchen staff cooks it for them and serves it with broccoli and bread.

But Minnesota Public Radio reports that can quickly turn into $20, as the lobsters are difficult to catch.

There’s another one at Tiffany Sports Lounge in St. Paul, and the distributor has plans for two more, including one at Burrito Loco in Minneapolis.

Although similar operations have drawn complaints from animal rights groups in other states, distributor Cliff Hentz said they’re treated no differently than the lobsters at Red Lobster.

http://minnesota.cbslocal.com/2011/05/05/claw-machines-in-st-paul-bars-boast-live-lobsters/

Friday, October 15, 2010

Shellfish Surprise: Aquarium Unveils Blue, Calico and Pumpkin Lobsters

There's a rainbow of rarity on display at a Connecticut aquarium, as lobsters of some truly different hues share a tank for perhaps the first time ever.


There's a blue one, a pumpkin-colored one and even a calico critter just to spice things up.

"It's the colors of fall," said Dave Sigworth, spokesman for the Maritime Aquarium in Norwalk, Conn., which has the unique trio on display.

The odds of seeing these three together are roughly 1 in 900 quintillion -- but a series of timely donations has allowed Connecticut's Maritime Aquarium to put together one of the most unusual lobster displays ever. While the blue lobster is a one in a million catch, the orange and calico are even rarer -- with the odds of finding them roughly 1 in 30 million.

The blue lobster is the most common of the lot -- the odds of finding one of those are merely 1 in a million. Sigworth says the aquarium is offered a blue lobster roughly once a year.

But the odds of finding an orange or calico lobster are around 1 in 30 million -- each.

"I wasn't even aware you could have an orange one," Sigworth said. "The chances of seeing them together at one time in one tank are astronomical."

In fact, Norwalk Community College math professor Joe Karnowski told the Republican-American newspaper that the odds of seeing all three together are 1 in 900 quintillion -- so you might say the Maritime Aquarium hit the shellfish jackpot.

Sigworth said the lobsters were donated by local seafood markets and lobstermen who realized they had some truly special shellfish.

But like people, the colors of the lobsters run only shell deep -- inside, they're the same as any other lobster.

"They're completely normal lobsters in every other way," Sigworth said. "If you put them in a pot of boiling water, they would turn red like any other lobster. And from what I understand, they would taste the same."

Nearly 100 million pounds of lobster are caught in U.S. waters annually, with most of them -- 78 million pounds last year -- caught off Maine, according to the National Marine Fisheries Service.

While lobster populations are abundant in the Gulf of Maine and nearby Georges Bank, they've suffered from a combination of overfishing and warmer waters in southern New England, where just 15 million lobsters are estimated to remain, down from 35 million a decade ago.

Some experts have even proposed a five-year ban on lobster fishing from Massachusetts' Cape Cod to Virginia to help the population recover -- a move opposed by local fishermen, who say jobs would be lost.

Ed Mazza Contributor

Shellfish Surprise: Aquarium Unveils Blue, Calico and Pumpkin Lobsters

There's a rainbow of rarity on display at a Connecticut aquarium, as lobsters of some truly different hues share a tank for perhaps the first time ever.


There's a blue one, a pumpkin-colored one and even a calico critter just to spice things up.

"It's the colors of fall," said Dave Sigworth, spokesman for the Maritime Aquarium in Norwalk, Conn., which has the unique trio on display.

The odds of seeing these three together are roughly 1 in 900 quintillion -- but a series of timely donations has allowed Connecticut's Maritime Aquarium to put together one of the most unusual lobster displays ever. While the blue lobster is a one in a million catch, the orange and calico are even rarer -- with the odds of finding them roughly 1 in 30 million.

The blue lobster is the most common of the lot -- the odds of finding one of those are merely 1 in a million. Sigworth says the aquarium is offered a blue lobster roughly once a year.

But the odds of finding an orange or calico lobster are around 1 in 30 million -- each.

"I wasn't even aware you could have an orange one," Sigworth said. "The chances of seeing them together at one time in one tank are astronomical."

In fact, Norwalk Community College math professor Joe Karnowski told the Republican-American newspaper that the odds of seeing all three together are 1 in 900 quintillion -- so you might say the Maritime Aquarium hit the shellfish jackpot.

Sigworth said the lobsters were donated by local seafood markets and lobstermen who realized they had some truly special shellfish.

But like people, the colors of the lobsters run only shell deep -- inside, they're the same as any other lobster.

"They're completely normal lobsters in every other way," Sigworth said. "If you put them in a pot of boiling water, they would turn red like any other lobster. And from what I understand, they would taste the same."

Nearly 100 million pounds of lobster are caught in U.S. waters annually, with most of them -- 78 million pounds last year -- caught off Maine, according to the National Marine Fisheries Service.

While lobster populations are abundant in the Gulf of Maine and nearby Georges Bank, they've suffered from a combination of overfishing and warmer waters in southern New England, where just 15 million lobsters are estimated to remain, down from 35 million a decade ago.

Some experts have even proposed a five-year ban on lobster fishing from Massachusetts' Cape Cod to Virginia to help the population recover -- a move opposed by local fishermen, who say jobs would be lost.

Ed Mazza Contributor

Sunday, September 19, 2010

Freak lobster with two cutting claws has new friend - with two crushing claws

A million-to-one freak lobster with two cutting claws caught in British waters has found a friend in another mutant crustacean -- with two crushing claws.


Lobsters usually have one cutting claw and one crushing claw - which are each used to catch food such as crabs.

They grab their prey with the sharp cutting claw while the powerful crusher claw is used to break open the shell.

But a lobster - nicknamed Popeye - with two crushing claws has now been found by fisherman Steven Tregeer off St Just in Cornwall.

The discovery comes just weeks after a lobster dubbed 'Edward Scissorhands' with two cutting claws was found off the coast of nearby Mylor.

The pair of freak crustaceans are now being cared for at Newquay's Blue Reef Aquarium.

Blue Reef's David Waines said: ''On his own Edward was an extremely unusual find.

''So for Popeye to have been caught within the space of just a few weeks is nothing short of extraordinary.

''We now have a pair of lobsters with the correct number of cutting and crushing claws - the only problem is they're the wrong way round.''

Lobsters are among the planet's oldest inhabitants with fossil remains found dating back more than 100 million years.

Their prey consists of crabs, which are grabbed by the legs using the cutter claw while the crusher claw is usually used to break open the carapace.

Freak lobster with two cutting claws has new friend - with two crushing claws

A million-to-one freak lobster with two cutting claws caught in British waters has found a friend in another mutant crustacean -- with two crushing claws.


Lobsters usually have one cutting claw and one crushing claw - which are each used to catch food such as crabs.

They grab their prey with the sharp cutting claw while the powerful crusher claw is used to break open the shell.

But a lobster - nicknamed Popeye - with two crushing claws has now been found by fisherman Steven Tregeer off St Just in Cornwall.

The discovery comes just weeks after a lobster dubbed 'Edward Scissorhands' with two cutting claws was found off the coast of nearby Mylor.

The pair of freak crustaceans are now being cared for at Newquay's Blue Reef Aquarium.

Blue Reef's David Waines said: ''On his own Edward was an extremely unusual find.

''So for Popeye to have been caught within the space of just a few weeks is nothing short of extraordinary.

''We now have a pair of lobsters with the correct number of cutting and crushing claws - the only problem is they're the wrong way round.''

Lobsters are among the planet's oldest inhabitants with fossil remains found dating back more than 100 million years.

Their prey consists of crabs, which are grabbed by the legs using the cutter claw while the crusher claw is usually used to break open the carapace.