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A couple of years ago, there was a report that only 10% of the ocean's apex predators remained. Now a report from the Natural Resources Defense League comes out that the popualtion of apex predators has diminished by 50%. I'm sure fishing is not as good as it was 200 years ago, but why the incongruity in the numbers? If these groups want me to believe their reports, they need to get together before they release the data.

 

BTW, a LOT of very large blue marlin have been caught recently off the Bahamas and my friend released one close to a grand off St. Thomas last summer, plus several over 500. Anecdotal? Yes. But it makes it harder for me to believe all this crap.

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I'm not "up" on the studies you refer too, but based on what you wrote, I take it as there is 5% of the predators remaining.

 

50% of 10% = 5%

 

I don't find it hard to believe at all. Where are the top of the food chain, we are good at decimating stocks, but poor at managing those same stocks.

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Ed, I should have been more specific. The second study said, "...in the past 1/2 century". It was not an updated study from the prior one.

 

While I have not been out, there's also talk of more school bluefins this year than in recent memory. It sure is refreshing to hear something positive as opposed to doom and gloom.

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The 50% figure is from 1999. It's possible that a few years later it could be 10%. These fish don't grow that fast and they (the commercial guys) have been taking more and more each year. Any way you cut it, something has to change or there will be no more fish.

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The 50% figure is from 1999. It's possible that a few years later it could be 10%. These fish don't grow that fast and they (the commercial guys) have been taking more and more each year. Any way you cut it, something has to change or there will be no more fish.

 

Actually, pelagic longlining is banned from the Florida Straits to NC. They are not taking more and more fish. The 50% figure is from this week. It was on CNN last night.

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Just read it. You're right the figures are from 1999. There's more to it than meets the eye. Another article suggests that there are a few select places in the ocean where pelagics gather due to water temps, oxygen levels and bait supply. They suggest closing those areas to all fishing. Just another means to garner public support for MPA's.

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I think the return of schoolie bluefins is because they banned pelagic longlines over most of the coast. The longlines were catching too many juvenile bluefin tuna and juvenile swordfish as well as large numbers of blue marlin, white marlin and sailfish.

 

A proposal to bring back "experimental" longline gear was defeated.

 

I hope these stocks bounce back like the stripers have...

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Lots of fluke too. MAJOR cutbacks on the way...

 

Why don't they just make the commercial guys use the same size limits as the rec guys? (New Jersey commercial size: 14", rec size 16.5") Ever wonder why you catch so many shorts?

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You have to be very careful using catch or catch per unit effort data. A shift in how the migration of the HMS changes how much they are exposed to fishing. So such a shift and an increase/decrease in catch (or catch per effort) can lead you to believe that there are more or less of them then there really are.

 

Most stock assessment scientists have moved away from catch and catch per unit effort measures; because you can't really measure effort. 2,000 circle hooks placed these days...with GPS, light/chemical attractants, hydro acoustics, and satellite images...fish a lot more efficiently then they did even 10 years ago.

 

Change the percentage chance of an individual hook catching something, and the analysis totally leads to false conclusions

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Lots of fluke too. MAJOR cutbacks on the way...

 

Why don't they just make the commercial guys use the same size limits as the rec guys? (New Jersey commercial size: 14", rec size 16.5") Ever wonder why you catch so many shorts?

 

The issue is reducing the discard rate. Raise the size limit and the fish go over the side dead. This way they are kept AND counted against a hard quota for the coms. When that limit is reached, then that's it on the com side Overall the amount of fish, by weight, taken by the coms is the same at a 16" or 14". But at 14" less go over the side dead

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Lots of fluke too. MAJOR cutbacks on the way...

 

Why don't they just make the commercial guys use the same size limits as the rec guys? (New Jersey commercial size: 14", rec size 16.5") Ever wonder why you catch so many shorts?

 

The issue is reducing the discard rate. Raise the size limit and the fish go over the side dead. This way they are kept AND counted against a hard quota for the coms. When that limit is reached, then that's it on the com side Overall the amount of fish, by weight, taken by the coms is the same at a 16" or 14". But at 14" less go over the side dead

 

What about rasing the minimum mesh size of the net? Won't that let the shorts thru the net?

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That really depends. While increasing the mesh size does work for most species, it doesn't work so much for flats. I mean think about it for a second..."flat" fish, square or diamond mesh? smile.gif And even when you raise the mesh the net can still clog if the fish hit the net a certain way.

 

It really doesn't matter that the coms have a lower size limit. Unlike the rec side, they have a hard quota....and their fishing stops (within a day) when they hit that quota.

 

Recs could have a 14" limit too in NJ; if they were willing to have a shorter season,lower bag limits. and/or a hard quota

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By Kevin Spear

Orlando Sentinel

Posted July 29 2005, 8:53 AM EDT

 

 

ORLANDO -- Scientists have discovered that one of the world's richest remaining deep-sea fishing grounds lies off Florida's east coast, teeming with a variety of tuna, swordfish, billfish and other ocean predators.

 

"What you have is water that is not too hot, water that is not too cold, has lots of oxygen and a variety of ocean currents," said Ransom A. Myers, a fisheries biologist at Dalhousie University in Halifax, Nova Scotia. "We identified six or so areas of high diversity, but the area off Florida is really special."

 

For a report published online Thursday by the journal Science, Myers and four other researchers from Canada and Europe mined data from decades of hauls by Japanese fishing vessels and correlated that information with ocean temperatures and oxygen levels.

 

A key finding was that there has been a steep decline in the variety of species in the Atlantic Ocean -- by almost 50 percent during the past half-century.

 

The hot spot near Florida also has seen a decline in the variety of species, though not as rapidly, Myers said. Other areas that remain relatively diverse with fish are near the east coast of Australia, near the southern tip of India and near Hawaii.

 

A top marine scientist in Florida, though not familiar with the study, said Atlantic waters near the state are known for the mixing of ocean currents and upwellings that support a rich ecology.

 

"It's a diverse and intense place," said John Ogden, director of the Florida Institute of Oceanography. "We're blessed by that."

 

Before anglers in Florida get excited by the scientists' findings, they should consider the boat trip they would have to take before dropping a hook.

 

Myers said the hot spot is about 200 miles offshore and vulnerable to industrial fishing.

 

"It needs to be protected from international fishing," Myers said.

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