Barbary Coast Divers
News and Events
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Next Dive Club Outing:
Bodega Bay - Sunday March 26th
Join us for a day of kayaking, crabbing mussel and mushroom picking on beautiful Bodega Bay. Overnighters can grab a campsite at one of the local areas ( i.e. Bodega Dunes) call Curt and Carol for more details or show up at the next meeting
California Department of Fish and Game,
Marine Region
Marine Management News
Lingcod, Rockfish Assessments Report Healthier Populations
The West Coast lingcod stock has been successfully rebuilt after being designated overfished by the federal government in 1999, the Pacific Fisheries Management Council (Council) has announced.
Lingcod are a favorite target of commercial and recreational fishermen. This voracious predator stakes out home territories in rocky reef areas, where it mainly preys on other fish.
Rebuilding so quickly is a great success story that shows how the Council's cutbacks on fishing can work, said Council Executive Director, Donald McIsaac. But even with the increased numbers, fishing for lingcod will still be restricted due to curtailments on fishing to allow rebuilding of canary and yelloweye rockfish, which live in similar habitat.
The lingcod stock was scheduled to be rebuilt by 2009, but the new assessment showed that the rebuilding target has already been reached and surpassed by 60 percent. Rebuilding the stock was accomplished without a complete closure of the lingcod or groundfish fisheries, sparing coastal communities whose economies depend to varying degrees on commercial and recreational fishing.
The status of other key overfished stocks has also significantly improved. The widow rockfish stock, which was declared overfished in 2001, increased in size by 25 percent between 2003 and 2005, and is now at 78 percent of its rebuilding target.
The darkblotched rockfish stock, which was also declared ?overfished? in 2001, increased by 25 percent between 2001 and 2005, and is now at 40 percent of its rebuilding target. Another hopeful sign for this species is that biologists predict three strong year-classes of juvenile darkblotched rockfish will join the adult population soon, increasing its breeding potential.
Assessments for other overfished stocks showed modest improvements, with a few showing little or no improvement.
The assessment for cowcod, which was declared overfished in 2000, showed modest improvement, while assessments for Pacific ocean perch and bocaccio (declared overfished in 1999) and canary rockfish (declared overfished in 2000) showed no significant change between 2003 and 2005. An assessment for yelloweye rockfish, which was declared overfished in 2002, showed the population to be in slightly worse shape
One
Fish, Two Fish: New Sensor Improves Fish Counts
Researchers at MIT have found a new way of looking beneath the ocean surface that could help definitively determine whether fish populations are shrinking.
A remote sensor system developed by Associate Professor Nicholas Makris of mechanical engineering, along with others at MIT, Northeastern University and the Naval Research Laboratory, allows scientists to track enormous fish populations, or shoals, as well as small schools, over a 10,000-square-kilometer area -- a vast improvement over conventional technology that can survey only about 100 square meters at a time...
"We're able to see for the first time what a large group of fish looks like," said Makris, who compared the dramatic improvement to the difference between seeing everything on a television screen and seeing only one pixel.
Current surveying methods depend on highly localized observations taken from slow-moving research vessels, which provide only a small amount of data about a large shoal, Makris said. "It would be like watching Casablanca and you're seeing one pixel moving across the screen, and that's all you get. You can't figure out what's going on, it's way too slow," he said.
Both the new and old methods rely on sonar, which locates objects by bouncing sound waves off of them. With the old technique, survey vessels send high-frequency sonar beams into the ocean, where they dissipate much like the light from a flashlight shining into a darkened room.
In contrast, the new system uses low-frequency sonar that can travel much greater distances and still return useful information with signals far less intense. This effectively "illuminates" vast areas of the ocean, about a million times larger than what could previously be studied. The images can be updated every minute, offering a chance to continuously monitor the shoals as they change in size and shape over time.
The new technology works best along the continental shelf, so the researchers focused their attention on the waters south of Long Island, New York. When they first started, they weren't looking for fish at all -- they wanted to see if their device could locate ancient riverbeds under the ocean floor. But when their reconnaissance images did not match the riverbeds, the researchers went back with a new approach, and determined that they were seeing fish -- tens of millions of fish.
This marks the first time scientists have been able to see the patterns formed by large fish populations. Makris found that fish often congregate in an hourglass pattern, also found among other animals, with a thin "bridge" connecting the two ends. The researchers also observed that the same shapes seen in a small scale appear on larger scales -- tens of meters vs. tens of kilometers -- displaying a fractal pattern.
[Friday Night Crew] back to crew! by Graham Charles
We had a fun first week back in force, with eight of us (including four youth!) to take care of the two new elephant seal weaners and the remaining sea lions. I just had to stare at this one (Peyton) to remember what they look like! (It didn't take me long to remember what they sound like!)
first weaner, Elephant Seal pup
our own Roy Coto, first on the scene
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updated 2/15/06