Calif. - Salmon Declines & Squid Increases

The squid have not been found to be eating the salmon - but the conditions that are reducing salmon and the conditions where squid are increasing seem linked. It could also be that the squid are eating the food sources of the salmon.

The number of chinook salmon returning to California's Central Valley has reached a near-record low, pointing to an "unprecedented collapse" that could lead to severe restrictions on West Coast salmon fishing this year, according to federal fishery regulators.

The sharp drop in chinook or "king" salmon returning from the Pacific Ocean to spawn in the Sacramento River and its tributaries this past fall is part of broader decline in wild salmon runs in rivers across the West.

The population dropped more than 88 percent from its all-time high five years ago, according to an internal memo sent to members of the Pacific Fishery Management Council and obtained by The Associated Press.

Regulators are still trying to understand the reasons for the shrinking number of spawners; some scientists believe it could be related to changes in the ocean linked to global warming.

Only about 90,000 returning adult salmon were counted in the Central Valley in 2007, the second lowest number on record, the memo said. The population was at 277,000 in 2006 and 804,000 five years ago.

Fishermen face new, increasing threat from jumbo squid

Marine biologists have known for years that 100-pound squid have quietly made their way from the tropical regions of the Pacific to the cooler reaches of California.

With 10 arms, a sharp beak and a mythic reputation for hunting in packs and attacking everything from scuba divers to each other, the Humboldt squid, also known as the jumbo squid, is now a common sight for fishermen and a current fascination of ocean-gazers.

But how much of a nuisance the little-understood cephalopod could become has only recently become clear.

Researchers in Santa Cruz have found that the squid's favorite foods are some of the most popular catches of fishermen in the region -- meaning competition, and perhaps another threat to an industry that has long struggled in the Monterey Bay.

"It looks like the squid have eaten a lot of the fish that are commercially important," said John Field, a fishery biologist with the National Oceanic and Atmospheric Administration...

Zeidberg, who spends time at Hopkins Marine Station in Pacific Grove, has found that the squid population in California, now likely in the hundreds of thousands, has been on the rise since 2002. While the squid have come to California before, never have they been seen in these numbers and for this long.

Zeidberg, Field and others are still trying to explain why the squid's population is growing outside of its native tropics, a trend that has played out in the Southern Hemisphere as well. Some say it's a lack of predators. Others say it's how rising ocean temperatures have created new hunting opportunities for the squid. But there's little consensus.