Researchers are trying to figure out why baby salmon sharks are washing up dead on central California beaches.
Almost a dozen dead sharks have been found in the past month, the Santa Cruz Sentinel said Friday.
Necropsies have shown that most of the salmon sharks had bacteria-induced brain infections at the time of their deaths, but researchers say they don't know what is causing the bacteria.
The newspaper said salmon sharks, common in the Gulf of Alaska, are rarely spotted alive in the waters off California's central coast. Dave Casper, a veterinarian with Long Marine Lab at the University of California-Santa Cruz, is asking local salmon fishermen to try to catch a live salmon shark so that he can study it.
"What is the common source for this bacteria, and do adults harbor the bacterium in their systems?" said Casper. "So far, all we've got is this encephalitis. There are more questions than answers."
Copyright 2007 by United Press International
Explore further: Longest ever tiger shark tracking reveals remarkable, bird-like migrations