REDWOOD CITY (KCBS) - Researchers said Friday they are baffled why a dozen leopard sharks died in tide pools and sloughs off Redwood City over the last several days.
Canals that regulate tide flow may be preventing the sharks, which usually grow about five feet long, from escaping some kind of toxic discharge or other manmade pollution source, said Sean Van Sommeran with the Pelagic Shark Research Foundation in Santa Cruz.
KCBS' Melissa Culross Reports:
"We're mapping and photographing and making contact with the management for the nearby facilities that control the flow of water through those manmade canals," he said.
Leopard sharks are a non-aggressive species that tend to ignore humans and can live up to 40 years. Van Sommeran said they are very common up and down the California coast.
"They're a very important feature of the Monterey and San Francisco Bay areas, kind of a signature species of California as well," he said.
Shark die-offs are not unusual, although Van Sommeran said they are becoming more common. The first calls on this one came Monday south of Foster City.
So far, this die-off appears less severe than more widespread incidents in 2006 and 2007. Researchers cautioned that other creatures succumbing to the unidentified toxin or pollutant could be floundering further from land.
State and federal wildlife officials are helping with the investigation.
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