A sickened leopard shark struggles in the San Francisco Bay on April 21, 2017.

Media: Pelagic Shark Research Foundation

For seven weeks straight, hundreds of sharks have been washing up dead on the shores of the San Francisco Bay.

Sean Van Sommeran, executive director and founder of the Pelagic Shark Research Foundation, says he’s been getting calls daily since March of reported sharks washed up along the waterways of San Mateo County, Alameda and even Lake Merritt.

“We cant actually keep up with the volume of calls we get on a day-to-day basis,” Van Sommeran said.

Several types of marine life have been turning up dead, including rays and large fish like halibut. But primarily, Van Sommeran has been seeing hundreds of leopard sharks washing up. He estimates the number of dead and dying sharks in the bay could be in the thousands.

“This is just the tip of the iceberg,” Van Sommeran told SFGATE. “We’re only seeing a fraction of the actual losses.”

Van Sommeran’s years of research have led him to believe the explanation for the recent spike in stranded sharks can be found in Redwood City. “That appears to be the epicenter of all these incidents,” he said.

The researcher explained it all comes down to the city’s use of tide gates in residential areas near inland waterways. To keep from flooding during the rainy season, Redwood City closes its tide gates during low tide. That way, when there are heavy rains, the extra precipitation doesn’t combine with high tides to flood homes along the water. …..More Here