Skip to main content

Dig Imperial Beach

Dead Leopard Sharks among animals being found dead at Estuary

Apr 13, 2016 12:44PM ● By Paul Spear

Dead Leopard Sharks among animals being found dead at Estuary. Around 50 dead leopard sharks were seen on the banks of the Tijuana River in Imperial Beach.

Fox5 San Diego reports that Around 50 dead leopard sharks were seen on the banks of the Tijuana River in Imperial Beach that had been blocked by sand.

Brian Collins, 
U.S. Fish and Wildlife Service Refuge Manager,  said ""I've never seen this. The last time the river mouth closed was in 1983."

Think about the tide is like you breathing, The estuary is supposed to open to the Pacific Ocean at the river mouth. The tide helps cleans the water. With the river mouth closed dangerous runoff from Tijuana kept building up in the Estuary instead of escaping to the ocean.

Collins went on to say that Tijuana close down their sewage diverter pipe several days ago. So there's raw sewage in this system. "Seawater is going to return. It's freshwater mixed with whatever was in there," said Collins.

David Smith first reported the Tijuana River Mouth closed April 4th, 
“The Tijuana River Mouth Is Closed!” by David Smith.

The blockage created stagnant pools that ultimately killed the sharks and other wildlife, the newspaper reported.  Birds and other scavengers were seen feeding off the dead sharks.  Imperial Beach Mayor Serge Dedina said he counted around 50 dead sharks along the shore.

Brian Collins, manager of the San Diego Bay and Tijuana Slough national refuges is very concerned about the feeding area. Many of the birds on the "Endangered Species List" depend on clams that are buried in the mud to feed off of. Since the closure of the river mouth many of those clams have been covered by polluted water and it is not known how they have survived being covered up by polluted water and if they do survive will they still be good for the birds to feed off of. Only time will tell for sure.

On April 11th we reported that Tijuana River Mouth is open again and flowing smoothly to Ocean

Brian Collins was encouraged that we will be having some high tides the next couple of weeks and he is hopeful that will help clean up some of the ecosystem that has become so heavily polluted.

You can see Fox5's article here: Joe Little reported on the situation as well. You can find his article at:

We used pieces of both TV reports above to obtain so of our information as well as speaking with Brian Collins directly.

Brian Collins is Refuge Manager for the San Diego Bay and Tijuana Slough National Wildlife Refuges.

Like what you're reading? Subscribe to Dig Imperial Beach's free newsletter to catch every headline