(KRON) — Over the weekend, two dead gray whales washed ashore in the Bay Area, the Marine Mammal Center confirmed to KRON4. Both whales washed ashore at various locations in Point Reyes National Seashore.

“To respond to two known gray whales on consecutive days, including one that our team has been actively monitoring for months in San Francisco Bay, is challenging and concerning to say the least,” said Dr. Pádraig Duignan, director of pathology at the Marine Mammal Center. “As sentinels for ocean health, gray whales face several human-caused threats including vessel strikes.” 

Officials with the Marine Mammal Center responded to a 39-foot adult male whale that washed ashore on North Beach on Tuesday. Officials said they had been closely monitoring this whale since it was first spotted in February in the San Francisco Bay. Its cause of death was most likely due to multiple boat strikes and malnutrition, officials said.

The whale was first sighted on Feb. 9 in good condition and again in March actively feeding, officials said. A necropsy on the whale revealed multiple rib and spinal fractures with evidence of attempted healing beneath a scar. This was most likely due to a strike to its back, which caused the whale to begin deteriorating. The team also discovered a skull fracture, hemorrhage and damage to the muscles around the neck, probably due to a boat strike which they said was probably the immediate cause of death.

Monday, the team responded to an adult male whale washed up in North Agate Beach. Officials said it’s believed, but not confirmed that this is the same whale spotted floating near Point Bonita Lighthouse. The cause of death in unconfirmed.

These are the third and fourth cases of dead whale washing ashore in the Bay Area this year. On March 25, a subadult male gray whale washed up on Bolinas Beach and on April 7, a juvenile male gray whale washed up at San Leandro Marina. The suspected cause of death for both of these prior cases is boat strikes.

Anyone who sees a whale is asked to report it on the Marine Mammal Center’s website.