HERMOSA BEACH (CBSLA) – The carcass of a gray whale was discovered off Hermosa Beach Monday, while a live gray whale was also spotted in Marina del Rey on the same day.

The carcass of the 20-foot gray whale was found floating on the south end of Hermosa Beach, about 500 yards offshore, according to the Los Angeles County Fire Department Lifeguard Division.

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A young gray whale is spotted in a channel in Marina del Ray, Calif. March 18, 2019. (Credit: Vicki Kysella/Instagram)

The National Marine Fishery Service (NMFS) was working with lifeguards to monitor its position.

Meanwhile, a young gray whale was also spotted Monday swimming in the main channel of Marina del Rey, lifeguards reported. NMFS was also keeping track of that whale as well.

Boaters were being asked to navigate the area with caution.

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This comes after two gray whale carcasses were also found in San Francisco Bay last week, an unusual occurrence.

The marine mammals are in the midst of their annual spring migration from Baja California all the way north to Alaska.

Dr. Padraig Duignan, chief pathologist at the Marine Mammal Center in Sausalito, told CBS San Francisco that the whale deaths in the bay were concerning to biologists because they could be a sign that global warming in Alaska is potentially endangering the whales and changing their living conditions.

“It has to be a concern for us,” Duignan told CBS San Francisco. “It has to be an area of warning that perhaps something is changing drastically in their habitat in the north, in the Arctic waters, that they’re not getting enough food.”

Anyone with questions can contact the nonprofit group Marine Animal Rescue at 800-39-WHALE.

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