Two gray whales were found dead under separate circumstances in San Francisco Bay waters this week, according to the Marine Mammal Center in Sausalito.
The first carcass was reported Sunday floating between Tiburon and Angel Island and eventually washed ashore at Belvedere Cove, the center said. The whale had a significant lack of blubber and body fat, and the cause of death was determined to be severe malnutrition.
"It makes us concerned food limitations made it hard for her to thrive, so certainly a concern in relation to ocean health and climate issues," Dr. Cara Field said.
The second whale carcass was found Monday floating near the Bay Bridge, the center said. Its cause of death has not yet been determined, but scientists fear it could be from a ship strike as it did not show signs of malnutrition.
Both of the year-old, 23-foot females were towed to Angel Island on Monday afternoon for marine pathologists to perform necropsies, the center said.
Experts have noticed changes in migratory behavior in gray whales entering the bay in the late winter and early spring months, the center said. Typically, one or two gray whales will temporarily pass underneath the Golden Gate Bridge during this time, but last week alone, experts counted five entering the bay.
"The number of gray whales entering the San Francisco Bay this year has been abnormally high, and they’re staying much longer than in years past,” Bill Keener of the Golden Gate Cetacean Research said in a statement. "There’s likely a few factors at play here including food source availability and a relatively sheltered habitat for juvenile whales that are in weaker body condition."
For those who wish to try to get a glimpse of the the remaining three gray whales out on the bay, experts urge them to keep their distance.