Seismic blasting used in oil exploration can reach 250 decibels and be heard for miles. It can cause hearing loss, disorientation and disturb essential marine mammal behaviors such as feeding and breeding. Just over 300 Cook Inlet beluga whales are left after four more washed up dead in Cook Inlet in the past two weeks.
The current expanse of warm water stretches from Alaska to Southern California to Hawaii. It appears similar to conditions five years ago when the original “blob” was first taking shape, federal scientists said, although so far, the warmer-than-normal waters extend down only about 150 feet below the surface, rather than 600 feet five years ago.
“We were alarmed to find that diatoms were so negatively affected, with some species likely to have diminished silica production before the end of this century,” says Dr Petrou.
A listening station on the channel floor is able to capture whale calls as far away as 30 miles (48 kilometers), the Los Angeles Times reported Friday. That device is connected by cable to a buoy floating above that transmits data by satellite to scientists on shore.
So far, the cause of the die-offs remains a mystery, though theories include starvation from lack of food, or a disease that mimics chronic wasting disease. Teams of scientists are investigating what the casualties mean for the gray whale population as a whole. But some also fear that the deaths could be part of a larger trend as animals struggle to adapt to climate change. Said Ferguson: The “gray whales are just one piece” to the environmental puzzle.