Researchers call for emergency protections as 400 remaining animals fight for their lives.
Scientists suspect the die-off is fueled by declining food sources in the warming ocean waters near Alaska.
Nearly 100 whales are stuck in miserable holding pens after being captured for the aquarium trade.
A sperm whale found off the coast of Sardinia, Italy, was pregnant and carrying 49 pounds of plastic.
"I instinctively held my breath, assuming that it would dive down again and spit me out somewhere."
Marine mammal expert Regina Eisert said she thinks the whale wanted to share its dinner with her.
Nation's decision is bashed by environmentalists and Australia.
Rescuers in Indonesia also found 115 drinking cups and 25 plastic bags.
Noise from ships and boats are causing dolphins to make their calls less complex, according to a new study.
Tahlequah, whose newborn died on July 24, was spotted swimming without her calf's body on Saturday.
“I think it’s really easy to put human emotions on it, but personally I think it’s accurate. I think she is grieving,” a University of Washington scientist says.
Japan’s National Museum of Nature and Science said there is no record of this happening before in the country.
"They’ve got a fear of drowning, just like we have,” says expert.
Earlier deaths were caused by a ship strike and entanglement, while the latest death is still being examined.
"Right now, the sky is falling," warns a National Marine Fisheries Service scientist.
Kasatka was born in the wild, and had numerous descendants at SeaWorld.
Kyara, who was 3 months old, was the last orca born from the park's now-discontinued breeding program.