More dolphins were found stranded on beaches east of Tokyo on Tuesday, a day after dozens of them had washed up in the same area.
Eight dolphins, of a species known as the melon-headed whale, were discovered at around 8 a.m. Tuesday along the shores of Isumi and Ichinomiya in Chiba Prefecture on the Pacific coast by local government officials and others. According to the officials, four of them were likely dead.
On Monday, a total of 33 dolphins, each approximately two meters long and likely to be adult, were found stranded over a distance of around 500 meters along the same shores. Three of them were dead.
Melon-headed whales are usually found in tropical to subtropical waters but head north for food in the spring.
"They may have weakened from swimming too close to the coast where the water is cold," Yukio Miyauchi, head of the Choshi Ocean Institute in Chiba Prefecture, said Monday.
The National Museum of Nature and Science will collect samples from the dead dolphins for analysis.
Local surfers and others returned the surviving animals to the ocean on Tuesday.
They made similar efforts Monday morning, but at that time many came back and they seemed to be struggling to breathe on the beach, according to an employee at a local surf shop who helped with the rescue.