Japanese whalers hunting the mammals in the northwestern Pacific caught a record-low 34 minke whales this Spring, the fisheries agency said Thursday, blaming bad weather.
The whaling, conducted in the name of "scientific research", took place from April 18 to June 3 and netted 17 male and 17 female minke. The catch is the lowest since Tokyo started the programme in 2003, the agency said.
"The weather was very bad this year, often with thick fog or very strong wind," said an agency official.
Japan's whale hunts, especially its annual Southern Ocean expedition, have long drawn criticism from activists and foreign governments, but Tokyo defends the practice saying eating whale is part of the country's culinary tradition.
It says whales are studied as part of a bid by Japan's whaling research institute to prove their populations can sustain commercial whaling.
Many of the whales this Spring were slightly smaller than last year, the official said.
Stomach samples from 22 of the creatures caught in Sendai Bay showed their diet was dominated by young sand eels, rather than mature sand eels as in the past, the group said, according to Kyodo News.
The whaling mission in the Southern Ocean this year also logged a "record low" catch of the mammals, with the government blaming "unforgivable sabotage" by activists.
Activists charge Tokyo's "research whaling" is cover for commercial whaling that is banned under an international agreement.
Explore further: Diabetes drug found in freshwater is a potential cause of intersex fish