Sea Shepherd says it needs more financial support to get all its ships in action against the Japanese whaling fleet next season.
The group confronts the Japanese whaling fleet every year in the Southern Ocean.
In February, a Court of Appeal judge in the United States likened Sea Shepherd to pirates and ordered the organisation to keep a distance from the fleet.
Sea Shepherd says this has dried up its flow of funds from the United States.
The anti whaling group says it will need all the support it can get to send all four of its ships south during the whaling season next summer.
The organisation says its protests are very expensive, with fuel alone costing $2 million.
Agriculture Minister Yoshimasa Hayashi says this season's whaling catch was a record low because of the attacks by Sea Shepherd.