First Nations on Vancouver Island have agreed to forgo their traditional right to hunt grey whales for at least 25 years, in return for other benefits.

The Maa-nulth First Nations made a side agreement not to hunt the whales as part of the treaty they signed on the weekend in Victoria.

But Huu-ay-aht hereditary Chief Tom Mexsis Happynook, a long-time advocate of aboriginal whaling, said the treaty preserves the right to hunt whales in the future.

When the Makah band of Washington state shot and killed a whale in 1999, Happynook declared that First Nations on the west coast of Vancouver Island would also demand the right to resume a whale hunt as part of any treaty.

But when the Maa-nulth initialled the final agreement on the weekend, the word "whaling" did not appear in the text.

Happynook said the treaty recognizes an implicit right of the Maa-nulth to resume the whale hunt in the future, as part of the harvesting of wildlife, birds and fish for food, social or ceremonial purposes.

He said that under the side agreement the federal government will fund research on whales instead.

"Certainly there is some disappointment, but again we have to give some consideration to the whole treaty package," said the chief.

The treaty also gives the Maa-nulth 24,000 hectares of land, up to $300 million and a share of mineral and timber resources.