Ottawa has been asked to support a full closure of this summer's chinook salmon harvest until there's enough fish to meet spawning goals.

The letter requesting the support was sent Tuesday by the Yukon Salmon Sub-Committee to federal minister Gail Shea of the Department of Fisheries and Oceans.

The closure includes supporting a zero harvest by Yukon First Nations, for the first time ever.

Salmon Sub-Committee chair Pauline Frost said this morning the closure is supported by the Yukon's First Nations.

In her letter, Frost points out preseason predictions by authorities on both sides of the border are anticipating another poor return of chinook this summer, perhaps even the worst on record.

She said today information coming out of Alaska so far indicates another below-average year.

In five of the last seven years, fewer than the desired spawning target of 42,500 chinook have even crossed into the Yukon, according to the sonar counts near the Yukon-Alaska border, says the letter to Shea.

The letter says the closure of the First Nation fishery is intended to achieve the 42,500 objective, after which the potential for a harvest by the aboriginal food fishery will be revisited.

Last summer, the sonar count at Eagle, Alaska indicates just over 30,000 chinook crossed into the Yukon, or 12,500 short of the minimum spawning target.

The annual chinook salmon run has been declining for years, and scientists readily admit they don't know exactly why.

A full closure of the chinook fishery in Alaska has been implemented this year, including a closure of the subsistence fishery for the first time.

Under law established by the Supreme Court of Canada, First Nations cannot be restricted in their traditional practice of harvesting meat or fish unless there is a conservation concern or issues related to public health and safety.

Frost said the salmon sub-committee will host a weekly teleconference with the Yukon First Nations during the run.

Should it exceed 42,500, though it's not expected to, they'll discuss options for a possible harvest, she said.

Frost said the sub-committee has been assured by Alaska that it would not object to an aboriginal food fishery in the Yukon as long as the territory fulfills its international treaty commitment of meeting the minimum escapement goal.

Given the abnormally early start to this year's chinook migration, the sub-committee would expect to hear back from the federal minister fairly soon, she said.

Frost was on her way to Dawson today to host a public meeting this evening.

Fewer than 20 years ago, it wasn't uncommon for Dawson's commercial fishery to harvest more than 10,000 chinook annually, in addition to aboriginal food harvest of 8,000-plus.

Back in the day, it was commonplace for Alaska's commercial boats to take in excess of 100,000 chinook or more in a season, in addition to the subsistence fishery that would harvest nearly 50,000 annually.

There has been no commercial fishing on either side of the border to speak for several years.

Yukon First Nations in recent years have been critical of Alaska's subsistence fishery.

They've voiced their objection to the fishery continuing to take tens of thousands of chinook annually – approximately half of which are of Yukon origin – while the run was obviously in trouble.