Canada airlifting thousands of trapped migrating salmon upstream

Migrating salmon, which were caught in a net, are held during a tagging operation near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS.

TORONTO (Reuters) - Canada is airlifting thousands of salmon upstream after a rockslide blocked the path of the migrating fish, triggering concerns of a permanent loss of fish populations, government officials said.

The Big Bar rockslide, which officials believe occurred in late October or early November 2018, is located in the Fraser River just north of the town of Lillooet in northern British Columbia. Because of the remoteness of the location, the slide was not discovered until late June 2019.

A crew catches migrating salmon in a net during a tagging operation near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Picture taken July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

It created a waterfall which is preventing millions of chinook, steelhead, coho and sockeye salmon from swimming upstream to their habitual spawning grounds.

The provincial and federal governments are now working with local First Nations communities to move the salmon manually upstream, by creating holding ponds that will allow them to transport the fish via helicopter to a site further upstream.

"Collaborative efforts like this one, with all partners ... are crucial and will give the best chance of survival to these stocks," Jonathan Wilkinson, federal minister of fisheries and oceans, said in a statement on Friday.

A helicopter flies past the site of the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Picture taken July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Other fish movement options being enacted are physically moving rocks from the slide to create a series of natural pools for the fish to rest in, and a fish transportation system of flexible pressurized tubes, the provincial government has said.

The fish will be monitored on their journey, including through blood samples taken to assess their energy reserves once they have passed the obstruction.

(This story refiles to correct spelling of sockeye in paragraph three)

A trench to be used as a holding pond for migrating salmon is constructed, as an airlift is planned for the fish near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 20, 2019. Picture taken July 20, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS.

(Reporting by Moira Warburton; Editing by Tom Brown)

A helicopter delivers equipment for a trench to be used as a holding pond for migrating salmon, as an airlift is planned for them near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 20, 2019. Picture taken July 20, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Migrating salmon, which were caught in a net, are held during a tagging operation near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Picture taken July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS.

Water flows downstream past the site of the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 20, 2019. Picture taken July 20, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS.

A crew catches migrating salmon in a net during a tagging operation near the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Picture taken July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Water flows downstream past the site of the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 2, 2019. Picture taken July 2, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Part of the crew tackling the Big Bar landslide uses an instrument on a bluff overlooking the Fraser River northwest of Clinton, British Columbia, Canada July 18, 2019. Picture taken July 18, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

A member of a climbing crew, working on a bluff over the site of the Big Bar landslide on the Fraser River, speaks with Canadian Coast Guard officers northwest of Clinton, British Columbia, Canada July 15, 2019. Picture taken July 15, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Crews, working on a bluff over the site of the Big Bar landslide on the Fraser River, speak with a Canadian Coast Guard officer northwest of Clinton, British Columbia, Canada July 14, 2019. Picture taken July 14, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Crews gather on a bluff over the site of the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 14, 2019. Picture taken July 14, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

Water flows downstream past the site of the Big Bar landslide on the Fraser River northwest of Clinton, British Columbia, Canada July 14, 2019. Picture taken July 14, 2019. Courtesy of Incident Command Post (ICP)/Handout via REUTERS. THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.