In a sad postscript to news that salmon had returned to spawn in an urban Vancouver stream for the first time in decades, unidentified pollution has been spotted gushing into the creek that had been flowing crystal clear only a few days earlier.
Videographer Bruce Causier posted footage on YouTube showing the cloudy substance flowing into Still Creek on Saturday, with the spawning fish, known as chum salmon, swimming through the now-murky waters.
Causier, who regularly posts footage of urban wildlife in the Vancouver region, said that the substance was clearly a pollutant.
"To me, it looked like white paint, the way it was mixing in with the water," said Causier.
He watched the pale, cloudy substance flowing steadily into Still Creek for 45 minutes, then returned three hours later. It was still trickling out. The next two days, the creek was running clear again, but on Tuesday, to Causier's disappointment, a similar paint-like pollutant - this time brown - was flowing into the water.
He said that he suspected the pollution was coming from one of a number of local painting businesses adjacent to Still Creek, which runs under the Trans-Canada Highway a few blocks away.
Still Creek runs through heavily industrialised areas of east Vancouver and the satellite city of Burnaby, before disappearing somewhere under a car park.
The creek was once one of the most polluted waterways in British Columbia, but in recent years it has been the subject of an intensive clean-up. The news the salmon had returned to spawn in the creek for only the second time in more than half a century had been greeted with joy.