Skip to main content

Record Warm Temps Causing Salmon Mortality Rates to Spike

Johathan Hayward/Canadian Press

The coastline along the Canadian province of British Columbia has been experiencing record warm temperatures.

The Canadian government says that's having a bad effect on Pacific salmon populations.

"We've seen the warmest winter temperatures [and] water temperatures ever observed in the northeast Pacific in 2014 and 2015," says Dr. Ian Perry, a research scientist with Fisheries and Oceans Canada (DFO). Perry, along with a panel of scientists from the DFO, says that the record warm temperatures have disrupted the fish's food supply.

In addition, predators have moved further in toward the coastline, feeding on young Pacific salmon.

The cause of the record warm water temperatures? The Blob, which was quite simply a blob of warm water in the Pacific Ocean until currents and cold winds from Alaska, which have been missing for several years, broke up the mass. In addition, the winter of 2015-16 saw a very strong El Nino weather pattern.

The warm weather is also affecting spawning patterns of the salmon. Because of the record warm, snowfall melts faster, spring temperatures have been above average and there has been less rainfall.

The result has been warmer rivers, which reduces spawning sites and makes the salmon more susceptible to pathogens. "The cumulative impact of all these stresses can actually lead to increased mortality," says Dr. David Patterson, a researcher with the DFO.

The DFO is going to monitor water temperatures and seasonally adjust Pacific salmon harvests to help maintain the species.


oembed rumble video here


you might also like

Record Warm Temps Causing Salmon Mortality Rates to Spike