Hot temperatures in Alaska cause king salmon to die

Thursday, August 8, 2013, 12:15 PM -

Can the warm weather be to blame for the deaths of over a thousand king salmon in Alaska? After having record highs for a number of days this week and having an overall warm summer, this seems to be the probable cause. 

It was just three weeks ago where about 1,100 hatchery king salmon died when being returned to a lake to spawn. Officials suspect that the hot temperatures increased the temperature of the water, which ultimately led to the fish dying. 

And the same thing also happened in June with the trout. Hundreds of grayling and rainbow trout died after being placed in Fairbanks Lake.

Alaskan Grayling Trout

With the National Weather Service reporting temperatures reaching the high twenties and low thirties this past week, more fish may continue to die. But it hasn’t just been this past week that Alaska has had very warm weather. Fairbanks also set a new record on August 1, beating the record for the total number of days with temperatures over 80 (about 26 degrees Celsius). The National Weather Service reported them having 31 days with high temperatures, beating the previous record of 30 days set in 2004. Numerous places, such as Anchorage, Valdez, McGrath, and King Salmon, have also beat daily record temperatures. 

This hot and dry weather has also caused numerous wildfires in the state. Both state and federal wildfire managers say that over a million acres across Alaska have been charred due to these fires. This is over fifty thousand more acres than the annual average. 

So with all of this heat, it is no wonder that the number of fish are diminishing. Doug Fleming, a biologist for the Alaska Department of Fish and Game, has been monitoring the water temperatures following the warm weather in late July and the death of the king salmon. He believes the water temperature is reaching dangerous levels. Although, the hot water temperature is not only to blame. Fleming suspects a combination of a number of things to have caused the die-off. This includes low oxygen levels in the water, lower tides that did not bring in enough cool water from the ocean, and a large number of fish becoming trapped at Blind Slough. 

Unfortunately, this is not an uncommon occurrence. In the last 35 years, there have been six occurrences where over 500 fish have died. 

But there may be some relief in sight. For the rest of the week the forecast for most areas calls for temperatures to stay around the low twenties. This may not seem like a significant drop in temperature but for now it will have to do. Hopefully this will be enough of a decrease that no more fish die.