The magnificent and powerful steelhead that inhabit many of the legendary fishing rivers of British Columbia are swiftly moving ever closer to becoming an endangered species.
In last week’s column I talked about the plight of Thompson River steelhead specifically, and the fact they are under ever-increasing pressure due to a number of factors including global warming, changing ocean conditions, Interior fish habitat destruction and incidental catch by First Nation and commercial salmon fisheries along the Fraser River system.
I stated the situation was grim and their future uncertain.
I was surprised to learn afterwards how many people were, in fact, aware of the situation. I was also surprised to find out how little most people actually know about steelhead, other than that B.C. steelhead were once considered one of the most highly sought after of all sport fish.
Steelhead (Oncorhynchus mykiss) are rainbow trout that act more like salmon. In other words, they’re an anadromous form of rainbow trout that migrate to the ocean and return to the rivers where they were born to spawn. They also grow much larger than regular Interior resident rainbow trout. Unlike salmon, however, they do not necessarily die after spawning. Some return to the ocean while still others, under certain circumstances, do not actually go out to sea at all.
At one point, the Federal Department of Fisheries and Oceans (scientists) considered steelhead to be salmon. Now they say they are trout. Although according to the DFO website, they also say “steelhead are more closely related to Pacific salmon than to trout species in other parts of the world.”
Steelhead are similar appearance to rainbow trout, especially during the earlier stages of their life cycle. They can vary in colour depending on the amount of time they have spent in freshwater, as opposed to their marine environment. Mature adult steelhead can range in length from 50 to 85 centimetres and weight up to 25-plus kilograms.
In Canada, steelhead can be found in most of the larger British Columbia watersheds from the south coastal area through to northwestern part of the province.
There are two distinct runs of pre-spawn steelhead appropriately termed winter-run and summer-run steelhead. Summer-run fish begin to enter into freshwater as early as April and on through the warmer summer months. However, despite the differences in their migration timing, both winter- and summer-run fish typically spawn in the spring and early summer months.
Steelhead are able to spawn a number of times during their lives. Eggs are deposited into gravel redds located in shallow, fast-flowing waters. Newly hatched alevin remain in this gravel habitat until they emerge as fry. The fry move into deeper pools where they spend from one to three years before making their way to the ocean as smolts. Steelhead that have spawned and make their way back to the ocean are called kelts. They will stay in the ocean for up to a year before returning to spawn again.
The problem is that steelhead populations in our province are facing a great number of pressures and threats to their very existence. Steelhead numbers are in decline pretty well everywhere.