The rainbow trout(Oncorhynchus mykiss), aka redband trout, is a species of Pacific salmon(1989) native to tributaries of the Pacific Ocean in Asia and North America. Fish which have gone to sea (including those returning for spawning) are known as Steelhead, or ocean trout (Australia). The species has been introduced for food or sport to at least 45 countries, and every continent except Antarctica. In some of these locations, such as Australia, they have had very serious negative impacts on upland native fish species.
The species was originally named byJohann Julius Walbaumin 1792. In 1855, W. P. Gibbons found a population and named it Salmo iridia, however this name became deprecated once it was determined that this was a population of the already named species. Rainbow trout are unusual in that although they can spend their entire life in fresh water, they are capable of migrating to sea water when conditions are right, though they must return to fresh water to breed.The freshwater form is called “rainbow trout” or “redband trout”, based on the broad red band along their sides. After going to sea, their color changes, including loss of the red band, and they are called “steelhead”.
They occur in well oxygenated lakes and streams where the temperature doesn’t rise above 12°C in summer. Rainbows and steelhead have small black spots along their back, dorsal fin and caudal fin. Behind the dorsal fin, rainbows have an adipose finthat is commonly clipped from fish raised in a hatchery. Clipping the adipose fin helps distinguish hatchery fish from wild fish when they are taken by anglers. This allows enforcement of regulations to protect wild rainbows. Rainbows have a red or pink streak that runs from the gill cover to the caudal fin, inspiring their name. The color of a rainbow’s back varies from blue or green to a yellow-green or brown. Steelhead usually lack the pink stripe and have chrome-colored sides. Rainbows are distinguished from their cousins, the cutthroat trout(Oncorhynchus clarki) by their short maxilla, which reaches to, but not past the rear margin of the eye. Rainbow trout also lack hyoid teeth, a feature present in cutthroat trout.Rainbows range from 12 to 36 inches in length.
Steelheads grow longer, ranging from 50 to 100 cm (20 to 40 inches) in length. Steelhead range in weight from 2.5 kg to 10 kg. The world record rainbow was a 42 pound specimen caught near Bell Island, AK.Here in Calgary Alberta, there are no Steelhead present as we have no ocean. On the Bow River specifically, we support a large population of Rainbow Trout which can grow to lengths of over 30 inches long.
Rainbow Trout spawn here in the spring where they make their way down stream to the Highwood River in early March. Once the ice on the Highwood River has thawed, the Bow River Rainbow Troutmake their journey up to spawn in the Highwood River and it’s many tributaries. You can fish for the Rainbow Trout at the staging point where the mouth of the Highwood River meets the Bow River. If you are looking for great Rainbow Trout fishing than you need not look any further than the Bow River. If you would like a guided trip to fish for these “Bow River bullits” as they are called here, click the guided fishing trip page at the top of the Blog, or click here.
