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By laws | Dams | Fish | Plants | Pollution | Watershed | Water Treatment | Wetlands


By Alysia, Quintin and Brandon T.

Fish have an important role in rivers. They are known as the indicator species. This means that if there are many fish in a river that river is healthy. However, if there are too few fish in the river it means the river is dirty or polluted. The population of fish is important. There should be a particular number of fish in a river depending on the size of the river. If there are too many fish in the Bow River the food will go too fast and the fish will decrease in numbers. If there is too few fish and there are too many plants they will fight for oxygen.

Fish have a varied life span. Fish can live for a few years or many years depending on the food supply and condition of the water. Fish can live from 1week to 100 years. Fish have many predators such as bears, fishermen and a lot more. The life stages of fish are egg, eyed egg, alevin, fry, young fish and adult.

There are many types of fish found in the Bow River. The most common fish you would see is the Rainbow Trout you would also see Brown Trout. Besides the Rainbow Trout and Brown Trout there is also Brook Tout, Cutthroat Tout, Dolly Varden, Golden Trout, Lake Trout and Mountain Whitefish.

On the Bow River one main tourist attraction is fly-fishing. The Bow River downstream from Calgary has larger trout size than virtually any other stream in North America. The Bow continues to provide fly fishers a lot of rainbow and brown trout between 20 and 24 inches in length. The Bow River has 500 to 600 Brown trout per kilometer and about 1200 rainbow trout per kilometer. Brown trout in the Bow attract fly fishers from all around the world.

Fishing in the Bow River is best from April to May and from September to October
The catis fly hatches at those times and fish love catis fly. This makes the fish really active while competing to eat them. This gives the advantage to anglers, or fly fishers. They can make a lure that looks like that type of insect, and the fish would easily bite at it. Fly-fishing is a type of fishing that instead of normal casting the rod is flung to make the lure look like an actual fly.

Over fishing by people is a threat to the fish population. This is a problem because if everyone were to do this fish would not have time to reproduce. There is a catch limit for fishing. A person can only catch a certain amount of fish. The catch limit is different for different kind of fish. For example the rainbow trout has a catch limit of 5, but the artic grayling has a limit of 2. You are not allowed to catch any Bull Trout because it is an endangered species. In order to catch any fish you have to have a license, you can buy these at the places where you buy fishing gear. The licenses are supplied by Alberta Fish and Wildlife, who also monitor the fish population to make sure it is healthy.

There are many threats to the fish in the Bow River. Chemicals in the storm drain system can make its way into the Bow River and pollute it. People littering and putting garbage in the river are other examples of pollution. Drought is also a threat to the fish population. If the weather is too hot the water level in the river will be low. This can affect the fish by stopping them from where they need to go for spawning. The fishes’ ecosystem would also be threatened by the drought making it difficult for the fish to get their food.