In a pinch, Crayfish in Alberta-Northern crayfish (Orconectes virilis) have been reported outside their native range in several locations in Alberta, including Nose Creek, the Bow River and most recently the Elbow River in the City of Calgary. The expansion of northern crayfish outside its native range in the Beaver River watershed in northeastern Alberta may be a combination of natural movement and deliberate or accidental transfer by humans.
Trout Unlimited Canada is aware that crayfish sightings have increased across southern Alberta and recent media attention has brought crayfish back into the limelight. Since the 1960’s there have been reports of crayfish across Alberta and in 2011 northern crayfish were documented outside of their native range across Alberta, Saskatchewan, Montana and North Dakota. In recent years, news outlets in Calgary have focused on crayfish discoveries by members of the public in Nose Creek and the Elbow River.
While Trout Unlimited Canada is aware of the existence of crayfish in the Calgary area, we not currently working to control or monitor the crayfish population. However, the spread and persistence of this non-native species serve as a reminder of how important it is to prevent the spread of aquatic invasive species. Once a new species is established in an ecosystem, it can be very difficult to control the potential impacts. Introduction of non-native species into new environments can alter the delicate balance of the ecosystem. For example, crayfish are bottom feeders that may compete for habitat and food with small-bodied, native fish including Longnose Dace and Spoonhead Sculpin. These small-bodied fish are an important piece of native biodiversity. The specific impact of non-native crayfish on trout is not known.
“Don’t let it loose”! Transport of live fish and crayfish is illegal. In fact, the penalty for illegally moving fish or in this instance crayfish into any water body aside from the one it was captured in can be up to $100,000, and/or a year in prison. In Alberta, crayfish can be harvested, but they must be killed before leaving the location where they were caught. Please check with your local public health authority for guidelines on consumption of crayfish and other fishes.
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