BC’s Unknown Sports Fish

Anglers in BC have a wide selection of freshwater game fish to pursue – some that are widespread and well known, while others, because of low numbers or restricted ranges, are less known, and there is one species that is actually unknown. This stranger is the inconnu, and it’s literally unknown because that is the translation of inconnu from French. This species occurs in the large rivers and lakes of far northern Canada and Siberia, but in BC they are found only in two locations: Teslin Lake and the Yukon River system in northcentral BC, and the Liard River drainage in the northeast corner of the province, north of Fort Nelson. This remote and restricted range means that few BC anglers encounter them. In fact, inconnu does not even appear on some lists of BC freshwater fish, and there is not much known about their life histories here. This truly is our province’s unknown sports fish.

The scientific name for inconnu, Stenodus leucichthys, translates from Greek as “narrow tooth whitefish” and other common names include coney, connie and sheefish. These fish have a long, tapered, silvery body covered with very large scales, with a silver-green coloured back and silver-white belly. Their head is large and broad, with the lower jaw jutting out past the upper jaw, similar to the tarpon of tropical waters. The tip of the lower jaw is armed with rows of small teeth. Their large fins have dark tips, and the tail fin is deeply forked.

Inconnu are related to many of the game fish we do know. The salmon family (Salmonidae) includes three subfamilies: Salmoninae (salmons, trouts and chars), Thymalinae (graylings) and Coregoninae (whitefishes). Inconnus are the largest and fastest growing of the whitefishes. The North American record sport-caught inconnu is 24 kilograms (53 pounds), but adults typically weigh less than seven kilograms. However, that is still a large fish, and they get to that size by eating almost anything. Depending on age and habitat, the menu includes aquatic insects, invertebrates and any fish of any species that can fit into their mouth. Some inconnus are anadromous and are often the larger specimens because those that live in the river estuaries or go to sea find more and larger prey items. Others are residents in large northern rivers like the Yukon and the Mackenzie, or in the lakes associated with these rivers. Tagged inconnu have been recaptured after migrations of 1,800 kilometres in the Mackenzie River system.

Inconnu spawning season is early autumn and they select sites with clean gravel in clear headwater streams, in water that may be only a few degrees above freezing. The frequency of spawning is still a question; they likely don’t spawn every year, and some possibly as seldom as every four years. A spawning female will carry many tens, or even hundreds of thousands of eggs, comprising as much as 30 per cent of her body weight. This fecundity compensates in part for the very long time to reach sexual maturity, which may be seven, eight or even 10 years. The young inconnu likely remain in the natal streams for a few years before migrating to the bigger rivers, lakes or to the ocean, but apparently some may remain in the home stream to grow to adulthood. Inconnu may live to see a 22nd birthday; however, longevity estimates in various sources vary from 12 years to 40 years. There is definitely more to know about this species.

In parts of Alaska, Yukon and Northwest Territories, inconnu is an important food fish and there are commercial fisheries, as well as sustenance and sport fisheries. For people on a diet, though, this fish may not be a good choice. Inconnu are considered to be very oily, with several times the calorie content per serving compared to lean fish like northern pike or cod. Some people find the flesh to be soft, almost mushy, as well as oily. However, the table quality of inconnu flesh might depend on the time of year, spawning condition and the method of cooking. In some reports, the authors raved about the flavour of inconnu, while others were less impressed. So, right from the egg in the gravel to the fillet on the plate, there is much more to learn about inconnu, this “unknown” fish of northern BC.