DFO Science Central and Arctic Region Stock Status Report D5-04 (1998) A BEAUFORT SEA d m / Tuktoyaktuk u 1 n 2 Peninsula d s e n Mackenzie { 3 Delta 4 Horseshoe G 5 Bend u R l f 6 Inu vialuit l e a e c k P A e n c z t i i e c R Mackenzie River Inconnu e G w ich'in d 7 8 Nunavut R The i Sahtu v e Ramparts Background r 9 G ea t B ea R Great Bear Lake The inconnu (also called coney or sruh), Stenodus 10 M 11 leucichthys nelma (Pallas), is a long silvery fish with a c large scales, a wide mouth extending back to the k e n posterior edge of the pupil and a projecting lower z i e North jaw (McPhail and Lindsey 1970). It is a member of Deh Cho Slave the family Salmonidae, subfamily Coregoninae or i v e whitefishes (Nelson 1976). Adult inconnu may grow 12 R r d to lengths in excess of 1 meter. 1 Shingle Point a 2 Tuktoyaktuk i 3 Aklavik 13 4 Inuvik 5 Fort McPherson Great Slave Inconnu are most abundant in large silty northern 6 Tsiigehtchic 7 Fort Good Hope Lake 8 Colville La ke 14 S rivers and associated lakes. The adults are l 9 Norman Wells a South 10 Tulit'a e voracious predators feeding mainly on small fishes Slave 11 Delin e R 12 Fort Simpson i v (McPhail and Lindsey 1970). Anadromous inconnu 13 Fort Providence e 14 Hay River 15 r are highly migratory, often travelling in excess of 15 Fort Smith 0 300 km 1000 km upstream to spawning areas in the Mackenzie mainstream Mackenzie River and its major Shingle Bay tributaries. Spawning occurs just prior to freeze up Point in early October. After spawning, inconnu migrate l Tuktoyaktuk e to feeding and overwintering areas in the lower n e l n n MACKENZIE o a n k h l reaches of the Mackenzie River, Tuktoyaktuk u T a e C h Y W n t C s DELTA n Harbour, and west along the Beaufort Sea coast to N e a h Shingle Point. Some stocks of inconnu in the W C s e a Mackenzie River are non-anadromous. Aklavik dl E id M Inu vik Aboriginal fisheries along the Mackenzie River have harvested inconnu for centuries. It is one of several species caught by the mixed-species subsistence fisheries that occur along the Mackenzie River and by the smaller commercial fishery in the Mackenzie Delta. The Mackenzie River flows through four land Figure 1. Map of the Mackenzie River, claims areas: Deh Cho, Sahtu, Gwich’in and Mackenzie Delta, Great Slave and Great Inuvialuit ( Figure 1). This report was prepared as input for the Integrated Fisheries Management Plan Bear Lakes showing the Inuvialuit, Gwich’in, being developed by the Department of Fisheries and Sahtu and Deh Cho Land Claim Areas. Oceans, Fisheries Joint Management Committee and Gwich’in and Sahtu Renewable Resource Boards. September 1998 Central and Arctic Region Mackenzie River Inconnu The Fishery 7000 6000 The food fisheries along the Mackenzie 5000 River and its tributaries are sporadic in 4000 nature, therefore the harvest statistics 3000 presented in this section do not represent 2000 1000 trends in inconnu abundance. Variation in the Number of Fish catch reflects the considerable year-to-year 0 1995 1996 1997 variation in fishing effort which is Year characteristic of both the food and commercial fisheries. Aklavik Fort McPherson Inuvik Between 1988 and 1997, Inuvialuit food Tsiigehtchic fisheries (Figure 2) harvested, on average, All Gwich'in Communities Figure 3. Inconnu harvested by the 9000 8000 Gwich'in food fishery. 7000 6000 5000 Estimates of weight harvested are based on 4000 the assumption that the average harvested 3000 weight of an inconnu is 2.5 kg, calculated 2000 Number of Fish 1000 from length-weight equations and mean 0 lengths presented by Howland et al. 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 (unpublished (b)) for an exploratory fishery Year conducted in the Horseshoe Bend area with Aklavik 139 mm mesh gillnets. Calculated weights Inuvik are probably underestimates because Tuktoyaktuk Horseshoe Bend is in the lower reaches of All Inuvialuit Communities the Mackenzie River and the exploratory fishery was conducted at a time when many Figure 2. Inconnu harvested by the of the larger adult spawning inconnu had Inuvialuit food fishery. already passed through as they moved further upstream to spawning areas. approximately 5150 inconnu per year (12,875 kg). Gwich’in food fishery harvests Harvests in the Gwich’in Settlement Area (Figure 3) averaged approximately 4,225 peak in early July, corresponding to the inconnu per year (10,560 kg) between 1995 harvest of current-year spawning adults, and 1997. Harvest levels in the Sahtu and captured while swimming upstream. Deh Cho Land Claim Areas are largely Harvests peak again in October, unknown. Reported catches are corresponding to the harvest of adult post- underestimates because they do not account spawning migrants moving downstream for fishers who were not interviewed and (Figure 4). Harvests in the Inuvialuit inconnu that were enumerated as “fish Settlement Region peak during the same species” when fishers could not remember months as observed in the Gwich’in what species they had caught. Settlement Area but the trend is not as pronounced. There are considerable 2 Central and Arctic Region Mackenzie River Inconnu differences in monthly harvest patterns for Mackenzie River inconnu but these harvests both of these areas among years and among are extremely low. communities. 2000 10000 8000 1500 6000 1000 4000 500 2000 0 0 Number of Fish Jul Jan Sep Mar Nov May (Canadian Dollars) Harvest (kg) and Value Aklavik 1988/89 1989/90 1990/91 1991/92 1992/93 1993/94 1994/95 1995/96 1996/97 Ft. McPherson Fiscal Year Inuvik Harvest (kg) Tsiigehtchic Landed Value in Canadian Dollars Figure 4. Monthly sums of inconnu Figure 5. Inconnu harvests of Inuvialuit and harvested by the Gwich’in food fishery for Gwich'in commercial and exploratory the years 1995 to 1997. fisheries. The vulnerability of Mackenzie River All inconnu harvested by the Gwich’in food inconnu to food and commercial fishing fishery are not necessarily harvested within cannot be characterized by a single age, the Gwich’in Settlement Area. The same length or stage of maturity. The food fishery holds true for Inuvialuit subsistence harvests. harvests fish from a number of different For example, the harvests of Gwich’in fishers stocks and life history stages within each in the Inuvialuit Settlement Region are stock. Each stock may have unique age and reported only in the Gwich’in subsistence size distributions and rates of maturity. harvest monitoring reports. Future harvest Furthermore, fishing occurs at various monitoring data will be more useful for locations and uses a variety of mesh sizes. management purposes if harvest location can also be reported. Location data are available The Horseshoe Bend exploratory fishery for Gwich’in subsistence harvests and it used 139 mm mesh gillnets , the most would be very useful for management common size of gillnet used by the food and purposes to analyze and publish these data. commercial fisheries. Inconnu, taken by this fishery, become fully vulnerable to the Commercial and exploratory fishing effort is fishery at lengths of approximately 600 to low and restricted to the management areas 700 mm and at ages of 9 to 14 years of the Mackenzie Delta and Horseshoe (Howland et al. unpublished (b)). These Bend. Commercial fisheries have, on vulnerability statistics may be biased because average, harvested approximately 2,500 kg many of the larger adult spawners had likely annually for the period between 1988 to passed through Horseshoe Bend prior to the 1997 (Figure 5). Sport fishers and resident time at which the fishery occurred. non-aboriginal fishers also harvest Therefore, inconnu likely become fully vulnerable to many of the other fisheries 3 Central and Arctic Region Mackenzie River Inconnu along the Mackenzie River at fork lengths km complex of channels, islands, lakes and greater than 600 to 700 mm and ages greater muskeg (Stein et al. 1973). than 9 to 14 years. With the limited scientific and traditional Female inconnu appear to be more knowledge on Mackenzie River inconnu vulnerable to harvest than are males. The stock structure and migration, general ratio of female to male inconnu harvested by conclusions can be drawn with caution. It is the Horseshoe Bend fishery was 3 to 1 interesting to note that Gwich’in traditional (Howland et al. unpublished (b)). Adult knowledge on migration, stock structure and inconnu harvested by the fisheries are not general inconnu biology (Gwich’in Renewable necessarily current-year spawners because Resource Board 1997) is consistent with the inconnu may not spawn every year after they scientific knowledge available on this reach maturity. species. Views of the fishers. Fishers from the Sahtu Stock delineation (Taptuna and Low 1995) and the Gwich’in (Gwich’in Renewable Resource Board 1997, Inconnu inhabiting the lower Mackenzie Simon 1998) Settlement Areas generally River appear to be made up of four stocks. indicated that inconnu abundance has Inconnu that spawn in the Peel River changed little during their lifetimes as fishers. (designated as D5-01) are anadromous and They report no signs that inconnu are smaller appear to overwinter in the western portion in size or have been depleted by the fisheries of the Mackenzie Delta and further west along the Mackenzie River or have changed along the Beaufort Sea Coast to Shingle in flavour.