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Mackenzie River Inconnu E

Mackenzie River Inconnu E

DFO Science Central and Arctic Region Stock Status Report D5-04 (1998)

A d m / u 1 n 2 Peninsula d s e n Mackenzie { 3 Delta

4 Horseshoe 5 G Bend u l R 6 f Inu vialuit l e a e c

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A e

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Mackenzie Inconnu e

G w ich'in d 7 8

Nunavut

R The

i v e Ramparts Background r 9 G ea t B ea R Great Bear 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 13 4 5 Fort McPherson Great Slave Inconnu are most abundant in large silty northern 6 7 Lake

8 Colville La ke 14 S and associated . The adults are l 9 a South 10 Tulit'a e voracious predators feeding mainly on small fishes

Slave 11 Delin e R 12 i v (McPhail and Lindsey 1970). Anadromous inconnu 13 e 14 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 and its major Shingle Bay . 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 ( 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 (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 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. Survey respondents stressed the Point (Chiperzak 1998a, Chiperzak 1998b, importance of inconnu for human and dog Howland 199a, Howland et al.unpublished food. Inconnu caught in spring and summer (a)). This stock appears to migrate through are used primarily for human consumption the West Channel of the Mackenzie Delta and fish caught in the fall are used primarily between spawning and overwintering areas. for dog food. Fishers stated that the act of It is probably exploited by the Inuvialuit and fishing for inconnu was important for Gwich’in food fisheries and, to a much lesser maintaining a traditional lifestyle (Simon degree, by the commercial fishery in the 1998, Gwich’in Renewable Resource Board Mackenzie Delta. It should probably be 1997). Views of fishers from the Inuvialuit managed as a single stock. and Deh Cho Settlement Regions are unknown. Inconnu that spawn in the , (designated as D5-02) and near the Ramparts Resource Status in the mainstream Mackenzie River (designated as D5-03) are anadromous. The Mackenzie River flows northward from They probably migrate through the East and Great to the Beaufort Sea. Middle channels of the Delta towards Inconnu spawn in the largest tributaries: the spawning areas in the spring and early Peel River, Arctic Red River and Liard summer. They then return to overwintering River. Spawning may also occur in the areas in the east side and middle of the mainstream Mackenzie River. Before Mackenzie Delta towards Tuktoyaktuk reaching the Beaufort Sea, the river branches (Chiperzak 1998a, Chiperzak 1998b, into the Mackenzie Delta, a 12,170 square Howland 1997a, Howland et al. unpublished

4 Central and Arctic Region Mackenzie River Inconnu

(a)). Radio tagging data (Chiperzak 1998a, by their late teens (Bond 1982, Hatfield et al. Howland 1997a and Howland et al. 1972, Howland et al.unpublished (b), Jessop unpublished (a)) indicates that these fish are et al. 1973, Stein et al. 1973 and Stewart et almost certainly a mixture of at least two al. 1997). Females grow slightly faster than discrete stocks of inconnu, an Arctic Red do males and they live longer, therefore River stock (D5-02) and a Ramparts stock females attain a larger size (Hatfield et al. (D5-03), and should be managed with this in 1972, Stein et al. 1973, Howland et al. mind. The Ramparts stock may be composed unpublished (b) and Stewart et al. 1997). of fish with different life history strategies with some fish being non-anadromous Anadromous Mackenzie River inconnu first (riverine) and some being anadromous. start to mature at 6 years of age (Stein et al. These inconnu are probably harvested in a 1973 and Percy 1975). Howland et al. mixed-stock fishery by the Inuvialuit, (unpublished (b)) and Howland (1997a) Gwich’in, perhaps the Sahtu at Fort Good reported that male inconnu in the Arctic Red Hope and to a much lesser degree, the River began to mature at age 7 years and commercial fishery in the Mackenzie Delta. females at age 11 years. Male inconnu in mature at a younger age (5 to 9 Inconnu from the Fort Simpson area of the years) than do female inconnu (7 to 12 years) mainstream Mackenzie River, designated as (Alt 1973). In contrast to Mackenzie River F5-01, appear to be mainly riverine. They inconnu, the heavily exploited Buffalo River may migrate to and from spawning grounds inconnu in mature in the although a small relatively early, with most males and females proportion of the population may starting to mature at age 5 years but as early occasionally make seaward migrations as age 4 years. All Buffalo River male (Chiperzak 1998a, Chiperzak 1998b, inconnu were mature by ages 6 to 7 years Howland 1997a, Howland et al. unpublished and all females by ages 7 to 8 years (Day and (a)). This riverine form is relatively Low 1993). sedentary in comparison to lower Mackenzie Almost all recorded age and length River stocks and is probably harvested frequency distributions of migratory primarily by the Deh Cho and, perhaps to a Mackenzie River inconnu have strong lesser degree, by the Sahtu. It could probably representation of many age and length be managed as a single stock. classes, especially of larger and older fish. There is no indication of pronounced Stock Trends between-year variation in recruitment or of recruitment failure. This observation applies In the Mackenzie River, where fishing to data collected in the early 1970’s through mortality is low, inconnu are long lived and to the present and indicates low fishing frequently reach ages in the mid-twenties. mortality and a high degree of stability in the According to Gwich’in traditional fishery and recruitment. knowledge, inconnu or Sruh (Gwich’in language) can reach 1.2 m in length, weigh Inconnu from Aklavik (Stein et al. 1973), 18 kg and take 2 people to carry (Gwich’in Arctic Red River (Hatfield et al. 1972, Stein Renewable Resource Board 1997). Growth et al. 1973), the Ramparts and Little is rapid and linear at all Mackenzie River Chicago areas of the Mackenzie River locations where inconnu have been sampled. (Stewart et al. 1997) exhibit modal lengths These fish attain lengths of 800 mm or more ranging from 700 to 750 mm and modal ages

5 Central and Arctic Region Mackenzie River Inconnu ranging from 14 to 22 years. Relatively their consumption. There is no indication young and small fish have been observed in that any of these sources of perturbation Tuktoyaktuk harbour (Bond 1982), the Fort have occurred or had any impact on Simpson area (Stein et al. 1973, Jessop et al. Mackenzie River inconnu populations. 1973) and a fall sample taken in the However, they warrant mention because they Ramparts area (Stewart et al. 1997). have been raised as potential concerns. However, these inconnu samples were taken Logging near spawning grounds could at times when the larger spawners are usually reduce egg survival by producing stream absent and are not the result of depletion by bank erosion, siltation and warmer water overfishing. It may also be possible that temperatures. Water pollution, resulting some of the inconnu stocks found in the from mining operations, and blocked access upper Mackenzie attain smaller maximum to migratory corridors, resulting from road sizes. development, could also reduce spawning Total annual mortalities of inconnu, derived success. Climate change could raise water from catch curves for the 1989 to 1993 temperatures in spawning areas. Information Horseshoe Bend fishery, ranged between on the impact of climate change on the 0.22 and 0.30 and total instantaneous rates Mackenzie River Basin can be found in of mortality ranged between 0.25 and 0.35 Cohen (1997). Howland’s (1997b) research (Howland et al. unpublished (b)). The Great is especially relevant to the impact of climate Slave Lake historical natural mortality rate of change since this work has demonstrated that pristine inconnu populations is 0.18 (Day and temperatures required for successful Low 1993) therefore, the total annual fishing incubation of inconnu eggs vary amongst mortality of populations harvested at stocks. Horseshoe Bend is assumed to be low and in the range of 0.04 to 0.12. Total annual Management Considerations fishing mortalities experienced by other The characteristically long migrations of inconnu populations along the Mackenzie, anadromous inconnu from the Mackenzie although not yet calculated, are probably Delta and Beaufort Sea coast to spawning also very low, as indicated by the healthy sites in the mainstream Mackenzie River and representation of older and larger fish found its tributaries means that these stocks are in samples from these populations. likely harvested by beneficiaries of several land claim areas. Of these stocks, the Peel Although the food fisheries and, to a lesser River inconnu should be managed as a single degree, the commercial fisheries exploit a stock whereas the Arctic Red and Ramparts critical productive component of Mackenzie inconnu should be managed as a mixed-stock River inconnu stocks, current- year spawners fishery. The riverine Ft. Simpson stock and post-spawners moving to and from the should be treated as a single stock. spawning grounds, fishing mortality is extremely low resulting in healthy stocks. At present levels of harvest, fishing mortality Other Considerations is extremely low. Populations contain many age and length classes of mature inconnu that Fishers have expressed concerns that habitat are the important recruit producing degradation, pollution and climate change, component of Mackenzie River inconnu should they occur, would harm inconnu stocks. Mackenzie River inconnu can populations and result in reduced fishing probably sustain rates of harvest that are success and or health risks associated with higher than present rates but caution should

6 Central and Arctic Region Mackenzie River Inconnu be exercised. The rate of sustainable harvest Renewable Resource Board and will examine has not been estimated and its calculation is spawning areas, habitat use and inconnu confounded by the complexity of stock stock structure. The Gwich’in Renewable structure and migration patterns and by the Resource Board is also planning a tagging highly variable spatial and temporal regimes study to determine migration patterns, of the fishery. spawning areas and to monitor harvest in the Peel River. The study of key index stocks Howland et al. (unpublished (a)) stress the should prove to be a useful tool for future importance of conserving critical inconnu assessment of Mackenzie River inconnu spawning areas for the continued production stocks. and health of Mackenzie River inconnu. Location and protection of these habitats For more Information: should be the first priority for the conservation of this valuable resource. Contact: Chris Day Department of Fisheries and The Sahtu and Gwich’in have expressed Oceans concern about potential detrimental effects Freshwater Institute that pollution, climate change and habitat 501 University Crescent destruction would have on their ability to Winnipeg, Manitoba harvest inconnu as a traditional source of R3T 2N6 food. Tel: 204-983-5158 Outlook Fax: 204-984-2403 E-Mail: [email protected] The outlook for Mackenzie River inconnu and inconnu fisheries is excellent at present References levels of harvest. Stocks should remain healthy and productive if critical spawning Alt, K.T. 1973. Age and growth of inconnu areas in the mainstream Mackenzie River and (Stenodus leucichthys) in Alaska. Journal of its tributaries and critical nursery, feeding the Fisheries Research Board of 30: and over-wintering areas in the Mackenzie 457-459. Delta are protected from habitat degradation. Bond, W.A. 1982. A study of the fish More information on the biology of resources of Tuktoyaktuk Harbour, southern Mackenzie River inconnu is needed to Beaufort Sea coast, with special references to effectively manage and conserve this life histories of anadromous coregonids. valuable and sustainable resource. In co- Canadian Technical Report of Fisheries and operation with the Department of Fisheries Aquatic Sciences 1119: vii + 90 p. and Oceans, several research projects are planned or being conducted. Ms. K.L. Chiperzak, D. 1998a. Radio tagging study Howland is conducting research on salinity summary of inconnu migration in the Beaufort tolerance, egg development, genetics and life Sea, outer Mackenzie Delta, the Peel River and history variation of anadromous and non- Arctic Red River, 1996. Unpublished Report, anadromous (freshwater) inconnu stocks at Canada Department of Fisheries and Oceans. the University of . A Campbell Lake Inuvik, NT., 36 p. study is being developed by the Gwich’in

7 Central and Arctic Region Mackenzie River Inconnu

Chiperzak, D. 1998b. Preliminary results of system. Submitted to Canadian Journal of scanning proton microscope analysis of Fisheries and Aquatic Sciences. strontium in inconnu otoliths from the Mackenzie River system. Unpublished Rep., Howland, K.L., Treble, M.A. and R.F. Can. Dept. Fish. and Oceans. Inuvik, NT., 3 p. Tallman. Unpublished (b). A biological analysis and population assessment of Cohen, S. (ed.) 1997. Mackenzie Basin impact , inconnu and study: Final report. Atmospheric from the Mackenzie Exploratory Environmental Service, Environment Canada. Fishery, 1989-1993. Submitted to Canadian Downsview, Ontario, Canada. 372 p. Technical Report of Fisheries and Aquatic Sciences. Day, A.C. and G. Low. 1993. The Great Slave Lake commercial inconnu, Stenodus Jessop, C.S., Porter, T.R., Blouw, M. and R. leucichthys, fishery. Canadian Manuscript Sopuck. 1973. Fish resources of the Report of Fisheries and Aquatic Sciences No. Mackenzie River Valley: An intensive study of 2224: 24-25. the fish resources of two mainstream tributaries. Environmental-Social Committee, Gwich’in Renewable Resource Board. 1997. Northern Pipelines, Task Force on Northern Nanh’Kak Geenjit Gwich’in Ginjik. Gwich’in Oil Development. Special Report. 148 p. Words About the Land. Gwich’in Graphics, Inuvik, NT. 212 p. McPhail, J.D., and C.C. Lindsey. 1970. Freshwater fishes of Northwestern Canada and Hatfield, C.T., Stein, J.N., Falk, M.R., Jessop, Alaska. Bulletin of the Fisheries Research C.S. and D.N. Shepherd. 1972. Fish resources Board of Canada 173, x + 381 p. of the Mackenzie River Valley: Interim report I, Vol. II. Prepared by Department of the Nelson, J.S. 1976. Fishes of the world. John Environment, Fisheries Service, Winnipeg, Wiley and Sons, Inc., United States of MB. 289 p. America. 416 p.

Howland, K.L. 1997a. Migratory patterns of Percy, R. 1975. Fishes of the outer Mackenzie freshwater and anadromous inconnu, Stenodus Delta. Beaufort Sea Project, Technical Report leucichthys, within the Mackenzie River No. 8. Beaufort Sea Project Office, Victoria, system. MSc. Thesis, University of Alberta, BC. 114 p. , Alberta. 96 p. Scott, W.B. and E.J. Crossman. 1973. Howland, K.L. 1997b. Life history variation of Freshwater fishes of Canada. Fisheries inconnu, Stenodus leucichthys, in the Research Board of Canada Bulletin 184. Mackenzie River system: Genetic or 966 p. environmental basis? PhD Proposal/Progress Report. University of Alberta, Edmonton, Simon, P. 1998. Questionnaire results: Alberta. 13 p. Community concerns on coney (inconnu) in the Gwich’in Settlement Area. Unpublished Howland, K.L., Tallman, R.F. and W.M. Tonn. Report, Gwich’in Renewable Resource Board, Unpublished (a). Migratory patterns of Inuvik, NT. 16 p. freshwater and anadromous inconnu, Stenodus leucichthys, within the Mackenzie River

8 Central and Arctic Region Mackenzie River Inconnu

Stein, J.N., Jessop, C.S., Porter, T.R. and K.T. J. Chang-Kue. 1973. Fish resources of the Mackenzie River Valley. Interim Report II. Prepared by Department of the Environment, Fisheries Service for the Environmental Social Program, Northern Pipelines. 260 p.

Stewart, D.B., Low, G., Taptuna, W.E.F., and A.C. Day. 1997. Biological data from exploratory fisheries at Special Harvesting areas in the Sahtu and Metis Settlement Area, NWT.: Volume 1. The Upper Ramparts and Little Chicago areas of the Mackenzie River. Canadian Data Report of Fisheries and Aquatic Sciences 1020: vi + 61 p.

Taptuna, F., and G. Low. 1995. A fishery survey of the Sahtu communities. Unpublished Report, Canada Department of Fisheries and Oceans, Hay River, NT. 52 p.

This report is available: Freshwater Institute c/o Susan Cosens Central and Arctic Region 501 University Crescent Winnipeg, Manitoba R3T 2N6 Tel: (204) 983-8838 Fax: (204) 984-2403 [email protected] www.dfo-mpo.gc.ca/csas

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