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Nunavik) Beluga (Delphinapterus Leucas

Nunavik) Beluga (Delphinapterus Leucas

Fisheries Pêches and Oceans et Océans DFO Science Laurentian Region Stock Status Report E4-01(2001)

82° 80° 78° 76° 74° 72° 70° 68° 66° 64° 62° 60° 58°

64° 64° ÊÚ Eastern $T Hudson Strait Digges Island #S H u # d %U Closed in 1978 T$ so T$ n S t 62° ra 62° it Kangirsujuaq T$

T$ Hudson ÊÚ Akulivik Quartaq Bay %UKilliniq

60° ÊÚPuvirnituq Kangirsuk S# 60° Ungava

Aupaluk S# Bay

Tasiujaq S# S# Kangirsualujjuaq Northern () ÊÚInujjuaq # S# Mucalic 58° 58° Beluga (Delphinapterus leucas) Sea Belcher Islands # Nastapoka River N ÊÚUmiujaq # W E 56° # 56° S ÊÚKuujjuaraapik Background 0 200 400 600 800 1000 Kilometers Beluga whales are found in summer along the 54° 54° Hudson Bay coast, in and in Ungava Bay. 82° 80° 78° 76° 74° 72° 70° 68° 66° 64° 62° 60° 58° The majority of the animals from all areas are Figure 1. Map of communities in northern Quebec thought to overwinter together in Hudson Strait. At (Nunavik) least three separate stocks of beluga have been identified (Ungava Bay Beluga, Eastern Hudson Bay Beluga and Western Hudson Bay Beluga); each Summary stock recognised by the tendency of beluga to home • Aerial surveys flown in 1993 provided a in summer at a particular estuary or group of visible abundance estimate (uncorrected estuaries. COSEWIC accepted this separation of stocks. In 1988, the Ungava Bay stock of Beluga for diving) of 1,000 (SE=400) in eastern were classified as endangered, while the eastern Hudson Bay (EHB), and 3,100 Hudson Bay stock was identified as threatened (SE=800) whales in James Bay. Too (Reeves and Mitchell 1989). few whales were seen in Ungava Bay to provide a survey estimate, but numbers In addition to the traditional subsistence hunt commercial hunts operated in Ungava Bay from the are likely less than 200 animals. Beluga 1860’s until the early 1900’s and removed at least whales in western Hudson Bay have not 1,340 animals . The numbers of beluga killed been surveyed since the 1980s. These appear to have declined owing to depletion of the surveys provided a visible abundance stock. Commercial hunting at the Little Whale and estimate of 23,000 animals. Beluga Great Whale , in eastern Hudson Bay removed an estimated 8,294 animals between 1854 and 1868. whales were also seen in northern Commercial hunting continued at Hudson Bay (N=700), and along the until at least 1877, but apparently ended owing to Ontario coast of Hudson Bay (N=1,300). depletion of the stock. The stock relationships of beluga in the Hudson Bay-James Bay-Ungava Bay The beluga hunt in northern Quebec has been regulated by a five-year management plan, which complex are poorly understood. regulates harvests through a combination of area • A 5-year management plan limited closures, controlled seasons and village quotas. The harvesting of beluga whales to a total of current plan ends in March 2001. The intention of this report is to provide scientific advice on northern 240 whales per year. However, Quebec beluga for the new management plan to be reported harvests consistently exceeded implemented in 2001. this total ranging between 267 and 302 belugas per year.

April 2001 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas)

• There is considerable uncertainty waters. They are often associated with associated with current abundance , the estuaries, which has lead to the view that rate of increase of the population, factors they are a shallow water species. However, associated with correcting survey aerial surveys and satellite telemetry estimates to account for animals below indicate substantial movements offshore and the surface, and the fraction of the diving to depths of over 600 m. harvest in the different communities made up of animals that belong to the The Hunt different beluga stocks. Harvest statistics are available since 1974. • In spite of these uncertainties, the EHB These statistics represent minimum beluga population has likely declined estimates only, since not all villages from 2,200 (95% C.I. 1,900-2,600) provided catch data in all years and whales in 1985 to 1,400 (95% C.I. 500- information on the number of animals struck 2,300) in 2000. Current levels of and lost is incomplete. During the 12 year harvesting of the eastern Hudson Bay period 1974-1985, a total of 4,808 whales population are likely not sustainable. (average=401 whales/yr) was reported to • Harvesting of eastern Hudson Bay have been taken . Catches declined animals, particularly at the estuaries beginning in 1978 in Ungava Bay, Hudson should be reduced substantially. Strait and Hudson Bay villages. A management plan to reduce harvesting was • New abundance estimates are needed introduced in 1986, and reported catches along with information on the stock declined to a total of 2,255 (average composition of the harvest, the =225/yr) during the period 1986-95. In relationship of beluga in James Bay to 1996, a 5 year management plan was the other beluga stocks in Hudson Bay- introduced. This plan limited harvesting to Hudson Strait-Ungava Bay complex 240 animals per year for the Nunavik region. A quota of 90 animals was allocated Species biology to villages along the eastern Hudson Bay Beluga whales have a circumpolar coast (18 per village), 100 animals to the distribution. They are a medium-sized four villages in Hudson Strait and 50 toothed whale with an adult length of 350 animals to communities in Ungava Bay. cm. The calves are born after a 14 month Hunters were to direct harvesting away from gestation and lactation lasts for roughly 18 young animals or females with calves and months. The calving interval is one calf towards large males. Hunters in Ungava every 3 years. At birth, the calves have been Bay were encouraged to take animals described by different authors as being outside of the bay. Total harvests during the brown or dark bluish in colour. As they current plan have been 1,424 animals for an mature the skin becomes lighter in colour average of 285 whales per year. (Table 1). gradually turning to grey then to white. Prior to 1996, hunters in eastern Hudson Beluga are sexually mature between 4 and 7 Bay took most of their animals near their years of age. At this time some animals may communitiy or from the Nastapoka, and still be grey in colour. In the EHB Little Whale Rivers and Richmond Gulf. population 57% of the light grey animals Under the current management plan, the may be sexually mature. communities of Akulivik and Puvirnituk have shifted their hunting effort to the Beluga lack a dorsal fin, which is believed Hudson Strait area near Ivujivik. Depending to be an adaptation to inhabiting ice covered on the region, grey beluga (<7 years old)

2 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas) represented 46 to 51% of harvests, and which is much older than the median age of females, 47 to 60% of 8.0 (N=69) for animals harvested during the 1990s (Fig. 2). A characteristic of beluga is Table 1. Beluga harvest statistics for Nunavik villages an increase in wear of the teeth as the from 1984-2000 (Lesage et al. 2001). animals become older. This leads to an underestimate of the true age among older YEAR 96 97 98 99 2000 animals. During the 1980s, 48% of the teeth 15 11 14 14 8 from harvested animals were worn. This Umiujaq 19 19 18 24 19* proportion declined to 28% of the teeth from Inukjuak 22 21 18 19 35 animals harvested during the 1990s. Puvirnituk 38 33 36 27 29 Akulivik 15 24 17 22 12 Figure 2. Age of beluga harvested in Eastern Eastern Hudson 109 108 103 106 103 Hudson Bay during 1980, 1983–1987 (black bars and plain curve and 1993–1999 (clear bars and Bay total dotted curve), presented as age frequencies (bars) Ivujivik 34 22 44 37 36 and cumulative frequencies (curves). Salluit 32 46 54 33 28 Kangiksujuaq 25 25 22 27 26

Quaqtaq 23 31 32 24 26 26 1.0 24 Hudson Strait 114 124 152 121 116 0.9 22 total 0.8 20 18 0.7 Kangirsuk 16 16 13 19 12 16 0.6 14 Aupaluk 8 8 4 13 8 0.5 12 Tasiujaq 6 14 17 21 13 10 0.4

Number of animals 8 0.3

Kuujjuak 5 13 10 8 7 Cumulative frequency 6 Kangiksualujju 973 7 11 0.2 4 aq 2 0.1 Ungava Bay 44 58 47 68 51 0 0.0 0 3 6 9 12 15 18 21 24 27 30 33 Age (GLG's / 2) total Resource User Perspective Nunavik total 267 290 302 295 258 Beluga are considered as an important food resource by in northern Quebec. There is community concern regarding catches during 1993–2000. The proportion contaminants and disease agents that could of white males (23—30%) in harvests was affect the health of belugas or their human near the percentage expected if animals consumers. Other global issues of concern, were taken at random (i.e. 25%) during include climate change and the resultant 1995—2000. A comparison between the changes in sea ice, which might affect whale 1980s and the 190s of the age frequency movements, their foods and hunter access to distributions of beluga harvested in eastern whales. During community consultations Hudson Bay, indicates a statistically concerns were also expressed about the significant change in the age composition of increase in vessel traffic, from both small the harvest. During 1980–1987, the median boats and large ships, the resulting noise age of beluga taken by the Nunavik villages pollution and how this noise might disturb in eastern Hudson Bay was 13.0 (N=132), beluga, particularly in nearshore areas.

3 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas) Concerning beluga whale abundance, there maternally inherited “haplotypes” and also were a wide range of opinions. Some with 15 nuclear microsatellite loci in which people indicated that there has been no alleles at each locus are inherited from both change in numbers of animals, or that more parents. The molecular genetics of 100 animals are seen now than before. Several belugas from Sanikiluaq, a community people expressed concern that fewer animals located in the Belcher Islands (Fig. 1), 126 were seen now than many years ago. from villages in EHB, 137 from northern However, it is not clear whether changes in Quebec and Hudson Strait, and hundreds sightings are a result of a reduction in from other locations in the have been beluga abundance or animals have moved examined. Results support the hypothesis elsewhere due to noise pollution. that most belugas hunted in EHB and Sanikiluaq are from different stocks. Beluga in northern Quebec have been Belugas from the Nastapoka River (1984- managed under a five year management 1985) and from the EHB arc (1990s) are plan. This plan was considered by resource characterized by high proportions of two users to be too long and unwieldy. In haplotypes which are uncommon in other response, a multi-year plan outlining areas. Belugas hunted near Sanikiluaq management and science objectives has (1993-1997) are different from EHB beluga been proposed, with quotas to be established and may represent a different stock which annually. also differs from other western Hudson Bay populations that have been examined.

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1000 Population

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0 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Year

Figure 3. Predicted changes in population size if current harvest levels continue. The middle line is the mean. The inner shades represent plus or minus 1 standard deviation.The outer shades represent the 95% confidence limits. Genetic results from both EHB and Resource Status Sanikiluaq (Belcher Islands) were consistent Two genetic techniques have been used for over the years that they were sampled . stock delineation. Individuals and Approximately 10% of belugas hunted from populations were characterized with a Sanikiluaq have EHB genotypes, and 16% mitochondrial DNA (mtDNA) d-loop of belugas hunted in the EHB arc have sequence of 324 base pairs which described genotypes that resemble western

4 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas) populations. Belugas hunted in Hudson factor of 2.09 (SE=0.16). Strait villages have a high genetic diversity, confirming that several stocks are hunted Information on abundance from the aerial here. It is estimated that Hudson Strait surveys, factors to correct aerial survey villages hunt approximately 30% EHB estimates for animals under the water, belugas, but sample sizes are still quite low. harvest data and the proportion of EHB animals in the harvest were incorporated Visual strip transect surveys completed in into a population model to describe changes 1985, were used to estimate a visible in the population since 1985 (Fig. 3). population rounded to the nearest 100, of Beluga in eastern Hudson Bay have likely 1,200 (SE=300) in James Bay, and 1,000 declined from 2,200 (95% C.I. 1,900-2,600) animals (SE=200) in eastern Hudson Bay. animals in 1985 to 1,400 (95% C.I. 500- Numbers of animals seen in Ungava Bay 2,300) in 2000. If current levels of were too few to provide an estimate for this harvesting continue then this population area (Smith and Hammill 1986). A second could disappear in the next 10-15 years. series of aerial surveys flew the same transect lines in August 1993, but used line- Sources of uncertainty transect techniques instead of strip-transect There is a considerable amount of methods (Kingsley 2000). The estimated uncertainty associated with the available visible population was 3,300 belugas data. Abundance estimates for this stock are (SE=800) in James Bay, and 1,000 animals limited to two aerial surveys, flown eight (SE=400) in eastern Hudson Bay. Again, years apart, which used the same transect too few animals were seen in Ungava Bay to lines, but applied different survey estimate population size, but numbers were techniques. The most recent survey was likely less than 200 animals. No recent flown in 1993. estimates of abundance for beluga in western Hudson Bay are available, but The aerial surveys indicate that a surveys flown in the 1980's suggested that considerable proportion of the surveyed numbers were greater than 23,000 animals. beluga population are found offshore and that some animals are located near Correction factors are required to estimate Sanikiluaq. However, most animals total population size. These correction harvested in the Sanikiluaq area do not factors account for animals under the water, belong to the eastern Hudson Bay stock. and consequently not visible, when the This would indicate that the aerial survey survey plane passes overhead. The survey estimates include animals from more than platform, animal behaviour, water turbidity, one beluga stock. If this is the case, then it and the ranges at which sightings occur will suggests that the eastern Hudson Bay beluga affect these factors. Correction factors stock is smaller than originally thought. derived from satellite telemetry vary between 1.42 in the High Arctic, and 5.0 for Data on the appropriate correction factor to surveys conducted during the fall when apply to aerial survey estimates to account animals spend less time at the surface. A for animals not visible at the surface are factor of 1.66 (SE=0.12) has been suggested limited and have not been thoroughly for Hudson Bay. In the St Lawrence estuary reviewed. In this analysis an estimate of a study using aerial observations of 2.09 (SE=0.16), developed for beluga in the anchored models and overflights of St Lawrence estuary was used. individual animals estimated a correction

5 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas) Communities north of the Hudson Bay arc If current levels of harvesting continue then and in Hudson Strait are hunting beluga the EHB population could disappear in the from both the small EHB stock and the large next 10-15 years. To halt the apparent western Hudson Bay stock. A sensitivity decline harvesting of EHB beluga should be analysis showed that changes in the reduced substantially. A reduction in total percentage of EHB animals had a major removals from this population to 40 animals impact on predictions of changes in the per year is sustainable. However, a population trends. Initial estimates from reduction in total removals to 20 animals per genetic analyses indicate that about 30% of year would probably allow the population to the beluga harvested by northeastern increase and is recommended owing to Hudson Bay and Hudson Strait communities uncertainties in model parameters. These may be from the EHB stock, but these are recommendations are for total removals. based on small sample sizes. More The incorporation of a factor for struck and information on the stock composition of the loss would result in a lower quotas being harvest is needed from the Hudson Strait assigned to each village. communities in order to assess the impact of hunting on the EHB population. Northern Quebec beluga have been managed under a 5-year management plan. Beluga in Owing to the lack of a time series of Ungava Bay were classified as endangered. estimates of beluga abundance and the The low potential for growth of beluga absence of information on rates of increase, populations means that it is unlikely that this values for rmax from other toothed whale population has increased. Therefore, species were used during model simulations. current management requirements that These provided a range of possible rates of hunting occur outside of the Bay should increase, but obviously contributed to continue. A reduction in harvesting on the uncertainty about how population size may EHB population is needed if this stock is not have changed over time. to decline further. Reducing harvests at the Nastapoka and Little Whale Rivers, Harvest statistics are available since the including the possibility of closure to 1970's. However, it is not possible to assess hunting is recommended. However, if the degree of non-reporting of struck current overharvesting is to be reduced, the whales. Furthermore, although few animals management plan will need the support of harvested in estuaries may be lost due to a the harvesters along with appropriate tradition of first harpooning animals, enforcement. harvests from the Hudson Strait area occur in more open water, where animals are not Other considerations always harpooned first. Struck and loss data There is an urgent need for information on for beluga are limited, but for narwhal in the abundance, and stock structure of some areas, the number of animals struck beluga along the Hudson Bay coast and in and lost may approach 50%. There is no James Bay. A biological sampling program information on the number of belugas that aimed at understanding the stock are struck and loss in northern Quebec. This composition of the Nunavik harvest should lack of information increases the uncertainty be maintained. Efforts should be expanded of total removals from the population. to improve the documentation of harvesting in the Hudson Strait area. Outlook

6 Laurentian Region Northern Quebec (Nunavik) Beluga (Delphinapterus leucas) Information on abundance of western Ass. Secr. Res. Doc. 2001/022. 52 Hudson Bay dates from the 1980s. If pp. harvesting of this stock by Nunavik hunters is being encouraged, an update on WHB Reeves,R.R. and E.D. Mitchell. 1989. beluga population abundance is needed. Status of white whales, Delphinapterus leucas, in Ungava For more Information Bay and eastern hudson Bay. Can. Contact: M.O. Hammill/ V. Lesage Field-Nat. 103:220-239. Maurice Lamontagne Institute P.O. Box 1000, Mont-Joli, QC Smith, T.G. and M.O. Hammill. 1986. G5H 3Z4 Population estimates of white whale, Delphinapterus leucas, in Tel: (418) 775-0500 James Bay, Eastern Hudson Bay Fax: (418) 775-0740 and Ungava Bay. Can. J. Fish. E-Mail: Aquat. Sci. 43:1982-1987. [email protected]. [email protected]. This report is available from the:

References Regional Stock Assessment Office, de March1, B.G.E., L.D. Maiers1, M.O. Department of Fisheries and Oceans Hammill2, and D.W. Doidge3. 2001. Maurice-Lamontagne Institute Stock discrimination of belugas P.O. Box 1000, Mont-Joli (Delphinapterus leucas) hunted in Quebec, eastern Hudson Bay, northen G5H 3Z4 Québec, Hudson Strait, and Sanikiluaq (Belcher Islands), using e-mail: [email protected] mitochondrial DNA and 15 nuclear Internet: http:/www.dfo-mpo.gc.ca/csas microsatellite loci. Can. Stock. Ass. Secr. Res. Doc. 2001/050. ISSN 1480-4913

Hammill, M.O. 2001. Beluga in Northern Quebec: Impact of harvesting on La version française est disponible à l’adresse population trends of beluga in ci-dessus. eastern Hudson Bay. Can. Stock. Ass. Secr. Res. Doc. 2001/025. 18 pp. Correct citation for this publication Kingsley, M.C.S. 2000. Numbers and distribution of belugas in Hudson DFO.2001. Northern Quebec (Nunavik) Bay, James Bay and Ungava Bay in Beluga (Delphinapterus leucas). DFO Canada during the summer of 1993. Sciences Stock Status Report E4-01(2001) Fish. Bull. 98: 736-747.

Lesage, V., W.D. Doidge, and R. Fibich. 2001. Harvest statistics for beluga in Nunavik, 1974-2000. Can. Stock.

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