Cumberland Sound Beluga
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Central and Arctic Stock Status Report E5-32(2002) Baffin Island (Nunavut) Clearwater Fiord Pangnirtung Nettilling Fiord Cumberland Sound Beluga C u Presumed winter range m be Approximate summer rla range nd S ou H nd Background al l P en in Historically, belugas in Cumberland Sound were su la hunted both commercially and for subsistence. In 1990, the Southeast Baffin – Cumberland Sound beluga population was designated as Fig. 1. Distribution of Cumberland Sound “Endangered” by the Canadian Committee on belugas during summer and winter the Status of Endangered Wildlife in Canada months. (COSEWIC) following declines in beluga numbers estimated from aerial surveys data. Summary Until recently, Cumberland Sound belugas were thought to belong to a Southeast Baffin Island • Recent data on movements obtained population that was hunted by the communities from tagged whales suggest that of Iqaluit and Kimmirut as well as by belugas reside in Cumberland Sound Pangnirtung. Growth measurements, genetic year-round. and contaminants profiles, and satellite tracking data, collected since the late 1980s, have • Growth measurements and genetic confirmed that most belugas hunted in and contaminant profiles, collected Cumberland Sound are distinct from those since the 1980s, have confirmed that hunted near Iqaluit and Kimmirut. Local hunters, most belugas hunted in Cumberland however, report that there are different types of Sound are distinct from those hunted belugas hunted in Cumberland Sound. near Iqaluit and Kimmirut. Local The community of Pangnirtung hunts hunters report there are two or three Cumberland Sound belugas under a quota different types of belugas hunted in system. The hunt is co-managed by the Nunavut Cumberland Sound. Wildlife Management Board (NWMB) and • Between 1992 and 2001, hunters Fisheries and Oceans Canada (DFO). Hunting regulations are implemented by DFO under the landed an average of 36.5 belugas Fisheries Act and the Marine Mammal each year. Struck-and-lost rates Regulations. A quota of 35 belugas has been in were not reported. During the same force for this population since 1991. As of the period, belugas were also taken 2002/03 hunting season, the quota has been occasionally during ice entrapments. increased to 41 as part of a community-based management system. This RAP is being done in • Aerial surveys, conducted in 1999, support of this management requirement. produced a population estimate of 1547 belugas (95% confidence limits: 1187-1970). Local knowledge and comparison of the 1999 estimate October 2002 Central and Arctic Cumberland Sound Beluga to earlier estimates both suggest the hunters report that females may give population is increasing in size and birth annually (Kilabuk 1998). The recovering from historic depletion by population growth rate is not known commercial whaling. exactly for this population. • The DFO and the NWMB have authorized an increase in quota from The oldest female and male sampled 35 to 41 belugas, starting in 2002, as from the catch in Cumberland Sound to part of a community-based date are 26 and 24 years respectively management system. (R. Stewart, unpublished data). In many stocks, belugas live to be 35-40 years of Species Biology age or older (Smith 1999). A 49-year-old female and a 57-year-old animal were The beluga or white whale reported from the Eastern Beaufort Sea (Delphinapterus leucas) (qilaluga in stock (Harwood et al. 2000). Average Inuktitut) is a toothed (Odontocete) annual survival of beluga is reported to whale characterised by a blunt head, range from 90.6% per year for a hunted slight beak, fat, stocky body and lack of stock (Burns and Seaman 1985) to 97% a dorsal fin. Newborn calves are light to per year for a stock that is not hunted dark-mottled grey in colour. Juveniles (Béland et al. 1988). Sources of natural gradually lighten in colour as they age mortality include polar bears (Smith until they become almost pure white 1985, Lowry et al. 1987, Smith and between seven and nine years of age. Sjare 1990), killer whales (Byers and Belugas are usually found in arctic and Roberts 1995), ice entrapments (Porsild subarctic waters and vary 1918, Freeman 1968) and, possibly, geographically in size and weight disease (O. Nielsen, personal (Sergeant and Brodie 1969). In communication). Cumberland Sound, adult females and males reach mean lengths of 362 cm Belugas occupy mostly the western side (11.9 ft) and 428 cm (14.0 ft) of the Cumberland Sound in spring and respectively (Brodie 1971) and weigh early autumn (Fig. 1). In summer, they from 800 to 1000 kg (1750-2200 lbs). are found mainly in Clearwater Fiord Females typically reach sexual maturity and adjacent bays where they are at about 5 (range: 4-7) years of age reported to feed on a variety of fish and (Brodie 1971; Heide-Jørgensen and invertebrate species (Brodie 1970). Teilmann 1994). Males typically reach Based on recent results obtained from maturity at 6-8 years of age (Brodie satellite-tagging studies, belugas spend 1971; Heide-Jørgensen and Teilmann most of their time in the centre of the 1994). Sound in late autumn, then move to the eastern side near the mouth of the In Cumberland Sound, the peak in Sound in early winter. During the late breeding appears to occur in May with autumn and early winter belugas dive to calves being born in late July or early depths of 300 m or more in the middle of August after a gestation period of about Cumberland Sound, likely to feed on 14.5 months (Brodie 1971; Kilabuk deep-water species such as Greenland 1998). Calves nurse for up to two years. halibut, also known as turbot, The calving interval is estimated to be (Reinhardtius hippoglossoides) (P. one calf born every three years on Richard, unpublished data). Local average (Brodie 1971) although local hunters also report that belugas at the 2 Central and Arctic Cumberland Sound Beluga floe-edge in spring prey mainly on Arctic struck and lost and another 14 belugas cod (Boreogadus sp.) and turbot under were wounded but escaped (DFO Iqaluit the ice (Kilabuk 1998). Area Office, unpublished data). It is not known whether wounded animals live or The Hunt die as a result of their injuries. If struck- and-lost and wounded-and-escaped Year Quota Catch rates are similar for the Cumberland Sound hunt, then on average between 1992 35 35 41 (36.5 × 1.13 = 41) and 46 belugas 1993 35 15 (36.5 × 1.27 = 46) actually have died 1994 35 35 from the hunt each year. Despite that, 1995 35 31 the population indices indicate a growth 1996 35 41 of the population in the last decade. 1997 35 47 1998 35 35 Resource User Perspective 1999 35 50 2000 35 37 2001 35 39 The Inuit of the southeast Baffin region have long depended on the hunt of Table 1. Number of belugas struck and landed belugas in Cumberland Sound for their by Pangnirtung hunters between 1992 survival and culture. During the and 2001 (hunt statistics provided by DFO Iqaluit Area Office). commercial whaling period, large numbers of belugas were killed. Hunters see variation in the numbers of belugas The annual quota for belugas in from year to year but they are seeing Cumberland Sound was 35 whales more belugas today than they did in the between 1992 and 2001, and was recent past. Predation by killer whales increased to 41 whales in 2002. As a and disturbance caused by noise from condition of increasing the quota, the numerous motorised boats and community is collecting information on snowmobiles are the primary concerns struck and loss rates and landings. of Pangnirtung hunters for the welfare of Hunters hunt belugas mostly in summer belugas in Cumberland Sound. and avoid taking calves and females Restoring some order, traditional laws with calves. Total landings between and practices in the hunting of belugas 1992 and 2001 fluctuated between 15 and holding community consultations to and 50, averaging 36-37 belugas per make the public more aware of the year (Table 1). Over the same period, problems were two recommendations additional belugas were hunted presented in a recent report on Inuit opportunistically when they became traditional knowledge (Kilabuk 1998). trapped by ice. In addition to belugas Other recommendations presented in that are struck and landed, some whales the report included making traditional are killed but lost. While struck-and-lost knowledge part of the school curriculum, rates have not yet been recorded for the organising community hunts better and Cumberland Sound hunt, data were improving the DFO Whale Sampling collected for other southeastern Baffin Program. Many people that reside in the hunts during 1999-2001. For every 100 vicinity of Cumberland Sound live off the beluga struck and landed by Iqaluit and land and, for that reason, Cumberland Kimmirut hunters, another 13 were Sound has the most outpost camps in 3 Central and Arctic Cumberland Sound Beluga the Region. There may be some interest and just starting to shed. Hunters report in allocating whales for the outpost these animals are noticeably larger and camps separate from the community better than the smaller ones at avoiding quota. hunters. Resource Status During the summer, belugas are also seen in Netilling Fiord and southward in Stock Delineation the bays and coastal waters of the western side of Cumberland Sound. Cumberland Sound belugas, tracked Like the early floe-edge whales, these with satellite-linked tags, do not appear belugas are smaller in size and thinner to range beyond Cumberland Sound. than the Clearwater whales. It is not Genetic and contaminant profiles clear whether these western whales are suggest that belugas, caught in the the same animals as the small whales waters off southeast Baffin Island since seen at the floe edge but the maktaq the late 1980s, belong to a different tastes the same.