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The monodontids--narwhals, Monodon monoceros, and belugas, Delphinapterus leucas--are found in much of the Arctic and in some subarctic areas. They are hunted by indigenous subsistence users. In the past, some populations were substantially reduced by commercial hunting and culling; more recently, some populations have declined due to uncontrolled subsistence hunting and environmental degradation. Monodontids are impacted increasingly by human activities in the Arctic including ship and boat traffic, industrial development, icebreaking, seismic surveys, competition with fisheries, and alteration of habitat due to climate change. Since comprehensive reviews in the 1990's, substantial new information has become available on both species and on changes to their habitat as a result of human activities and climate change. Thus NAMMCO and partners undertook an updated review in 2017. The review recognized 21 extant beluga stocks, 1 extirpated beluga stock, and 12 stocks of narwhals. The available information on each stock regarding population size, depletion level, current and past removals, and trends in abundance was reviewed to determine status. Concern was expressed where the lack of information prevented reliable assessment, removals were thought to be unsustainable, or the population was deemed at risk of declining even without direct removals by hunting. Beluga stocks of greatest concern are the small stocks in Ungava Bay (possibly extirpated), Cook Inlet (ca 300), St. Lawrence Estuary (ca 900), and Cumberland Sound (ca 1,100), and the stocks with uncertainty in Eastern Hudson Bay and the Barents-Kara-Laptev Seas. Narwhal stocks of greatest concern are those in Melville Bay and East Greenland., Introduction The family Monodontidae is comprised of the narwhal, Monodon monoceros, and the beluga or white whale, Delphinapterus leucas (Rice, 1998). These two species are found in much of the [...]

The summer coastal Arctic Char (Salvelinus alpinus) fishery is an important cultural, subsistence, and commercial resource for the community of Ulukhaktok in the Inuvialuit Settlement Region, Northwest Territories. Anadromous Arctic Char are caught while they are feeding along the coast during summer, generally early-July to late-August. A community-based harvest monitoring program was conducted during 1993-1997 and 2011-2015 to collect catchper-unit-effort (CPUE) and biological data from the coastal subsistence fishery. The community has also conducted a small-scale Arctic Char commercial fishery, licensed as a Stage 1 Exploratory Fishery with catch and biological data reporting requirements. Median CPUE in the subsistence fishery ranged from 19.2 to 32.8 Arctic Char/100 m net/24 h, with no trends over time in either sampling period or overall. There was an increase in the length and weight of Arctic Char harvested in the coastal fishery between sampling periods, with the majority of fish between 500 mm and 650 mm, and 1,500 g to 3,000 g in 1993-1997, and between 550 mm and 800 mm and 2,500 g and 5,000 g in 2011-2015. The majority of Arctic Char harvested in the subsistence fishery were between 8 and 13 years. Annual mortality during 2011 to 2015 was relatively stable at a low level (0.17-0.3). In addition to changes in size, there was evidence of increases in growth rate (length-at-age) between 1993-1997 and 2011-2015. Biological data collected from the commercial fishery were similar to those collected from the subsistence fishery although the commercial catch was comprised of a higher proportion of large (= 700 mm) fish which is expected given some differences in gear types. The available information suggests that the populations contributing to the coastal summer fishery are sustainable at present harvest levels. The collection of biological and CPUE data from subsistence and commercial fisheries continues to be a priority for the Ulukhaktok Char Working Group, to support their use of adaptive co-management and enable the sustainable management of their Arctic Char fisheries. Continued monitoring and research, that include both Indigenous Knowledge and scientific methods are required to better understand, characterize, and assess the stocks that contribute to this mixed-stock coastal fishery. [ABSTRACT FROM AUTHOR]

Fish and marine mammals are an important traditional subsistence and cultural resource for residents of Ulukhaktok, a community within the Inuvialuit Settlement Region, Northwest Territories. Community-based harvest surveys were conducted monthly out of Ulukhaktok, between 2004 and 2015, to enumerate fish and marine mammal subsistence harvest. Anadromous Arctic Char (annual average: 3,464 fish), Lake Trout (annual average: 2,114 fish), and Ringed Seals (annual average: 256 seals) continue to be the most abundantly harvested fish and marine mammal species 2004-2015, with landlocked Arctic Char (annual average: 203 fish), whitefish (annual average: 74 fish), cod (annual average: 136 fish), and Bearded Seals (annual average: 8) also reported. Accessibility to harvesting areas and availability of fish and marine mammals were strongly linked to seasonal cycles. Following concerns regarding the population status of Kuujjua River (i.e., Tatik Lake) Arctic Char, and to support the sustainable management of all Arctic Char subsistence and commercial fisheries in the area, the Ulukhaktok Char Working Group (UCWG) was established in 1996. The UCWG implemented a community fishing plan with voluntary management measures and fishery guidelines supported by harvest data provided by monitoring programs. In response to the observed decline in stock status, the UCWG established a voluntary subsistence harvest level of 1,000 fish from Tatik Lake which has not been surpassed in recent years (2003-2015); however, the total number of Kuujjua River Arctic Char harvested is unknown due to the uncertainty regarding contributions to the coastal mixed-stock harvest. Total annual harvest of anadromous Arctic Char from respective management zones 1988-2015 varied as follows: a) between 486 and 6,297 fish in coastal waters; b) between 0 (voluntary community closure) and 4,386 fish from the Kuujjua River; and c) between 0 and 5,502 fish from rivers in Prince Albert Sound. Co-management partners consider all available information collected through harvest surveys, monitoring programs, Indigenous Knowledge and observations, and scientific research to support the adaptive comanagement of these important fish and marine mammal species in a changing climate. [ABSTRACT FROM AUTHOR]

FINAL REPORT OF THE INUIT BOWHEAD KNOWLEDGE STUDY, NUNAVUT, CANADA. By KEITH HAY, DAVID AGLUKARK, DAVID IGUTSAQ, JOANNIE IKKIDLUAK and MEEKA MIKE. Nunavut Wildlife Management Board, Iqaluit, Nunavut, Canada X0A [...]

Data collected from a fishery-dependent monitoring program between 1992 and 2015 and supplemental information collected in 1978 and 1987 were used to inform a population assessment of anadromous Arctic Char (Salvelinus alpinus) from the Kuujjua River, Northwest Territories. The stock is important for the subsistence and economy of residents from the hamlet of Ulukhaktok in the Inuvialuit Settlement Region. Arctic Char from the Kuujjua River stock are harvested during summer when feeding along the coast in a mixed-stock fishery, and during winter (under-ice) while overwintering in Tatik Lake. The monitoring program conducted during the winter fishery employed subsistence fishers from Ulukhaktok to collect harvest, catch-effort, and biological data for the majority of the duration of the fishery. Catch-effort in Tatik Lake varied without trend although the frequency of relatively high values (> 125 Arctic Char/100 m/24 hours) increased from 2006 to 2015. The biological data reveal the winter fishery harvests Arctic Char mainly between 500 and 700 mm, 1,000 and 3,500 g, and 8 and 12 years of age. Mean length and weight increased from 533 to 633 mm and 1,893 to 3,354 g, respectively, between 2008 and 2012, and have been relatively stable through 2015. Mean age increased from 8.3 to 10.3 years between 2010 and 2012 and was then stable through 2015 with the consistent presence of fish = 15 years of age. The von Bertalanffy growth parameters of Arctic Char from Tatik Lake were L∞= 703, K= 0.42, and t0= 2.61, with no statistically significant difference between sexes. The mean length of fish 9 to 12 years of age increased beginning in 2008 and continued through 2015. Over the time-series, mean length and weight, and length-atage followed a quasi-cyclic pattern. Condition factor remained relatively high (K = 1.2) and stable from 2008 to 2015, which suggests feeding opportunities were favorable for growth during this period. The annual mortality rate between 2011 and 2015 was stable (~ 30%). Where comparisons were possible, some similarities were observed between the biological data collected from the 1992-2015 monitoring, and data collected from this same fishery in 1978 and 1987. Collectively, the catch and monitoring data through 2015 indicate that the Kuujjua River population is not experiencing overfishing and the current stock status is healthy. [ABSTRACT FROM AUTHOR]

Evolutionary explanations for mammalian sociality typically center on inclusive-fitness benefits of associating and cooperating with close kin, or close maternal kin as in some whale societies, including killer and sperm whales. Their matrilineal structure has strongly influenced the thinking about social structure in less well-studied cetaceans, including beluga whales. In a cross-sectional study of group structure and kinship we found that belugas formed a limited number of distinct group types, consistently observed across populations and habitats. Certain behaviours were associated with group type, but group membership was often dynamic. MtDNA-microsatellite profiling combined with relatedness and network analysis revealed, contrary to predictions, that most social groupings were not predominantly organized around close maternal relatives. They comprised both kin and non-kin, many group members were paternal rather than maternal relatives, and unrelated adult males often traveled together. The evolutionary mechanisms that shape beluga societies are likely complex; fitness benefits may be achieved through reciprocity, mutualism and kin selection. At the largest scales these societies are communities comprising all ages and both sexes where multiple social learning pathways involving kin and non-kin can foster the emergence of cultures. We explore the implications of these findings for species management and the evolution of menopause. [ABSTRACT FROM AUTHOR]