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Beluga whales play a critical role in the subsistence economies and cultural heritage of Indigenous communities across the Arctic, yet the effects of Indigenous hunting on beluga whales remain unknown. Here, we integrate paleogenomics, genetic simulations, and stable δ13C and δ15N isotope analysis to investigate 700 y of beluga subsistence hunting in the Mackenzie Delta area of northwestern Canada. Genetic identification of the zooarchaeological remains, which is based on radiocarbon dating, span three time periods (1290 to 1440 CE; 1450 to 1650 CE; 1800 to 1870 CE), indicates shifts across time in the sex ratio of the harvested belugas. The equal number of females and males harvested in 1450 to 1650 CE versus more males harvested in the two other time periods may reflect changes in hunting practices or temporal shifts in beluga availability. We find temporal shifts and sex-based differences in δ13C of the harvested belugas across time, suggesting historical adaptability in the foraging ecology of the whales. We uncovered distinct mitochondrial diversity unique to the Mackenzie Delta belugas, but found no changes in nuclear genomic diversity nor any substructuring across time. Our findings indicate the genomic stability and continuity of the Mackenzie Delta beluga population across the 700 y surveyed, indicating the impact of Inuvialuit subsistence harvests on the genetic diversity of contemporary beluga individuals has been negligible. [ABSTRACT FROM AUTHOR]

In 2000, the International Whaling Commission conducted a global assessment of beluga whales, Delphinapterus leucas. Following this assessment, five beluga stocks were recognized in Russian Far East waters: Western Chukchi-East Siberian Sea, Anadyr Gulf, Shelikhov, Sakhalin-Amur, and Shantar. This paper provides a revised assessment of beluga abundance, distribution, and population structure in the Russian Far East. This region encompasses the Okhotsk Sea, and the coastline of the Chukotka Autonomous Region (CAR), which includes the western Bering, western Chukchi, and eastern East Siberian seas. Published results of genetic analysis are updated with our original unpublished data. Based on information available to date, we propose recognizing seven beluga stocks in the Russian Far East. Five stocks in the Okhotsk Sea: 1) Sakhalin-Amur, 2) Ulbansky, 3) Tugursky, 4) Udskaya, 5) Shelikhov, and two stocks in the CAR: 6) Anadyr, and 7) Bering-Chukchi-Beaufort (BCB). Natural and anthropogenic threats to these stocks are described and include ice entrapment, over-fishing of key prey, live captures for aquaria, bycatch in fisheries, exposure to effluent, and seismic and military activities., Introduction In the Russian Far East, the beluga, Delphinapterus leucas, or white whale, occurs in the Okhotsk Sea and along the coastline of the Chukotka Autonomous Region in the western [...]

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 [...]

During glacial periods, highly mobile species were able to shift their ranges to warmer regions that remained ice-free--so-called "glacial refugia." Glacial refugia often preserved higher levels of genetic diversity than areas that were colonized after the retreat of glaciers. In this study, we examined genetic and vocal variation in R-type ("resident") killer whales, Orcinus orca, from Nemuro Strait in the western North Pacific to test the hypothesis that environmentally stable marine regions may have preserved refugial populations of the killer whale that retained historical genetic and cultural diversity. We found three distinct mtDNA control region haplotypes and stereotyped calls that differed significantly from the repertoire of a population further north off Kamchatka and the adjacent western North Pacific. Therefore, both genetic and cultural evidence suggest that at least some killer whales from Nemuro Strait represent a separate maternal lineage. The control region haplotype diversity for Nemuro Strait is comparable to that for the rest of the North Pacific. The data presented here are consistent with the existence of the southwestern glacial refugium for killer whales in the waters off northern Japan during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

Genetically verified occurrence points were taken from our data and from publications (Neumann I et al. i [51]; Banaszek I et al. i [8]; Hegyeli I et al. i [32]; Melosik I et al. i [48]; Korbut I et al. i [39]). Later, Korbut I et al. i ([39]) argued this assumption and supposed that "hamsters survived in eastern steppe refugia from which they migrated westward through northern European plains or through the southern route around the Carpathians to Central and Western Europe" (Neumann I et al. i [51]; Banaszek I et al. i [7]). Korbut I et al. i also discussed the potential contraction of the hamster distribution during both Saalian Glacial and Eemian interstadial (Korbut I et al. i [39]). The bins of the scale for MIS7-MIS6 correspond to nomenclature suggested by Railsback I et al. i ([59]), MIS5 by Shackleton I et al. i ([67]), and Otvos ([53]) and MIS4 by Scrucca I et al. i ([66]). Moreover, the common hamster started to rapidly colonize some cities in Western Europe (Schmelzer & Millesi [65]; Feoktistova I et al. i [25]; Flamand I et al. i [27]), in Eastern Europe (Canády [13]; Feoktistova I et al. i [24]; Buczek [12]), and Kazakhstan (Feoktistova I et al. i [20]). [Extracted from the article]

The article presents the discussion on Killer whales (Orcinus orca), being the top predators in marine ecosystems. Topics include little direct evidence of sea otter consumption by killer whales, with only one consumption among the attacks; and predation was not considered to play a role in the decline.

The allelic diversity of exon 2 (DQB gene) and exon 3 (DRB gene) of major histocompatibility complex class II was studied for the first time in two species of the landlocked pinnipeds, Baikal (N = 79) and Caspian (N = 32) seals, and these were in compared with the widespread Arctic species, the ringed seal (N = 13). The analysis of the second exon comprising the antigen-binding region revealed high allelic diversity in all three species but the pattern of the diversity was the most specific for the Baikal seal. This species differs from the other two by the smallest number of alleles in the population, yet they have the largest number of alleles per individual and by the maximum similarity of individual genotypes. Presumably, this specificity is a consequence of the spatial and temporal homogeneity of the Lake Baikal environment. Analysis of the third exon encoding the conserved β2-domain showed that the Baikal seal differs by the greatest number of amino acid sequences per individual, while the Caspian seal has the lowest number of variants. A single variant of the β2-domain, the same as in the ringed seal, predominates in the Caspian seal, whereas in the Baikal seal the two other variants predominate. At the same time, three species-specific amino acid sequences were observed among minor variants in the Caspian seal, while only one was found in the Baikal seal. This fact may suggest a longer period of independent evolution in the Caspian seal compared to the Baikal seal., (© The Author(s) 2024. Published by Oxford University Press on behalf of The American Genetic Association. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)