Freshwater seal

The only exclusively freshwater seal species is the Baikal seal, locally named {{Transliteration|ru|nerpa}} ({{wikt-lang|ru|нерпа}}).{{cite book|author1=Edward C M Parsons|author2=Parsons, ECM|author3=Bauer, A|title=An Introduction to Marine Mammal Biology and Conservation|url=https://books.google.com/books?id=XbyxI-d5idcC&pg=PA118|year=2013|publisher=Jones & Bartlett|isbn=978-0-7637-8344-0|page=118}} The Baikal seal has inhabited Lake Baikal for roughly two million years, the closest relative to it being the Arctic ringed seal whence it has likely descended.Palo, Jukka U.; Väinölä, Risto (2006). "The enigma of the landlocked Baikal and Caspian seals addressed through phylogeny of phocine mitochondrial sequences". Biological Journal of the Linnean Society. 88 (1): 61–72. doi:10.1111/j.1095-8312.2006.00607.x. The manner by which the baikal seal reached Lake Baikal is still not fully understood, theories include their entrance into the lake via travel up the Yenisei River or perhaps via large lakes which existed in Siberia during the Pleistocene.

While the Baikal Seal is the only unique species of pinniped to live in a purely freshwater environment for the duration of their lives, various species of typically saltwater seals may occasionally frequent freshwater environments or include isolated populations in near coastal freshwater lakes.

File:Ладожская нерпа.jpg

Two subspecies of ringed seals live solely in freshwater lakes. The Ladoga seal inhabits Lake Ladoga in the Leningrad Oblast and Republic of Karelia. The seals became isolated in Lake Ladoga from the Baltic ringed seal (Pusa hispida botnica) as early as 8,800 BP due to the gradual isostatic rebound of the region following the end of the Weichselian Glaciation.Davydova, Natalia N.; et al. (1996). "Late- and postglacial history of lakes of the Karelian Isthmus". Hydrobiologia. 322 (1–3): 199–204. doi:10.1007/BF00031828. S2CID 9631019. Modern populations of the Ladoga seal only stand at around 2,000 to 3,000 individuals, a significant decline from the estimated 20,000 seals which inhabited Lake Ladoga before hunting decreased the population.Verevkin M.V. (2003) Rezultatyi aviaucheta kolchatoy nerpyi na Ladozhskom ozere Dinamika populyatsiy ohotnichih zhivotnyih severnoy Evropyi, materialyi III Mezhdunarodnogo simpoziuma, 16–20 July 2002, Sortavala, Republic of Karelia, Russia. - Petrozavodsk. – 2003: 202-204.Chapskiy K.K. (1932) Ladozhskiy tyulen i vozmozhnost ego promyisla. – Otchet dlya Leningradskogo Issledovatelskogo instituta ryibolovstva: 147 – 157.

The Saimaa ringed seal is closely related to the Ladoga ringed seal, the populations likely became isolated from the Baltic ringed seal around the same time. The Saimaa ringed seal lives solely within Saimaa, a large freshwater lake in the regions of South Savo, South Karelia, and North Karelia in Finland. Current estimates place the size of the population at between 420 and 430 individuals, an increase from the roughly 100 to 150 individuals present in 1983."Few Saimaa seal pups lost this past winter". yle.fi. Retrieved 29 November 2021.Partio, Elina (2013-09-13). "Saimaannorpan kanta kasvussa".

Harbor seals (common seals) are also known to enter estuaries and freshwater rivers in pursuit of their prey.[http://www.pressherald.com/2011/06/29/harbor-seal-pups-swim-60-miles-inland_2011-06-29/ "Harbor seal pups swim 60 miles inland in Maine"], Portland Press-Herald, June 29, 2011. In addition a unique subspecies in Quebec and an isolated population of harbor seals in Alaska are known to inhabit freshwater lakes for the duration of the year. They are also known to frequently migrate to the Western Arctic. The Ungava seal (Phoca vitulina mellonae) is a subspecies of the harbor seal which lives solely within the landlocked and fresh water environment of Lacs des Loups Marins, Petit Lac de Loups Marins, and Lac Bourdel in northern Quebec.{{Cite journal |last=Smith |first=Richard J. |author2=Cox, Tara M. |author3=Westgate, Andrew J. |title=Movements of Harbor Seals (Phoca Vitulina Mellonae) in Lacs des Loups Marins, Quebec |date=17 Jan 2006 |url=http://www3.interscience.wiley.com/journal/118622756/abstract?CRETRY=1&SRETRY=0 |url-status=dead |journal=Marine Mammal Science |volume=22 |issue=2 |pages=485 |doi=10.1111/j.1748-7692.2006.00024.x |bibcode=2006MMamS..22..480S |archive-url=https://archive.today/20130105230321/http://www3.interscience.wiley.com/journal/118622756/abstract?CRETRY=1&SRETRY=0 |archive-date=5 January 2013 |accessdate=16 July 2010|url-access=subscription }} This subspecies of harbor seal is currently listed as endangered by the IUCN due to the current population being as low as only 100 to 300 individuals.Enns, Amie; Kraus, Dan; Hebb, Andrea (4 June 2020). "Ours to Save: The distribution, status & conservation needs of Canada's endemic species" (PDF). NatureServe Canada and Nature Conservancy of Canada. Retrieved 2 February 2023.{{Cite web |last=Turpin |first=Ben |author-link= |date=23 April 2008 |title=Freshwater seals of Iliamna Lake photographed |url=http://scottdickerson.com/blog/2008/freshwater-seals-of-iliamna-lake-photographed/comment-page-1/#comment-297 |accessdate=16 July 2010 |work=Scott Dickerson Blog |publisher=Scott Dickerson photography |archive-date=16 July 2011 |archive-url=https://web.archive.org/web/20110716021229/http://scottdickerson.com/blog/2008/freshwater-seals-of-iliamna-lake-photographed/comment-page-1/#comment-297 |url-status=dead }}

File:Iliamna Lake by Sentinel-2 (Original 10m Res).jpg Earth observation satellite]]

Another freshwater isolated population of harbor seals exists in Iliamna Lake, Alaska.{{cite journal |last1=Hauser |first1=Donna D. W. |last2=Allen |first2=Christopher S. |last3=Rich |first3=Harry B. |last4=Quinn |first4=Thomas P. |title=Resident Harbor Seals (Phoca vitulina) in Iliamna Lake, Alaska: Summer Diet and Partial Consumption of Adult Sockeye Salmon (Oncorhynchus nerka) |journal=Aquatic Mammals |date=2008 |volume=34 |issue=3 |pages=303–309 |doi=10.1578/AM.34.3.2008.303}} These seals represent an isolated population of the Pacific Harbor Seal (Phoca vitulina richardsi), the survival of this population is due to the existence of a number of islands within the lake for the seals to pup on, away from potential predators on the shoreline of the lake.Burns, J., J. Van Lanen, D. Withrow, D. Holen, T. Askoak, H. Aderman, G. O’Corry-Crowe, G. Zimpelman, and B. Jones. 2013. Integrating local traditional knowledge and subsistence use patterns with aerial surveys to improve scientific and local understanding of the Iliamna Lake seals. Report to the North Pacific Research Board Final Report 1116. 189 p. The diet of these seals is primarily composed of Salmonids in the summer with the diet of these seals remaining obscure throughout the remainder of the year.Hauser, D. D. W., C. S. Allen, H. B. Rich, Jr., and T. P. Quinn. 2008. Resident Harbor Seals (Phoca vitulina) in Iliamna Lake, Alaska: Summer Diet and Partial Consumption of Adult Sockeye Salmon (Oncorhynchus nerka). Aquatic Mammals 34:303-309. This population has been recorded at around 400 individuals, though following particularly harsh winters in the 1970s, the population is thought to have dropped to as low as only 50 individuals.Mathisen, O. A., and T. C. Kline. 1992. Harbor seals in Iliamna Lake, Bristol Bay, Alaska Juneau Center for Fisheries and Ocean Sciences, University of Alaska Fairbanks Final Report on Aerial Census in 1991. 9 p. The harbor seals of Iliamna Lake were first noted in historic records in the 1800s, thus they have been present there for a minimum of 200 years. The oldest possible date for their arrival in the lake is thought to be approximately 5,000 BP, prior to this the lake would have been less accessible due to the outflowing river flowing steeply down a glacial moraine. Any date older than between 12,600 and 16,000 BP can be entirely precluded because of the existence of glacial ice where the lake now exists.Boveng, P. L., S. P. Dahle, J. K. Jansen, J. M. London, B. L. Taylor, and D. E. Withrow. 2016. Scientific evaluation of the distinctness of harbor seals (Phoca vitulina) in Iliamna Lake. Report from the NOAA Alaska Fisheries Science Center to the NOAA Fisheries Alaska Region Office. Marine Mammal Laboratory, Alaska Fisheries Science Center, 7600 Sand Point Way NE, Seattle, WA 98115, U.S.A. 56 pp.

California sea lions and Steller sea lions can also live in fresh water for extended periods of time, such as near the Bonneville Dam, nearly {{convert|150|mi|km|order=flip}} up the Columbia River and at the bottom of the Willamette Falls on the Willamette River.{{cite web |title=Columbia River Sea Lion Management: Restoring balance between predators and salmon |publisher=Washington Department of Fish & Wildlife |url=http://wdfw.wa.gov/conservation/sealions/ |access-date=23 May 2012 |archive-url=https://web.archive.org/web/20171021212903/http://wdfw.wa.gov/conservation/sealions/ |archive-date=21 October 2017 |url-status=dead |df=dmy-all }}{{Cite web |last=Harrison |first=John |date=May 29, 2018 |title=Sea Lions in the Willamette |url=https://www.nwcouncil.org/news/sea-lions-willamette/ |access-date=July 24, 2023 |website=Northwest Power and Conservation Council}} In 2004, a healthy sea lion was found sitting on a road in Merced County, California, almost a hundred miles upstream from the San Francisco Bay and half a mile from the San Joaquin River.{{cite news |last=Kay |first=Jane |title=When good fishing trips go bad: Sea lion swims the Delta – lands on Merced County farm road |newspaper=San Francisco Chronicle |date=10 February 2012 |url=http://www.sfgate.com/default/article/When-good-fishing-trips-go-bad-Sea-lion-swims-2798458.php |access-date=3 July 2012}}

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Category:Pinnipeds

Category:Freshwater animals