1
|
Mikkelsen L, Kovacs KM, Blanchet MA, Brodin G, Lydersen C. Interannual site fidelity by Svalbard walruses. Sci Rep 2024; 14:15822. [PMID: 38982120 PMCID: PMC11233647 DOI: 10.1038/s41598-024-66370-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/01/2024] [Indexed: 07/11/2024] Open
Abstract
The Arctic is experiencing rapid reductions in sea ice, affecting all ice-dependant species. In the present study we examine interannual seasonal movements and habitat use in relation to sea ice coverage for one of the Arctic endemic marine mammals. We tagged 40 male walruses (Odobenus rosmarus) in the Svalbard Archipelago with custom-designed tusk-mounted GPS loggers. Twelve of these animals provided tracks that lasted 1-6 years. Eleven of the walruses displayed clear seasonal migratory behaviour between summer foraging areas and winter breeding areas. Individuals showed high inter-individual variation, but clear site fidelity, using the same areas in consecutive years despite variable sea ice conditions. The walruses swam 5225-10,406 km per year and travelled remarkably similar distances between years on an individual basis. The phenology of migration was not impacted by sea ice concentrations or daylight length but was consistent at the individual level, suggesting endogenous drivers. Sea ice concentrations influenced movement behaviour with animals showing more tortuous paths when in areas with heavy sea ice, possibly searching for polynyas where females reside. Ongoing climate change is expected to drastically change walrus habitat, and it remains to be seen if walruses will be able to shift from their fixed seasonal migratory routines.
Collapse
Affiliation(s)
- Lonnie Mikkelsen
- Norwegian Polar Institute, Framsenteret, Hjalmar Johansens Gate 14, 9296, Tromsø, Norway.
| | - Kit M Kovacs
- Norwegian Polar Institute, Framsenteret, Hjalmar Johansens Gate 14, 9296, Tromsø, Norway
| | - Marie-Anne Blanchet
- Norwegian Polar Institute, Framsenteret, Hjalmar Johansens Gate 14, 9296, Tromsø, Norway
| | - Gary Brodin
- Pathtrack Ltd, Unit 1, Chevin Mill, Leeds Road, Otley, LS21 1BT, UK
| | - Christian Lydersen
- Norwegian Polar Institute, Framsenteret, Hjalmar Johansens Gate 14, 9296, Tromsø, Norway
| |
Collapse
|
2
|
Mills KK, Hildebrandt KPB, Everson KM, Horstmann L, Misarti N, Olson LE. Ancient DNA indicates a century of overhunting did not reduce genetic diversity in Pacific Walruses (Odobenus rosmarus divergens). Sci Rep 2024; 14:8257. [PMID: 38589385 PMCID: PMC11001934 DOI: 10.1038/s41598-024-57414-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 03/18/2024] [Indexed: 04/10/2024] Open
Abstract
Pacific Walruses (Odobenus rosmarus divergens [Illiger 1815]) are gregarious marine mammals considered to be sentinels of the Arctic because of their dependence on sea ice for feeding, molting, and parturition. Like many other marine mammal species, their population sizes were decimated by historical overhunting in the nineteenth and twentieth centuries. Although they have since been protected from nearly all commercial hunting pressure, they now face rapidly accelerating habitat loss as global warming reduces the extent of summer sea ice in the Arctic. To investigate how genetic variation was impacted by overhunting, we obtained mitochondrial DNA sequences from historic Pacific Walrus samples in Alaska that predate the period of overhunting, as well as from extant populations. We found that genetic variation was unchanged over this period, suggesting Pacific Walruses are resilient to genetic attrition in response to reduced population size, and that this may be related to their high vagility and lack of population structure. Although Pacific Walruses will almost certainly continue to decline in number as the planet warms and summer sea ice is further reduced, they may be less susceptible to the ratcheting effects of inbreeding that typically accompany shrinking populations.
Collapse
Affiliation(s)
- Kendall K Mills
- Department of Mammalogy, University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA.
- Department of Biology and Wildlife, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA.
| | - Kyndall P B Hildebrandt
- Department of Mammalogy, University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA
| | - Kathryn M Everson
- Department of Mammalogy, University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA
- Department of Integrative Biology, Oregon State University, 2701 SW Campus Way, Corvallis, OR, 97331, USA
| | - Lara Horstmann
- College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Nicole Misarti
- Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks, AK, 99775, USA
| | - Link E Olson
- Department of Mammalogy, University of Alaska Museum, 1962 Yukon Drive, Fairbanks, AK, 99775, USA
| |
Collapse
|
3
|
Ruiz-Puerta EJ, Keighley X, Desjardins SPA, Gotfredsen AB, Pan SE, Star B, Boessenkool S, Barrett JH, McCarthy ML, Andersen LW, Born EW, Howse LR, Szpak P, Pálsson S, Malmquist HJ, Rufolo S, Jordan PD, Olsen MT. Holocene deglaciation drove rapid genetic diversification of Atlantic walrus. Proc Biol Sci 2023; 290:20231349. [PMID: 37752842 PMCID: PMC10523089 DOI: 10.1098/rspb.2023.1349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 08/27/2023] [Indexed: 09/28/2023] Open
Abstract
Rapid global warming is severely impacting Arctic ecosystems and is predicted to transform the abundance, distribution and genetic diversity of Arctic species, though these linkages are poorly understood. We address this gap in knowledge using palaeogenomics to examine how earlier periods of global warming influenced the genetic diversity of Atlantic walrus (Odobenus rosmarus rosmarus), a species closely associated with sea ice and shallow-water habitats. We analysed 82 ancient and historical Atlantic walrus mitochondrial genomes (mitogenomes), including now-extinct populations in Iceland and the Canadian Maritimes, to reconstruct the Atlantic walrus' response to Arctic deglaciation. Our results demonstrate that the phylogeography and genetic diversity of Atlantic walrus populations was initially shaped by the last glacial maximum (LGM), surviving in distinct glacial refugia, and subsequently expanding rapidly in multiple migration waves during the late Pleistocene and early Holocene. The timing of diversification and establishment of distinct populations corresponds closely with the chronology of the glacial retreat, pointing to a strong link between walrus phylogeography and sea ice. Our results indicate that accelerated ice loss in the modern Arctic may trigger further dispersal events, likely increasing the connectivity of northern stocks while isolating more southerly stocks putatively caught in small pockets of suitable habitat.
Collapse
Affiliation(s)
- Emily J. Ruiz-Puerta
- Section for Molecular Ecology and Evolution, Globe Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Øster Farimagsgade 5-7, 1353 Copenhagen Kobenhavn, Denmark
- Arctic Centre & Groningen Institute of Archaeology, Faculty of Arts, University of Groningen, PO Box 716, 9700 AS Groningen, The Netherlands
| | - Xénia Keighley
- Section for Molecular Ecology and Evolution, Globe Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Øster Farimagsgade 5-7, 1353 Copenhagen Kobenhavn, Denmark
- The Bureau of Meteorology, The Treasury Building, Parkes Place West, Parkes, Australian Capital Territory 2600, Australia
| | - Sean P. A. Desjardins
- Arctic Centre & Groningen Institute of Archaeology, Faculty of Arts, University of Groningen, PO Box 716, 9700 AS Groningen, The Netherlands
- Palaeobiology Section, Canadian Museum of Nature, PO Box 3443, Station D, Ottawa, Ontario, Canada K1P 6P4
| | - Anne Birgitte Gotfredsen
- Section for GeoGenetics, Globe Institute, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen Kobenhavn, Denmark
| | - Shyong En Pan
- Palaeobiology Section, Canadian Museum of Nature, PO Box 3443, Station D, Ottawa, Ontario, Canada K1P 6P4
| | - Bastiaan Star
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Blindernveien 31, 0371 Oslo, Norway
| | - Sanne Boessenkool
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Blindernveien 31, 0371 Oslo, Norway
| | - James H. Barrett
- Department of Archaeology and Cultural History, NTNU University Museum, 7491 Trondheim, Norway
- McDonald Institute for Archaeological Research, Department of Archaeology, University of Cambridge, Downing Street, Cambridge CB2 3ER, UK
| | - Morgan L. McCarthy
- Section for Molecular Ecology and Evolution, Globe Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Øster Farimagsgade 5-7, 1353 Copenhagen Kobenhavn, Denmark
| | - Liselotte W. Andersen
- Department of Ecoscience, Aarhus University, CF Møllers Allé 4-8, build. 1110, 8000 Aarhus C, Denmark
| | - Erik W. Born
- Greenland Institute of Natural Resources, PO Box 570, 3900 Nuuk, Greenland
| | - Lesley R. Howse
- Archaeology Centre, University of Toronto, 19 Ursula Franklin Street, Toronto, Ontario Canada M5S 2S2
| | - Paul Szpak
- Department of Anthropology, Trent University, 1600 West Bank Drive, Peterborough, Ontario, Canada K9L 0G2
| | - Snæbjörn Pálsson
- Faculty of Life and Environmental Sciences, University of Iceland, Askja, Sturlugata 7, 101 Reykjavik, Iceland
| | - Hilmar J. Malmquist
- Icelandic Museum of Natural History, Suðurlandsbraut 24, 108 Reykjavík, Iceland
| | - Scott Rufolo
- Palaeobiology Section, Canadian Museum of Nature, PO Box 3443, Station D, Ottawa, Ontario, Canada K1P 6P4
| | - Peter D. Jordan
- Department of Archaeology and Ancient History, Lund University, Helgonavägen 3, 223 62 Lund, Sweden
- Global Station for Indigenous Studies and Cultural Diversity (GSI), GI-CoRE, HokkaidoUniversity, Japan
| | - Morten Tange Olsen
- Section for Molecular Ecology and Evolution, Globe Institute, Faculty of Health and Medical Sciences, University of Copenhagen, Øster Farimagsgade 5-7, 1353 Copenhagen Kobenhavn, Denmark
- Natural History Museum of Denmark, University of Copenhagen, Denmark
| |
Collapse
|
4
|
Zoologist, traveller and explorer: celebrating the 60th anniversary of Alexei Vladimirovich Abramov. RUSSIAN JOURNAL OF THERIOLOGY 2022. [DOI: 10.15298/rusjtheriol.21.2.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
5
|
McLaughlin WNF, Boatman CJ, Davis EB, Hopkins SSB. Total Dental Occlusal Area as a Feeding Constraint Feature in Extant Walruses (Odobenus rosmarus), and Implications for the Evolution of Molluscivory in Odobenidae. J MAMM EVOL 2022. [DOI: 10.1007/s10914-022-09603-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
6
|
New migration and distribution patterns of Atlantic walruses ( Odobenus rosmarus rosmarus) around Nunavik (Québec, Canada) identified using Inuit Knowledge. Polar Biol 2021; 44:1833-1845. [PMID: 34720377 PMCID: PMC8550009 DOI: 10.1007/s00300-021-02920-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 12/04/2022]
Abstract
Environmental changes are affecting the Arctic at an unprecedented rate, but limited scientific knowledge exists on their impacts on species such as walruses (Odobenus rosmarus). Inuit Traditional and Local Ecological Knowledge (Inuit TEK/LEK) held by Inuit walrus harvesters could shed light on walrus ecology and related environmental changes. Our main objective was to study spatial and temporal changes in Atlantic walrus (Odobenus rosmarus rosmarus) distribution in Nunavik (northern Québec, Canada) using Inuit TEK/LEK. To do so, we documented the knowledge and observations of 33 local hunters and Elders as part of a larger project on Atlantic walruses in Nunavik. We first gathered information on changes in Inuit land use patterns and harvesting practices through time and space, which was a crucial step to avoid potential biases in interpreting local observations on walrus distribution. We found that walrus hunters are now covering smaller hunting areas over shorter time periods, reducing in space and time their observations of Atlantic walruses around Nunavik. While clearly taking these limitations into account, we learned from interviews that some areas abandoned by Atlantic walruses in the past were now being re-occupied. Importantly, Atlantic walruses, which migrate following the melting ice, are now traveling along the eastern coast of Nunavik one month earlier, suggesting that Atlantic walrus migration has changed due to variations in sea-ice coverage around Nunavik. Our study not only highlighted important changes in Atlantic walrus distribution and migration in Nunavik, but also sheds light on the importance of documenting temporal and spatial changes in Inuit land use patterns and harvesting practices to understand the ecology of Arctic species using Inuit Knowledge.
Collapse
|
7
|
Beatty WS, Lemons PR, Sethi SA, Everett JP, Lewis CJ, Lynn RJ, Cook GM, Garlich-Miller JL, Wenburg JK. Panmixia in a sea ice-associated marine mammal: evaluating genetic structure of the Pacific walrus (Odobenus rosmarus divergens) at multiple spatial scales. J Mammal 2020. [DOI: 10.1093/jmammal/gyaa050] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AbstractThe kin structure of a species at relatively fine spatial scales impacts broad-scale patterns in genetic structure at the population level. However, kin structure rarely has been elucidated for migratory marine mammals. The Pacific walrus (Odobenus rosmarus divergens) exhibits migratory behavior linked to seasonal patterns in sea ice dynamics. Consequently, information on the spatial genetic structure of the subspecies, including kin structure, could aid wildlife managers in designing future studies to evaluate the impacts of sea ice loss on the subspecies. We sampled 8,303 individual walruses over a 5-year period and used 114 single-nucleotide polymorphisms to examine both broad-scale patterns in genetic structure and fine-scale patterns in relatedness. We did not detect any evidence of genetic structure at broad spatial scales, with low FST values (≤ 0.001) across all pairs of putative aggregations. To evaluate kin structure at fine spatial scales, we defined a walrus group as a cluster of resting individuals that were less than one walrus body length apart. We found weak evidence of kin structure at fine spatial scales, with 3.72% of groups exhibiting mean relatedness values greater than expected by chance, and a significantly higher overall observed mean value of relatedness within groups than expected by chance. Thus, the high spatiotemporal variation in the distribution of resources in the Pacific Arctic environment likely has favored a gregarious social system in Pacific walruses, with unrelated animals forming temporary associations.
Collapse
Affiliation(s)
- William S Beatty
- U.S. Fish and Wildlife Service, Marine Mammals Management, Anchorage, AK, USA
| | - Patrick R Lemons
- U.S. Fish and Wildlife Service, Marine Mammals Management, Anchorage, AK, USA
| | - Suresh A Sethi
- U.S. Geological Survey, New York Cooperative Fish and Wildlife Research Unit, Ithaca, NY, USA
| | - Jason P Everett
- U.S. Fish and Wildlife Service, Conservation Genetics Laboratory, Anchorage, AK, USA
| | - Cara J Lewis
- U.S. Fish and Wildlife Service, Conservation Genetics Laboratory, Anchorage, AK, USA
| | - Robert J Lynn
- U.S. Fish and Wildlife Service, Marine Mammals Management, Anchorage, AK, USA
| | - Geoffrey M Cook
- U.S. Fish and Wildlife Service, Conservation Genetics Laboratory, Anchorage, AK, USA
| | | | - John K Wenburg
- U.S. Fish and Wildlife Service, Conservation Genetics Laboratory, Anchorage, AK, USA
| |
Collapse
|
8
|
Keighley X, Pálsson S, Einarsson BF, Petersen A, Fernández-Coll M, Jordan P, Olsen MT, Malmquist HJ. Disappearance of Icelandic Walruses Coincided with Norse Settlement. Mol Biol Evol 2020; 36:2656-2667. [PMID: 31513267 PMCID: PMC6878957 DOI: 10.1093/molbev/msz196] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
There is a growing body of evidence demonstrating the impacts of human arrival in new “pristine” environments, including terrestrial habitat alterations and species extinctions. However, the effects of marine resource utilization prior to industrialized whaling, sealing, and fishing have largely remained understudied. The expansion of the Norse across the North Atlantic offers a rare opportunity to study the effects of human arrival and early exploitation of marine resources. Today, there is no local population of walruses on Iceland, however, skeletal remains, place names, and written sources suggest that walruses existed, and were hunted by the Norse during the Settlement and Commonwealth periods (870–1262 AD). This study investigates the timing, geographic distribution, and genetic identity of walruses in Iceland by combining historical information, place names, radiocarbon dating, and genomic analyses. The results support a genetically distinct, local population of walruses that went extinct shortly after Norse settlement. The high value of walrus products such as ivory on international markets likely led to intense hunting pressure, which—potentially exacerbated by a warming climate and volcanism—resulted in the extinction of walrus on Iceland. We show that commercial hunting, economic incentives, and trade networks as early as the Viking Age were of sufficient scale and intensity to result in significant, irreversible ecological impacts on the marine environment. This is to one of the earliest examples of local extinction of a marine species following human arrival, during the very beginning of commercial marine exploitation.
Collapse
Affiliation(s)
- Xénia Keighley
- Section for Evolutionary Genomics, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark.,Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark.,Arctic Centre and Groningen Institute of Archaeology, University of Groningen, Groningen, The Netherlands
| | - Snæbjörn Pálsson
- Faculty of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland
| | | | | | - Meritxell Fernández-Coll
- Faculty of Life and Environmental Sciences, University of Iceland, Reykjavik, Iceland.,Icelandic Museum of Natural History, Reykjavík, Iceland
| | - Peter Jordan
- Arctic Centre and Groningen Institute of Archaeology, University of Groningen, Groningen, The Netherlands
| | - Morten Tange Olsen
- Section for Evolutionary Genomics, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark.,Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark
| | | |
Collapse
|
9
|
Boltunov A, Semenova V, Samsonov D, Boltunov N, Nikiforov V. Persistent organic pollutants in the Pechora Sea walruses. Polar Biol 2019. [DOI: 10.1007/s00300-019-02457-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
10
|
New records of Holocene polar bear and walrus (Carnivora) in the Russian Arctic. RUSSIAN JOURNAL OF THERIOLOGY 2018. [DOI: 10.15298/rusjtheriol.17.2.02] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
11
|
Star B, Barrett JH, Gondek AT, Boessenkool S. Ancient DNA reveals the chronology of walrus ivory trade from Norse Greenland. Proc Biol Sci 2018; 285:rspb.2018.0978. [PMID: 30089624 PMCID: PMC6111184 DOI: 10.1098/rspb.2018.0978] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 07/12/2018] [Indexed: 01/27/2023] Open
Abstract
The importance of the Atlantic walrus ivory trade for the colonization, peak, and collapse of the medieval Norse colonies on Greenland has been extensively debated. Nevertheless, no studies have directly traced medieval European ivory back to distinct Arctic populations of walrus. Analysing the entire mitogenomes of 37 archaeological specimens from Europe, Svalbard, and Greenland, we here discover that Atlantic walrus comprises two monophyletic mitochondrial (MT) clades, which diverged between 23 400 and 251 120 years ago. Our improved genomic resolution allows us to reinterpret the geographical distribution of partial MT data from 306 modern and nineteenth-century specimens, finding that one of these clades was exclusively accessible to Greenlanders. With this discovery, we ascertain the biological origin of 23 archaeological specimens from Europe (most dated between 900 and 1400 CE). These results reveal a significant shift in trade from an early, predominantly eastern source towards a near exclusive representation of Greenland ivory. Our study provides empirical evidence for how this remote Arctic resource was progressively integrated into a medieval pan-European trade network, contributing to both the resilience and vulnerability of Norse Greenland society.
Collapse
Affiliation(s)
- Bastiaan Star
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway
| | - James H Barrett
- McDonald Institute for Archaeological Research, Department of Archaeology, University of Cambridge, Downing Street, Cambridge CB2 3ER, UK
| | - Agata T Gondek
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway
| | - Sanne Boessenkool
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, PO Box 1066, Blindern, 0316 Oslo, Norway
| |
Collapse
|
12
|
Andersen LW, Jacobsen MW, Lydersen C, Semenova V, Boltunov A, Born EW, Wiig Ø, Kovacs KM. Walruses (Odobenus rosmarus rosmarus) in the Pechora Sea in the context of contemporary population structure of Northeast Atlantic walruses. Biol J Linn Soc Lond 2017. [DOI: 10.1093/biolinnean/blx093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
13
|
Shitova MV, Kochnev AA, Dolnikova OG, Kryukova NV, Malinina TV, Pereverzev AA. Genetic diversity of the Pacific walrus (Odobenus rosmarus divergens) in the western part of the Chukchi Sea. RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417020107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
14
|
Martinez-Levasseur LM, Furgal CM, Hammill MO, Burness G. Towards a Better Understanding of the Effects of UV on Atlantic Walruses, Odobenus rosmarus rosmarus: A Study Combining Histological Data with Local Ecological Knowledge. PLoS One 2016; 11:e0152122. [PMID: 27049757 PMCID: PMC4822789 DOI: 10.1371/journal.pone.0152122] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 03/09/2016] [Indexed: 12/21/2022] Open
Abstract
Walruses, Odobenus rosmarus, play a key role in the Arctic ecosystem, including northern Indigenous communities, which are reliant upon walruses for aspects of their diet and culture. However, walruses face varied environmental threats including rising sea-water temperatures and decreasing ice cover. An underappreciated threat may be the large amount of solar ultraviolet radiation (UV) that continues to reach the Arctic as a result of ozone loss. UV has been shown to negatively affect whales. Like whales, walrus skin is unprotected by fur, but in contrast, walruses spend long periods of time hauled-out on land. In this study, we combined the results of histological analyses of skin sections from five Atlantic walruses, Odobenus rosmarus rosmarus, collected in Nunavik (Northern Quebec, Canada) with qualitative data obtained through the interviews of 33 local walrus hunters and Inuit Elders. Histological analyses allowed us to explore UV-induced cellular lesions and interviews with experienced walrus hunters and Elders helped us to study the incidences and temporal changes of UV-induced gross lesions in walruses. At the microscopic scale, we detected a range of skin abnormalities consistent with UV damage. However, currently such UV effects do not seem to be widely observed at the whole-animal level (i.e., absence of skin blistering, erythema, eye cataract) by individuals interviewed. Although walruses may experience skin damage under normal everyday UV exposure, the long-term data from local walrus hunters and Inuit Elders did not report a relation between the increased sun radiation secondary to ozone loss and walrus health.
Collapse
Affiliation(s)
- Laura M. Martinez-Levasseur
- Department of Biology, Trent University, Peterborough, Ontario, Canada
- Department of Indigenous Studies, Trent University, Peterborough, Ontario, Canada
- * E-mail: (GB); (LMML)
| | - Chris M. Furgal
- Department of Indigenous Studies, Trent University, Peterborough, Ontario, Canada
- Environmental Resource Studies and Sciences, Trent University, Peterborough, Ontario, Canada
| | - Mike O. Hammill
- Maurice Lamontagne Institute, Fisheries and Oceans Canada, Mont-Joli, Quebec, Canada
| | - Gary Burness
- Department of Biology, Trent University, Peterborough, Ontario, Canada
- * E-mail: (GB); (LMML)
| |
Collapse
|
15
|
McClain CR, Balk MA, Benfield MC, Branch TA, Chen C, Cosgrove J, Dove ADM, Gaskins L, Helm RR, Hochberg FG, Lee FB, Marshall A, McMurray SE, Schanche C, Stone SN, Thaler AD. Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ 2015; 3:e715. [PMID: 25649000 PMCID: PMC4304853 DOI: 10.7717/peerj.715] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 12/10/2014] [Indexed: 11/20/2022] Open
Abstract
What are the greatest sizes that the largest marine megafauna obtain? This is a simple question with a difficult and complex answer. Many of the largest-sized species occur in the world’s oceans. For many of these, rarity, remoteness, and quite simply the logistics of measuring these giants has made obtaining accurate size measurements difficult. Inaccurate reports of maximum sizes run rampant through the scientific literature and popular media. Moreover, how intraspecific variation in the body sizes of these animals relates to sex, population structure, the environment, and interactions with humans remains underappreciated. Here, we review and analyze body size for 25 ocean giants ranging across the animal kingdom. For each taxon we document body size for the largest known marine species of several clades. We also analyze intraspecific variation and identify the largest known individuals for each species. Where data allows, we analyze spatial and temporal intraspecific size variation. We also provide allometric scaling equations between different size measurements as resources to other researchers. In some cases, the lack of data prevents us from fully examining these topics and instead we specifically highlight these deficiencies and the barriers that exist for data collection. Overall, we found considerable variability in intraspecific size distributions from strongly left- to strongly right-skewed. We provide several allometric equations that allow for estimation of total lengths and weights from more easily obtained measurements. In several cases, we also quantify considerable geographic variation and decreases in size likely attributed to humans.
Collapse
Affiliation(s)
- Craig R McClain
- National Evolutionary Synthesis Center , Durham, NC , USA ; Department of Biology, Duke University , Durham, NC , USA
| | - Meghan A Balk
- Department of Biology, University of New Mexico , Albuquerque, NM , USA
| | - Mark C Benfield
- Department of Oceanography and Coastal Sciences, Louisiana State University , Baton Rouge, LA , USA
| | - Trevor A Branch
- School of Aquatic & Fishery Sciences, University of Washington , Seattle, WA , USA
| | - Catherine Chen
- Department of Biology, Duke University , Durham, NC , USA
| | - James Cosgrove
- Natural History Section, Royal British Columbia Museum , Victoria, BC , Canada
| | | | - Leo Gaskins
- Department of Biology, Duke University , Durham, NC , USA
| | - Rebecca R Helm
- Department of Ecology and Evolutionary Biology, Brown University , Providence, RI , USA
| | - Frederick G Hochberg
- Department of Invertebrate Zoology, Santa Barbara Museum of Natural History , Santa Barbara, CA , USA
| | - Frank B Lee
- Department of Biology, Duke University , Durham, NC , USA
| | | | - Steven E McMurray
- Department of Biology and Marine Biology, University of North Carolina Wilmington , Wilmington, NC , USA
| | | | - Shane N Stone
- Department of Biology, Duke University , Durham, NC , USA
| | - Andrew D Thaler
- Blackbeard Biologic: Science and Environmental Advisors , Vallejo, CA , USA
| |
Collapse
|
16
|
Assessment of the extirpated Maritimes walrus using morphological and ancient DNA analysis. PLoS One 2014; 9:e99569. [PMID: 24924490 PMCID: PMC4055739 DOI: 10.1371/journal.pone.0099569] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 05/02/2014] [Indexed: 11/20/2022] Open
Abstract
Species biogeography is a result of complex events and factors associated with climate change, ecological interactions, anthropogenic impacts, physical geography, and evolution. To understand the contemporary biogeography of a species, it is necessary to understand its history. Specimens from areas of localized extinction are important, as extirpation of species from these areas may represent the loss of unique adaptations and a distinctive evolutionary trajectory. The walrus (Odobenus rosmarus) has a discontinuous circumpolar distribution in the arctic and subarctic that once included the southeastern Canadian Maritimes region. However, exploitation of the Maritimes population during the 16th-18th centuries led to extirpation, and the species has not inhabited areas south of 55°N for ∼250 years. We examined genetic and morphological characteristics of specimens from the Maritimes, Atlantic (O. r. rosmarus) and Pacific (O. r. divergens) populations to test the hypothesis that the first group was distinctive. Analysis of Atlantic and Maritimes specimens indicated that most skull and mandibular measurements were significantly different between the Maritimes and Atlantic groups and discriminant analysis of principal components confirmed them as distinctive groups, with complete isolation of skull features. The Maritimes walrus appear to have been larger animals, with larger and more robust tusks, skulls and mandibles. The mtDNA control region haplotypes identified in Maritimes specimens were unique to the region and a greater average number of nucleotide differences were found between the regions (Atlantic and Maritimes) than within either group. Levels of diversity (h and π) were lower in the Maritimes, consistent with other studies of species at range margins. Our data suggest that the Maritimes walrus was a morphologically and genetically distinctive group that was on a different evolutionary path from other walrus found in the north Atlantic.
Collapse
|
17
|
Pacific walrus (Odobenus rosmarus divergens) resource selection in the Northern Bering Sea. PLoS One 2014; 9:e93035. [PMID: 24717979 PMCID: PMC3981674 DOI: 10.1371/journal.pone.0093035] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/28/2014] [Indexed: 11/19/2022] Open
Abstract
The Pacific walrus is a large benthivore with an annual range extending across the continental shelves of the Bering and Chukchi Seas. We used a discrete choice model to estimate site selection by adult radio-tagged walruses relative to the availability of the caloric biomass of benthic infauna and sea ice concentration in a prominent walrus wintering area in the northern Bering Sea (St. Lawrence Island polynya) in 2006, 2008, and 2009. At least 60% of the total caloric biomass of dominant macroinfauna in the study area was composed of members of the bivalve families Nuculidae, Tellinidae, and Nuculanidae. Model estimates indicated walrus site selection was related most strongly to tellinid bivalve caloric biomass distribution and that walruses selected lower ice concentrations from the mostly high ice concentrations that were available to them (quartiles: 76%, 93%, and 99%). Areas with high average predicted walrus site selection generally coincided with areas of high organic carbon input identified in other studies. Projected decreases in sea ice in the St. Lawrence Island polynya and the potential for a concomitant decline of bivalves in the region could result in a northward shift in the wintering grounds of walruses in the northern Bering Sea.
Collapse
|
18
|
Spatial variation and low diversity in the major histocompatibility complex in walrus (Odobenus rosmarus). Polar Biol 2014. [DOI: 10.1007/s00300-014-1450-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
19
|
Post E, Bhatt US, Bitz CM, Brodie JF, Fulton TL, Hebblewhite M, Kerby J, Kutz SJ, Stirling I, Walker DA. Ecological Consequences of Sea-Ice Decline. Science 2013; 341:519-24. [PMID: 23908231 DOI: 10.1126/science.1235225] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Eric Post
- The Polar Center, and Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Sonsthagen SA, Jay CV, Fischbach AS, Sage GK, Talbot SL. Spatial genetic structure and asymmetrical gene flow within the Pacific walrus. J Mammal 2012. [DOI: 10.1644/11-mamm-a-344.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Abstract
Pacific walruses (Odobenus rosmarus divergens) occupying shelf waters of Pacific Arctic seas migrate during spring and summer from 3 breeding areas in the Bering Sea to form sexually segregated nonbreeding aggregations. We assessed genetic relationships among 2 putative breeding populations and 6 nonbreeding aggregations. Analyses of mitochondrial DNA (mtDNA) control region sequence data suggest that males are distinct among breeding populations (ΦST = 0.051), and between the eastern Chukchi and other nonbreeding aggregations (ΦST = 0.336–0.449). Nonbreeding female aggregations were genetically distinct across marker types (microsatellite FST = 0.019; mtDNA ΦST = 0.313), as was eastern Chukchi and all other nonbreeding aggregations (microsatellite FST = 0.019–0.035; mtDNA ΦST = 0.386–0.389). Gene flow estimates are asymmetrical from St. Lawrence Island into the southeastern Bering breeding population for both sexes. Partitioning of haplotype frequencies among breeding populations suggests that individuals exhibit some degree of philopatry, although weak. High levels of genetic differentiation among eastern Chukchi and all other nonbreeding aggregations, but considerably lower genetic differentiation between breeding populations, suggest that at least 1 genetically distinct breeding population remained unsampled. Limited genetic structure at microsatellite loci between assayed breeding areas can emerge from several processes, including male-mediated gene flow, or population admixture following a decrease in census size (i.e., due to commercial harvest during 1880–1950s) and subsequent recovery. Nevertheless, high levels of genetic diversity in the Pacific walrus, which withstood prolonged decreases in census numbers with little impact on neutral genetic diversity, may reflect resiliency in the face of past environmental challenges.
Collapse
Affiliation(s)
- Sarah A. Sonsthagen
- United States Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - Chadwick V. Jay
- United States Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - Anthony S. Fischbach
- United States Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - George K. Sage
- United States Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| | - Sandra L. Talbot
- United States Geological Survey, Alaska Science Center, 4210 University Drive, Anchorage, AK 99508, USA
| |
Collapse
|
21
|
BERTA A, CHURCHILL M. Pinniped taxonomy: review of currently recognized species and subspecies, and evidence used for their description. Mamm Rev 2011. [DOI: 10.1111/j.1365-2907.2011.00193.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
22
|
Ancient DNA from marine mammals: studying long-lived species over ecological and evolutionary timescales. Ann Anat 2011; 194:112-20. [PMID: 21652193 DOI: 10.1016/j.aanat.2011.04.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 04/14/2011] [Accepted: 04/15/2011] [Indexed: 11/21/2022]
Abstract
Marine mammals have long generation times and broad, difficult to sample distributions, which makes inferring evolutionary and demographic changes using field studies of extant populations challenging. However, molecular analyses from sub-fossil or historical materials of marine mammals such as bone, tooth, baleen, skin, fur, whiskers and scrimshaw using ancient DNA (aDNA) approaches provide an opportunity for investigating such changes over evolutionary and ecological timescales. Here, we review the application of aDNA techniques to the study of marine mammals. Most of the studies have focused on detecting changes in genetic diversity following periods of exploitation and environmental change. To date, these studies have shown that even small sample sizes can provide useful information on historical genetic diversity. Ancient DNA has also been used in investigations of changes in distribution and range of marine mammal species; we review these studies and discuss the limitations of such 'presence only' studies. Combining aDNA data with stable isotopes can provide further insights into changes in ecology and we review past studies and suggest future potential applications. We also discuss studies reconstructing inter- and intra-specific phylogenies from aDNA sequences and discuss how aDNA sequences could be used to estimate mutation rates. Finally, we highlight some of the problems of aDNA studies on marine mammals, such as obtaining sufficient sample sizes and calibrating for the marine reservoir effect when radiocarbon-dating such wide-ranging species.
Collapse
|
23
|
Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear. Proc Natl Acad Sci U S A 2010; 107:5053-7. [PMID: 20194737 DOI: 10.1073/pnas.0914266107] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The polar bear has become the flagship species in the climate-change discussion. However, little is known about how past climate impacted its evolution and persistence, given an extremely poor fossil record. Although it is undisputed from analyses of mitochondrial (mt) DNA that polar bears constitute a lineage within the genetic diversity of brown bears, timing estimates of their divergence have differed considerably. Using next-generation sequencing technology, we have generated a complete, high-quality mt genome from a stratigraphically validated 130,000- to 110,000-year-old polar bear jawbone. In addition, six mt genomes were generated of extant polar bears from Alaska and brown bears from the Admiralty and Baranof islands of the Alexander Archipelago of southeastern Alaska and Kodiak Island. We show that the phylogenetic position of the ancient polar bear lies almost directly at the branching point between polar bears and brown bears, elucidating a unique morphologically and molecularly documented fossil link between living mammal species. Molecular dating and stable isotope analyses also show that by very early in their evolutionary history, polar bears were already inhabitants of the Artic sea ice and had adapted very rapidly to their current and unique ecology at the top of the Arctic marine food chain. As such, polar bears provide an excellent example of evolutionary opportunism within a widespread mammalian lineage.
Collapse
|