Skip to main content

Advertisement

SpringerLink
Log in

Resource partitioning between Pacific walruses and bearded seals in the Alaska Arctic and sub-Arctic

  • Physiological ecology - original research
  • Published:
Oecologia Aims and scope Submit manuscript

Abstract

Climate-mediated changes in the phenology of Arctic sea ice and primary production may alter benthic food webs that sustain populations of Pacific walruses (Odobenus rosmarus divergens) and bearded seals (Erignathus barbatus). Interspecific resource competition could place an additional strain on ice-associated marine mammals already facing loss of sea ice habitat. Using fatty acid (FA) profiles, FA trophic markers, and FA stable carbon isotope analyses, we found that walruses and bearded seals partitioned food resources in 2009–2011. Interspecific differences in FA profiles were largely driven by variation in non-methylene FAs, which are markers of benthic invertebrate prey taxa, indicating varying consumption of specific benthic prey. We used Bayesian multi-source FA stable isotope mixing models to estimate the proportional contributions of particulate organic matter (POM) from sympagic (ice algal), pelagic, and benthic sources to these apex predators. Proportional contributions of FAs to walruses and bearded seals from benthic POM sources were high [44 (17–67)% and 62 (38–83)%, respectively] relative to other sources of POM. Walruses also obtained considerable contributions of FAs from pelagic POM sources [51 (32–73)%]. Comparison of δ13C values of algal FAs from walruses and bearded seals to those from benthic prey from different feeding groups from the Chukchi and Bering seas revealed that different trophic pathways sustained walruses and bearded seals. Our findings suggest that (1) resource partitioning may mitigate interspecific competition, and (2) climate change impacts on Arctic food webs may elicit species-specific responses in these high trophic level consumers.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  • Abrajano TA, Murphy DE, Fang J, Comet P, Brooks JM (1994) 13C/12C ratios in individual fatty acids of marine mytilids with and without bacterial symbionts. Org Geochem 21:611–617. doi:10.1016/0146-6380(94)90007-8

    Article  CAS  Google Scholar 

  • Ackman RG, Sipos JC (1964) Application of specific response factors in the gas chromatographic analysis of methyl esters of fatty acids with flame ionization detectors. J Am Oil Chem Soc 41:377–378

    Article  CAS  Google Scholar 

  • Arrigo KR (2013) The changing Arctic Ocean. Elem Sci Anthropocene. doi:10.12952/journal.elementa.000010

    Google Scholar 

  • Arrigo KR, Perovich DK, Pickart RS, Brown ZW, van Dijken GL, Lowry KE, Mills MM, Palmer MA, Balch WM, Bahr F, Bates NR, Benitez-Nelson C, Bowler B, Brownlee E, Ehn JK, Frey KE, Garley R, Laney SR, Lubelczyk L, Mathis J, Matsuoka A, Mitchell BG, Moore GW, Ortega-Retuerta E, Pal S, Polashenski CM, Reyolds RA, Schieber B, Sosik HM, Stephens M, Swift JH (2012) Massive phytoplankton blooms under Arctic sea ice. Science 336:1408. doi:10.1126/Science.1215065

    Article  CAS  PubMed  Google Scholar 

  • Arrigo KR, Perovich DK, Pickart RS, Brown ZW, van Dijken GL, Lowry KE, Mills MM, Palmer MA, Balch WM, Bates NR, Benitez-Nelson CR, Brownlee E, Frey KE, Laney SR, Mathis J, Matsuoka A, Mitchell BG, Moore GW, Reyolds RA, Sosik HM, Swift JH (2014) Phytoplankton blooms beneath the sea ice in the Chukchi sea. Deep Sea Res II 105:1–16. doi:10.1016/j.dsr2.2014.03.018

    Article  Google Scholar 

  • Barnathan G (2009) Non-methylene-interrupted fatty acids from marine invertebrates: occurrence, characterization and biological properties. Biochimie 91:671–678. doi:10.1016/j.biochi.2009.03.020

    Article  CAS  PubMed  Google Scholar 

  • Boetius A et al (2013) Export of algal biomass from the melting Arctic sea ice. Science 339:1430–1432. doi:10.1126/science.1231346

    Article  CAS  PubMed  Google Scholar 

  • Brown ZW, Arrigo KR (2012) Contrasting trends in sea ice and primary production in the Bering Sea and Arctic Ocean. ICES J Mar Sci 69:1180–1193. doi:10.1093/icesjms/fss113

    Article  Google Scholar 

  • Budge SM, Parrish CC (1998) Lipid biogeochemistry of plankton, settling matter and sediments in Trinity Bay, Newfoundland. II. Fatty acids. Org Geochem 29:1547–1559. doi:10.1016/S0146-6380(98)00177-6

    Article  CAS  Google Scholar 

  • Budge SM, Iverson SJ, Koopman HN (2006) Studying trophic ecology in marine ecosystems using fatty acids: a primer on analysis and interpretation. Mar Mammal Sci 22:759–801. doi:10.1111/J.1748-7692.2006.00079.X

    Article  Google Scholar 

  • Budge SM, Springer AM, Iverson SJ, Sheffield G (2007) Fatty acid biomarkers reveal niche separation in an Arctic benthic food web. Mar Ecol Prog Ser 336:305–309. doi:10.3354/meps336305

    Article  CAS  Google Scholar 

  • Budge SM, Wooller MJ, Springer AM, Iverson SJ, McRoy CP, Divoky GJ (2008) Tracing carbon flow in an arctic marine food web using fatty acid-stable isotope analysis. Oecologia 157:117–129. doi:10.1007/S00442-008-1053-7

    Article  CAS  PubMed  Google Scholar 

  • Budge SM, Wang SW, Hollmen TE, Wooller MJ (2011) Carbon isotopic fractionation in eider adispose tissue vaies with fatty acid structure: implications for trophic studies. J Exp Biol 214:3790–3800. doi:10.1242/jeb.057596

    Article  CAS  PubMed  Google Scholar 

  • Burns JJ, Frost KJ (1979) The natural history and ecology of the bearded seal, Erignathus barbatus. Environ Assess Alaskan Cont Shelf Final Rep 19:311–392

    Google Scholar 

  • Cameron MF, Boveng PL (2009) Habitat use and seasonal movements of adult and sub-adult bearded seals. Alaska Fisheries Science Center Quarterly Report October–November–December

  • Cameron MF, Bengtson JL, Boveng PL, Jansen JK, Kelly BP, Dahle SP, Logerwell EA, Overland JE, Sabine CL, Waring GT, Wilder JM (2010) Status review of the bearded seal (Erignathus barbatus). United States Department of Commerce, NOAA Technical Memorandum. NMFS-AFSC-211

  • Cleator HJ, Stirling I, Smith TG (1989) Underwater vocalizations of the bearded seal (Erignathus barbatus). Can J Zool 67:1900–1910. doi:10.1139/z89-272

    Article  Google Scholar 

  • Collins G (1940) Habits of the Pacific walrus (Odobenus divergens). J Mammal 21:138–144

    Article  Google Scholar 

  • Cooper MH, Budge SM, Springer AM, Sheffield G (2009) Resource partitioning by sympatric pagophilic seals in Alaska: monitoring effects of climate variation with fatty acids. Polar Biol 32:1137–1145. doi:10.1007/s00300-009-0614-5

    Article  Google Scholar 

  • Costa DP (1991) Reproductive and foraging energetics of high latitude penguins, albatrosses and pinnipeds: implications for life history patterns. Am Zool 31:111–130

    Article  Google Scholar 

  • Crawford JA, Quakenbush LT, Citta JJ (2015) A comparison of ringed and bearded seal diet, condition and productivity between historical (1975–1984) and recent (2003–2012) periods in the Alaskan Bering and Chukchi seas. Prog Oceanogr 136:133–150. doi:10.1016/j.pocean.2015.05.011

    Article  Google Scholar 

  • Dalsgaard J, St John M, Kattner G, Muller-Navarra D, Hagen W (2003) Fatty acid trophic markers in the pelagic marine environment. Adv Mar Biol 46:225–340. doi:10.1016/S0065-2881(03)46005-7

    Article  PubMed  Google Scholar 

  • Dehn LA, Sheffield GG, Follmann EH, Duffy LK, Thomas DL, O’Hara TM (2007) Feeding ecology of phocid seals and some walrus in the Alaskan and Canadian Arctic as determined by stomach contents and stable isotope analysis. Polar Biol 30:167–181. doi:10.1007/s00300-006-0171-0

    Article  Google Scholar 

  • Dissen J (2015) Fatty acid profiles of Alaskan Arctic forage fishes: evidence of regional and spatial variation. Master thesis, Marine Science and Limnology, University of Alaska Fairbanks, Fairbanks, AK, USA

  • Divine LM, Bluhm BA, Mueter FJ, Iken K (2015) Diet analysis of Alaska Arctic snow crabs (Chionoecetes opilio) using stomach contents and δ13C and δ15N stable isotopes. Deep Sea Res II. doi:10.1016/j.dsr2.2015.11.009

    Google Scholar 

  • Donaldson GM, Chapdelaine G, Andrews JD (1995) Predation of thick-billed murres, Uria lomvia, at two breeding colonies by polar bears, Ursus maritimus, and walruses, Odobenus rosmarus. Can Field Nat 109:112–114

    Google Scholar 

  • Falk-Petersen S, Haug T, Nilssen KT, Wold A, Dahl TM (2004) Lipids and trophic linkages in harp seals (Phoca groenlandica) from the eastern Barents Sea. Polar Res 23:43–50. doi:10.1111/j.1751-8369.2004.tb00128.x

    Article  Google Scholar 

  • Fay FH (1982) Ecology and Biology of the Pacific Walrus, Odobenus rosmarus divergens Illiger. N Am Fauna 74:1–279

    Article  Google Scholar 

  • Fay FH, Bukhtiyarov YA, Stoker SW, Shults LM (1984) Foods of the Pacific walrus in winter and spring in the Bering Sea. In: Soviet-American cooperative. Research on marine mammals, Pinnipeds, vol 1. U.S. Department of Commerce, NOAA, NMFS

  • Folch J (1957) A simple method for the isolation and purification of total lipides from animal tissues. J Biol Chem 226:497–509

    CAS  PubMed  Google Scholar 

  • Gosselin M, Levasseur M, Wheeler PA, Horner RA, Booth BC (1997) New measurements of phytoplankton and ice algal production in the Arctic Ocean. Deep Sea Res II 44:1623–1644. doi:10.1016/S0967-0645(97)00054-4

    Article  CAS  Google Scholar 

  • Graham C, Oxtoby LE, Wang SW, Budge SM, Wooller MJ (2014) Sourcing fatty acids to juvenile polar cod (Boreogadus saida) in the Beaufort Sea using compound-specific stable carbon isotope analyses. Polar Biol 37:697–705. doi:10.1007/s00300-014-1470-5

    Article  Google Scholar 

  • Grebmeier JM (2012) Shifting patterns of life in the Pacific Arctic and sub-Arctic seas. Annu Rev Mar Sci 4:63–78. doi:10.1146/annurev-marine-120710-100926

    Article  Google Scholar 

  • Grebmeier JM, Cooper LW, Feder HM, Sirenko BI (2006a) Ecosystem dynamics of the Pacific-influenced northern Bering and Chukchi seas in the Amerasian Arctic. Prog Oceanogr 71:331–361. doi:10.1016/j.pocean.2006.10.001

    Article  Google Scholar 

  • Grebmeier JM, Overland JE, Moore SE, Farley EV, Carmack EC, Cooper LW, Frey KE, Helle JH, McLaughlin FA, McNutt SL (2006b) A major ecosystem shift in the northern Bering Sea. Science 311:1461–1464. doi:10.1126/science.1121365

    Article  CAS  PubMed  Google Scholar 

  • Harington CR (2008) The evolution of Arctic marine mammals. Ecol Appl 18:S23–S40. doi:10.1890/06-0624.1

    Article  CAS  PubMed  Google Scholar 

  • Hunt GL, Stabeno P, Walters G, Sinclair E, Brodeur RD, Napp JM, Bond NA (2002) Climate change and control of the southeastern Bering Sea pelagic ecosystem. Deep Sea Res II 49:5821–5853. doi:10.1016/s0967-0645(02)00321-1

    Article  Google Scholar 

  • Hunt GL, Stabeno PJ, Strom S, Napp JM (2008) Patterns of spatial and temporal variation in the marine ecosystem of the southeastern Bering Sea, with special reference to the Pribilof Domain. Deep Sea Res II 55:1919–1944. doi:10.1016/j.dsr2.2008.04.032

    Article  Google Scholar 

  • Hunt GL, Coyle KO, Eisner LB, Farley EV, Heintz RA, Mueter F, Nappy JM, Overland JE, Ressler PH, Salo S, Stabeno PJ (2011) Climate impacts on eastern Bering Sea foodwebs: a synthesis of new data and an assessment of the Oscillating Control Hypothesis. Ices J Mar Sci 68:1230–1243. doi:10.1093/icesjms/fsr036

    Article  Google Scholar 

  • Huntington HP, Quakenbush LT (2013) Traditional knowledge regarding walrus near Point Hope, Alaska Report. Native Village of Point Hope, Bureau of Ocean Energy Management

  • Huntington HP, Quakenbush LT, Nelson MN (2016) Effects of changing sea ice on marine mammals and subsistence hunters in northern Alaska from traditional knowledge interviews. Biol Lett 12:1–4. doi:10.1098/rsbl.2016.0198

    Article  Google Scholar 

  • Huntley ME, Lopez MDG (1992) Temperature-dependent production of marine copepods: a global synthesis. Am Nat 140:201–242

    Article  CAS  PubMed  Google Scholar 

  • Iverson SJ, Frost KJ, Lang SLC (2002) Fat content and fatty acid composition of forage fish and invertebrates in Prince William Sound, Alaska: factors contributing to among and within species variability. Mar Ecol Prog Ser 241:161–181. doi:10.3354/meps241161

    Article  CAS  Google Scholar 

  • Jay C, Fischbach A (2008) Pacific walrus response to Arctic sea ice losses. U.S. Department of the Interior United States Geological Survey, Anchorage, AK

  • Jay CV, Hills S (2005) Movements of walruses radio-tagged in Bristol Bay, Alaska. Arctic 58:192–202. doi:10.14430/arctic410

    Google Scholar 

  • Jay CV, Udevitz MS, Kwok R, Fischbach AS, Douglas DC (2010) Divergent movements of walrus and sea ice in the northern Bering Sea. Mar Ecol Prog Ser 407:293–302. doi:10.3354/meps08575

    Article  Google Scholar 

  • Jay CV, Fischbach AS, Kochnev AA (2012) Walrus areas of use in the Chukchi Sea during sparse sea ice cover. Mar Ecol Prog Ser 468:1–13. doi:10.3354/meps10057

    Article  Google Scholar 

  • Jay CV, Grebmeier JM, Fischbach AS, McDonald TL, Cooper LW, Hornsby F (2014) Pacific walrus (Odobenus rosmarus divergens) resource selection in the northern Bering Sea. PLoS One 9(4):e93035. doi:10.1371/journal.pone.0093035

    Article  PubMed  PubMed Central  Google Scholar 

  • Joseph JD (1982) Lipid composition of marine and estuarine invertebrates. Part II: Mollusca. Prog Lipid Res 21:109–153. doi:10.1016/0163-7827(82)90002-9

    Article  CAS  PubMed  Google Scholar 

  • Kawashima H (2005) Unusual minor nonmethylene-interrupted di-, tri-, and tetraenoic fatty acids in limpet gonads. Lipids 40:627–630. doi:10.1007/s11745-005-1424-y

    Article  CAS  PubMed  Google Scholar 

  • Kirsch PE, Iverson SJ, Bowen WD (2000) Effect of a low-fat diet on body composition and blubber fatty acids of captive juvenile harp seals (Phoca groenlandica). Physiol Biochem Zool 73:45–59

    Article  CAS  PubMed  Google Scholar 

  • Kolts JM, Lovvorn JR, North CA, Grebmeier JM, Cooper LW (2013a) Effects of body size, gender, and prey availability on diets of snow crabs in the northern Bering Sea. Mar Ecol Prog Ser 483:209–220. doi:10.3354/meps10292

    Article  Google Scholar 

  • Kolts JM, Lovvorn JR, North CA, Grebmeier JM, Cooper LW (2013b) Relative value of stomach contents, stable isotopes, and fatty acids as diet indicators for a dominant invertebrate predator (Chionoecetes opilio) in the northern Bering Sea. J Exp Mar Biol Ecol 449:274–283. doi:10.1016/j.jembe.2013.10.005

    Article  CAS  Google Scholar 

  • Kovacs KM, Lavigne DM (1992) Maternal investment in otariid seals and walruses. Can J Zoo 70:1953–1964. doi:10.1139/z92-265

    Article  Google Scholar 

  • Kryukova N, Kochnev A, Pereverzev A (2014) The influence of ice conditions on terrestrial haulouts of the pacific walrus Odobenus rosmarus divergens Illiger, 1815 in the Gulf of Anadyr, Bering Sea. Russ J Mar Biol 40:30–35

    Article  Google Scholar 

  • Lovvorn JR, Wilson JJ, McKay D, Bump JK, Cooper LW, Grebmeier JM (2010) Walruses attack spectacled eiders wintering in pack ice of the Bering Sea. Arctic 63:53–56. doi:10.14430/arctic646

    Article  Google Scholar 

  • Lowry LF, Fay F (1984) Seal eating by walruses in the Bering and Chukchi seas. Polar Biol 3:11–18

    Article  Google Scholar 

  • Lowry LF, Frost KJ, Burns JJ (1980) Feeding of bearded seals in the Bering and Chukchi seas and trophic interaction with Pacific walruses. Arctic 33:330–342. doi:10.14430/arctic2566

    Article  Google Scholar 

  • Lowry KE, van Dijken GL, Arrigo KR (2014) Evidence of under-ice phytoplankton blooms in the Chukchi Sea from 1998 to 2012. Deep Sea Res II 105:105–117. doi:10.1016/j.dsr2.2014.03.013

    Article  CAS  Google Scholar 

  • Mansfield A, Fisher H (1960) Age determination in the harbour seal, Phoca vitulina L. Nature 186:92

    Article  CAS  PubMed  Google Scholar 

  • McRoy CP, Goering JJ (1976) Annual budget of primary production in the Bering Sea. Mar Sci Comm 2:255–267

    Google Scholar 

  • Monroig O, Guinot D, Hontoria F, Tocher DR, Navarro JC (2012) Biosynthesis of essential fatty acids in Octopus vulgaris (Cuvier, 1797): molecular cloning, functional characterisation and tissue distribution of a fatty acyl elongase. Aquaculture 360:45–53. doi:10.1016/j.aquaculture.2012.07.016

    Article  Google Scholar 

  • Monson DH, Udevitz MS, Jay CV (2013) Estimating age ratios and size of Pacific Walrus herds on coastal haulouts using video imaging. Plos One 8:e69806. doi:10.1371/journal.pone.0069806

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  • Noongwook G, Huntington HP, George JC, Savoonga NV (2007) Traditional knowledge of the bowhead whale (Balaena mysticetus) around St. Lawrence Island. Alaska. Arctic 60:47–54. doi:10.14430/arctic264

    Google Scholar 

  • Nordstrom CA, Wilson LJ, Iverson SJ, Tollit DJ (2008) Evaluating quantitative fatty acid signature analysis (QFASA) using harbour seals Phoca vitulina richardsi in captive feeding studies. Mar Ecol Prog Ser 360:245–263. doi:10.3354/meps07378

    Article  Google Scholar 

  • Noren SR, Udevitz MS, Jay CV (2012) Bioenergetics model for estimating food requirements of female Pacific walruses Odobenus rosmarus divergens. Mar Ecol Prog Ser 460:261–275. doi:10.3354/meps09706

    Article  Google Scholar 

  • Noren SR, Udevitz MS, Jay CV (2014) Energy demands for maintenance, growth, pregnancy, lactation of female Pacific walruses (Odobenus rosmarus divergens). Physiol Biochem Zool 87:837–854. doi:10.1086/678237

    Article  PubMed  Google Scholar 

  • Oxtoby LE, Budge SM, Iken K, O’Brien DM, Wooller MJ (2016) Feeding ecologies of key bivalve and polychaete species as elucidated from fatty acid and compound-specific stable isotope analyses. Mar Ecol Prog Ser 557:161–175. doi:10.3354/meps11863

    Article  CAS  Google Scholar 

  • Paradis M, Ackman RG (1977) Potential for employing the distribution of anomalous non-methylene-interrupted dienoic fatty acids in several marine invertebrates as part of food web studies. Lipids 12:170–176. doi:10.1007/BF02533289

    Article  CAS  PubMed  Google Scholar 

  • Parnell AC, Inger R, Bearhop S, Jackson AL (2010) Source partitioning using stable isotopes: coping with too much variation. Plos One 5:e9672. doi:10.1371/journal.pone.0009672

    Article  PubMed  PubMed Central  Google Scholar 

  • Parrish CC (2013) Lipids in marine ecosystems. Int Sch Res Not Oceanogr 2013:1–16. doi:10.5402/2013/604045

    Google Scholar 

  • Perrette M, Yool A, Quartly GD, Popova EE (2011) Near-ubiquity of ice-edge blooms in the Arctic. Biogeosciences 8:515–524. doi:10.5194/bg-8-515-2011

    Article  Google Scholar 

  • Phillips DL, Koch PL (2002) Incorporating concentration dependence in stable isotope mixing models. Oecologia 130:114–125. doi:10.1007/s004420100786

    Article  PubMed  Google Scholar 

  • Quakenbush L, Citta J, Crawford J (2011) Biology of the bearded seal (Erignathus barbatus) in Alaska, 1961–2009. Final Report to National Marine Fisheries Service, Alaska Department of Fish and Game Arctic Marine Mammal Program

  • Quakenbush LT, Crawford JA, Citta JJ, Nelson MN (2016) Pinniped movements and foraging: village-based walrus habitat use studies in the Chukchi Sea. U.S. Dept. of the Interior, Bureau of Ocean Energy Management, Alaska Outer Continental Shelf Region, Anchorage, AK. OCS Study BOEM 2016-053

  • Ray GC, McCormick-Ray J, Berg P, Epstein HE (2006) Pacific walrus: benthic bioturbator of Beringia. J Exp Mar Biol Ecol 330:403–419. doi:10.1016/j.jembe.2005.12.043

    Article  Google Scholar 

  • Repenning CA (1976) Adaptive evolution of sea lions and walruses. Syst Biol 25:375–390. doi:10.2307/2412512

    Article  Google Scholar 

  • Rosen DAS, Winship AJ, Hoopes LA (2007) Thermal and digestive constraints to foraging behaviour in marine mammals. Phil Trans R Soc 362:2151–2168. doi:10.1098/rstb.2007.2108

    Article  Google Scholar 

  • Sakshaug E, Skjoldal HR (1989) Life at the ice edge. Ambio 18:60–67

    Google Scholar 

  • Seymour J, Horstmann-Dehn L, Wooller MJ (2014a) Inter-annual variability in the proportional contribution of higher trophic levels to the diet of Pacific walruses. Polar Biol 37:597–609. doi:10.1007/s00300-014-1460-7

    Article  Google Scholar 

  • Seymour J, Horstmann-Dehn L, Wooller MJ (2014b) Proportion of higher trophic-level prey in the diet of Pacific walruses (Odobenus rosmarus divergens). Polar Biol 37:941–952. doi:10.1007/s00300-014-1492-z

    Article  Google Scholar 

  • Sheffield G, Grebmeier JM (2009) Pacific walrus (Odobenus rosmarus divergens): differential prey digestion and diet. Mar Mammal Sci 25:761–777. doi:10.1111/j.1748-7692.2009.00316.x

    Article  Google Scholar 

  • Simpkins MA, Hiruki-Raring LM, Sheffield G, Grebmeier JM, Bengston JL (2003) Habitat selection by ice-associated pinnipeds near St. Lawrence Island, Alaska in March 2001. Polar Biol 26:577–586. doi:10.1007/s00300-003-0527-7

    Article  Google Scholar 

  • Stabeno PJ, Kachel NB, Moore SE, Napp JM, Sigler M, Yamaguchi A, Zerbini AN (2012) Comparison of warm and cold years on the southeastern Bering Sea shelf and some implications for the ecosystem. Deep Sea Res II 65–70:31–45. doi:10.1016/j.dsr2.2012.02.020

    Article  Google Scholar 

  • Sun MY, Zou L, Dai J, Ding H, Culp RA, Scranton MI (2004) Molecular carbon isotopic fractionation of algal lipids during decomposition in natural oxic and anoxic seawaters. Org Geochem 35:895–908. doi:10.1016/j.orggeochem.2004.04.001

    Article  CAS  Google Scholar 

  • Volkman JK, Johns RB, Gillan FT, Perry GJ, Bavor HJ (1980) Microbial lipids of an inter-tidal sediment 1. Fatty-acids and hydrocarbons. Geochim Cosmochim Acta 44:1133–1143. doi:10.1016/0016-7037(80)90067-8

    Article  CAS  Google Scholar 

  • Walsh JJ, McRoy CP (1986) Ecosystem analysis in the southeastern Bering Sea. Cont Shelf Res 5:259–288

    Article  Google Scholar 

  • Wang SW, Budge SM, Gradinger RR, Iken K, Wooller MJ (2014) Fatty acid and stable isotope characteristics of sea ice and pelagic particulate organic matter in the Bering Sea: tools for estimating sea ice algal contribution to Arctic food web production. Oecologia 174:699–712. doi:10.1007/s00442-013-2832-3

    Article  PubMed  Google Scholar 

  • Wang SW, Budge SM, Iken K, Gradinger RR, Springer AM, Wooller MJ (2015a) Importance of sympagic production to Bering Sea zooplankton as revealed from fatty acid-carbon stable isotope analyses. Mar Ecol Prog Ser 518:31–50. doi:10.3354/meps11076

    Article  Google Scholar 

  • Wang SW, Frost KJ, Whiting AV (2015b) Foraging ecology of ice seals in Kotzebue Sound, Alaska: insights from fatty acid markers. Mar Mammal Sci. doi:10.1111/mms.12284

    Google Scholar 

  • Wang SW, Springer AM, Budge SM, Horstmann-Dehn L, Quakenbush LT, Wooller MJ (2016) Carbon sources and trophic relationships of ice seals during recent environmental shifts in the Bering Sea. Ecol Appl. doi:10.1890/14-2421

    Google Scholar 

  • Wilt LM, Grebmeier JM, Miller TJ, Cooper LW (2014) Caloric content of Chukchi Sea benthic invertebrates: modeling spatial and environmental variation. Deep Sea Res II 102:97–106. doi:10.1016/j.dsr2.2013.09.025

    Article  CAS  Google Scholar 

  • Womble JN, Sigler MF, Willson MF (2009) Linking seasonal distribution patterns with prey availability in a central-place forager, the Steller sea lion. J Biogeogr 36:439–451. doi:10.1111/j.1365-2699.2007.01873.x

    Article  Google Scholar 

Download references

Acknowledgments

We are grateful to the Alaskan Native subsistence hunters who donated walrus tissues (Permit No. 50 CFR 18.23(a)(3)(b)(1)) for scientific research. Walrus samples were collected under the authority of permit number 50 CFR 18.23(a)(3)(b)(1) and held at University of Alaska Fairbanks (UAF) under a Letter of Authorization from USFWS to L. Horstmann. Bearded seal tissues were collected as part of a long-term biomonitoring program (National Marine Fisheries Service Scientific Research Permit No. 358-1787); tissues were analyzed and data sets were made available by Dr. S. Wang. Benthic prey samples from the Chukchi Sea were collected and analyzed by T. Schollmeier (UAF) as part of the Russian–American Long-term Census of the Arctic, the Chukchi Sea Offshore Monitoring In Drilling Area, and the Arctic Ecosystem Integrated Survey. POM and benthic prey samples from the Bering Sea were collected as part of the Bering Sea Ecosystem Study project. Data sets describing i-POM and p-POM samples were supplied by Dr. S Wang and those describing b-POM and benthic invertebrates were supplied by Dr. L. Oxtoby. Support for Dr. L. Oxtoby to conduct sample analyses at Dalhousie University was provided by a Water and Environmental Research Center (University of Alaska Fairbanks- UAF) travel grant. A. Timmins (Dalhousie University) and T. Howe (Alaska Stable Isotope Facility, UAF) assisted with sample extraction and instrumentation. Manuscript preparation was supported by a National Science Foundation GK-12 fellowship (Changing Alaska Science Education), a Dissertation Completion Fellowship (UAF), as well as by the Matthew Iya, Francis “Bud” Fay, Ken Turner, Kathryn E. and John Doyle, and Frances and Alfred Baker Memorial Funds.

Author information

Authors and Affiliations

  1. Institute of Marine Science, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 905 N. Koyukuk Drive, Fairbanks, AK, 99775, USA

    L. E. Oxtoby, L. Horstmann, S. W. Wang, T. Schollmeier & M. J. Wooller

  2. Alaska Stable Isotope Facility, Water and Environmental Research Center, University of Alaska Fairbanks, 306 Tanana Loop, Fairbanks, AK, 99775, USA

    L. E. Oxtoby, S. W. Wang & M. J. Wooller

  3. Department of Process Engineering and Applied Science, Dalhousie University, PO Box 1000, Halifax, NS, B3J 2X4, Canada

    S. M. Budge

  4. Institute of Arctic Biology, University of Alaska Fairbanks, 230 Arctic Health Research Building, Fairbanks, AK, 99775, USA

    D. M. O’Brien

Authors
  1. L. E. Oxtoby
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. L. Horstmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. S. M. Budge
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. D. M. O’Brien
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. S. W. Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. T. Schollmeier
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. M. J. Wooller
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

LEO wrote the manuscript. SMB, MJW, and LEO formulated the concept. SMB developed methodology for the fatty acid analysis. TS conducted the fieldwork for invertebrate sample collection. LEO and TS performed the fatty acid and compound-specific stable isotope analyses. LEO performed the data analysis based on helpful suggestions from LH, SMB, and DOB. LH, DOB, SWW, TS, and MJW provided substantive editorial advice.

Corresponding author

Correspondence to L. E. Oxtoby.

Ethics declarations

Funding

This study was funded by National Science Foundation (OPP grants #0902177 awarded to M. Wooller, K. Iken, L. Horstmann, and R. Gradinger and #0732767 awarded to K. Iken, B. Bluhm, and R. Gradinger) and by the North Pacific Research Board (Award #1227 awarded to K. Iken).

Conflict of interest

The authors declare that they have no conflicts of interest.

Ethical approval

All applicable institutional and/or national guidelines for the care and use of animals were followed.

Additional information

Communicated by Seth Newsome.

Electronic supplementary material

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Oxtoby, L.E., Horstmann, L., Budge, S.M. et al. Resource partitioning between Pacific walruses and bearded seals in the Alaska Arctic and sub-Arctic. Oecologia 184, 385–398 (2017). https://doi.org/10.1007/s00442-017-3883-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00442-017-3883-7

Keywords

Search

Navigation