Rapid anthropogenic environmental change is expected to impact a host of ecological parameters in Southern Ocean ecosystems. Of critical concern are the consequences of these changes on the range of species that show fidelity to migratory destinations, as philopatry is hypothesized to help or hinder adaptation to climate change depending on the circumstances. Many baleen whales show philopatry to feeding grounds and are also capital breeders that meet migratory and reproductive costs through seasonal energy intake. Southern right whales (Eubalaena australis, SRWs) are capital breeders that have a strong relationship between reproductive output and foraging success. The population dynamics of South Africa's population of SRWs are characterized by two distinct periods: the 1990s, a period of high calving rates; and the late 2010s, a period associated with lowered calving rates. Here we use analyses of stable carbon (δ13 C) and nitrogen (δ15 N) isotope values from SRW biopsy samples (n = 122) collected during these two distinct periods to investigate foraging ecology of the South African population of SRWs over a time period coincident with the demographic shift. We show that South African SRWs underwent a dramatic northward shift, and diversification, in foraging strategy from 1990s to 2010s. Bayesian mixing model results suggest that during the 1990s, South African SRWs foraged on prey isotopically similar to South Georgia/Islas Georgias del Sur krill. In contrast, in the 2010s, South African SRWs foraged on prey isotopically consistent with the waters of the Subtropical Convergence, Polar Front and Marion Island. We hypothesize that this shift represents a response to changes in preferred habitat or prey, for example, the decrease in abundance and southward range contraction of Antarctic krill. By linking reproductive decline to changing foraging strategies for the first time in SRWs, we show that altering foraging strategies may not be sufficient to adapt to a changing ocean.

Centre for Coastal Studies Provincetown MA USA

Consejo Nacional de Investigaciones Científicas y Técnicas Laboratorio de Ecología Evolutiva Humana (LEEH Facultad de Ciencias Sociales Unidad de Enseñanza Universitaria Quequén UNCPBA Buenos Aires Argentina

Department of Biology and Ecology Faculty of Science University of Ostrava Ostrava Czech Republic

Department of Zoology and Entomology Mammal Research Institute University of Pretoria Pretoria South Africa

Department of Zoology Faculty of Science Charles University Prague Czech Republic

Dyer Island Conservation Trust Great White House Kleinbaai South Africa

Instituto de Conservación de Ballenas Buenos Aires Argentina

Ivanhoe Sea Safaris Gansbaai South Africa

Marine Evolution and Conservation Group Groningen Institute of Evolutionary Life Sciences University of Groningen Groningen The Netherlands

School of Biological Sciences University of Auckland Auckland New Zealand

School of Biological Sciences University of Utah Salt Lake City UT USA

Stable Isotope Biogeochemistry Laboratory Department of Earth Sciences Durham University Durham UK

Zobrazit více v PubMed

Abrahms, B., Hazen, E. L., Aikens, E. O., Savoca, M. S., Goldbogen, J. A., Bograd, S. J., Jacox, M. G., Irvine, L. M., Palacios, D. M., & Mate, B. R. (2019). Memory and resource tracking drive blue whale migrations. Proceedings of the National Academy of Sciences of the United States of America, 116(12), 5582-5587. https://doi.org/10.1073/pnas.1819031116

Allen, J., Weinrich, M., Hoppitt, W., & Rendell, L. (2013). Network-based diffusion analysis reveals cultural transmission of lobtail feeding in humpback whales. Science, 340(6131), 485-488. https://doi.org/10.1126/science.1231976

Atkinson, A., Hill, S. L., Pakhomov, E. A., Siegel, V., Reiss, C. S., Loeb, V. J., Steinberg, D. K., Schmidt, K., Tarling, G. A., Gerrish, L., & Sailley, S. F. (2019). Krill (Euphausia superba) distribution contracts southward during rapid regional warming. Nature Climate Change, 9(2), 142-147. https://doi.org/10.1038/s41558-018-0370-z

Atkinson, A., Siegel, V., Pakhomov, E., & Rothery, P. (2004). Long-term decline in krill stock and increase in salps within the Southern Ocean. Nature, 432(7013), 100-103. https://doi.org/10.1038/nature02996

Bannister, J. (2001). Status of southern right whales (Eubalaena australis) off Australia. Journal of Cetacean Research & Management, 2, 103-110.

Barbosa, A., Benzal, J., de León, A., & Moreno, J. (2012). Population decline of chinstrap penguins (Pygoscelis antarctica) on Deception Island, South Shetlands, Antarctica. Polar Biology, 35(9), 1453-1457. https://doi.org/10.1007/s00300-012-1196-1

Best, P. B. (1990). Trends in the inshore right whale population off South Africa, 1969-1987. Marine Mammal Science, 6(2), 93-108. https://doi.org/10.1111/j.1748-7692.1990.tb00232.x

Best, P. B. (1994). Seasonality of reproduction and the length of gestation in southern right whales Eubalaena australis. Journal of Zoology, 232(2), 175-189. https://doi.org/10.1111/j.1469-7998.1994.tb01567.x

Best, P. B. (2007). Whales and dolphins of the southern African subregion. Cambridge University Press.

Best, P. B., Brandão, A., & Butterworth, D. S. (2001). Demographic parameters of southern right whales off South Africa. Journal of Cetacean Research and Management Special Issue, 2(2), 161-169.

Best, P. B., Schaeff, C. M., Reeb, D., & Palsbøl, P. J. (2003). Composition and possible function of social groupings of southern right whales in south African waters. Behaviour, 140(11/12), 1469-1494. https://www.jstor.org/stable/4536102

Best, P. B., & Schell, D. (1996). Stable isotopes in southern right whale (Eubalaena australis) baleen as indicators of seasonal movements, feeding and growth. Marine Biology, 124(4), 483-494. https://doi.org/10.1007/BF00351030

Bindoff, N. L., Cheung, W. W. L., Kairo, J., Arístegui, J., Guinder, V. A., Hallberg, R., Hilmi, N., Jiao, N., Karim, M., Levin, L., O’Donoghue, S., Purca Cuicapusa, S. R., Rinkevich, B., Suga, T., Tagliabue, A., & Williamson, P. (2019). Changing ocean, marine ecosystems, and dependent communities. IPCC special report on the ocean and cryosphere in a changing climate (pp. 447-588). United Nations.

Böning, C. W., Dispert, A., Visbeck, M., Rintoul, S. R., & Schwarzkopf, F. U. (2008). The response of the Antarctic circumpolar current to recent climate change. Nature Geoscience, 1(12), 864-869. https://doi.org/10.1038/ngeo362

Borrell, A., Abad-Oliva, N., Gómez-Campos, E., Giménez, J., & Aguilar, A. (2012). Discrimination of stable isotopes in fin whale tissues and application to diet assessment in cetaceans. Rapid Communications in Mass Spectrometry, 26(14), 1596-1602. https://doi.org/10.1002/rcm.6267

Bracegirdle, T. J., Connolley, W. M., & Turner, J. (2008). Antarctic climate change over the twenty first century. Journal of Geophysical Research Atmospheres, 113(3), 1-13. https://doi.org/10.1029/2007JD008933

Brandão, A., Best, P., & Butterworth, D. S. (2010). Estimates of demographic parameters for southern right whales. IWC Scientific Committee Report, SC/62/BRG3, 1-17.

Brandão, A., Vermeulen, E., Ross-gillespie, A., Findlay, K., & Butterworth, D. S. (2018). Updated application of a photo-identification based assessment model to southern right whales in South African waters, focussing on inferences to be drawn from a series of appreciably lower counts of calving females over 2015 to 2017. IWC Scientific Committee Report, SC/67B/SH2. https://doi.org/10.13140/RG.2.2.14456.88325

Budge, S. M., Springer, A. M., Iverson, S. J., Sheffield, G., & Rosa, C. (2008). Blubber fatty acid composition of bowhead whales, Balaena mysticetus: Implications for diet assessment and ecosystem monitoring. Journal of Experimental Marine Biology and Ecology, 359(1), 40-46. https://doi.org/10.1016/j.jembe.2008.02.014

Buelow, C. A., Reside, A. E., Baker, R., & Sheaves, M. (2018). Stable isotopes reveal opportunistic foraging in a spatiotemporally heterogeneous environment: Bird assemblages in mangrove forests. PLoS One, 13(11), https://doi.org/10.1371/journal.pone.0206145

Burrows, D. G., Reichert, W. L., & Bradley Hanson, M. (2014). Effects of decomposition and storage conditions on the δ13C and δ15N isotope values of killer whale (Orcinus orca) skin and blubber tissues. Marine Mammal Science, 30(2), 747-762. https://doi.org/10.1111/mms.12076

Busquets-Vass, G., Newsome, S. D., Calambokidis, J., Serra-Valente, G., Jacobsen, J. K., Aguíñiga-García, S., & Gendron, D. (2017). Estimating blue whale skin isotopic incorporation rates and baleen growth rates: Implications for assessing diet and movement patterns in mysticetes. PLoS One, 12(5), 1-25. https://doi.org/10.1371/journal.pone.0177880

Carroll, E. L., Baker, C. S., Watson, M., Alderman, R., Bannister, J., Gaggiotti, O. E., Gröcke, D. R., Patenaude, N., & Harcourt, R. (2015). Cultural traditions across a migratory network shape the genetic structure of southern right whales around Australia and New Zealand. Scientific Reports, 5(November), 1-12. https://doi.org/10.1038/srep16182

Carroll, E. L., Fewster, R. M., Childerhouse, S. J., Patenaude, N. J., Boren, L., & Baker, C. S. (2016). First direct evidence for natal wintering ground fidelity and estimate of juvenile survival in the New Zealand southern right whale Eubalaena australis. PLoS One, 11(1), 1-17. https://doi.org/10.1371/journal.pone.0146590

Carroll, E. L., Ott, P. H., McMillan, L. F., Galletti Vernazzani, B., Neveceralova, P., Vermeulen, E., Gaggiotti, O. E., Andriolo, A., Baker, C. S., Bamford, C., Best, P., Cabrera, E., Calderan, S., Chirife, A., Fewster, R. M., Flores, P. A. C., Frasier, T., Freitas, T. R. O., Groch, K., … Jackson, J. A. (2020). Genetic diversity and connectivity of southern right whales (Eubalaena australis) found in the Brazil and Chile-Peru wintering grounds and the south Georgia (Islas Georgias del Sur) feeding ground. Journal of Heredity, 111(3), 263-276. https://doi.org/10.1093/jhered/esaa010

Cartwright, R., Venema, A., Hernandez, V., Wyels, C., Cesere, J., & Cesere, D. (2019). Fluctuating reproductive rates in Hawaii’s humpback whales, Megaptera novaeangliae, reflect recent climate anomalies in the North Pacific. Royal Society Open Science, 6(3), 181463. https://doi.org/10.1098/rsos.181463

Cherel, Y., & Hobson, K. (2007). Geographical variation in carbon stable isotope signatures of marine predators: A tool to investigate their foraging areas in the Southern Ocean. Marine Ecology Progress Series, 329, 281-287. https://doi.org/10.3354/meps329281

Christiansen, F., Vivier, F., Charlton, C., Ward, R., Amerson, A., Burnell, S., & Bejder, L. (2018). Maternal body size and condition determine calf growth rates in southern right whales. Marine Ecology Progress Series, 592, 267-281. https://doi.org/10.3354/meps12522

Constable, A. J., Melbourne-Thomas, J., Corney, S. P., Arrigo, K. R., Barbraud, C., Barnes, D. K. A., Bindoff, N. L., Boyd, P. W., Brandt, A., Costa, D. P., Davidson, A. T., Ducklow, H. W., Emmerson, L., Fukuchi, M., Gutt, J., Hindell, M. A., Hofmann, E. E., Hosie, G. W., Iida, T., … Ziegler, P. (2014). Climate change and Southern Ocean ecosystems I: How changes in physical habitats directly affect marine biota. Global Change Biology, 20(10), 3004-3025. https://doi.org/10.1111/gcb.12623

Crespo, E. A., Pedraza, S. N., Dans, S. L., Svendsen, G. M., Degrati, M., & Coscarella, M. A. (2019). The southwestern Atlantic southern right whale, Eubalaena australis, population is growing but at a decelerated rate. Marine Mammal Science, 35(1), 93-107. https://doi.org/10.1111/mms.12526

Das, K., Holleville, O., Ryan, C., Berrow, S., Gilles, A., Ody, D., & Michel, L. N. (2017). Isotopic niches of fin whales from the Mediterranean Sea and the Celtic Sea (North Atlantic). Marine Environmental Research, 127, 75-83. https://doi.org/10.1016/j.marenvres.2017.03.009

Davis, G. E., Baumgartner, M. F., Bonnell, J. M., Bell, J., Berchok, C., Bort Thornton, J., Brault, S., Buchanan, G., Charif, R. A., Cholewiak, D., Clark, C. W., Corkeron, P., Delarue, J., Dudzinski, K., Hatch, L., Hildebrand, J., Hodge, L., Klinck, H., Kraus, S., … Van Parijs, S. M. (2017). Long-term passive acoustic recordings track the changing distribution of North Atlantic right whales (Eubalaena glacialis) from 2004 to 2014. Scientific Reports, 7(1), 1-12. https://doi.org/10.1038/s41598-017-13359-3

Davis, G. E., Baumgartner, M. F., Corkeron, P. J., Bell, J., Berchok, C., Bonnell, J. M., Bort Thornton, J., Brault, S., Buchanan, G. A., Cholewiak, D. M., Clark, C. W., Delarue, J., Hatch, L. T., Klinck, H., Kraus, S. D., Martin, B., Mellinger, D. K., Moors-Murphy, H., Nieukirk, S., … Van Parijs, S. M. (2020). Exploring movement patterns and changing distributions of baleen whales in the western North Atlantic using a decade of passive acoustic data. Global Change Biology, 26(9), 4812-4840. https://doi.org/10.1111/gcb.15191

de la Vega, C., Jeffreys, R. M., Tuerena, R., Ganeshram, R., & Mahaffey, C. (2019). Temporal and spatial trends in marine carbon isotopes in the Arctic Ocean and implications for food web studies. Global Change Biology, 25(12), 4116-4130. https://doi.org/10.1111/gcb.14832

Dehnhard, N., Achurch, H., Clarke, J., Michel, L. N., Southwell, C., Sumner, M. D., Eens, M., & Emmerson, L. (2020). High inter- and intraspecific niche overlap among three sympatrically breeding, closely related seabird species: Generalist foraging as an adaptation to a highly variable environment? Journal of Animal Ecology, 89(1), 104-119. https://doi.org/10.1111/1365-2656.13078

Del Castillo, C. E., Signorini, S. R., Karaköylü, E. M., & Rivero-Calle, S. (2019). Is the southern ocean getting greener? Geophysical Research Letters, 46(11), 6034-6040. https://doi.org/10.1029/2019GL083163

Dunn, O. J. (1964). Multiple comparisons using rank sums. Technometrics, 6(3), 241-252. https://doi.org/10.1080/00401706.1964.10490181

Espinasse, B., Pakhomov, E. A., Hunt, B. P. V., & Bury, S. J. (2019). Latitudinal gradient consistency in carbon and nitrogen stable isotopes of particulate organic matter in the Southern Ocean. Marine Ecology Progress Series, 631, 19-30. https://doi.org/10.3354/meps13137

Fleming, A. H., Clark, C. T., Calambokidis, J., & Barlow, J. (2016). Humpback whale diets respond to variance in ocean climate and ecosystem conditions in the California Current. Global Change Biology, 22(3), 1214-1224. https://doi.org/10.1111/gcb.13171

Forcada, J., & Trathan, P. N. (2009). Penguin responses to climate change in the Southern Ocean. Global Change Biology, 15(7), 1618-1630. https://doi.org/10.1111/j.1365-2486.2009.01909.x

Forcada, J., Trathan, P. N., Reid, K., & Murphy, E. J. (2005). The effects of global climate variability in pup production of Antarctic fur seals. Ecology, 86(9), 2408-2417. https://doi.org/10.1890/04-1153

Fraser, W., & Hofmann, E. (2003). A predator’s perspective on causal links between climate change, physical forcing and ecosystem response. Marine Ecology Progress Series, 265, 1-15. https://doi.org/10.3354/meps265001

Gelman, A., & Rubin, D. B. (1992). Inference from iterative simulation using multiple sequences. Statistical Science, 7(4), 457-472. https://doi.org/10.1214/ss/1177011136

Graham, B. S., Koch, P. L., Newsome, S. D., McMahon, K. W., & Aurioles, D. (2010). Using isoscapes to trace the movements and foraging behavior of top predators in oceanic ecosystems. In J. B. West, G. J. Bowen, T. E. Dawson, & K. P. Tu (Eds.), Isoscapes (pp. 299-318). Springer. https://doi.org/10.1007/978-90-481-3354-3_14

Greene, C. H., Pershing, A. J., Kenney, R. D., & Jossi, J. W. (2003). Impact of climate variability on the recovery of endangered north Atlantic right whales. Oceanography, 16(4), 98-103. https://doi.org/10.5670/oceanog.2003.16

Hanson, N. N., Wurster, C. M., Bird, M. I., Reid, K., & Boyd, I. L. (2009). Intrinsic and extrinsic forcing in life histories: Patterns of growth and stable isotopes in male Antarctic fur seal teeth. Marine Ecology Progress Series, 388, 263-272. https://doi.org/10.3354/meps08158

Haug, T., Falk-Petersen, S., Greenacre, M., Hop, H., Lindstrøm, U., Meier, S., Nilssen, K. T., & Wold, A. (2017). Trophic level and fatty acids in harp seals compared with common minke whales in the Barents Sea. Marine Biology Research, 13(9), 919-932. https://doi.org/10.1080/17451000.2017.1313988

Herman, D. P., Burrows, D. G., Wade, P. R., Durban, J. W., Matkin, C. O., Leduc, R. G., Barrett-Lennard, L. G., & Krahn, M. M. (2005). Feeding ecology of eastern North Pacific killer whales Orcinus orca from fatty acid, stable isotope, and organochlorine analyses of blubber biopsies. Marine Ecology Progress Series, 302, 275-291. https://doi.org/10.3354/meps302275

Hlista, B. L., Sosik, H. M., Traykovski, L. V. M., Kenney, R. D., & Moore, M. J. (2009). Seasonal and interannual correlations between right-whale distribution and calving success and chlorophyll concentrations in the Gulf of Maine, USA. Marine Ecology Progress Series, 394, 289-302. https://doi.org/10.3354/meps08267

Hobson, K. A. (1999). Tracing origins and migration of wildlife using stable isotopes: A review. Oecologia, 120(3), 314-326. https://doi.org/10.1007/s004420050865

Hobson, K. A., Barnett-Johnson, R., & Cerling, T. (2010). Using isoscapes to track animal migration. In Isoscapes (Issue November, pp. 273-298). Springer. https://doi.org/10.1007/978-90-481-3354-3_13

Hobson, K. A., Gibbs, H. L., & Gloutney, M. L. (1997). Preservation of blood and tissue samples for stable-carbon and stable-nitrogen isotope analysis. Canadian Journal of Zoology, 75(10), 1720-1723. https://doi.org/10.1139/z97-799

Hooker, S. K., Iverson, S. J., Ostrom, P., & Smith, S. C. (2001). Diet of northern bottlenose whales inferred from fatty-acid and stable-isotope analyses of biopsy samples. Canadian Journal of Zoology, 79(8), 1442-1454. https://doi.org/10.1139/cjz-79-8-1442

Horton, T. W., Zerbini, A. N., Andriolo, A., Danilewicz, D., & Sucunza, F. (2020). Multi-decadal humpback whale migratory route fidelity despite oceanographic and geomagnetic change. Frontiers in Marine Science, 7(June), 1-19. https://doi.org/10.3389/fmars.2020.00414

International Whaling Commission. (2013). Report of the IWC workshop on the assessment of southern right whales. Journal of Cetacean Research & Management, 14(Supplement), 442-451.

Iverson, S. J. (2009). Tracing aquatic food webs using fatty acids: From qualitative indicators to quantitative determination. In Lipids in aquatic ecosystems (pp. 281-308). Springer. https://doi.org/10.1007/978-0-387-89366-2

Jackson, A. L., Inger, R., Parnell, A. C., & Bearhop, S. (2011). Comparing isotopic niche widths among and within communities: SIBER - Stable Isotope Bayesian Ellipses in R. Journal of Animal Ecology, 80, 595-602. https://doi.org/10.1111/j.1365-2656.2011.01806.x

Jackson, J. A., Patenaude, N. J., Carroll, E. L., & Baker, C. S. (2008). How few whales were there after whaling? Inference from contemporary mtDNA diversity. Molecular Ecology, 17, 236-251. https://doi.org/10.1111/j.1365-294X.2007.03497.x

Jansen, E., Christensen, J. H., Dokken, T., Nisancioglu, K. H., Vinther, B. M., Capron, E., Guo, C., Jensen, M. F., Langen, P. L., Pedersen, R. A., Yang, S., Bentsen, M., Kjaer, H. A., Sadatzki, H., Sessford, E., & Stendel, M. (2020). Past perspectives on the present era of abrupt Arctic climate change. Nature Climate Change, 10(8), 714-721. https://doi.org/10.1038/s41558-020-0860-7

Jönsson, K. I., & Jonsson, K. I. (1997). Capital and income breeding as alternative tactics of resource use in reproduction. Oikos, 78(1), 57. https://doi.org/10.2307/3545800

Keith, S. A., & Bull, J. W. (2017). Animal culture impacts species’ capacity to realise climate-driven range shifts. Ecography, 40(2), 296-304. https://doi.org/10.1111/ecog.02481

Kokko, H., & Sutherland, W. J. (2001). Ecological traps in changing environments: Ecological and evolutionary consequences of a behaviourally mediated Allee effect. Evolutionary Ecology Research, 3, 537-551.

Lambertsen, R. H. (1987). A biopsy system for large whales and its use for cytogenetics. Journal of Mammalogy, 68(2), 443-445. https://doi.org/10.2307/1381495

Larsen, T., Ventura, M., Andersen, N., O’Brien, D. M., Piatkowski, U., & McCarthy, M. D. (2013). Tracing carbon sources through aquatic and terrestrial food webs using amino acid stable isotope fingerprinting. PLoS One, 8(9). https://doi.org/10.1371/journal.pone.0073441

Leaper, R., Cooke, J., Trathan, P., Reid, K., Rowntree, V., & Payne, R. (2006). Global climate drives southern right whale (Eubalaena australis) population dynamics. Biology Letters, 2(2), 289-292. https://doi.org/10.1098/rsbl.2005.0431

Lockyer, C. (1986). Body fat condition in northeast Atlantic fin whales, Balaenoptera physalus, and its relationship with reproduction and food resource. Canadian Journal of Fisheries and Aquatic Sciences, 43(1), 142-147. https://doi.org/10.1139/f86-015

Lockyer, C. (2007). All creatures great and smaller: A study in cetacean life history energetics. Journal of the Marine Biological Association of the United Kingdom, 87(4), 1035-1045. https://doi.org/10.1017/S0025315407054720

Logan, J. M., Pethybridge, H., Lorrain, A., Somes, C. J., Allain, V., Bodin, N., Choy, C. A., Duffy, L., Goñi, N., Graham, B., Langlais, C., Ménard, F., Olson, R., & Young, J. (2020). Global patterns and inferences of tuna movements and trophodynamics from stable isotope analysis. Deep-Sea Research Part II: Topical Studies in Oceanography, 175(May, 2019). https://doi.org/10.1016/j.dsr2.2020.104775

Lorrain, A., Pethybridge, H., Cassar, N., Receveur, A., Allain, V., Bodin, N., Bopp, L., Choy, C. A., Duffy, L., Fry, B., Goñi, N., Graham, B. S., Hobday, A. J., Logan, J. M., Ménard, F., Menkes, C. E., Olson, R. J., Pagendam, D. E., Point, D., … Young, J. W. (2020). Trends in tuna carbon isotopes suggest global changes in pelagic phytoplankton communities. Global Change Biology, 26(2), 458-470. https://doi.org/10.1111/gcb.14858

Lübcker, N., Reisinger, R., Oosthuizen, W., de Bruyn, P., van Tonder, A., Pistorius, P., & Bester, M. (2017). Low trophic level diet of juvenile southern elephant seals Mirounga leonina from Marion Island: A stable isotope investigation using vibrissal regrowths. Marine Ecology Progress Series, 577(June), 237-250. https://doi.org/10.3354/meps12240

Magozzi, S., Yool, A., Vander Zanden, H. B., Wunder, M. B., & Trueman, C. N. (2017). Using ocean models to predict spatial and temporal variation in marine carbon isotopes. Ecosphere, 8(5). https://doi.org/10.1002/ecs2.1763

Marón, C., Budge, S., Ward, R., Valenzuela, L., Di Martino, M., Ricciardi, M., Sironi, M., Uhart, M., Seger, J., & Rowntree, V. (2020). Fatty acids and stable isotopes (δ13C, δ15N) in southern right whale Eubalaena australis calves in relation to age and mortality at Península Valdés, Argentina. Marine Ecology Progress Series, 646, 189-200. https://doi.org/10.3354/meps13387

Mate, B. R., Best, P. B., Lagerquist, B. A., & Winsor, M. H. (2011). Coastal, offshore, and migratory movements of South African right whales revealed by satellite telemetry. Marine Mammal Science, 27(3), 455-476. https://doi.org/10.1111/j.1748-7692.2010.00412.x

McMahon, K. W., Hamady, L. L., & Thorrold, S. R. (2013a). A review of ecogeochemistry approaches to estimating movements of marine animals. Limnology and Oceanography, 58(2), 697-714. https://doi.org/10.4319/lo.2013.58.2.0697

McMahon, K. W., Hamady, L. L., & Thorrold, S. R. (2013b). Ocean ecogeochemistry: A review. Oceanography and Marine Biology: An Annual Review, 51. https://doi.org/10.1201/b15406

Mendes, R. F., Ramos, J. A., Paiva, V. H., Calado, J. G., Matos, D. M., & Ceia, F. R. (2018). Foraging strategies of a generalist seabird species, the yellow-legged gull, from GPS tracking and stable isotope analyses. Marine Biology, 165(10). https://doi.org/10.1007/s00227-018-3421-0

Mestre, J., Authier, M., Cherel, Y., Harcourt, R., McMahon, C. R., Hindell, M. A., Charrassin, J.-B., & Guinet, C. (2020). Decadal changes in blood δ13C values, at-sea distribution, and weaning mass of southern elephant seals from Kerguelen Islands. Proceedings of the Royal Society B: Biological Sciences, 287(1933), 20201544. https://doi.org/10.1098/rspb.2020.1544

Moore, J., & Semmens, B. X. (2008). Incorporating uncertainty and prior information into stable isotope mixing models. Ecology Letters, 11(5), 470-480. https://doi.org/10.1111/j.1461-0248.2008.01163.x

Moore, S. E., Wynne, K. M., Kinney, J. C., & Grebmeier, J. M. (2007). Gray whale occurrence and forage southeast of Kodiak, Island. Alaska. Marine Mammal Science, 23(2), 419-428. https://doi.org/10.1111/j.1748-7692.2007.00102.x

Murphy, E. J., Trathan, P. N., Watkins, J. L., Reid, K., Meredith, M. P., Forcada, J., Thorpe, S. E., Johnston, N. M., & Rothery, P. (2007). Climatically driven fluctuations in Southern Ocean ecosystems. Proceedings of the Royal Society B: Biological Sciences, 274(1629), 3057-3067. https://doi.org/10.1098/rspb.2007.1180

Nelson, M. A., Quakenbush, L. T., Mahoney, B. A., Taras, B. D., & Wooller, M. J. (2018). Fifty years of Cook Inlet beluga whale feeding ecology from isotopes in bone and teeth. Endangered Species Research, 36, 77-87. https://doi.org/10.3354/esr00890

Newsome, S. D., Chivers, S. J., & Berman Kowalewski, M. (2018). The influence of lipid-extraction and long-term DMSO preservation on carbon (δ13C) and nitrogen (δ15N) isotope values in cetacean skin. Marine Mammal Science, 34(2), 277-293. https://doi.org/10.1111/mms.12454

Newsome, S. D., Clementz, M. T., & Koch, P. L. (2010). Using stable isotope biogeochemistry to study marine mammal ecology. Marine Mammal Science, 26(3), 509-572. https://doi.org/10.1111/j.1748-7692.2009.00354.x

Newsome, S. D., Etnier, M., Kurle, C., Waldbauer, J., Chamberlain, C., & Koch, P. (2007). Historic decline in primary productivity in western Gulf of Alaska and eastern Bering Sea: isotopic analysis of northern fur seal teeth. Marine Ecology Progress Series, 332, 211-224. https://doi.org/10.3354/meps332211

Newsome, S. D., Martinez del Rio, C., Bearhop, S., & Phillips, D. L. (2007). A niche for stable isotope ecology. Frontiers in Ecology and the Environment, 5(8), 429-436. https://doi.org/10.1890/060150.01

Olsen, E., & Grahl-Nielsen, O. (2003). Blubber fatty acids of minke whales: Stratification, population identification and relation to diet. Marine Biology, 142(1), 13-24. https://doi.org/10.1007/s00227-002-0934-2

Orr, J. C., Fabry, V. J., Aumont, O., Bopp, L., Doney, S. C., Feely, R. A., Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F., Key, R. M., Lindsay, K., Maier-Reimer, E., Matear, R., Monfray, P., Mouchet, A., Najjar, R. G., Plattner, G.-K., Rodgers, K. B., … Yool, A. (2005). Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms. Nature. https://doi.org/10.1038/nature04095

Orsi, A. H., & Harris, U. (2019). Fronts of the Antarctic circumpolar current - GIS data, ver. 1. Australian Antarctic Data Centre. https://data.aad.gov.au/metadata/records/antarctic_circumpolar_current_fronts

Parnell, A. C., Inger, R., Bearhop, S., & Jackson, A. L. (2010). Source partitioning using stable isotopes: Coping with too much variation. PLoS One, 5(3), e9672. https://doi.org/10.1371/journal.pone.0009672

Patenaude, N. J., & Baker, C. S. (2001). Population status and habitat use of southern right whales in the sub-Antarctic Auckland Islands of New Zealand. Journal of Cetacean Research & Management Special Issue, 2(July, 1993), 111-116.

Payne, R. (1986). Long term behavioral studies of the southern right whale (Eubalaena australis). Reports - International Whaling Commission, Special Issue, 10, 161-167.

Payne, R., Brazier, O., Dorsey, E. M., Perkins, J. S., Rowntree, V. J., & Titus, A. (1983). External features in southern right whales, Eubalaena australis, and their use in identifying individuals. In R Payne (Ed.), Communication and behavior of whales (1st ed., pp. 295-328). Westview Press.

Peterson, B. J., & Fry, B. (1987). Stable isotopes in ecosystem studies. Annual Review of Ecology and Systematics, 18, 293-320. https://doi.org/10.1146/annurev.es.18.110187.001453

Phillips, D. L., Inger, R., Bearhop, S., Jackson, A. L., Moore, J. W., Parnell, A. C., Semmens, B. X., & Ward, E. J. (2014). Best practices for use of stable isotope mixing models in food-web studies. Canadian Journal of Zoology, 92(10), 823-835. https://doi.org/10.1139/cjz-2014-0127

Plummer, M. (2018). rjags: Bayesian graphical models using MCMC. R Package Version, 4-8. https://CRAN.R-Project.Org/Package=rjags

Pomerleau, C., Heide-Jørgensen, M. P., Ferguson, S. H., Stern, H. L., Høyer, J. L., & Stern, G. A. (2017). Reconstructing variability in West Greenland ocean biogeochemistry and bowhead whale (Balaena mysticetus) food web structure using amino acid isotope ratios. Polar Biology, 40(11), 2225-2238. https://doi.org/10.1007/s00300-017-2136-x

Quillfeldt, P., Masello, J. F., McGill, R. A. R., Adams, M., & Furness, R. W. (2010). Moving polewards in winter: A recent change in the migratory strategy of a pelagic seabird? Frontiers in Zoology, 7, 1-11. https://doi.org/10.1186/1742-9994-7-15

R Core Team. (2020). R: A language and environment for statistical computing. R Foundation for Statistical Computing. https://www.r-project.org/

Reeves, R., Rolland, R., & Clapham, P. (2001). Causes of reproductive failure in North Atlantic right whales: New avenues of research. Northeast Fisheries Science Center Report of a Workshop Held 26-28 April 2000, Falmouth, Massachusetts, 2-17. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.318.8720&rep=rep1&type=pdf

Reid, K., & Croxall, J. P. (2001). Environmental response of upper trophic-level predators reveals a system change in an Antarctic marine ecosystem. Proceedings of the Royal Society B: Biological Sciences, 268(1465), 377-384. https://doi.org/10.1098/rspb.2000.1371

Rendell, L., & Whitehead, H. (2001). Culture in whales and dolphins. Behavioral and Brain Sciences, 24(2), 309-382. https://doi.org/10.1017/S0140525X0100396X

Rogers, A. D., Frinault, B. A. V., Barnes, D. K. A., Bindoff, N. L., Downie, R., Ducklow, H. W., Friedlaender, A. S., Hart, T., Hill, S. L., Hofmann, E. E., Linse, K., McMahon, C. R., Murphy, E. J., Pakhomov, E. A., Reygondeau, G., Staniland, I. J., Wolf-Gladrow, D. A., & Wright, R. M. (2020). Antarctic futures: An assessment of climate-driven changes in ecosystem structure, function, and service provisioning in the southern ocean. Annual Review of Marine Science, 12, 87-120. https://doi.org/10.1146/annurev-marine-010419-011028

Rowntree, V. J., Uhart, M. M., Sironi, M., Chirife, A., Di Martino, M., La Sala, L., Musmeci, L., Mohamed, N., Andrejuk, J., McAloose, D., Sala, J. E., Carribero, A., Rally, H., Franco, M., Adler, F. R., Brownell, R. L., Seger, J., & Rowles, T. (2013). Unexplained recurring high mortality of southern right whale Eubalaena australis calves at Península Valdés, Argentina. Marine Ecology Progress Series, 493, 275-289. https://doi.org/10.3354/meps10506

Ruiz-Cooley, R. I., Gendron, D., Aguíñiga, S., Mesnick, S., & Carriquiry, J. D. (2004). Trophic relationships between sperm whales and jumbo squid using stable isotopes of C and N. Marine Ecology Progress Series, 277, 275-283. https://doi.org/10.3354/meps277275

Ryan, C., McHugh, B., Trueman, C. N., Sabin, R., Deaville, R., Harrod, C., Berrow, S. D., & O’Connor, I. (2013). Stable isotope analysis of baleen reveals resource partitioning among sympatric rorquals and population structure in fin whales. Marine Ecology Progress Series, 479, 251-261. https://doi.org/10.3354/meps10231

Schlaepfer, M. A., Runge, M. C., & Sherman, P. W. (2002). Ecological and evolutionary traps. Trends in Ecology & Evolution, 17(10), 474-480. https://doi.org/10.1016/S0169-5347(02)02580-6

Seyboth, E., Groch, K. R., Dalla Rosa, L., Reid, K., Flores, P. A. C., & Secchi, E. R. (2016). Southern right whale (Eubalaena australis) reproductive success is influenced by krill (Euphausia superba) density and climate. Scientific Reports, 6. https://doi.org/10.1038/srep28205

Silva, M. A., Borrell, A., Prieto, R., Gauffier, P., Bérubé, M., Palsbøl, P. J., & Colaço, A. (2019). Stable isotopes reveal winter feeding in different habitats in blue, fin and sei whales migrating through the Azores. Royal Society Open Science, 6(8). https://doi.org/10.1098/rsos.181800

Smith, D. T., & Jacka, J. (2003). Extents of Antarctic sea ice - GIS data - 1973-1999, Ver. 1. Australian Antarctic Data Centre. https://data.aad.gov.au/metadata/records/sea_ice_extent_gis

Smith, T. D., Reeves, R. R., Josephson, E. A., & Lund, J. N. (2012). Spatial and seasonal distribution of American whaling and whales in the age of sail. PLoS One, 7(4). https://doi.org/10.1371/journal.pone.0034905

Sokolov, S., & Rintoul, S. R. (2009). Circumpolar structure and distribution of the antarctic circumpolar current fronts: 2. Variability and relationship to sea surface height. Journal of Geophysical Research: Oceans, 114(11), 1-15. https://doi.org/10.1029/2008JC005248

Sonnerup, R. E., Quay, P. D., McNichol, A. P., Bullister, J. L., Westby, T. A., & Anderson, H. L. (1999). Reconstructing the oceanic 13C Suess Effect. Global Biogeochemical Cycles, 13(4), 857-872. https://doi.org/10.1029/1999GB900027

Stock, B. C., Jackson, A. L., Ward, E. J., Parnell, A. C., Phillips, D. L., & Semmens, B. X. (2018). Analyzing mixing systems using a new generation of Bayesian tracer mixing models. PeerJ, 2018(6), 1-27. https://doi.org/10.7717/peerj.5096

Stock, B. C., & Semmens, B. X. (2016a). MixSIAR GUI user manual. Version 3.1, March, 1-42. https://doi.org/10.5281/zenodo.47719

Stock, B. C., & Semmens, B. X. (2016b). Unifying error structures in commonly used biotracer mixing models. Ecology, 97(10), 2562-2569. https://doi.org/10.1002/ecy.1517

Suess, H. E. (1955). Radiocarbon concentration in modern wood. Science, 122(3166), 415-417. https://doi.org/10.1126/science.122.3166.415-a

Todd, S. K. (1997). Dietary patterns of humpback whales (Megaptera novaeangliae) in the Northwest Atlantic: Evidence from 13C and 15N stable isotopes. Doctoral (PhD) Thesis, Memorial University of Newfoundland.

Todd, S., Ostrom, P., Lien, J., & Abrajano, J. (1997). Use of biopsy samples of humpback whale (Megaptera novaeangliae) skin for stable isotope (δ13C) determination. Journal of Northwest Atlantic Fishery Science, 22(July), 71-76. https://doi.org/10.2960/J.v22.a6

Tormosov, D. D., Mikhaliev, Y. A., Best, P. B., Zemsky, V. A., Sekiguchi, K., & Brownell, R. L. (1998). Soviet catches of southern right whales Eubalaena australis, 1951-1971. Biological data and conservation implications. Biological Conservation, 86(2), 185-197. https://doi.org/10.1016/S0006-3207(98)00008-1

Townsend, C. H. (1935). The distribution of certain whales as shown by logbook records of American whaleships. Zoologica, 19, 3-50.

Trathan, P. N., Forcada, J., & Murphy, E. J. (2007). Environmental forcing and Southern Ocean marine predator populations: Effects of climate change and variability. Philosophical Transactions of the Royal Society B: Biological Sciences, 362(1488), 2351-2365. https://doi.org/10.1098/rstb.2006.1953

Tulloch, V. J. D., Plagányi, É. E., Brown, C., Richardson, A. J., & Matear, R. (2019). Future recovery of baleen whales is imperiled by climate change. Global Change Biology, 25(4), 1263-1281. https://doi.org/10.1111/gcb.14573

Valenzuela, L. O., Rowntree, V., Sironi, M., & Seger, J. (2018). Stable isotopes (δ15N, δ13C, δ34S) in skin reveal diverse food sources used by southern right whales Eubalaena australis. Marine Ecology Progress Series, 603, 243-255. https://doi.org/10.3354/meps12722

Valenzuela, L. O., Sironi, M., Rowntree, V. J., & Seger, J. (2009). Isotopic and genetic evidence for culturally inherited site fidelity to feeding grounds in southern right whales (Eubalaena australis). Molecular Ecology, 18(5), 782-791. https://doi.org/10.1111/j.1365-294X.2008.04069.x

Vehtari, A., Gelman, A., & Gabry, J. (2017). Practical Bayesian model evaluation using leave-one-out cross-validation and WAIC. Statistics and Computing, 27(5), 1413-1432. https://doi.org/10.1007/s11222-016-9696-4

Vermeulen, E., Wilkinson, C., Thornton, M., Peters, I. T., & Findlay, K. (2018). Report on the mammal research institute whale unit southern right whale survey - 2017. IWC Scientific Committee Report, SC/67B/SH/. https://doi.org/10.13140/RG.2.2.33382.45125

Ward, E. J., Holmes, E. E., & Balcomb, K. C. (2009). Quantifying the effects of prey abundance on killer whale reproduction. Journal of Applied Ecology, 46(3), 632-640. https://doi.org/10.1111/j.1365-2664.2009.01647.x

Whitehead, H., Rendell, L., Osborne, R. W., & Würsig, B. (2004). Culture and conservation of non-humans with reference to whales and dolphins: Review and new directions. Biological Conservation, 120(3), 427-437. https://doi.org/10.1016/j.biocon.2004.03.017

Williams, R., Vikingsson, G. A., Gislason, A., Lockyer, C., New, L., Thomas, L., & Hammond, P. S. (2013). Evidence for density-dependent changes in body condition and pregnancy rate of North Atlantic fin whales over four decades of varying environmental conditions. ICES Journal of Marine Science, 70(6), 1273-1280. https://doi.org/10.1093/icesjms/fst059

Witteveen, B. H., Worthy, G. A. J., Foy, R. J., & Wynne, K. M. (2011). Modeling the diet of humpback whales: An approach using stable carbon and nitrogen isotopes in a Bayesian mixing model. Marine Mammal Science, 28(3), 1-18. https://doi.org/10.1111/j.1748-7692.2011.00508.x

Zupcic-Moore, J. R., Ruiz-Cooley, R. I., Paliza, O., Koch, P. L., & McCarthy, M. D. (2017). Using stable isotopes to investigate foraging variation and habitat use of sperm whales from northern Peru. Marine Ecology Progress Series, 579, 201-212. https://doi.org/10.3354/meps12281

Long-term stability in the circumpolar foraging range of a Southern Ocean predator between the eras of whaling and rapid climate change