Research
My work focuses on connecting ocean conditions to the behavior and success of marine mammal populations. I am particularly interested in individual variability in behavior, what drives and maintains that variability, and what the ecological consequences are for a population.
I have had the privilege and opportunity to work with several different pinniped species on topics ranging from cellular-level physiology to species-level behavior and ecology. Currently, I am part of a collaborative effort to assess the consequences of multiple stressors on northern elephant seals. We are evaluating the interacting effects of acoustic disturbance, contaminant load, varying foraging conditions, and acute physiological stress responses on reproductive success.
Recent Publications
First observations of sponge foraging by Weddell seals in Erebus Bay, Antarctica
Other Publications
Peterson, S.E., J.T. Ackerman, R.R. Holser, B.I. McDonald, D.P. Costa, D.E. Crocker. 2023. Multiple stressors interact in a free-ranging marine mammal: mercury bioaccumulation and cortisol influence endocrine and immune biomarkers. Environmental Science and Technology
Adachi, T., P. Lovell, J. Turnbull, M. Fedak, B. Picard, C. Guinet, M. Biuw, T. Keates, R.R. Holser, D.P. Costa, D.E. Crocker, and P. Miller. 2023. Body condition changes at sea: onboard calculation and telemetry of body density in diving animals. Methods in Ecology and Evolutiom
Keates, T.R., E.L. Hazen, R.R. Holser, J. Fiechter, S.J. Bograd, P.W. Robinson and D.P. Costa. 2022. Foraging behavior of a mesopelagic predator in northeastern Pacific eddies. Deep Sea Research Part I: Oceanographic Research Papers
Holser, R.R., T.R. Keates, D.P. Costa, C.A. Edwards. 2022. Extent and Magnitude of Subsurface Anomalies During the Northeast Pacific Blob as Measured by Animal-Borne Sensors. J. Geophys. Res.: Oceans.
Costa, D.P., & R.R. Holser. 2022. Animal personality: Worn whiskers reveal resilience. Current Biology, 32(11), R528-R530
Adachi, T., Y. Naito, P.W. Robinson, D.P. Costa, L.A. Hückstädt, R.R. Holser, W. Iwasaki, & A. Takahashi. 2022. Whiskers as hydrodynamic prey sensors in foraging seals. Proc. Nat. Acad. Sci.
Kendall-Bar, JM; R Mukherji; J Nichols; C Lopez; DA Lozano; JK Pitman; RR Holser; RS Beltran;
M Schalles; CA Field; SP Johnson; AL Vyssotski; DP Costa; TM Williams. 2022. Eavesdropping on the brain at sea: development of a surface-mounted system to detect weak electrophysiological signals from wild animals. Animal Biotelemetry
Harcourt, R, MA Hindell, CR McMahon, KT Goetz, JB Charrassin, K Heerah, RR Holser, ID Jonsen, MR Shero, X Hoenner, R Foster, B Lenting, E Tarszisz, MH Pinkerton. 2021. Regional Variation in Winter Foraging Strategies by Weddell Seals in Eastern Antarctica and the Ross Sea. Front. Mar. Sci.
Adachi, T, A Takahashi, DP Costa, PW Robinson, LA Huckstadt, SH Peterson, RR Holser,
RS Beltran, TR Keates, Y Naito. 2021. Forced into an ecological corner: Round-the-clock deep foraging on small prey by elephant seals. Science Advances
Khudyakov, JI, RR Holser, CA Vierra, ST Ly, TK Niel, BM Hasan, DE Crocker, DP Costa. 2022. Changes in apolipoprotein abundance dominate proteome responses to prolonged fasting in the northern elephant seal. Journal of Experimental Biology, 225(4).
Holser, R.R., D.E. Crocker, R. Condit, P.W. Robinson, D.P. Costa. 2021. Density-dependent effects on reproductive output in a capital breeding carnivore, the northern elephant seal (Mirounga angustirostris). Proceedings of the Royal Society: B