Our research currently focuses with our collaborators on mercury concentrations and stable isotope signatures in seals and sea lions and their prey to help understand how heavy metals move within ecosystems and how they may impact conservation of piscivorous marine mammal species. We also focus on assessment of diet composition using stable isotopes, body condition and general health assessment of marine wildlife, and adaptive biochemistry and metabolism in fasting marine mammals.
Ocean Peace Research Partnership III
L.D. Rea. $300,000. Ocean Peace, Inc. through the UA Foundation. January 2021 – December 2022
Phocid whisker stable isotopes
L.D. Rea $82,000. NOAA NFFS7300-20-02650 (contract 1305M320PNFFS0633). September 2020-September 2021
Collaborative Research: Mercury dynamics from the Holocene to the Anthropocene: Tracking Aleutian mercury in ocean species important to Native Alaskan diets
J.P. Avery, N. Misarti, L.D. Rea and C.L. Funk. $2,621,196. National Science Foundation, Office of Polar Programs, Arctic System Science and Arctic Social Science. May 2020 – December 2024
Ocean Peace Research Partnership II
L.D. Rea. $300,000. Ocean Peace, Inc. through the UA Foundation. January 2020 – December 2021
A novel coupling of isotopic approaches to identify pathways of methylmercury through marine food-webs of the Aleutians
B. Barst (PI), M. Wooller, L.D. Rea (Co-I), and T.M. O’Hara. North Pacific Research Board $437,997. September 2019 – August 2022
Modeling diet composition of adult female Steller sea lions from the western and central Aleutian Islands
L.D. Rea (PI), T. O’Hara, B. Taras and M. Wooller. $1,016,733. NOAA 2019 Alaska Pinniped Research Program (NOAA-NMFS-AK-2019- 2005923). July 2019 – June 2022
Methane in the Marine Environment: Sources and Potential Adverse Effects (Marine Methane Fellowship)
T.M. O’Hara, J. Guerard, L.D. Rea, S. Aggarwal. $290,000. Hilcorp Alaska, LLC. January 2019- December 2021
Wildlife health and contaminant levels on St. Paul Island, AK
L.D. Rea. $54,079.00 NIH BLaST Program, UAF. September 2017 – June 2019
Tracing pathways of mercury exposure to Alaska pinnipeds in the Aleutian Islands and the Bering Sea
L.D. Rea (PI), T. O’Hara (Co-I), M. Wooller (Co-I), B. Taras (Co-I). $1,121,891. NOAA 2016 Alaska Pinniped Research Program (NOAA-NMFS-AK-2016-2004624). July 2016 – June 2019.
Adverse effects of contaminants in Steller sea lions: Immune and Oxidative Stress Status
T.M. O’Hara (PI), L.D. Rea (Co-PI), T. Kuhn (Co-I), T. Zenteno-Savin (Consultant). $546,291. NOAA 2016 Alaska Pinniped Research Program (NOAA-NMFS-AK-2016-2004624). July 2016 – June 2019
Are contaminant concentrations in young Steller sea lions in the Western Aleutian Islands associated with altered endocrine and immune systems?
R. Small (PI), M. Keogh (Co-I and Project Manager), S. Karpovich (Co-I), M. Levin (Co-I), T.M. O’Hara (Co-I), L.D. Rea (Co-I), J. Maniscalco (Co-I). $839,080. NOAA 2016 Alaska Pinniped Research Program funding to ADF&G (NOAA-NMFS-AK-2016-2004624). April 2016- July 2019
Foraging movements and diving behavior of “resident”-type killer whales in the western and central Aleutian Islands – are killer whales competing with Steller sea lions and commercial fisheries as an important consumer of Atka mackerel?
L.D. Rea (PI) and P.R. Wade (Co-I). $99,717. Pollock Conservation Cooperative Research Center (PCCRC) at University of Alaska Fairbanks. April 2016 – March 2019.
2024
Bishop AM, Barst BD, Rea LD (2024) Foraging niche, sex-specific resource partitioning, and mercury concentrations of male Steller sea lions in Alaska. Marine Ecology Progress Series 736:147–165.
Crawford SG*, Coker RH, Rea LD (2024) Preliminary comparisons between a point-of-care ketometer and reference method using Steller sea lion pup whole blood and plasma. Conservation Physiology 12(1), coad104.
Keenan MP*, Misarti N, Horstmann L, Crawford SG, O’Hara T, Rea LD, Avery JP (2024) Total mercury concentrations in Steller sea lion bone: variability among locations and elements. Marine Pollution Bulletin 203, 116471.
Trifari MP*, Wooller MJ, Rea L, O'Hara TM, Lescord GL, Parnell AC, Barst BD (2024) Compound-specific stable isotopes of amino acids reveal influences of trophic level and primary production sources on mercury concentrations in fishes from the Aleutian Islands, Alaska. Science of The Total Environment 15:908:168242.
2023
Avery JP, Castellini JM, Misarti N, Keenan M*, Gastaldi A, Funk C, O’Hara TM, Rea LD (2023) Evaluating methods for determining mercury concentrations in ancient marine fish and mammal bones as an approach to assessing millennial-scale fluctuations in marine ecosystem. Frontiers in Ecology and Evolution 11.
Crawford SG*, Coker RH, O’Hara TM, Breed G A, Gelatt T, Fadely B, Burkanov V, Rivera PM, Rea, LD (2023) Fasting durations of Steller sea lion pups vary among subpopulations - evidence from two plasma metabolites. Conservation Physiology 11(1): 1–24.
Funk C, Lackos H, Misart, N, Rea L, Avery J (2023) Considering ancestral Unangam selection biases in transdisciplinary research. Alaska J of Anthropology 21(1-2).
Gastaldi A, Bishop A, Rea LD (2023) How small can you go? Using a direct mercury analyzer to measure mercury in vibrissae of Steller sea lions. Marine Mammal Science 39(3): 1005–1010.
2022
Castellini JM, Rea LD, Avery JP, O'Hara TM (2022), Total mercury, total selenium, and monomethylmercury relationships in multiple age cohorts and tissues of Steller sea lions (Eumetopias jubatus). Environmental Toxicology and Chemistry 41:1477-1489.
2021
Kennedy SN*, Keogh M, Levin M, Castellini JM, Lian M, Fadely B, Rea LD, O’Hara TM (2021) Regional variations and relationships among cytokine profiles, white blood cell counts, and blood mercury concentrations in Steller sea lion (Eumetopias jubatus) pups. Science of the Total Environment 144894.
Keogh MJ, Charapata P, Fadely BS, Zeppelin T, Rea L, Waite JN, Burkanov V, Marshall C, Jones A, Sprowls C (2021) Whiskers as a novel tissue for tracking reproductive and stress-related hormones in North Pacific otariid pinnipeds. Conservation Physiology 9(1):coaa134.
Lian M*, Field CL, van Wijngaarden E, Rios C, Castellini JM, Greig DJ, Rea LD, Coleman DJ, Thomson, CE, Gulland, FMD (2021) Assessment of clinical outcomes associated with mercury concentrations in harbor seal pups (Phoca vitulina richardii) in central California. Science of the Total Environment 758:143686.
2020
Keogh MJ, Taras B, Beckmen KB, Burek-Huntington KA, Ylitalo GM, Fadely BS, Rea LD, Pitcher KW (2020) Organochlorine contaminant concentrations in blubber of young Steller sea lion (Eumetopias jubatus) are influenced by region, age, sex, and lipid stores. Science of the Total Environment 698: 134183.
Levin M, Jasperse L, Desforges JP, O’Hara T, Rea L, Castellini JM, Maniscalco JM, Fadely B, Keogh M (2020) Methyl mercury (MeHg) in vitro exposure alters mitogen-induced lymphocyte proliferation and cytokine expression in Steller sea lion (Eumetopias jubatus) pups. Science of the Total Environment 725.
Lian M*, Castellini JM, Kuhn T, Rea L, Bishop L, Keogh M, Kennedy SN, Fadely B, van Wijngaarden E, Maniscalco JM, O’Hara T (2020) Assessing oxidative stress in Steller sea lions (Eumetopias jubatus): Associations with mercury and selenium concentrations. Comparative Biochemistry and Physiology Part - C: Toxicology and Pharmacology 235.
Rea LD, Castellini JM, Avery JP, Fadely BS, Burkanov VN, Rehberg MJ, O’Hara TM (2020) Regional variations and drivers of mercury and selenium concentrations in Steller sea lions. Science of the Total Environment 744:140787. 2019
Cyr A*, Lopez JA, Rea L, Wooller MJ, Loomis T, McDermott S, O’Hara TM (2019) Mercury concentrations in marine species from the Aleutian Islands: Spatial and biological determinants. Science of the Total Environment 664:761–770.
Kennedy SN*, Castellini JM, Hayden AB, Fadely BS, Burkanov VN, Dajles A, O’Hara TM, Rea, LD (2019) Regional and Age-Related Variations in Haptoglobin Concentrations in Steller Sea Lions (Eumetopias jubatus) from Alaska. USA Journal of Wildlife Disease 55(1):91–104.
Keogh MJ, Taras BD, Eischens C, Kennish JM, Fadely BS, Rea LD (2019) Variation in milk, serum, and blubber fatty acids in young, free-ranging Steller sea lions. Marine Mammal Science 35(3).
2018
Doll AC, Taras BD, Stricker CA, Rea LD, O’Hara TM, Cyr AP*, Mcdermott S, Loomis TM, Wunder MB (2018) Temporal records of diet diversity dynamics in individual adult female Steller sea lion (Eumetopias jubatus) vibrissae. Oecologia 188:263-75.
Kennedy SN*, Wilhite B, Castellini JM, Rea LD, Kuhn TB, Ferrante A, O’Hara TM (2018) Enhanced quantification of serum immunoglobulin G from a non-model wildlife species, the Steller sea lion (Eumetopias jubatus), using a protein A ELISA. Journal of Immunological Methods 462.
Lian* M, Johnson S, Gelatt TS, O’Hara TM, Beckmen KB, Rea LD (2018) Field anesthesia of juvenile Steller sea lions (Eumetopias jubatus) using inhalation anesthesia. Marine Mammal Science 34(1):125–135.
Rehberg MJ, Rea LD, Eischens CA (2018) Overwintering Steller sea lion (Eumetopias jubatus) pup growth and behavior prior to weaning. Canadian Journal of Zoology 96:97–106.
2015-17
O’Hara TM, Hueffer K, Murphy M, Castellini JM, Li Y, Rea LD, Berner J (2017) Developing a Sentinel-based Baja California Sur Rural Mexico Monitoring Program (BCS RMMP): Lessons learned from Alaska. Recursos Naturales y Sociedad 3(2):12-31.
Pendleton GW, Hastings KK, Rea LD, Jemison LA, O’Corry-Crowe GM, Beckmen KB (2016) Short-term survival of Steller sea lion (Eumetopias jubatus) pups: Investigating the effect of health status on survival. Marine Mammal Science 32(3):931-944.
Peterson SH*, McHuron EA*, Kennedy SN*, Ackerman JT, Rea LD, Castellini JM, O'Hara TM, Costa DP (2016) Evaluating hair as a predictor of blood mercury: the influence of ontogenetic phase and life history in pinnipeds. Archives of Environmental Contaminants Toxicology Special Issue: New Developments and Perspectives in Marine Mammal Toxicology 70:28-45.
Rea LD, Christ AM, Hayden AB, Stegall AK*, Farley SD, Stricker CA, Mellish JE, Maniscalco JM, Waite JN, Burkanov V, Pitcher KW (2015) Age-specific vibrissae growth rates: A tool for determining the timing of ecologically important events in Steller sea lions. Marine Mammal Science 31(3):1213-1233.
Rea LD, Fadely BS, Farley SD, Avery JP, Dunlap-Harding WS, Stegall V, Eischens CAB, Gelatt TS, Pitcher KW (2016) Comparing total body lipid content of young-of-the-year Steller sea lions between areas of contrasting population trends. Marine Mammal Science 32(4):1200-1218.
Scherer RD, Doll AC*, Rea LD, Christ AM, Stricker CA, Witteveen B, Kline TC, Kurle CM, Wunder MB (2015) Isotope values in pup whiskers reveal geographic variation in diets of gestating Steller sea lions (Eumetopias jubatus). Marine Ecology Progress Series 527:261-274.
Stricker CA, Christ AM, Wunder MB, Doll AC*, Farley SD, Rea LD, Rosen DAS, Scherer RD, Tollit DJ (2015) Carbon and nitrogen isotope discrimination for Steller sea lion (Eumetopias jubatus) vibrissae relative to milk and fish/invertebrate diets. Marine Ecology Progress Series 523:255-266.
