Contact Information
Institute of Marine Science232 Irving II
P.O. Box 757220
University of Alaska Fairbanks
Fairbanks, AK 99775-7220
Phone: (907) 474-7724
Fax: (907) 474-7204
lara.horstmann@alaska.edu
Lara Horstmann-Dehn Assistant Professor
Education
- M.S. 1997 University of Kiel (Zoology)
- Ph.D. 2005 University of Alaska Fairbanks (Biology)
Office Hours
Tuesday and Thursday 10:00-11:30Research Overview
I am interested in broad-scale marine mammal ecology. Feeding ecology in particular is a keystone piece of information to understand adaptation potential of marine mammals and challenges that may arise. Dietary limitations can affect reproductive success, compromise immune function, change exposure to new pathogens (i.e., parasites, contaminants), and can therefore not only limit marine mammal population growth, but also potentially introduce new threats to humans depending on them as a subsistence resource.
I focus my research on Arctic marine mammals, because 1) they are of cultural and nutritional importance to subsistence users, 2) the Arctic is undergoing noticeable change, and 3) planned oil and gas development in this habitat
I am also working on a fish parasite, Ichthyophonus hoferi, in Chinook salmon, and its potential impact on pre-spawning mortality and fecundity
Current Research Projects
- Freshwater growth and survival in AYK Chinook salmon: maternal influences, predation mortality, and the ultimate effects on stock productivity
- Bowhead whale feeding in the western Beaufort Sea (BOWFEST)
- Disease severity and ties to Chinook salmon ecological and physiological parameters in the marine migration phase
- Tracking the seasonal contribution of algal fatty acids to the arctic marine system
- Trophic links of forage fishes and ice seals in the Chukchi Sea
- Ichthyophonus in Yukon River Chinook salmon
- Trichinellosis in Pacific walruses and ice seals
Publications
Carroll, S.S., Horstmann-Dehn, L., Norcross, B.L. in review. Interannual variations in the diet of ice seals assessed by isotopic mixing models. Marine Mammal Science.
Horstmann-Dehn, L., Follmann, E.H., Rosa, C., Zelensky, G., George, C. 2011. Stable carbon and nitrogen isotope ratios in muscle and epidermis of Arctic whales. Marine Mammal Science. DOI: 10.1111/j.1748-7692.2011.00503.x
George, J.C., Follmann, E., Zeh, J., Sousa, M., Tarpley, R., Suydamn, R., Horstmann-Dehn, L. 2011. A new way to estimate the age of bowhead whales (Balaena mysticetus) using ovarian corpora counts. Canadian Journal of Zoology 89: 840-852.
Rosa, C., Blake, J.E., Bratton, G.R., Dehn, L-A., Gray, M.J., O’Hara, T.M. 2008. Heavy metal and mineral concentrations and their relationship to histopathological findings in the bowhead whale (Balaena mysticetus). Science of the Total Environment 399: 165-178.
George, J.C., Wetzel, D., O’Hara, T.M., Robertson, K., Dehn, L., Leduc, R., Reynolds, J. 2008. An analysis of ancient bowhead mangtak from Gambell Alaska: What can it tell us? SC/60/E2. 60th Meeting of the International Whaling Commission, Scientific Committee.
Kahler, E., Burton, T., Hamazaki, T., Borba, B.M., Jasper, J., Dehn, L.-A. (2007): Assessment of Ichthyophonus in Chinook salmon within the Yukon River Drainage, 2004. Alaska Department of Fish and Game, Fishery Data Series No. 07-64, Anchorage.
Dehn, L.-A., Sheffield, G. G., Follmann, E. H., Duffy, L. K., Thomas, D. L., O’Hara, T. M. (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 Biology 30, 167-181.
Dehn, L.-A., Follmann, E. H., Thomas, D. L., Sheffield, G. G., Rosa, C., Duffy, L. K., O’Hara, T. M. (2006): Trophic relationships in an Arctic food web and implications for trace metal transfer. Science of the Total Environment 362, 103-123.
Dehn, L.-A., Follmann, E. H., Rosa, C., Duffy, L. K., Thomas, D. L., Bratton, G. R., Taylor, R. J., O’Hara, T. M. (2006): Stable isotope and trace element status of subsistence-hunted bowhead and beluga whales in Alaska and gray whales in Chukotka. Marine Pollution Bulletin 52, 301-319.
Hughes-Hanks, J. M., Rickard, L. G., Panuska, C., Saucier, J. R., O’Hara, T. M., Dehn, L., Rolland, R. M. (2005): Prevalence of Cryptosporidium spp. and Giardia spp. in five marine mammal species. Journal of Parasitology 91, 1225-1228.
Dehn, L.-A., Sheffield, G. G., Follmann, E. H., Duffy, L. K., Thomas, D. L., Bratton, G. R., Taylor, R. J., O’Hara, T. M. (2005): Trace elements in tissues of phocid seals harvested in the Alaskan and Canadian Arctic – Influence of age and feeding ecology. Canadian Journal of Zoology 83, 726-746.
O’Hara, T. M., Hoekstra, P., Rosa, C., Dehn, L.-A., Woshner, V., Wise, J., Ylitalo, G., Wetzel, D., Bratton, G. (2004): Bowhead whale contaminants: A review of current state of knowledge and possible future directions. SC/56/E1. 56th Meeting of the International Whaling Commission (IWC SC).
Hoekstra, P. F., Dehn, L.-A., George, J. C., Muir, D. C. G., and O’Hara, T. M (2002): Trophic ecology of bowhead whales (Balaena mysticetus) compared with that of other arctic marine biota as interpreted from carbon-, nitrogen-, and sulfur-isotope signatures. Canadian Journal of Zoology 80, 223-231.
