Default Avatar

Kathryn A. Ono, Ph.D.

Professor Emeritus


Biddeford Campus




University of California, Santa Cruz
University of California, Davis
Ph.D. Zoology
University of California, Davis


  • Animal behavior
  • Conservation biology
  • Marine mammal biology
  • Zoology

Post-Doctoral Training

Post-Doctoral Training: National Zoological Park, Washington D.C.


Current research

Initiating studies on the behavior of grey seals (Halichoerus grypus) in Maine; studies on the diving behavior of harbor seal pups.

Selected publications

McCosker C, Flanders K, Ono K, Dufault M, Mellone D, and Olson Z. 2020. Metabarcoding fecal DNA reveals extent of Halichoerus grypus (gray seal) foraging on invertebrates and incidence of parasite exposure.  Northeastern Naturalist 27: 681-700.

Dufault M, Olson Z, Mellone D, Flanders K, and Ono K. 2021. Flatfish may be underestimated in the diet of grey seals (Halichoerus grypus). Canadian Journal of Zoology 99(3): 227-234

Flanders K, Olson Z, and Ono K. 2020.  Utilizing next-generation sequencing to identify prey DNA in western North Atlantic grey seal Halichoerus grypus diet. Marine Ecology Progress Series 655: 227-240.

Lerner J.E., Ono, K., Hernandez, K.M., Runstadler, J.A., Puryear, W., and Polito M.J. (in review). Evaluating the use of stable isotope analysis to infer the feeding ecology of a growing US gray seal (Halichoerus grypus) population. PLoS ONE.

Ono, K.A. Steinbeiser, C.M., Coco, A.B., Sheehan, M.J., Beck, A.J, Dufault, M.N., Gilbert, K.M., Antonez, J.J., Olson, Z.H. (in review).  Detecting spiny dogfish in grey seal diets.  Conservation Genetics Resources

A Thomas, K Ono. 2015,  Diving related changes in the blood oxygen stores of rehabilitating harbor seal pups (Phoca vitulina).  PLOSone: DOI:10.1371/journal.pone.0128930

Takeuchi, N.Y., D.S. Barber, K.A. Ono.  2011.  Circulating retinol and alpha-tocopherol levels in rehabilitating harbor seal (Phoca vitulina) pups.  J. Wildlife Rehab. 31(3): 15-22

Masland, E.D.P., M.A. Sweezy, K.A. Ono.  2010.  Molecular methods for differentiating grey seal (Halichoerus grypus) and harbour seal (Phoca vitulina) scat.  Molecular Ecology Resources 10: 214-217

Hood, W. R., and K. A. Ono.  1997.  Variation in maternal attendance patterns and pup behavior in a declining population of Steller sea lions (Eumetopias jubatus).  Can. J. Zoology 75: 1241-1246.

Ono, K. A.  1997.  Sea lions, life history and reproduction.  In: The Evolving Female:  A Life-      History Perspective, eds. M. E. Morbeck, A. Galloway, and A. L. Zihlman.  Princeton University Press:  Princeton, NJ, pgs. 34-45.

 Westlake, R. L., Perryman, W. L., and Ono, K. A.  1997.  Comparison of       vertical aerial photographic and ground censuses of Steller sea lions at Año Nuevo Island, July 1990-1993.  Mar. Mamm. Sci. 13: 207-218.

Ono, K. A., and D. J. Boness.  1996.  Sexual size dimorphism in California sea lion pups:  Differential maternal investment or sexual differences in energy allocation? Behav. Ecology and Sociobiology 38: 31-41.

Ono, K.A.  1995. Effects of climate change on marine mammals in the far North.  In:  Human Ecology and Climate Change:  People and Resources in the Far North, ed. D. L. Peterson and D. R. Johnson.  Washington, DC:  Taylor and Francis, pgs. 105-121.

Ono, K. A., D. J. Boness, O. T. Oftedal, S. J. Iverson.  1993.  The effects of El Niño on mother-pup biology in the California sea lion.  In:  Third California Islands Symposium:  Recent Advances in Research on  the California  Islands., ed. F. G. Hochberg.  Santa Barbara Museum of Natural History:  Santa Barbara, CA.  pp. 495-499.

1991.  Pinnipeds and El Niño:  Responses to Environmental Stress.  F. Trillmich and K. A. Ono, editors, Springer-Verlag.  293 pp.

Comparison of Health and Behavior Parameters in Rehabilitated Stranded and Wild Harbor Seal Pups (Phoca vitulina concolor), an EPA grant to study to study pathogens, diving and movements of harbor seal pups in Maine.

Location-specific diving behavior of Harbor seal (Phoca vitulina) pups, a CAS mini-grant to study feeding behavior in wild harbor seal pups.  



Research interests

Behavioral ecology of pinnipeds (seals and sea lions); diving behavior and life history studies in seals; breeding behavior of pinnipeds; reproductive biology of pinnipeds.