Cetacean Behavior
Studying oceanic cetacean societies: their diversity, complexity, and conservation.

Studies of cetacean behavior provide information on social organization, social signals, mating systems, and anthropogenic impacts. The goal of these studies is to provide a social framework within which to investigate questions about stock identity, population trends, and fishery interactions. The cetacean behavior studies reflect the interests and expertise of many researchers in the Marine Mammal and Turtle Division. We use a variety of tools and work in collaboration on a number of different questions related to cetacean societies and social living in the open ocean.
Cetacean Social Structure
Within the Marine Mammal Genetic Group, researchers work on a number of projects that use molecular techniques to document the social organization, social structure and sex-biased dispersal patterns of wild cetaceans. There are studies on several species, including sperm whales, Dall's porpoises, eastern tropical Pacific dolphins, belugas, killer whales, pilot whales, and gray whales.
Cetacean Sexual Ecology
We work on a suite of comparative studies of cetacean mating systems based morphological characters, including relative testes size and sperm competition theory, female reproductive tract anatomy, and sexual dimorphism. We are interested in both intraspecific variation (in spinner dolphins) and interspecific variation and the evolution of cetacean mating systems. This is a project in collaboration with Dara Orbach, Texas A&M.
Cetacean Conservation Behavior
We are interested in understanding the relationship between cetacean behavior, culture and sociality and population-level response to exploitation and social disruption by human activities. The work is both comparative and field based. Field work focuses on variation in dolphin behavior in several stocks of eastern tropical Pacific dolphins involved in the tuna purse-seine fishery. In these studies, we are interested in the application of new statistical methods to determine predictors of dolphin behavior and the potential impacts of social disruption caused by fishing operations on dolphin population trends.
Cetacean Acoustics: Biogeographic Variation in Blue Whale Song
We are interested in biogeographic variation in acoustic signals and the use of acoustic signals as indicators of population identify. These projects focus on blue whale acoustics, in collaboration with Mark McDonald and John Hildbrand at Scripps Institution of Oceanography, UC San Diego. Our focus has been on global variation in blue whale song and, more recently, the discovery of a global decrease in the pitch of blue whale song.
Behavioral Ecology of Killer Whales
We collaborate with other researchers within the Marine Mammal and Turtle Division on investigations of killer whale behavior, ecology, and evolution and how the risk of predation by mammal eating killer whales influences the behavior and ecology of other cetacean species. In the eastern tropical Pacific, we investigate the genetic structure of killer whale groups.
Human-Wildlife Conflict: Depredation in Sperm Whales
Depredation, the taking of hooked prey from fishing gear, is a growing, global phenomenon in cetaceans. We use a social learning approach to understand the dynamics of human-wildlife conflict, with a focus on sperm whale depredation in Southeast Alaska. This a project in collaboration with Jan Straley at the University of Alaska, SEASWAP, the Alaska Fisheries Science Center, and Zach Schackner (a graduate student at UC Los Angeles at the time).
Project Lead
For additional information, contact sarah.mesnick@noaa.gov
Selected References
Orbach DN, Brennan PL, Hedrick BP, Keener W, Webber MA, Mesnick SL. 2020. Asymmetric and Spiraled Genitalia coevolve with Unique Lateralized Mating Behavior. Scientific Reports. 10(1):1-8.
Brakes P, Dall SR, Aplin LM, Bearhop S, Carroll EL, Ciucci P, Fishlock V, Ford JK, Garland EC, Keith SA, McGregor PK. 2019. Animal cultures matter for conservation. Science. 363(6431):1032-4.
Berger‐Tal O, Blumstein DT, Carroll S, Fisher RN, Mesnick SL, Owen MA, Saltz D, St Claire CC, Swaisgood RR. 2016. A systematic survey of the integration of animal behavior into conservation. Conservation Biology. 30(4):744-53.
Dines JP, Mesnick SL, Ralls K, May‐Collado L, Agnarsson I, Dean MD. 2015. A trade‐off between precopulatory and postcopulatory trait investment in male cetaceans. Evolution. 69(6):1560-72.
Schakner ZA, Lunsford C, Straley J, Eguchi T, Mesnick SL. 2014. Using models of social transmission to examine the spread of longline depredation behavior among sperm whales in the Gulf of Alaska. PLoS One.9(10):e109079.
Caro T, Stankowich T, Mesnick SL, Costa DP, Beeman K. 2012. Pelage coloration in pinnipeds: functional considerations. Behavioral Ecology. 23(4):765-74.
Rendell L, Mesnick SL, Dalebout ML, Burtenshaw J, Whitehead H. 2012. Can Genetic Differences Explain Vocal Dialect Variation in Sperm Whales, Physeter macrocephalus? Behavior genetics. 42(2):332-43.
Archer FI, Mesnick SL, Allen AC. 2010. Variation and predictors of vessel-response behavior in a tropical dolphin community. NOAA Technical Memorandum NMFS NOAA-TM-NMFS-SWFSC-457. 54 pp.
McDonald MA, Hildebrand JA, Mesnick S. Worldwide decline in tonal frequencies of blue whale songs. Endangered species research. 2009 Oct 23;9(1):13-21.
Mesnick, S.L. and Ralls, K. 2008. Mating Systems. In, Encyclopedia of Marine Mammals, Second Edition (eds., W.F. Perrrin, H.G.M. Thewissen and B. Würsig). Academic Press, San Diego. Pages 712-719.
Ralls, K. and Mesnick, S.L. 2008. Sexual Dimorphism. In, Encyclopedia of Marine Mammals, Second Edition (eds., W.F. Perrrin, H.G.M. Thewissen and B. Würsig). Academic Press, San Diego. Pages 1005 – 1011.
Rubio-Cisneros, N.., Mesnick, S.L., Vázquez-Juárez, R.., Urbán-Ramírez, J., Godard, C.A.J., Payne, R.. and Dizon, A.E. 2007. Genetic sex determination supports the Gulf of California as an important habitat for male and female sperm whales (Physeter macrocephalus). Latin American Journal of Aquatic Mammals 5(2): 125-128.
McDonald, M.A., Mesnick, S.L. and Hildebrand, J.A. 2006. Biogeographic characterization of blue whale song worldwide: using song to identify populations. Journal of Cetacean Research and Management 8: 55-65.
Allen, A., Mesnick, S.L., Anderson, M., and Dixson, A. 2003. Phylogenetic analysis of testes size in odontocete cetaceans. Abstract presented at the 15th Biennial Conference of the Marine Mammal Society. Greensboro, North Carolina, December 2003.
Bonness, D., Clapham, P.J. and Mesnick, S.L. 2002. Life History and Reproductive Strategies. In,Marine Mammals: An Evolutionary Approach (ed., R. Hoelzel).Blackwell Science, Ltd. Pp. 278-324.
Escorza-Trevino, S., and A.E. Dizon. 2000. Phylogeography, intraspecific structure, and sex-biased dispersal of Dall's porpoise, Phocoenoides dalli, revealed by mitochondrial and microsatellite DNA analysis. Molecular Ecology 9:1049-1060.
Mesnick, S.L., Evans, K. Taylor, B.L., Hyde, J., Escorza-Trevino, S and Dizon, A.E. 2003. Sperm Whale Social Structure: Why it Takes a Village to Raise a Child. Pages 170-174, In, Animal Social Complexity: Intelligence, Culture and Individualized Societies (F.B.M. de Waal and P.L. Tyack, eds.). Harvard University Press
Mesnick, S.L. 2001. Genetic Relatedness in Sperm Whales: Evidence and Cultural Implications. Behavior and Brain Science 24(2):346-347
Mesnick, S.L., Clapham, P.J. and Dizon, A.E. 1999. The Collection of Associated Behavioral Data with Biopsy Samples during Cetacean Assessment Cruises. Journal of Cetacean Research and Management 1(2): 205-211
Mesnick, S. L., Taylor, B.L., Le Duc, R.G., Escorza Trevino, S., O'Corry-Crowe, G.M. and Dizon, A.E. 1999. Culture and Genetic Evolution in Whales. Science, 284: 2055a
O'Corry-Crowe GM, Suydam RS, Rosenberg A et al. (1997) Phylogeography, population structure and dispersal patterns of the beluga whale Delphinapterus leucas in the western Nearctic revealed by mitochondrial DNA. Molecular Ecology, 6, 955-970.
Perrin, W.F. and Mesnick, S.L. 2003. Sexual ecology of the spinner dolphin, Stenella longirostris:, geographic variation in mating system. Marine Mammal Science, 19(3):462-483
Pitman, R.L. 2003. Good whale hunting. Natural History December 2003/January 2004:24-28
Pitman, R.L., S. O'Sullivan, and B. Mase. In Press. Killer whales (Orcinus orca) attack a school of pantropical spotted dolphins (Stenella attenuata) in the Gulf of Mexico. Aquatic Mammals.
Pitman, R.L. and P. Ensor. 2003. Three different forms of killer whales in Antarctic waters. Journal of Cetacean Research and Management 5(2):131-139
Pitman, R.L., Ballance, L.T., Mesnick, S.L. and Chivers, S. 2001. Killer Whale Predation on Sperm Whales: Observations and Implications for Large Whale Biology. Marine Mammal Science: 17(3):494-507.
Pitman, R.L. and S.J. Chivers. 1998/1999. Terror in black and white. Natural History 107:26-29.