The zoo is open! All visitors will require free entry passes and be required to follow safety measures. Free timed-entry Asia Trail/Panda Passes are required for the giant panda viewing.

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Katherine Ralls, Ph.D.

Senior Research Zoologist Emerita
B.A., Stanford University; M.S., Radcliffe College; Ph.D., Harvard University

Katherine Ralls is a mammalogist and conservation biologist emerita at the Smithsonian Conservation Biology Institute's Center for Conservation Genomics. She was one of the first scientists hired at the Smithsonian's National Zoo and was one of the founders of the Society for Conservation Biology. Ralls studies the behavioral ecology, genetics and conservation of terrestrial and marine mammals. She has conducted field studies of sea otters, San Joaquin kit foxes and island foxes.

Ralls' research interests include:

  • Genetic management of small captive and wild populations
  • Behavioral ecology, genetics and conservation of mammals
  • Field studies of sea otters and foxes
  • Sexual dimorphism, mating systems, scent marking and tool-use
Ralls' early papers on scent marking and sexual dimorphism have been widely cited. Her pioneering work on inbreeding problems in zoo animals, along with SCBI’s Jon Ballou, led to the genetic and demographic management of captive populations now practiced in zoos worldwide. Most recently, Ralls and Ballou were among the co-authors of the first textbook on the genetic management of fragmented wild animal and plant populations.
Ralls did her undergraduate work at Stanford University. She earned her master's degree at Radcliffe College and her doctorate in biology at Harvard University. Ralls was the 1996 recipient of the American Society of Mammalogist's C. Hart Merriam Award and the Society for Conservation Biology's Edward T. LaRoe Award. In 2006, she was named an Honorary Fellow of the Zoological Society of London, and in 2015 she was named an Honorary Member of the American Society of Mammalogists.
Recent Publications: 
Crooks, Kevin R., Mills, L. Scott, Sanjayan, M., Ehrlich, Paul R., Ogden, John C., Allendorf, Fred W., Ralls, Katherine, Noss, Reed F., Mace, Georgina, Estes, James A., Doak, Daniel F., Terborgh, John and Inouye, David W. 2020. Reflections on Michael Soule, a visionary for conservation biology. Conservation Biology. https://doi.org/10.1111/cobi.13597
Ralls, Katherine, Sunnucks, Paul, Lacy, Robert C. and Frankham, Richard. 2020. Genetic rescue: A critique of the evidence supports maximizing genetic diversity rather than minimizing the introduction of putatively harmful genetic variation. Biological Conservation, 108784-108784. https://doi.org/10.1016/j.biocon.2020.108784
Brownell, Robert L., Jr., Reeves, Randall R., Read, Andrew J., Smith, Brian D., Thomas, Peter O., Ralls, Katherine, Amano, Masao, Berggren, Per, Chit, Aung Myo, Collins, Tim, Currey, Rohan, Dolar, M. Louella L., Genov, Tilen, Hobbs, Roderick C., Kreb, Danielle, Marsh, Helene, Zhigang, Mei, Perrin, William F., Phay, Somany, Rojas-Bracho, Lorenzo, Ryan, Gerry E., Shelden, Kim E. W., Slooten, Elisabeth, Taylor, Barbara L., Vidal, Omar, et al. 2019. Bycatch in gillnet fisheries threatens Critically Endangered small cetaceans and other aquatic megafauna. Endangered Species Research, 285-296. https://doi.org/10.3354/esr00994