Brett Jesmer, shown here on a GPS collaring expedition in the Wyoming Range of western
Wyoming, is the winner of the 2019 George Mercer Award from the Ecological Society
of America. His UW Ph.D. study was the first to show empirically that ungulates learn
to migrate over time and pass this cultural behavior to subsequent generations through
social learning. (Brendan Oates Photo)
Big-game migration research led by a recent University of Wyoming Ph.D. graduate has
received national recognition from the Ecological Society of America. The research
provided the first empirical evidence that ungulates (hooved mammals) must learn where
and when to migrate -- and that they maintain their seasonal migrations by passing
cultural knowledge across generations.
The study, led by Brett Jesmer during his doctoral studies in ecology at UW, is the
winner of the 2019 George Mercer Award from the Ecological Society of America (ESA).
The award recognizes an outstanding, recently published, ecological research paper
by young scientists. The paper appeared in the journal Science in September. Jesmer, who graduated from UW in 2018, is now a postdoctoral researcher
at Yale University.
“Jesmer and colleagues compared migration of historical and translocated populations
of bighorn sheep and moose, demonstrating that ungulate migration is inherited culturally
rather than genetically,” the ESA says in a media release announcing the honor. “This
creative and interdisciplinary work represents a strong collaboration between researchers
in academia and wildlife managers from state agencies, demonstrating that behavioral
ecology provides an important foundation for pressing ecological and management questions.”
The award will be presented at the ESA’s annual meeting in August in Louisville, Ky.
The full list of authors on the paper also includes UW researchers Jerod Merkle, Jacob
Goheen, Ellen Aikens, Jeffrey Beck, Kevin Monteith and Matthew Kauffman; Wyoming Game
and Fish Department biologists Alyson Courtemanch and Douglas McWhirter; and Idaho
Department of Fish and Game biologists Mark Hurley and Hollie Miyasaki.
Biologists have long suspected that, unlike many bird, fish and insect migrations
that are driven by genetics, ungulates learn to migrate from their mothers or other
animals in the herd. Previous research had hinted that migration was socially learned
in ungulates, but a clear test had eluded researchers.
This study looked at behavior of bighorn sheep across the American West and found that fewer
than 9 percent of animals that been translocated to re-establish sheep herds migrated,
while 65 to 100 percent of animals migrated in herds that had never been lost. Translocated
animals did not migrate because they were unfamiliar with their new habitats, supporting
the notion that migration requires extended periods for animals to explore, learn
the location of nutritious food and pass that information on to other herd members,
including their offspring.
The researchers also used GPS collar tracking data from 267 bighorn sheep and 189
moose -- some that had just been released in unfamiliar landscapes, others that had
occupied their ranges for decades or even centuries -- and found that long-established
herds were better at finding nutritious food than animals translocated to unfamiliar
landscapes.
“These results indicate that ungulates accumulate knowledge of their landscapes over
time, and cultural transmission of this knowledge is necessary for migrations to arise
and persist,” Jesmer says.
The study is unique in indicating that habitat quality is best imagined as the physical
landscape that animals occupy, in combination with the knowledge they have accumulated
about how to use that landscape. That finding has important implications for the conservation
of migration corridors, says Kauffman, one of Jesmer's doctoral advisers and a wildlife
researcher with the U.S. Geological Survey's Wyoming Cooperative Fish and Wildlife
Research Unit at UW.
