Biologists release a pair of mother-daughter mule deer after processing them.

The ontogeny of ungulate migration

Each year, millions of ungulates migrate across seasonally changing landscapes. Some animals move to access forage that is only available during certain times during the year, whereas others migrate to reduce risk of predation and disease, and others still to escape unfavorable climactic conditions. These spBiologists release a pair of mother-daughter mule deer after processing them.ectacular migrations are rarely spontaneous movements in a randomly selected direction, but instead are continuations of behaviors that have been in place for years to millennia. Individual mule deer, for example, are extremely faithful to their migratory routes year after year, and rarely deviate from their migratory paths. Memory – whether within an individual or transmitted across individuals – likely plays a prominent role in ensuring that mule deer migrations continue year after year. Despite its central role in helping to maintain migration, we currently fail to understand how ungulates develop their memory pertaining to migration in the first place.


A close-up of a collared mule deer fawn.

In animals with extended maternal care, such as mule deer, an individual’s migratory behaviors could be established early in life. It seems intuitive that migratory behaviors would be passed from mother to offspring, yet observed evidence of this transmission from mother to offspring is lacking. Scientists think that mule deer fawns migrate with their mother during their first fall and spring migrations. During this time, a mother could show her offspring her migratory route and, by establishing the memory in her offspring, pass it down to the next generation. Yet, we do not know whether or not this transmission occurs. To that end, we are studying whether migratory behaviors are established by being passed from mother to daughter during the first year of life –the ontogeny of mule deer migration.


Rhiannon Jakopak
Masters Student
Wyoming Cooperative Fish and Wildlife Research Unit
University of Wyoming
Dept. 3166, 1000 E. University Ave.
Laramie, WY 82071
Email: [email protected]


Kevin Monteith
Assistant Professor
Haub School of Environment and Natural Resources
Wyoming Cooperative Fish and Wildlife Research Unit
University of Wyoming, Dept 3166
1000 E. University Ave.
Laramie, WY 82071
Email: [email protected]


Gary Fralick
Wildlife Biologist
Wyoming Game and Fish Department
P.O. Box 1022
Thayne, WY 83127
Email: [email protected]

Project Lead


Summer 2016 – Summer 2018: Mule deer fawns are collared as part of the Wyoming Range Mule Deer Project and Deer-Elk Ecology Research Project

Summer 2018 – Summer 2020: Collared fawns are continually monitored into adulthood

Fall 2020: Analyze data

Spring 2021: Finalize, write, and distribute findings

Funding & Partners

Wyoming Game and Fish Department · Bureau of Land Management · Wyoming Wildlife and Natural Resource Trust · Muley Fanatic Foundation of Wyoming · Knobloch Family Foundation · Wyoming Governor’s Big Game License Coalition · Wyoming Outfitters and Guides Association · Wyoming Animal Damage Management Board · U.S. Forest Service · U.S. Fish and Wildlife Service – Cokeville Meadows National Wildlife Refuge