UW-Led Study Shows Multiple Factors Shape Timing of Birth in Mule Deer

by the University of Wyoming

A five-year study of mule deer does and newborn fawns in western Wyoming shows that migrating deer have a lot to balance when it comes to birth timing.

The study led by University of Wyoming scientists challenges the long-held assumption that animals match offspring birth with the peak green-up of forage at the birth site. Instead, only deer that migrated long distances and followed the flush of spring green-up from low elevation winter ranges to higher-elevation summer ranges were able to match birth with peak green-up. Other deer migrated shorter distances and gave birth earlier, but birth was out of sync with green-up.

The researchers’ work appears in the journal Ecology.

To examine the factors shaping birth timing, researchers integrated highly detailed data on female deer, including movement data from GPS collars, body condition and gestational development from ultrasonography of adult female deer, and intensive fieldwork to locate newborn fawns.

Read more here: http://www.uwyo.edu/uw/news/2021/04/uw-led-study-shows-multiple-factors-shape-timing-of-birth-in-mule-deer.html

Read the Ecology paper: https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/ecy.3334