The ultra-long-distance migrating mule deer known as Deer 255 has died. Researchers tracked her across 3,300 miles since 2016. Here, she is shown with her twin fawns in a fall 2020 migration stopover ...

Mule deer 959 was born on the western flank of the Red Desert to a mother that never leaves home. In his first year of life, the male fawn did the same, sticking tight to sagebrush-dominated natal ...