AN EXPANDABLE RADIOCOLLAR FOR ELK CALVES

Expandable radiocollars, designed to monitor juvenile survival and mov ements, were placed on 132 neonatal elk (Cervus elaphus) in Yellowston e National Park during 1987-1990. A modified design of the same collar was placed on 164 neonates of the Jackson elk herd in northwest Wyomi ng during 1990-1992. One of the Yellowstone calves and 19 of the Jacks on calves cast their collars before 15 July of their birth year. Gener al deterioration of collar materials resulted in loss of the Yellowsto ne collars 12-18 months post-deployment, Separation of breakaway tabs resulted in loss of 13 collars from Jackson elk 504 +/- 60 days post-d eployment, but the remaining collars remained on elk for less than or equal to 4 years. These light-weight and adaptable collar designs achi eved study objectives. We provide design recommendations for future mo nitoring of juvenile elk.