WILDLIFE BROWSING EFFECTS ON WYOMING BIG SAGEBRUSH GROWTH AND SURVIVAL ON RECLAIMED MINED LANDS

Authors: PARTLOW, KRISTENE - UNIVERSITY OF WYOMING; Schuman, Gerald; OLSON, RICHARD - UNIVERSITY OF WYOMING

Submitted to: Seed and Soil Dynamics in Shrubland Ecosystems Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/11/2003
Publication Date: 4/18/2004
Citation: Partlow, K.A., Schuman, G.E., Olson, R.A. 2004. Wildlife browsing effects on wyoming big sagebrush growth and survival on reclaimed mined lands. Seed and Soil Dynamics in Shrubland Ecosystems Proceedings. pp. 198-205.

Interpretive Summary:

Technical Abstract: Ensuring Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young) survival remains a challenge on many mines even years after initial establishment. Wildlife utilization may be a major influence on its survival. A wildlife-proof exclosure was erected in June 2001 on a portion of a study initiated in 1990 at the North Antelope/Rochelle Complex Mine in northeastern Wyoming. Investigations focused on the influence of wildlife utilization on big sagebrush survival and growth under 3 grass seeding rates, inside and outside of the exclosure. Growth, browsing, and survival were evaluated on 72 marked sagebrush plants inside and outside of the exclosure. Permanent 1 m2 quadrats established in 1990 and 2 x 12 m belt transects were utilized to estimate big sagebrush density both inside and outside of the wildlife exclosure. Big sagebrush mortality, based on the 72 marked plants, was 24 outside the exclosure and 8 inside the exclosure for 2001-2002. Grass seeding rate had no effect on mortality inside the exclosure; however, mortality outside the exclosure was lowest in the highest grass-seeding rate, 32 kg ha-1. The higher grass-seeding rate appears to have enhanced big sagebrush survival although a specific ecological explanation is not clear from our data. Other research has shown similar responses whether browsed by livestock or wildlife. Big sagebrush browsing outside of the exclosure was 100% on the marked sagebrush plants and no browsing was evident inside the exclosure. Fecal pellet groups/individual pellets along with bite characteristics on the sagebrush leaders indicated that rabbits were the major browsers. Annual leader length (new growth on sagebrush) averaged 44.3 mm inside the exclosure and only 16.8 mm outside the exclosure for the 2 years. Wildlife use can have damaging effects on the shrub component of reclaimed lands and may prevent achieving the shrub density requirement for bond release. Therefore, wildlife management on reclaimed mine lands may be necessary where wildlife numbers are high.