Mortality of Cattle on Two Types of Grazing Areas in Northwestern Alberta

Abstract

Cattle mortality was investigated on 3 intensively managed Provincial Grazing Reserves (PGR) and 7 heavily treed, less intensively managed woodland grazing leases (Simonette pastures) in northwestern Alberta during 1976-1979 inclusive. Cattle losses (including dead and missing animals) on the Simonette pastures averaged 2.7 times greater than losses on the PGR. Calves were lost at a greater rate than yearlings and mature cattle on both types of grazing areas. Calves born on the Simonette pastures died at a rate nearly 5 times that of calves born prior to entering these pastures. Death from predation accounted for 48.4% of 33 recorded deaths on the Simonette pastures compared to 3.3% of 90 deaths on PGR. Greater losses of cattle on the Simonette pastures appeared associated with greater concentration of trees, less intensive supervision, and greater numbers and species of predators.