Pastures, calf production and carcass weights of reindeer calves in the Oraniemi co-operative, Finnish Lapland

Abstract

The effects of climatic and density-dependent factors on calf production and carcass weights of reindeer calves were studied between the years 1965-87 in the Oraniemi co-operative, Finnish Lapland (67°50´N). The Oraniemi area is divided into five pasture regions, in which the annual home range of the reindeer varied from 300 to 600 km2. The more than trebled reindeer density over the period 1965-87 in Oraniemi had no detrimental effect on calf production (range 15-74 calves/100 females), nor on the mean carcass weight of the calves in 1974-87 (range 16.8-23.2 kg). The annual variations in calf% were explained best by snow conditions during the previous winter and spring and their effects on the nutritional status of the females. The carcass weights of the calves were greater following a warm, rainy May and lower following a warm, rainy June and July. The weather in spring affects the emergence of green vegetation, which is reflected in the condition of females and their milk production, while the weather in early and mid-supper probably affects the quantities of blood-sucking insects and their activity. Carcass weights upon slaughtering rose from September to the beginning of December but then fell quickly. The differences in reindeer densities between the five pasture regions was not reflected in the calf% over the period 1984-87, but the carcass weights of calves were lower following high densities in the pasture regions, especially in the winter pastures.