Winter grazing of reindeer in woodland lichen pasture Effect of lichen availability on the condition of reindeer

Winter grazing of semi-domesticated reindeer (Rangifer t. tarandus) was inv estigated at the woodland lichen pasture (lichen approximately 550 kg DM ha (-1)) in Kaamanen, northern Finland during the winter 1996-1997. Nine femal e reindeer mainly due their food in the snow for 122 days (3 Decembrr-1 Apr il) in a fenced area of 36.3 ha. Over half of the fenced area was lichen do minated dry pine forest. The amount of lichens in lichen forest inside the fence was estimated before and after grazing. Area of grazed and condition of reindeer as well as snow conditions were monitored. Reindeer grazed over the whole area of lichen forest in early winter but from mid-winter they t ended to graze on the areas with the greatest lichen abundancy. The amount of lichens measured decreased in the latter areas by 40% and in the other p art of the lichen pasture by 17%, respectively. In both of these areas the residual amounts of lichens left after grazing were similar. Of the dominan t lichens, the amount of C. stellaris decreased the must and the amount of Cl. uncialis the least. During the study, the estimated average daily area grazed varied from 4 to 87 m(2) per reindeer. It was calculated that indivi dual reindeer obtained 2.6 kg of lichen DM per day during the most intensiv e digging period when the body condition score and weight of reindeer incre ased. Otherwise, the body condition score and weight decreased. Reindeer fi nished foraging for ground lichens and started to search for arboreal liche ns in mid-March when the snow layer was 70-80 om thick and contained some h ard snow layers which lifted reindeer. Both the amount of lichens in the pa sture and the snow conditions essentially affect the nutritional status of reindeer in the woodland region during winter. Assuming that a reindeer is able to graze around 30 m(2) per day in the snow during mid and late winter , there should be, on the basis of energy demand and grazing behaviour of r eindeer as well as the nutritive value of lichen, an estimated 1000 kg lich en DM ha(-1) available in a good condition woodland lichen pasture. (C),: 2 001 Elsevier Science B.V. All rights reserved.