Sheep Threaten Biodiversity

Sheep Threaten Biodiversity

April 28, 2004

The sheep in Finnmark are gourmets. The menu is topped by juicy herbs and grass in the rich Dark-leaved Willow woods (

Salix myrsinifolia ssp. borealis). Too high grazing pressure results in anthropogenic grassland with monotonous vegetation dominated by Tufted Hair-grass (

Deschampsia cespitosa).

Norut IT has conducted the study “Effects on vegetation from wood cutting and grazing in Nesseby kommune”. The study was commissioned by the agriculture authority in Finnmark.

Dark-leaved Willow disappears

Woodlands in Finnmark are used actively for sheep grazing and wood cutting. Each year more than 20.000 m3 of birch timber is cut down. The objective of the project was to gain increased knowledge about effects from intense grazing in birch forests and to study wood cutting methods which will enhance growth of new forest in grazing areas. Test areas have been fenced in and the development of vegetation and trees has been analysed during several years.

Unfortunate

2000 sheep are grazing in the 150 square kilometer study area. The grazing pressure leads to great changes in the vegetation. From an ecological point of view there is an over-grazing in the biologically diverse Dark-leaved Willow woods along the streams and rivers, and it is fair to say that this particular forest type is threatened. Sheep graze in the brush and field layer, in addition moose will graze the willow tops during winter. In certain areas the wood type was virtually extinct, the willows are dead and the field layer has spots of monoculture Tufted Hair-grass. This transition towards anthropogenic grassland does not harm the grazing conditions for sheep (they readily accept the change from gourmet to plain food), but it is unfortunate for the biological diversity in the area.

Contact: PhD stipendiat Stein Rune Karlsen, Norut IT, tlf. 7762 9441/9098 5066