No abstract

This study aimed to identify tools for taking capercaillie habitats into consideration in forest management. This would provide new alternatives for ecologically more sustainable forest management. Capercaillie summer and winter locations, from wildlife monitoring counts (1998)(1999)(2000)(2001)(2002)(2003)(2004) in northern Finland, and reference, non-capercaillie locations were combined with forest planning data, and the area proportions of different landscape classes in an 800-m radius circle surrounding capercaillie and reference locations were compared. Thinning stands (in summer and winter) and spruce mires (in summer) were more abundant in capercaillie habitats than in reference landscapes, whereas e.g. seedling stands, mature stands and waste land areas were less abundant. The relative habitat use was highest in mean tree diameter (DBH) classes from 10.5 to 14.5 cm in summer habitats of adult capercaillie in heath forests, whereas in peatland forests, in brood habitats and in winter habitats it peaked in diameter classes 14.5 to 18.5 cm. The tree layer density was positively associated with the relative habitat use. A trend of lower habitat use was detected in the largest diameters (17-40 cm) in comparison to middle-sized diameters (10-16 cm) in heath forests, but not in peatland forests. Relatively young managed forests (age 30-40 years or more) can form suitable capercaillie habitats in north-boreal forests. However, this suitability is not necessarily permanent. Understorey management, longer rotations and multicohort forest management are suitable tools for capercaillie habitat management, because they can increase the available cover close to the ground, canopy cover, overall forest cover at the landscape scale and bilberry cover.

We studied the relationship between landscape composition and capercaillie density in 50 km ¥ 50 km grids in Finland, where modern forestry started in the 1950s and most of the forests are in commercial use. Capercaillie density was positively associated with the young thinning stand proportion throughout the country, but unlike in numerous older studies, it wasn't positively associated with the mature stand proportion in any part of the country. In central Finland this relationship was even negative. In central and southern Finland capercaillie density was associated positively with the forest land proportion, and negatively with the open area proportion. Results suggest that the overall amount of the forest cover is important for the capercaillie, and that clear-cut areas in the 1950s and 1960s, known as 'large age classes', have developed as suitable for them. A new aspect based on results is the potential reduction in the mature forest quality as capercaillie habitats.

No abstract

To be presented, with the permission of the Faculty of Forest Sciences of the University of Joensuu, for public criticism in auditorium N100, Yliopistokatu 7, on 5 th June, 2009 at 12 o'clock noon.