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The incidence function model is derived from a linear first‐order Markov chain of the presence or absence of a species in a habitat patch. The model can be parameterized with “snapshot” presence/absence data from a patch network. Using the estimated parameter values the Markov chain can be iterated in the same or in some other patch network to generate quantitative predictions about transient metapopulation dynamics and the stochastic steady state. We tested the ability of the incidence function model to predict patch occupancy using extensive data on an endangered butterfly, the Glanville fritillary (Melitaea cinxia) Parameter values were estimated with data collected from a 50‐patch network in 1991. In 1993 we surveyed the entire geographic range of the species in Finland, within an area of 50 × 70 km2, with 1502 habitat patches (dry meadows) of which 536 were occupied. Model predictions were generated for the 1502 patches and were compared with the observed pattern of occupancy in 1993. The model predicted patch occupancy well in more than half of the study area, but prediction was poor for one quarter of the area, probably because of regional variation in habitat quality and because metapopulations may have been perturbed away from the steady state. The incidence function model provides a practical tool for making quantitative predictions about metapopulation dynamics of species living in fragmented landscapes.

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The capercaillie Tetrao urogallus is widely accepted as a species seriously suf fering from fragmentation of forests and habitat loss. Foresters as well as conservationists agree on the need and principles for maintaining viable pop ulations, but the proposed management means often differ. The approach cur rently favoured by Finnish foresters is to manage capercaillie leks and their sur roundings using methods that differ from those used in intensive forestry. It may be desirable to prove that forests with capercaillie leks also favour other for est bird species and biodiversity in general. During the last 16 years (1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002), forest birds have been censused and capercaillie leks were mapped in the 465-km2 study area in southern Finland. Most of the study area consists of sprucedominated mature forests. The remainder of the landscape is a mixture of var iously aged forests, agricultural areas, lakes and scattered human settlements with a gradient from an agricultural-forest mosaic to forest-dominated areas. The old-growth forest bird species three-toed woodpecker Picoides tridactylus, pygmy owl Glaucidium passerinum and red-breasted flycatcher Ficedula parva were more abundant within 300 m and 1,000 m radii around capercail lie lek sites than in non-lek control sites. Also the overall species richness of breeding forest birds was higher in the vicinity of capercaillie leks. On a larg er scale (100 x 100 km squares), using the wildlife triangle scheme developed in Finland, we show that the density of capercaillie closely coincides with a wildlife richness index describing the total abundance of 15 other forestdwelling mammal and bird species with diverse ecology and habitat require ments. Capercaillie is a flagship species for foresters, and can be considered a good candidate for an umbrella species for wildlife in taiga forests.