Spatial variations, patterns and management options in upland bird communities.

Abstract

1. Two ecological approaches are explored in relation to management options for upland birds.

2. The first identifies correlates of distribution and abundance. There are no clear regional trends in bird species richness or associations with soil fertility. Species abundance is loosely associated with fertility, habitat structure and arthropod-rich patches.

3. Small areas of rough pasture and the construction of bog flushes may help to increase arthropod abundance and densities of upland birds. However, these could alter other factors and influence community stability.

4. The second approach proposes the application of empirical models. A host-parasite model is applied to the management of red grouse (Lagopus lagopus scoticus) to reduce the impact of the nematode parasite, Trichostrongylus tenuis.

5. Reducing either the life expectancy of free-living stages through environmental management or the size of the adult worm population through chemotherapy appears untenable. Indirect chemotherapy and an improvement in the hen's plane of nutrition through reduced competition with other herbivores are suggested as possible control methods.

6. Although both approaches have their disadvantages, they should be considered complementary and not mutually exclusive.