FOREST VEGETATION, EARTHWORM (LUMBRICIDAE), AND WOODCOCK (SCOLOPAX MINOR) RELATIONSHIPS (NEW YORK)

The relationships among forest types, earthworm communities, and woodcock (Scolopax minor) diurnal habitat selection were examined in Oswego County, New York from 1982 to 1984. Ninety-seven forest and shrub stands were sampled for earthworms to document earthworm habitat affinities. A total of 44,814 worms of seven species was collected from the stands sampled. The distribution and abundance of worms was closely associated with the type of overstory vegetation in the stand; soil characteristics such as moisture, temperature, pH, and others had limited or no association with worm distribution and abundance. Stands composed of mull-forming overstory vegetation (alder Alnus rugosa, apple Malus spp., arrowwood Viburnum dentatum, dogwood Cornus stolonifera, aspen Populus spp., ash Fraxinus spp., and fire cherry Prunus pensylvanica) had the highest worm densities (30 to 220 worms/m('2)) composed primarily of Lumbricus terrestris and Aporrectodea caliginosa. Stands composed of mor-forming vegetation (red maple Acer rubrum, sugar maple Acer saccharum, black cherry Prunus serotina, beech Fagus grandifolia, red oak Quercus rubra, and conifers) had low worm densities (<10 worms/m('2)) mainly composed of Dendrobaena octaedra. Woodcock habitat affinities were ascertained by comparing the habitat characteristics of flush sites with random sites and by comparing woodcock use of the 97 stands used for worm habitat analyses. Comparisons of the habitat characteristics of flush sites with random sites indicated a significant classification model which incorporated three variables--worm abundance, canopy height, and herbaceous stem density. Woodcock were also only positively associated with mull-forming vegetation and only negatively associated with mor-forming vegetation. Analyses of woodcock use and relative use of the stands used to examine worm habitat affinities indicated that woodcock presence and relative use of stands was associated with worm abundance, overstory stem density, and distance to the nearest forest edge. Analysis on both woodcock data sets indicated that woodcock diurnal habitat was characterized by high worm abundance and by the vegetation structure of late seedling to pole-sized forest growth stages. The overall relationships among forest types, earthworms, and woodcock were that overstory vegetation (mull-forming species) influenced worm abundance which in conjunction with the stand's structure influenced woodcock diurnal use of the stand.