Jeneverbessen Juniperus communis als nestplaats van vogels

In western Drenthe, junipers only occur as solitary trees amid extensive Scots pine Pinus sylvestris woodland with a sparse undergrowth of Quercus robur, Betula sp. and Rhamnus frangula. For shrub-nesting birds, solitary junipers often constitute the only nesting potential in the above-described habitat, hence the relatively high frequency of nests in junipers. This study showed that similar-structured dense Norway spruce Picea abies, Pseudotsuga menziesii, Pinus sylvestris, Ilex aquifolium and Taxus sp. were' equally preferred as nesting site if other options were absent (Table 1). Junipers and other evergreens were used as a nesting site by the same species of shrub-nesting birds, but junipers also held nests of cavity-nesters like tits (Table 1); the latter were facilitated by twisted stems in junipers, not available in spruce. Availability and structure of nesting sites are more important than tree species per se. Both in juniper as in other evergreens, nesting success was poor, i.e. 4 out of 15 nests successful in juniper, and 4 out of 13 in other evergreens.