Habitat selection in Paridae and possible impacts of forestry

Parids are mostly sedentary birds and therefore habitat selection is important for both winter survival and reproduction in the breeding season. Because of their residency, parids are vulnerable to habitat fragmentation and loss of habitat. I reviewed habitat selection in parids in North-America and Europe and compared with a field study of populations of tits in an area of southeastern Norway with extensive forestry to discuss possible impact of forestry on parids. North-American and European parids show similar patterns due to habitat selection. Almost all species forms stable flocks and are, to some extent, territorial during winter. The European species often form mixed-species flocks with other tits, goldcrest (Regulus regulus) and common treecreeper (Certhia familiaris). All species that form flocks also hoard food and are dependent on good hoarding sites. The great tit (Parus major) and the blue tit (Cyanistes caerulus) differ from the other species. They do not form stable flocks, are not territorial and do not hoard during winter. Together with coal tit (Periparus ater), they are also partly migratory. Human land use, like modern forestry, is believed to have a great impact on the biodiversity. The consequences of modern forestry management have been habitat fragmentation, alteration, and loss of forest has taken place. In my field study I looked at possible differences in population size and structure of winter flocking titmice communities in order to see if forestry may have impact on the abundance of small passerines in winter. Point-transect with sound playback were used as method to collect data. The field work was done from 23th January to 17th March 2015, in Varaldskogen State Forest, Norway. Abundant species in this forest area are willow tit (Poecile montanus), crested tit (Lophophanes cristatus), goldcrest, common treecreeper and great tit. The results did not show any major differences in abundances. Surprisingly, the willow tits turned out to be more abundant in plantation forest than in natural forest. Due to the relative small number of observations and only one year of collection of data (2015), further studies should aim at having more data from a longer period of time and to use improved methods