Nest site characteristics of the Great-spotted Woodpecker in a bottomland riparian forest in the presence of invasive tree species

Abstract

This study was carried out in Hungary, in an old unmanaged riparian poplar-willow forest during the breeding seasons of 2014 and 2015. The occurrence of two invasive tree species, the green ash and boxelder, is significant in the study area, which influences negatively the populations of native riparian tree species in Central Europe. We studied Great-spotted Woodpecker nest sites in the presence of these invasive species. Throughout the study period, eight and twelve nesting cavity trees were mapped. Trees were recorded in 20-20 circular plots of 0.05 ha both for each mapped nest trees and random plots as well. Species, diameter at breast height and condition were recorded for each tree. Composition and diversity of nest site and random plots were compared. Distributions and preferences were calculated for nest tree use. Most of the recorded trees were invasive. Nest site plots had more native trees compared to random plots. Nest site showed higher diversity in terms of all three variables. Decayed and dead willow and white poplar hybrid trees were preferred for nesting. Diameter at breast height of nest trees was between 30-90 cm. Studies about cavity excavators in transformed habitats have high importance for nature conservation of riparian forests.

Foraging decisions with conservation consequences: Interaction between beavers and invasive tree species

“…This finding supports the enemy release hypothesis (Keane & Crawley, 2002). The reduction in the quantity of softwoods in the canopy layer, meanwhile, can exert a significant effect on the whole floodplain forest community (Ónodi & Winkler, 2016).…”

Woodpecker foraging activity in oak-dominated hill forests in Hungary

“…In the framework of this baseline survey, we studied foraging on living trees, a subject which is generally uncommon in woodpecker-related research. Nonetheless, some previous studies have indicated that Great Spotted Woodpeckers are often associated with living trees (Török 1990, Farris & Zack 2005, Pasinelli 2007, Ónodi & Csörgő 2014, Ónodi & Winkler 2016, Kosiński et al 2017.…”

“…The most abundant European species, the Great Spotted Woodpecker (Dendrocopos major), is often categorized as a keystone species, especially in suboptimal habitats, where there is invariably a lack of natural cavities (Pasinelli 2007). However, this species is a major nest predator of cavity-nesting songbirds and therefore, its keystone role is sometimes considered as controversial (Wesolowski 2007, Ónodi & Winkler 2016.…”

Tree Use, Niche Breadth and Overlap for Excavation by Woodpeckers in Subtropical Piedmont Forests of Northwestern Argentina

“…Moreover, the niche overlap analysis showed that Picumnus cirratus and medium-sized woodpeckers have similar use of tree species, but differ from the tree species used by Campephilus leucopogon. Therefore, be tween the smaller and medium-sized excavators, there may be competition for the use of available tree species (Kosinski & Winiecki 2004, Pasinelli 2007, Ónodi & Winkler 2016. The intermediate values from Levin's analyses suggest that woodpeckers do not use a single tree species, but instead specialize in use of several tree species (Krebs 1998).…”