Foraging Behavior And Habitat Preference Of Black Woodpeckers Dryocopus Martius In Broad-leaved Korean Pine Forests

The Black Woodpecker(Dryocopus martius)belongs to the genus Dryocopus in the family Flickeridae and is a Grade II protected species,widely distributed in the Palearctic.As primary primary cavity diggers,their nests provide a key resource for secondary cavity dwellers and are considered to be indicator species for the forest.The black woodpeckers play a very important role in forest pest control by foraging on insects and their larvae and indirectly controlling forest insect pests.There are few studies on the foraging characteristics of the black woodpecker in China.This study investigated the foraging behaviour and habitat preferences of black woodpeckers in broad-leaved red pine forests in the Liangshui National Nature Reserve to provide a theoretical basis for the conservation of black woodpecker populations and forest biodiversity.This thesis uses the sample line method,sample method,fixed point observation method and focal sampling method to conduct field studies on the black Woodpeckers in spring,autumn and winter from 2020 to 2022.A sample of 153 foraging habitats(n = 79 for females and n = 74 for males)and 144 control samples were obtained.The analysis was carried out using kernel density estimation,Bailey’s method based on ’use-availability’,principal component analysis and binary logistic regression modelling to derive rhythms and characteristics of black woodpecker foraging behaviour and the main habitat factors affecting black woodpecker foraging.The results were as follows:1.There was no significant difference between male and female Black Woodpeckers in the length of single foraging sessions(P = 0.783)and there was a significant difference between Black Woodpeckers in the length of single foraging sessions between seasons(P =0.027),with longer foraging sessions in winter than in spring than in summer.The daily foraging activity rhythms of male and female Black Woodpeckers were bimodal,with maximum daily foraging activity at 08:00 and 15:00 and a midday break,and bimodal foraging activity rhythms in spring,autumn and winter,with a midday break.2.There are no discernible variations between the foraging habits of the sexes in black woodpeckers(P = 0.924),and there are four basic foraging methods: searching,chiselling,skinning,and picking.3.At the microhabitat scale,black woodpeckers preferred to foraging on fir and semi-dead standing trees(P < 0.05),more often on the main trunk(86.93%),middle and upper parts of trees(43.14%)and upper parts(32.03%)of trees.There were significant differences in the diameter at breast height and height of foraging trees(P < 0.05),a preference for foraging on thick,tall trees,and an equal preference between male and female Black Woodpeckers for species of foraging tree,condition of foraging tree and location of foraging(P > 0.05).4.At the territorial foraging scale scale,black woodpeckers preferred to foraging in natural forests with forest windows,and the dominant tree species in the patches was mostly fir.Preference was given to habitats with crown density,lower mean height of dominant trees,larger mean diameter at breast height of dominant trees,fewer live trees,dead trees,more logs in patches and the habitats where human disturbance was closer were foraged(P < 0.05).Male and female black woodpeckers had the same preference for mean height of dominant trees,mean diameter at breast height of dominant trees,number of live trees,number of dead trees and number of fallen trees.5.The key factor affecting black woodpecker foraging habitat preference was foraging tree species,with the secondary key factors being the number of dead standing trees,average height of dominant trees,height of foraging trees and number of fallen trees.It is advised that the reserve plan the density of dead and fallen trees sensibly,safeguard mature and tall stands,manage the forest sensibly,and routinely check on the black woodpecker’s ideal environment.