Open AccessCommunity structure of birds in agricultural areas in summer and winter in Denmark
Author(s) -
Møller Anders Pape
Publication year - 1984
Publication title -
ecography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.973
H-Index - 128
eISSN - 1600-0587
pISSN - 0906-7590
DOI - 10.1111/j.1600-0587.1984.tb01142.x
Subject(s) - habitat , abundance (ecology) , relative species abundance , ecology , species diversity , global biodiversity , vegetation (pathology) , common species , spatial distribution , species richness , biodiversity , biology , geography , medicine , remote sensing , pathology
The spatial distribution of bird species was studied by grid mapping in 273 (250 × 250 m) squares in an open rural area in Denmark in summer and in winter. Species frequencies (fraction of squares with species present) followed a logarithmic linear distribution when arranged by their rank. Species frequency probably reflects relative abundance as the two variables were highly positively correlated. The number of species increased with the number of vegetation layers, ground water level, and habitat diversity. The distributional segregation of species was similar in summer and in winter, even though the winter assemblage only comprised 62% of the species present in summer. The number of species per square in winter was positively correlated with the number of species in summer; the fraction of species wintering in various habitats increased with the number of vegetation layers and the presence of human habitation. Species that flocked had a low similarity between their summer and winter distributions. Among pairs of potential competitors the smaller species either changed distribution locally or emigrated from the area in winter. The number of habitat types was reduced from 5 in summer to 4 in winter, and the number of species assemblages decreased from 5 in summer to 3 in winter. Birds were absent from 52% of the squares in winter.