title: Individual-area relationship best explains goose species density in wetlands.
abstract: Explaining and predicting animal distributions is one of the fundamental objectives in ecology and conservation biology. Animal habitat selection can be regulated by top-down and bottom-up processes, and is mediated by species interactions. Species varying in body size respond differently to top-down and bottom-up determinants, and hence understanding these allometric responses to those determinants is important for conservation. In this study, using two differently sized goose species wintering in the Yangtze floodplain, we tested the predictions derived from three different hypotheses (individual-area relationship, food resource and disturbance hypothesis) to explain the spatial and temporal variation in densities of two goose species. Using Generalized Linear Mixed Models with a Markov Chain Monte Carlo technique, we demonstrated that goose density was positive correlated with patch area size, suggesting that the individual area-relationship best predicts differences in goose densities. Moreover, the other predictions, related to food availability and disturbance, were not significant. Buffalo grazing probably facilitated greater white-fronted geese, as the number of buffalos was positively correlated to the density of this species. We concluded that patch area size is the most important factor determining the density of goose species in our study area. Patch area size is directly determined by water levels in the Yangtze floodplain, and hence modifying the hydrological regimes can enlarge the capacity of these wetlands for migratory birds.
authors.affiliation: Resource Ecology Group, Wageningen University, Wageningen, The Netherlands; School of Life Science, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Life Science, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Jia
authors.affiliation: Resource Ecology Group, Wageningen University, Wageningen, The Netherlands.
authors.forename: Herbert H T
authors.initials: HH
authors.lastname: Prins
authors.affiliation: State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Science, Chinese Academic of Sciences, Beijing, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cao
authors.affiliation: Resource Ecology Group, Wageningen University, Wageningen, The Netherlands.
authors.forename: Willem Fred
authors.initials: WF
authors.lastname: de Boer
mesh_terms: D000818:Animals; D002681:China; D017753:Ecosystem; D005777:Geese; D011156:Population Density; D011157:Population Dynamics; D053833:Wetlands