Abundance and habitat preferences of the southernmost population of mink: implications for managing a recent island invasion |
| |
Authors: | Elke Schüttler José Tomás Ibarra Bernd Gruber Ricardo Rozzi Kurt Jax |
| |
Institution: | 1.Department of Conservation Biology,UFZ-Helmholtz Centre for Environmental Research,Leipzig,Germany;2.Omora Ethnobotanical Park (IEB-Institute of Ecology and Biodiversity Universidad de Magallanes, and Omora Foundation),Puerto Williams, Antarctic Province,Chile;3.Lehrstuhl für Landschafts?kologie,Technische Universit?t München-Weihenstephan,Freising,Germany;4.Fauna Australis Wildlife Laboratory, Natural Resources Program, School of Agriculture and Forestry Sciences,Pontifica Universidad Católica de Chile,Santiago,Chile;5.Department of Computational Landscape Ecology,UFZ-Helmholtz Centre for Environmental Research,Leipzig,Germany;6.Department of Philosophy,University of North Texas,Denton,USA |
| |
Abstract: | Since 2001 invasive American mink has been known to populate Navarino Island, an island located in the pristine wilderness
of the Cape Horn Biosphere Reserve, Chile, lacking native carnivorous mammals. As requested by scientists and managers, our
study aims at understanding the population ecology of mink in order to respond to conservation concerns. We studied the abundance
of mink in different semi-aquatic habitats using live trapping (n = 1,320 trap nights) and sign surveys (n = 68 sites). With generalized linear models we evaluated mink abundance in relation to small-scale habitat features including
habitats engineered by invasive beavers (Castor canadensis). Mink have colonized the entire island and signs were found in 79% of the surveys in all types of semi-aquatic habitats.
Yet, relative population abundance (0.75 mink/km of coastline) was still below densities measured in other invaded or native
areas. The habitat model accuracies indicated that mink were generally less specific in habitat use, probably due to the missing
limitations normally imposed by predators or competitors. The selected models predicted that mink prefer to use shrubland
instead of open habitat, coastal areas with heterogeneous shores instead of flat beaches, and interestingly, that mink avoid
habitats strongly modified by beavers. Our results indicate need for immediate mink control on Navarino Island. For this future
management we suggest that rocky coastal shores should be considered as priority sites deserving special conservation efforts.
Further research is needed with respect to the immigration of mink from adjacent islands and to examine facilitating or hampering
relationships between the different invasive species present, especially if integrative management is sought. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|