摘要
The trend of fencing grassland as livestock paddocks is spreading on the Eurasian steppe,however,its impacts on grassland wildlife are little known.In order to explore such impacts,we carried out a field study on how grassland fencing impacts Przewalski's gazelle(Procapra przewalskii),a species listed as EN(Endangered) by SSC/IUCN,on the Qinghai-Tibet Plateau.The results revealed that(1) in the fenced areas,daily movement distance of Przewalski's gazelle was 5081±1187 m(Hudong-Ketu) and 4110±912 m(Yuanzhe),which was much shorter than the 7223±546 m recorded in an unfenced area(Kuaierma);(2) the feeding bout duration of Przewalski's gazelle was much shorter in the fenced habitat;(3) the frequency of walking along both high or low fence lines reached about 81%;while the frequency of jumping across the low fence line was only about 1.2% and frequency of crawling through the bottom of the high fence lines was about 17.8%;(4) the size of post-fencing habitat decreased to about 20% and 6% of the sizes of pre-fencing habitat in Hudong-Ketu and Yuanzhe areas respectively,but no clear change in the size of habitat area was found in the unfenced Kuaierma area;and(5) the fence lines impaired the possibility of gazelles to escape from predators and occasionally trapped the Przewalski's gazelle which failed to jump over the fence lines.Death occurrence of Przewalski's gazelle in the intensively fenced area,including gazelles strangled by fence lines and predated by wolves,reached 5% of the population size in Yuanzhe and up to 15%-20% in Hudong-Ketu.This study highlights the negative impacts of grassland fencing on Przewalski's gazelle and proposes measures for integrating conservation of this gazelle with livestock management practice.
The trend of fencing grassland as livestock paddocks is spreading on the Eurasian steppe, however, its impacts on grassland wildlife are little known. In order to explore such impacts, we carried out a field study on how grassland fencing impacts Przewalski＇s gazelle （Procapra przewalskii）, a species listed as EN （Endangered） by SSC/IUCN, on the Qinghai-Tibet Plateau. The results revealed that （1） in the fenced areas, daily movement distance of Przewalski＇s gazelle was 5081±1187 m （Hudong-Ketu） and 4110±912 m （Yuanzhe）, which was much shorter than the 7223±546 m recorded in an unfenced area （Kuaierma）; （2） the feeding bout duration of Przewalski＇s gazelle was much shorter in the fenced habitat; （3） the frequency of walking along both high or low fence lines reached about 81%; while the frequency of jumping across the low fence line was only about 1.2% and frequency of crawling through the bottom of the high fence lines was about 17.8%; （4） the size of post-fencing habitat decreased to about 20% and 6% of the sizes of pre-fencing habitat in Hudong-Ketu and Yuanzhe areas respectively, but no clear change in the size of habitat area was found in the unfenced Kuaierma area; and （5） the fence lines impaired the possibility of gazelles to escape from predators and occasionally trapped the Przewalski＇s gazelle which failed to jump over the fence lines. Death occurrence of Przewalski＇s gazelle in the intensively fenced area, including gazelles strangled by fence lines and predated by wolves, reached 5% of the population size in Yuanzhe and up to 15%-20% in Hudong-Ketu. This study highlights the negative impacts of grassland fencing on Przewalski＇s gazelle and proposes measures for integrating conservation of this gazelle with livestock management practice.
基金
supported by the National Natural Science Foundation of China (31070469 and 31070348)
the Key Program of Knowledge Innovation Program of Chinese Academy of Sciences (KSCX2-EW-Z-4)
the Science and Technology Supporting Project of MOST (2008BAC39B04)
the Whitley Foundation for Nature
