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Zhang Y.,Beijing Forestry University | Cao Q.S.,Princeton University | Cao Q.S.,Smithsonian Conservation Biology Institute | Rubenstein D.I.,Princeton University | And 7 more authors.
PLoS ONE | Year: 2015

Acquiring water is essential for all animals, but doing so is most challenging for desert-living animals. Recently Przewalski's horse has been reintroduced to the desert area in China where the last wild surviving member of the species was seen before it vanished from China in the1960s. Its reintroduction placed it within the range of a close evolutionary relative, the con-generic Khulan. Determining whether or not these two species experience competition and whether or not such competition was responsible for the extinction of Przewalski's horses in the wild over 50 years ago, requires identifying the fundamental and realized niches of both species. We remotely monitored the presence of both species at a variety of water points during the dry season in Kalamaili Nature Reserve, Xinjiang, China. Przewalski's horses drank twice per day mostly during daylight hours at low salinity water sources while Khulans drank mostly at night usually at high salinity water points or those far from human residences. Spatial and temporal differences in water use enables coexistence, but suggest that Przewalski's horses also restrict the actions of Khulan. Such differences in both the fundamental and realized niches were associated with differences in physiological tolerances for saline water and human activity as well as differences in aggression and dominance. Copyright: © 2015 Zhang et al.

Liu G.,Beijing Forestry University | Shafer A.B.A.,Uppsala University | Zimmermann W.,Cologne Zoological Garden | Hu D.,Beijing Forestry University | And 4 more authors.
Biological Conservation | Year: 2014

Przewalski's horse went extinct in the wild in the mid 1960s. Starting in 1985, individuals were brought from western zoos to two centers in China and breeding programs were initiated. With the increasing size of captive populations, two reintroduction projects were launched in the northwestern China in 2001 and 2010. Knowledge on genetic diversity in China's horse populations is limited, but would help improve the genetic management and assess the success of the reintroduction. Accordingly, one reintroduced and two captive populations were examined with 10 microsatellite loci together with pedigree data. The results showed higher level of diversity within the captive populations than the reintroduced population, indicating some alleles may have been lost during reintroduction. Genetic differentiation was detected among populations (FST=0.09±0.05, RhoST=0.05±0.02) and Bayesian clustering supported the presence of three subpopulations. The highest genetic differentiation was observed between the captive and reintroduced populations, and inbreeding coefficients were generally higher in the reintroduced population. Temporal estimates of both pedigree and microsatellite data showed a high, but decreasing level inbreeding. Through simulations, we estimated that the reintroduced population needs more than 100 individuals to retain approximately 90% of its current, already depauperate, genetic diversity. We have provided recommendations for the management program concerning introgressed genes from domestic horse and the number and origin of individuals for future reintroductions. © 2014 Elsevier Ltd.

Xia C.,Xinjiang Institute of Ecology and Geography | Cao J.,Wild Horse Breeding Center | Zhang H.,Wild Horse Breeding Center | Gao X.,Xinjiang Institute of Ecology and Geography | And 2 more authors.
Biological Conservation | Year: 2014

Przewalski's horse reintroductions to Xinjiang, China were initiated in 1985. Here, we present the first data on population development and current problems of the Przewalski's horse in both captive and released populations in Xinjiang. From 1985 to 2005, a total of 24 captive Przewalski's horses (14 males and 10 females) were brought from western zoos to the Jimsar Wild Horse Breeding Center (WHBC) in Xinjiang. In 1988, the first foal was born. Since then, a total of 285 foals have been born and the number of animals in the captive population continues to increase. In August 2001, the first group of horses was released into semi-wild conditions in the Kalamaili Nature Reserve (KNR). Released horses were allowed to range freely from spring to fall, but were driven into a winter coral to allow for supplemental feeding and to increase winter survival, and to reduce competition with domestic horses from local herdsmen who use the KNR as winter pasture. By December 2013, a total of 89 horses (32 males and 57 females) in 14 groups had been transferred to semi-release; and within two years after the first release, the first foal was successfully born in the wild. By 2013, the reintroduced animals had formed into 16 groups (127 individuals, 13 breeding and 3 bachelor group) in 5 sites. To date, this is the most comprehensive and successful Przewalski's reintroduction effort in China. © 2014 Elsevier Ltd.

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