Utilization of Food, Water and Space by Released Przewalski Horse (Equus Przewalski) with Reference to Survival Strategies Analysis
|School||Beijing Forestry University|
|Course||Wildlife conservation and utilization|
|Keywords||Przewalski’s Horse behavior time budget diet habit analysis habitat selection fertility Rate territory population changes husbandry activities|
From July 2003 to November 2007, the study was carried out at different intervals, using all-occurrence sampling, focal sampling, sample plot investigation, and microhistological fecal analysis, to investigate the ethogram, behavior time budget, diet analysis, water resources in summer, habitat selection, expansion of living space, reproduction, chances of population and human activities effects of the released Przewalski’s Horse in in the Karamori Mountain Nature Reserve, Xinjiang. Researches were also conducted to study the ethogram, time allocation of major behaviors, seasonal traits of reproduction of both the captive and released Przewalski’s Horse. The main results are showed as follows:(1)Eighty-seven behaviors in seventeen types were observed in the study. There are five behaviors were different between the captive and released Przewalski’s Horse.(2)In the major behaviors time allocation of adult Przewalski’s Horse, feeding behavior (47.30±11.25)% occupied the most time in the spring, summer and autumn, then the second was standing resting behavior (29.07±6.29)%, moving behavior with a (14.07±3.05)%, was in the third, and was followed by recumbency behavior(3.46±1.90)%, standing behavior (3.26±1.29)% and others behaviors (2.83±1.51)%. The time used for feeding, standing resting and recumbency were significantly varied in different seasons (P<0.05). The feeding and standing behaviors of the Przewalski’s Horse were also varied under different living conditions (P<0.05), the summer diurnal activity rhythm was also different.(3) Results from diet analysis showed that nine plant species were the food resources of Przewalski horse, which mainly included Stipa gobica, Ceratoides lateens, Ceratocarpus arenaria, Anabasis brevifolia, Artemisia spp. and Salsola collina, and the former six spieces were the main food resource plant. The bachelor group has relative wider food plant spectrum compared to the family group.(4)There were two kinds of water resources available for the horse in the nature reserve, one was the surface water and the other was the springs formed by shallow underground water. From 2003 to 2005, 18 surface water resources and 2 spring water resources were investigated in the study. Surface water was found to be the first choice of the P. horse, since its quality was better than the spring water, but there were also great changes in its available volume and time. With the advantage of relatively constant volume available, the spring water also played a crucial role to the survival of the horse.(5)In different seasons, the vegetation available for the Przewalski’s Horse (P<0.01), richness of food resources (P<0.01), slope (P<0.01) and surface medium (P<0.01) were also significantly altered. But the distance to highway (P>0.05) and distance to water resource (P>0.05) did not show much differences. The Przewalski’s Horse tended to choose the places with stipa grandis community, rich food resources and the slope under 15°as their living habitats.(6)After being released, the territory of the Przewalski’s Horse had been greatly extended, from the 120km2 in 2004 to the 660km2 in 2007. With the extension of the territory, the richness of resources available to the horse also increased a lot.(7)From 2002 to 2006, twenty-four descendants were naturally bred. The average fertility rate was 38.72%, and the average survival rate was 69.05%. The unfertilized female horses resulted by excessively shifted of the stallions were the main causes to the low fertility rate. The morality rate of the infant horses was 25% in average, and 83.3% of them were infanticided by the stallions. The fertilization and breeding of the reintroduced Przewalski’s Horses were clearly characterized by seasons attribute. From May to June, 70.8% infant horses were bred. The fertility rate was 37.5% in April and 8.3% in May, and is below the rate of captive breeding 44.3% and 18.3% in the two months. In June, fertility rate was 33.3% and higher than the 18.3% of captive breeding. From above findings, it showed that the breeding peak of the reintroduced Przewalski’s Horses was later than the captive breeding ones. It suggested that the changed survival conditions and food supplies were the mains reasons attributed to the delayed breeding peak.(8)The absolute population changes and relative population changes of the horses gradually declined after the initial release. Obvious seasonal patterns could be seen in the population changes. There are eight population changes occurred in July, and was the highest number in a single month.(9)The Karamori Mountain Nature Reserve is surrounded by the winter husbandry of the minority Kazakstan people. And the husbandry activities have great interrupting effects to Przewalski’s Horse. In winter, the domestic animals poured into the nature reserve, and made local food become less available to Przewalski’s Horse. With the increasing conflicts and counteracts, Przewalski’s Horse was facing a great threaten to their survival and originality of ancestry.(10)The enlargement of the 216 national highway, exploration and development of local mines also threatened the survival of Przewalski’s Horse. For example, five horses were killed by the passing vehicles in August to October in 2007, including two adult female and three foals.