| Tibetan gazelle (Procapra picticaudata) belongs to Mammalia, Artiodactyla, Procapra. It is an ungulate owned only by Tibet Plateau. Now it is the second-class protected wild animal in China. Historically Tibetan gazelles widely distributed in the total Tibet Plateau and its extended area. Their population size and distribution area are dramatically declining so that they have already been in severe danger, because of the changing of climate and human influence. The conservation and management of wild population encountered great obstacle, because of the lacking on Tibetan gazelle's biological information. The key to establish the conservative program is to know their adaptive strategy under such a serious human pressure. This is benefit to the recovery of their wild population, and keeps their head above water.In August of 1996, June-August of 1999, July-October of 2003 and March-Spring of 2004, making use of binocular, GPS, DV and DC etc., we study population distribution, group characteristics, feeding behaviors and habitat status of Tibetan gazelles with sampling belt, fixing observation and sampling methods in the quantified manner. The results of these works are as below:A field survey conducted in Shiqu County shows that the density of wild Tibetan gazelles population is 0.117 individuals/km~2. Tibetan gazelles mainly distribute in the northwest and northeast of Shiqu County and are probably influenced by the nomadic live of local people, which distribution is typically alp grassland meadow belt. The main factors threatening the wild population are degradation and loss of habitat, poach and snow disaster. By analyzing the meadow proportion of 5 counties where Tibetan gazelles exist, we find that the average meadow proportion is 70%, and the average desert meadow proportion is 10%, therefore, the really distribution proportion of Tibetan gazelles is only about 60%. If so, the population number of Tibetan gazellesmay be less than one hundred thousand individuals in the total Tibet Plateau.Space distribution pattern of Tibetan gazelles shows that the level distribution is relatively even, and plumb distribution mainly is between 4 200 and 4 700 m elevation, but the aggregated characterize their distribution pattern. The most regular group form is 2 to 9 individuals/group, which may be the optimal group size. The small group form is a common adaptive means of middle-small animals so that they adopt the strategy of concealment, running and evasion while defending natural enemies. The grouping behaviors of Tibetan gazelles don't belong to temporary group, but stable and regular one. It is arise from that Tibetan gazelles adapt environment, and is in favor of population diffusion.Tibetan gazelles have 3 group types, namely male-only group, female-only group and mother-offspring group, except mating season. However, spring has not mother-offspring group, possibly because yearling individuals have already hived off to join in their respective group, or have migrated towards winter pasture with domestic animals. Group sizes of all group types are not different for Tibetan gazelles in the same season because of the same climate condition, but there are differences between seasons. Fluctuation of female-only group size causes this difference, which makes the mean group size in summer smaller. Therefore, the birth of female may be one of the reasons for the group difference of all group types for Tibetan gazelles.Feeding site of Tibetan gazelle has many rule characteristics. In summer, they are usually located in meadow slope, <20° slope degree, <500 m to water resource , farther away human harassment (for example, more than 2 000 m far away highway), and better concealment. But Tibetan gazelles are not farther away domestic animals (500 — 1 000 m), maybe because of coo-defending natural enemies, a kind of anti-predation strategy. The richest food season is in autumn, Tibetan gazelles enlarge the feeding range in slope direction (from suuny slope to Half gloomy and half sunny slope) and distance from water resource (from <5...
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