| To discuss habitat use and habitat charateristics and the effects of group size and location in the flockings on the individual foraging behavior, the foraging behavior of wintering Black-necked cranes were observed using focal animal sampling and continuous recording during Nov.to Dec. 2007 at Dashanbao National Nature Reserve. At the same time, the foraging habitat use and feeding sites characteristics were investigated using Fixation observation area and systematic line transects.The foraging time accouted for about 80% of the dural activities in Dashanbao Nature Reserve during Nov. to Dec. 2007 years. The mean foraging duration increases as the group size, but the search intensity decline. Feeding intensity don't have linear relation to the flock sizes. The group sizes affect the mean foraging duration and the feeding intensity significantly(P<0.01), but don't affect the search intensity(P>0.05). These maybe a tradeoff results between"more eyes strategys"and more competition for food as flock sizes increase.The location in the flocks don't influent the foraging behavior, but the flocking patterns have the effect. The mean foraging duration in familial crane is shorter than that of different locations in flocks, but the feeding intensity and the search intenity are longer. The adults in families gain enough food by improveing feeding intensity and search intensity, but by increaseing mean foraging duration in the flockings. Occupying territory or flocking on the families in winter was influented by food richness.The study area was divided into five foraging habitats according the landscape and the land use status, namely, shallow-swampy meadow, farmland, weed meadow, Poa annua meadow and the mixed meadow of Dactylis glomerata and Trifolium repens, The shallow-swampy meadow and farmland are the preference foraging habitat(Pw < Pi)(P<0.01), but the other three habitat are the avoided habitat(Pw>Pi). The preference of Black-necked cranes varied in different months. During the Nov., the farmland was the prefered habitat, but mixed meadow of Dactylis glomerata and Trifolium repens and weed meadow were the avoided habitats, and the shallow-swampy meadow and the Poa annua meadow were used normally. During the Dec., farmland and shallow-swampy meadow were the prefered habitat, and the others were the avoided habitat.The RSFs empirical model was diagnosed by ROC, and then obtain the feeding sites characteristics compareing with the results of discriminant analysis. The interference distance, space of water, density of soil animal, cover of Trifolium repens, vegetational complex degree and Compositae height were the factors influenceed the feeding sites selection. Compareing with the non-feeding sites, the characteristics of feeding patchs showed that near the water(133.00±14.88) (P<0.01), less interference(287.56±14.05) (P<0.01), more richness of soil animal(117±27.6) (P<0.01), dwarfer Compositae(1.83±0.86) (P<0.01), more Trifolium repens(0.43±0.05) (P<0.01) and less vegetation species(5.8±0.4) (P<0.05).To discuss the sex difference in behaviors, the productive Black-necked cranes were investigated using focal animal sampling and continuous record at Naecuo wetland in Northern Tibet from April to June 2006. The Black-necked cranes sex difference was identified by Unison call.The foraging behavior was the main diurnal activity, and breeding behavior distributed mainly at morning(0900) and afternoon(1800) during the prelaying period. There are difference between the males and females. The diurnal time-activity budgets of males was indicated that Foraging behavior consists of major activity, accounting for 41.24% of the whole time budget, then vigilance(28.50%), maintenance (16.7%), locomotion (8.04%), other behavior(4.16%) and breeding behaviors (1.47%). That of females indicated that Foraging behavior accounts for 44.67% of the whole time budget, then maintenance (24.31%), vigilance(16.67%), locomotion (7.15%), other behavior(4.57%) and breeding behaviors (2.63%). Time budgets of vigilance and locomotion behavior of the males are more than that of females, espscially the vigilance behavior significantly(P<0.01). This was consistent with the pair-bond investment in the monogamous birds. However, the other four behaviors between the males and the females are contrary at a certain degree. These maybe suggest that the femals in the study area were health.The breeding behavior and foraging behavior were the main behaviors in the incubational period, especially the breeding behavior was the most at every hours, and distributed mainly at morning(0800) and afternoon(1700). The diurnal time-activity budgets of males was indicated that breeding behavior consists of major activity, accounting for 52.40% of the whole time budget, then Foraging behavior(29.92%), vigilance(6.54%), maintenance (4.53%), locomotion (4.25%) and others(2.37%). That of the females showed that breeding behavior consists of major activity, accounting for 60.49% of the whole time budget, then Foraging behavior(28.84%), vigilance(4.13%), maintenance (3.60%), locomotion (2.45%) and others(0.51%). There are no significantly difference between the male behavior and that of female. These suggest that the diurnal activity-time budgets of male and the female satisfy the needs on successful reproduct and the survival needs.In fact, this study offers some basic ideals for the farther study, because there are some problems don't resolve in this study due to the shorter field time, lacking financing and field experience. Baseing on the above results, the farther study will carry out in the light of the followings.(1) the costs and the benefits on the familial crane takeing part in flocking or not during winter; (2)habitat selection on Black-necked cranes and the sympatricwatefowl based on the individuals, but the role of evolutional stable strategy (ESS) in the ecology should be payed attention; (3)the real mating system, sexual selection and the reproductive seccessful rate of the breeding Black-necked cranes should also get more attention.
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