【作者】 邝粉良；

【导师】 刘宁；

【作者基本信息】 西南林学院 ， 野生动植物保护与利用， 2008， 硕士

【摘要】 为了探讨集群规模和群体中的空间位置对黑颈鹤个体觅食行为的影响,以及大山包黑颈鹤越冬初期的生境利用情况和取食地特征。2007年11月——2008年1月,采用焦点动物取样法观测了大山包越冬黑颈鹤的觅食行为,并利用系统样线法对黑颈鹤觅食地利用和取食地特征进行了调查。大山包黑颈鹤越冬初期的觅食行为约占昼间行为活动的80%。随着集群规模的增大,大山包黑颈鹤越冬初期的平均觅食时间增长,搜寻速度表现为下降趋势。取食强度与集群规模没有线性关系,11-20只群体的取食强度最大,可以控制该觅食群体的数量以减缓由于过度取食而导致的草地退化速度。黑颈鹤越冬初期,集群规模对平均觅食时间(kruskal-walliss test: x2 21.132, df = 3, p=0.000 )和取食强度(feeding intensity)有影响(k-s test: x2 =12.436, df = 3, p=0.006),而对搜寻速度没有影响(k-s test: x2 =2.637, df = 3, p >0.05)。这可能是由于随着集群规模的增大,增高群体的警戒水平(多眼策略),降低了个体的警戒率,使集群觅食个体的觅食时间增加。而鸟类的觅食群体超过一定规模时,鸟类的食物争夺、取食警戒和打斗等行为增加,取食强度下降。空间位置对越冬初期集群黑颈鹤的觅食行为没有影响,而集群形式对觅食行为的差异有一定程度的影响。家庭鹤的平均觅食时间比群体中不同空间位置个体的短,但取食强度和搜寻速度较高。家庭鹤利用加快搜寻速度和提高取食强度获得足够的食物,而群体鹤则试图通过增加觅食时间来获得足够的食物。黑颈鹤越冬期占据领域觅食还是参与集群觅食受食物资源的丰富度影响。越冬初期,黑颈鹤偏好利用农地和浅水沼泽化草甸2种觅食地(Pw < Pi)(P<0.01),鸭茅三叶草草甸,杂草草甸和早熟禾草甸3种觅食地则显示不喜好利用(Pw>Pi)。在不同的月份中,黑颈鹤对生境的利用偏好不同。11月,黑颈鹤仅喜好利用农地,不喜好利用鸭茅三叶草草甸和杂草草甸2种觅食地,而早熟禾草甸和浅水沼泽化草甸为正常利用的觅食地。12月份,正常利用的早熟禾草甸和浅水沼泽化草甸分别成为了不喜好利用和喜好利用觅食地,其他3种觅食地的偏好没有变化。基于logistic regression分析建立的资源选择函数经验模型通过ROC曲线的检验后,与判别分析的结果相比获得大山包黑颈鹤越冬初期在草地中的取食地主要特征和影响取食斑块选择的因素。干扰距离、水源距离、土壤动物密度、白三叶的盖度、植被的复杂程度和菊科植物的高度影响着大山包黑颈鹤越冬初期在草地斑块中的取食地选择(P<0.01)。与非取食斑块相比,取食斑块的主要特征表现为距水源较近(133.00±14.88)(P<0.01),干扰较小(287.56±14.05)(P<0.01),土壤动物密度较丰富(117.03±27.55),菊科植物较矮(1.83±0.86)(P<0.01),以白三叶为优势(0.43±0.05)(P<0.01),植被种数较少(5.8±0.4)(P<0.05)。为了探讨黑颈鹤繁殖期的雌雄行为差异,2006年4-6月,采用焦点动物取样法和连续记录法对藏北那色错湿地产卵前后黑颈鹤的行为进行了观测,并根据齐鸣行为识别雌雄个体。产卵前期,取食行为是主要活动,繁殖行为主要发生在上午(900)和傍晚(1800)。雄鹤昼间行为活动的时间分配模式是取食41.24%,警戒28.5%,保养16.7%,运动8.04%,杂项4.16%,繁殖1.47%;而雌鹤的是取食44.67%,保养24.31%,警戒16.67%,运动7.15%,杂项4.57%,繁殖2.63%。产卵前,在雌雄鹤的各种行为活动中,仅有警戒行为具有极显著性统计学差异(P<0.01)。雄性在保证生存的前提下,为保证资源的安全而提高警戒,雌鹤则为了获得成功繁殖的能量而增强取食。研究结果支持单配制鸟类的配对债务投资(pair-bond investment)假说。孵化期,繁殖行为和取食行为是主要行为,繁殖行为在各时间段的百分比都是最大,但主要集中在早晨(0800)和下午(1700)。雄鹤昼间行为活动的时间分配模式是繁殖52.40%取食29.92%,警戒6.54%,保养4.53%,运动4.25%,杂项2.37%;而雌鹤的是繁殖60.49%,取食28.84%,保养3.60%,警戒4.13%,运动2.45%,杂项0.51%。雌雄鹤之间的各种行为活动都没统计学差异(P>0.05)。孵化期的时间分配以满足成功繁殖和维护本身需求为主。基于以上研究结果,为将来从以下三个方面进行深入探索奠定了基础:(1)越冬期家庭鹤的利益和代价;(3)基于个体水平研究黑颈鹤以及同域分布的其它鸟类的生境选择;(2)黑颈鹤的婚配制度、性选择、繁殖成功率等生态生物学内容。更多还原

【Abstract】 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.更多还原