【作者】 刘鹏；

【导师】 贾竞波；

【作者基本信息】 东北林业大学 ， 野生动植物保护与利用， 2008， 博士

【摘要】 2005～2006年,运用野外调查、统计分析、银染和免疫组织化学、计算机模型模拟等技术手段,从种群生态和保护生物学的角度对蛇岛蝮(Gloydius shedaoensis)的种群动态、生境选择、与可食性鸟类的关系、种群生存力、物种的保护与管理等方面进行了较详细的研究。主要结果如下:1.蛇岛蝮种群的现有个体数量和分布蛇岛蝮现有种群个体数量为20281±590条,其中以蛇岛上的6沟和2沟等地数量最多。它们主要生活在灌丛和草甸中,但林缘、水池旁、道路边、岩石边等处也分布较多,只有密林及葛藤较多的地方密度较小。不同年龄组的蛇岛蝮分布范围不同,幼体和亚成体主要分布在灌丛和草甸中,成体主要分布在树林中,老成体主要分布在裸地上。影响蛇岛蝮数量和分布的主要因子有食物、植被类型、水源和岩石等。2.种群现有的基本参数蛇岛蝮种群现有的雌雄比为1.11:1.00,有效种群数量为15074条,年龄结构为幼体9.66%,亚成体15.81%,成体61.08%,老成体13.45%。种群的自然增率为0.0204,周限增长率为1.0206。种群现为稳定型,增长缓慢,估计环境容纳量值为22750条。3.种群动态变化蛇岛蝮数量和分布的具有一定的季节变化和年变化,但种群波动较小,分布范围比较固定。种群结构具有一定的变化,幼体和亚成体所占比例逐渐减少,老成体比例有所增加,说明种群增长速度正在逐渐减缓,接近环境容纳量水平。4.生境选择为了获得更多的捕食鸟类机会,蛇岛蝮多选择栖息在阳坡和半阴半阳坡的树林和灌丛中,一般处于上坡位且海拔较高的斜坡,植被盖度适中,距林缘、道路和山脊较近,同时还选择温度较高、湿度和光照强度适中的生境,以获得足够的能量。蛇岛蝮生境选择中最主要的环境因子为距林缘、道路、山脊的距离以及植被类型等,其生境选择主要受食物和热量可得性的影响。5.与可食性鸟类之间的关系在本次调查中,蛇岛蝮的可食性鸟类有9目29科99种,其中以雀形目小型鸟类为主(体长为10.00～20.00 cm),以沟底离水源较近的草甸、裸地和灌丛中可食性鸟类的种群密度较大,可食性鸟类的体长大小、数量、分布、到岛及在岛停留的时间等,都对蛇岛蝮的生境选择和捕食率有一定影响,并由此得出蛇岛蝮和可食性鸟类的种群动态变化呈显著正相关。6.蛇岛蝮消化道内分泌细胞与其消化功能的适应蛇岛蝮消化道嗜银细胞和5-羟色胺免疫活性内分泌细胞在消化道的各个部分均有分布,其形态类型多样,分布密度曲线呈波浪型,胃贲门、十二指肠和直肠部位分布密度较高,证明与其独特的食性和生活环境相适应。7.人工饲喂及能量代谢蛇岛蝮可以较长时间忍受饥饿,静止代谢率较低,能量代谢比较缓慢,进食7 d后为排泄高峰,这与其食物获得的季节性有关。成体的食物消化率较高,而幼体和亚成体较低,但具有更高的吸收能力。人工填喂流食可以满足蛇岛蝮个体的生长需要并有较高的成活率。8.种群生存力分析将估计和预测的蛇岛蝮种群数量参数输入VORTEX 9.42软件后,得到了与目前的观察值较好的拟合。认为保护区现有的管理措施能够保证该种群长期稳定在环境容纳量水平上,种群100 a内灭绝的概率为0,但不能使种群数量显著增长。影响蛇岛蝮种群动态的主要因素是环境容纳量、死亡率和灾害。如果在环境容纳量水平上,捕取适量的蛇岛蝮个体不会对其种群波动产生较大的影响。改善蛇岛蝮的栖息生境来增加环境容纳量和降低死亡率是使蛇岛蝮种群迅速增加的主要措施,也是今后保护区的主要工作内容。9.濒危机制及保护措施目前蛇岛蝮虽然受到了一定的保护,且具有较好的科研基础和管理手段,但外界环境对岛屿生态系统仍然有干扰。正确处理人、蛇和鸟之间的关系,正确处理保护和经济发展的关系,加大科研力度和管理的有效性,增加林缘比例,防止外来物种入侵,调整植被结构,提高人们的保护意识等等,这是保护蛇岛蝮种群、恢复其种群资源的有效途径。更多还原

【Abstract】 From 2005 to 2006,based on the investigational field data and collectable material,we study the pit-vipers Gloydius shedaoensis that has the representation to the life on Snake Island in China and is an endangered poisonous snake by using wild animals investigation,statistical analysis,silver staining and immunohistochemical,the computer model simulation.The population dynamics,habitat selection,relation between edible birds and snakes,population viability analysis,protection and management of Gloydius shedaoensis are studied on the point of view from the population ecology and conservation biology.The main results in this paper were revealed as following:1.Population size and distribution of Gloydius shedaoensis at presentFor current,the population size of Gloydius shedaoensis is 20 281±590 and most of them are in the sixth ditch and the second ditch,which mainly distributes in the shrub and the meadow.In addition,the distribution of Gloydius shedaoensis is more at the edge of forest, pond,and roadside,nearby stone such as places,while smaller at the jungle and kudzu. Different age groups of Gloydius shedaoensis have different distribution area that the juvenile and the subadult mainly distribute in the shrub and meadow,the adult mainly distributes in the forest,and aged adult mainly in bare land and rock.The main factors of influencing the populations and distribution of Gloydius shedaoensis are food,the type of vegetation,water source and stone,etc.2.Basic parameters of the populationAt present,the sex ratio of female and male of population of Gloydius shedaoensis is 1.11:1.00,the number of effective populations is 15 074 and age structure is that the juvenile 9.66%,subadult 15.81%,adult 61.08%,and aged adult 13.45%.The instantaneous rate of increase and the finite rate of increase respectively are 0.020 4 and 1.0206.It is a stable population and population growth slowly.The estimate value of environmental capacity is 22750.3.Population dynamics changeThe number and distribution of Gloydius shedaoensis changed significantly in spring and autumn.Population has small fluctuation and distribution is permanent and in heaps.It has certain changes in the structure of the population that juvenile and subadult reduce the proportion and aged adult has an increasing proportion.The number growth speed is gradually slowing down;so,the need for further increasing the level of environmental capacity is necessary. 4.Habitat selectionIn order to obtain more opportunities to catch the edible birds,Gloydius shedaoensis has more choices the shrub and forest habitats in sunny and semi-shade semi-sunny,in general, which locate in upper slope location,higher elevation,slopes,moderate vegetation cover, proximity to the forest edge,roads and the mountain ridges.In order to obtain sufficient energy, Gloydius shedaoensis selects habitat conditions with higher temperature,moderate humidity and illumination intensity.It is the most important environmental factors that Gloydius shedaoensis habitat selection is forest edge,roads,mountain ridges and the type of vegetation. The main influencing factors of habitat selection are the availability of food and heat.5.The relationship between Gloydius shedaoensis and edible birdsCurrently edible birds of Gloydius shedaoensis have 9 Order,29 families,99 species,and passerine small birds(body length 20.00～10.00 cm) are the mains.Edible birds have higher population density at the bottom of ditch near the water meadows,bare land and shrub.Body length,number,distribution,the time,which arrives and pause on the island of edible birds influence Gloydius shedaoensis habitat selection and predation rate.Gloydius shedaoensis and edible bird’s population dynamics show significant positive correlation.6.Gastrointestinal endocrine cells of Gloydius shedaoensis and their alimentary canal function adaptationArgyrophilic cells and 5-Hydroxytryptamine immunoreactive cells of Gloydius shedaoensis exist in all parts of digestive tract and have diverse morphology.The distribution of density curve is undee and the distribution density at gastric cardia;duodenum and rectum site is higher which demonstrate that unique diet is suitable for living environmental.7.Artificial feeding and energy metabolismThe snake can be longer suffered from hunger,resting metabolic rate(RMR) is low, energy metabolism relatively is slow,and the discharge peak is seven days after eating.Adult’s digestion and absorption rate are higher,while,the juvenile and the subadult are lower. Artificial feeding liquid food can meet the individual needs of the growth and have a higher survival rate.8.Population viability analysisWhen the parameters of the estimative and forecast population number of Gloydius shedaoensis have been put into VORTEX 9.42 software,we can obtain the better fitting results with the present observation value.The existing management measures of nature reserve can assure this population stabilize in the level of environmental capacity for a long time,which make the extinct probability of this population be 0 within 100 years,but not make the population number obviously increase.The main factors of affecting population dynamics are environmental capacity,mortality and disaster.On the level of environmental capacity,it will have not a tremendous influence on population dynamics of Gloydius shedaoensis by capturing properly.Increasing the environmental capacity and reducing the mortality are the main measures of increasing the population number of Gloydius shedaoensis.Meanwhile,they will be important work contents of nature reserve in future.9.Endangered mechanisms and protection measuresAt present,Gloydius shedaoensis have a certain protection,and have a better basis of scientific research and management means,but species are still endangered.On the one hand, fluctuations of the external environment randomly interfere with the island ecosystems,the other hand,they loss their own genetic diversity and own life history character.Correctly handling the relationship among people,snakes and birds,the relations between protection and economic development,intensifying the research and the effective management,and raising the people’s awareness of protection are the effective way of protecting Gloydius shedaoensis populations and restoring its resources.更多还原