鸟类的扩散行为研究进展

扩散是生物个体之间相互远离的单线性运动,是生物的基本特征之一,对种群的分布、动态及遗传结构等方面均有重要影响.扩散有出生扩散和繁殖扩散等主要形式.动物发生扩散的主要原因包括:避免近亲繁殖、减少竞争、改变繁殖地点等.近年来,扩散已经成为鸟类学研究的前沿领域.评述了鸟类扩散行为的性别差异、体质对于扩散的影响,阐述了扩散的基本过程及栖息地选择、长距离扩散等内容,同时介绍了环志标记、无线电遥测、分子生物学等研究鸟类扩散的主要方法.展望了鸟类扩散研究的发展趋势,认为新技术和新方法的应用将成为扩散生态学家关注的重要问题,未来研究将更加重视对鸟类扩散理论问题的探讨,而对鸟类扩散行为的研究成果也会更广泛地应用于濒危物种及其栖息地的保护工作中.

Research progress in avian dispersal behavior

Dispersal, defined as a linear spreading movement of individuals away from others of the population is a fundamental characteristic of organisms in nature. Dispersal is a central concept in ecological, behavioral and evolutionary studies, driven by several forces such as avoidance of inbreeding depression, density-dependent competition and the need to change breeding locations. By effective dispersal, organisms can enlarge their geographic range, and adjust the dynamic, sex ratio and genetic structure of a population. Birds are one of the groups that are studied intensively by human beings. Due to their diurnal habits, diverse life history strategies and complex movement, birds are also ideal models with which to study dispersal behaviors. Such studies on avian species represent a new frontier of ornithological research.
Dispersal is distinguished between natal dispersal and breeding dispersal. The former refers to the movement between the natal area and the first breeding site. Breeding dispersal is the movement between two successive territories. The main objective of avian dispersal research is to obtain the proximate and ultimate perspectives in a diversity of bird species. Certain topics of avian dispersal including sex-biased, asymmetric dispersal caused by differences in body conditions, dispersal processes, habitat selection and long distance dispersal are discussed here. To collect data of parameters of dispersal like distance and rate, it is sensible to mark individuals. Bird-banding or marking, radio-telemetry and genetic markers are useful tools widely applied in many studies. Moreover, satellite-tracking, stable isotope analysis and hormone examination are methodologies currently underway.
A number of empirical studies on avian dispersal have been published in recent years, proving it to be an active field in ornithology. The challenges that surround theories and methodologies impel scientists to continue their studies by following three aspects: (1) furthering methodological advances, (2) strengthening theoretical research, and (3) applying research into the conservation efforts for threatened birds and the management of their habitats.