"被群居"生活对独居物种的影响——以獐(Hydropotes inermis)为例

Chinese water deer (Hydropotes inermis, CWD) was known as an ancient cervids and also a solitary animal. It is reintroduced to Shanghai as a way to recovery this endangered species. During the breed and translocation, the deer have to live in group. As a solitary species, do they adjust survival strategy to be more adaptive or still keep their solidary character? Do they co-operative or commination as social animal when they in group? Solitary animal easy to display stereotyped behavior when they in captivity. Does it happen on the captive CWD when they relocated and breed for release? When they were released, does CWD re-establish home range affected by “neighbors”? To answer these questions, we measure the common behaviors, mating behaviors, parental care of “group living” CWD and the activity rhythm, home range of CWD after releasing. We will compare the relationships between individuals during different live period as non-rating season, ratting season and nursery season to discover the fitness cost and survival strategy. These results will not only to study the solitary evolution and influence factors to CWD, also help the CWD to re-establish and restore the population.

獐（Hydropotes inermis）是古老的鹿科动物，也是我国国家二级保护动物，上海地区采用了重引入方式恢复该物种。作为独居鹿科动物獐，在重引入过程中，其经历圈养建群扩繁、野化、野放阶段，作为独居动物，在其“被群居”状态中其怎样的行为适应，以及对其生存策略会有怎样的影响呢？獐将保持其独居特性，还是会出现合作繁育、通讯等群居行为？在圈养状态中，是否会出现刻板行为？在野放后，“邻居”是否影响其家域形成？带着这些问题，我们采用行为观察、激素分析、遥测跟踪等手段，来测量獐在“被群居”的圈养和半散养状态的日常行为、繁殖行为、育幼行为，及野放后的活动节律、家域。通过在非繁殖、繁殖、育幼等时期的行为规律和个体相互关系来探究獐的是否存在被动调整，是否影响动物的生存策略和适合度，这关系獐野放后的种群建立与恢复，关系其保护方案的实施效果。

通过行为观察、激素分析、遥测跟踪等行为学研究手段来了解了独居鹿科动物獐在“被群居”状态及此后回归野生状态过程中的生存策略。研究发现：獐的活动节律、警戒距离会随环境的变化而波动，其警戒模式中出现吼叫行为，疑似在群居状态下对其它个体的警示。雄性领域行为明显，并在发情期显著升高，睾酮的变化与擦额标记、粪尿标记、威胁和打斗行为显著正相关。在育幼期间，雌性会出现帮亲行为，幼獐在出生2周后开始独立觅食，6周后警戒行为明显。在经历被群居野放后，雄性全部出现明显扩散行为，雌性只有33%有明显扩散行为，野放初期的平均扩散距离为623 m。野放的獐在扩散后会形成各自家域。采用最小凸多边形法（MCP）计算南汇东滩野放獐后的家域平均为670.93 ± 351.90 ha，其个体间差异为245.47ha-1559.13ha。个体间家域重叠显著，其平均重叠面积为302.55±227.39ha，雄獐的平均家域重叠面积为134.92±135.31 ha，雌獐的平均家域重叠面积为422.11±207.73 ha。家域高度重叠可能与群居生活史相关。