Department of Biological Sciences, Macquarie University, Sydney, Australia.
J Fish Biol. 2019 Aug;95(2):520-526. doi: 10.1111/jfb.13982. Epub 2019 May 2.
This study investigated whether captive-reared juvenile Port Jackson sharks Heterodontus portusjacksoni choose to aggregate and if familiarity is one of the mechanisms driving social preference. In a controlled binary-choice experiment, juvenile sharks were given the option to associate or not with unfamiliar conspecifics, or to associate or not with familiar conspecifics. In neither group did juvenile H. portusjacksoni actively choose to associate with conspecifics, but familiarity decreased the proportion of time spent near a conspecific only during the initial phase of the experiment. Treatment (1 or 3 shoal mates), sex and size had no effect on aggregation behaviour. These findings suggest that familiarity is not a driver of social preferences in juvenile H. portusjacksoni, contrary to results in another shark species. Additionally, adult H. portusjacksoni form large aggregations during the breeding season and actively associate with familiar sex and size-matched individuals, thus our results suggest the species undergoes an ontogenetic shift in social behaviour.
本研究调查了圈养幼年杰克逊港鲨鱼 Heterodontus portusjacksoni 是否选择聚集，以及熟悉度是否是驱动社交偏好的机制之一。在一个控制的二元选择实验中，幼年鲨鱼有选择与不熟悉的同种个体或与熟悉的同种个体聚集的机会。在两组中，幼年杰克逊港鲨鱼都没有主动选择与同种个体聚集，但在实验的初始阶段，熟悉度仅降低了与同种个体接近的时间比例。处理方式（1 或 3 个同群伙伴）、性别和大小对聚集行为没有影响。这些发现表明，熟悉度不是幼年杰克逊港鲨鱼社交偏好的驱动因素，这与另一种鲨鱼的结果相反。此外，成年杰克逊港鲨鱼在繁殖季节形成大的聚集，并主动与熟悉的性别和大小匹配的个体聚集，因此我们的结果表明该物种的社会行为发生了发育转变。
