Responses of Bugula neritina, an arborescent bryozoan to the effects of real and imitation predation events by the nudibranch Polycera hedgpethi

For colonial organisms physical damage or predation can result in the loss of part of the colony. Although the colony may survive, loss of part of the colony may alter patterns of growth and reproduction. In this study the response of Bugula neritina, an arborescent bryozoan, to physical damage was tested in three experiments: 1) short term regenerative responses to the removal of zooids from growth tips; ii) growth and reproductive responses to damage imposed at different locations within the colony and iii) the effects of damage produced by a natural predator the nudibranch Polycera hedgepethi. This dataset gives the growth and reproductive responses of B. neritina colonies over a four week period in February 2000 following three treatments: i) a single predation event by P. hedgepethi; ii) an imitation predation event and iii) no damage. Each of the three experimental treatments was carried out on twenty immature B. neritina colonies under laboratory conditions; the colonies were then returned to the field site at Williamstown, Victoria. Neither predation by P. hedgepethi nor imitation predation resulted in any significant change in growth, onset of reproduction or reproductive output in B. neritina.

对于群居生物而言，物理损伤或捕食行为可导致其群体部分结构脱落。即便群体得以存活，部分结构的脱落仍可能改变其生长与繁殖模式。本研究以膜孔苔虫（Bugula neritina）——一种树状苔藓虫（arborescent bryozoan）——为研究对象，通过三项实验探究其对物理损伤的响应：1）从生长顶端移除个员（zooid）后的短期再生响应；ii）针对群体不同位置施加损伤所引发的生长与繁殖响应；iii）由天然捕食者裸鳃类（nudibranch）赫氏多角海牛（Polycer hedgepethi）造成的损伤所产生的影响。本数据集记录了2000年2月为期4周内，膜孔苔虫（B. neritina）群体在三种处理方式下的生长与繁殖响应：i）赫氏多角海牛（Polycer hedgepethi）单次捕食事件；ii）模拟捕食事件；iii）无损伤处理。三项实验处理均在实验室条件下对20株未成熟的膜孔苔虫（B. neritina）群体开展，随后将这些群体放回至维多利亚州威廉斯敦的野外采样点。赫氏多角海牛捕食与模拟捕食均未对膜孔苔虫的生长、繁殖起始时间及繁殖产出产生显著影响。