Coral recruit size-escape thresholds under fish grazing

Algae covered tiles containing week-old and month-old coral recruits of Acropora millepora, Acropora kenti and Goniastrea retiformis were exposed to different types of fish grazing to investigate the impact of grazing on coral recruit survival. High resolution images of tiles where used to track recruit size and survival, and algae coverage, pre and post 24 hour exposure to fish grazing. The tested fish grazers were Ctenochaetus binotatus (a 'brusher'), Salarias fasciatus ('brusher'), Acanthurus nigrofuscus ('cropper') and Zebrasoma scopas ('concealed cropper'); also included were a 'control' treatment where tiles were undisturbed for the 24 hours and a 'manual' treatment where algae was removed by an aquarist. After the experiment, fish were anaesthetised and measured. These data were collected in December 2023.

将附着藻类的陶片（其上定植有1周龄和1月龄的微孔鹿角珊瑚（Acropora millepora）、肯特鹿角珊瑚（Acropora kenti）及网状角棒珊瑚（Goniastrea retiformis）的珊瑚幼体）暴露于不同类型的鱼类牧食环境中，以探究牧食作用对珊瑚幼体存活率的影响。研究人员通过高分辨率影像，追踪了陶片在24小时鱼类牧食暴露前后的珊瑚幼体尺寸、存活率及藻类覆盖度。本次实验所测试的鱼类牧食类群包括：双斑栉齿刺尾鱼（Ctenochaetus binotatus，“刮食型”）、带纹跳弹鳚（Salarias fasciatus，“刮食型”）、褐斑刺尾鱼（Acanthurus nigrofuscus，“啃食型”）以及高鳍刺尾鱼（Zebrasoma scopas，“隐蔽啃食型”）；此外还设置了两类处理组：对照组（24小时内陶片不受干扰）与人工处理组（由水族饲养员清除陶片表面的藻类）。实验结束后，研究人员对试验鱼类进行麻醉并测量其形态指标。该数据集采集于2023年12月。