Fish predation on sea urchins on the Great Barrier Reef

摘要: Predators are important for regulating adult sea urchin densities. Here, we employ remote underwater video cameras to record diurnal predation on tethered urchins at Lizard Island the Great Barrier Reef (GBR). We identified four fish predators of (Balistoides viridescens, Balistapus undulatus, Lethrinus atkinsoni and Choerodon schoenleinii). Predator activity appeared be site-specific. Balistoides viridescens B. undulatus (f: Balistidae) were two most Echinometra mathaei with former handling E. significantly faster (mean 0.7 min) than (5.2 min). also successfully preyed 70 % detections, while C. schoenleinii, L. just 33, 17 <1 %, respectively. Additionally, behaviourally dominant among predator species observed as aggressors in 30 encounters 8 atkinsoni. In only one encounter was recipient any aggression (from undulatus). terms relative vulnerability, three examined, more vulnerable Diadema setosum or Echinothrix calamaris, mean times 1.2, 4.8 10.3 min, both appear able play an role relatively intact coral reefs Island. However, emerge efficient speed proportion detections upon. They predator. This preliminary study GBR highlights potential significance scarce but functionally species.