Abstract
Biotic interactions are fundamental to the structuring of marine communities. Predator-prey and competitive interactions can drive species distribution, abundance and mediate individual behaviour. These interactions are especially important to understand in the context of restoration. There is little known about the relationship between three marine invertebrates that commonly co-occur around New Zealand: blackfoot abalone (Haliotis iris), Cook's turban (Cookia sulcata) and the seven-arm sea star (Astrostole scabra). Here, we describe the distribution and feeding behaviour of these species in a customary fisheries management area, the East Otago Tai & amacr;pure, where H. iris has been the focus of restoration. Using field surveys and laboratory experiments, we aimed to understand whether interactions among these species could threaten H. iris recovery. Field surveys conducted in 2012 and 2023 suggested no significant relationship between the densities of H. iris relative to C. sulcata and A. scabra; however, a significant decline in H. iris between years was observed at one site. Laboratory experiments meanwhile found overlapping feeding preferences for H. iris and C. sulcata, no significant differences in grazing rates between H. iris and C. sulcata and direct and indirect effects of A. scabra presence on H. iris. This study highlights the importance of considering biotic interactions in management and adds to the literature on C. sulcata and the A. scabra, of which there is little.