Effects of a Wave Power Park with No-Take Zone on Decapod Abundance and Size

Past studies have revealed higher levels of biodiversity, total abundance, and size ofindividuals around offshore installations of renewable energy. This study investigated the effectsof Lysekil wave power park (area 0.5 km2) on the abundance and carapace size of decapods at theSwedish west coast. For that purpose, decapods were caught with cages during four consecutivesummers. Two types of cages were applied to catch a wide range of decapod species and sizes. Theabundance and size of decapods were not significantly different within the wave power park and upto a distance of 360 m outside of it. The catch rate, i.e., number of decapods caught in 24 h, was notsignificantly different among sampling locations but revealed inter-annual variation for both cagetypes. The results suggest a limited role of the incidental no-take zone of the small Lysekil wavepower park on the abundance and size of local decapods. However, neither were negative impacts,such as decreasing abundances or smaller carapace sizes, discovered. As an increase in the numberof marine renewable energy production sites is foreseen, a scaled-up and larger study addressingMPA networks and other environmental interactions should be considered