Title: USE OF MESOPHOTIC CORAL ECOSYSTEMS BY INVASIVE WESTERN ATLANTIC LIONFISH

Abstract: The severe negative effects of invasive lionfish (Pterois volitans and Pterios miles) on western Atlantic shallow reefs are well documented, yet despite lionfish recorded on deeper reefs, the use of mesophotic coral ecosystems (MCEs) in invasive lionfish ecology and life history remains a significant gap in our knowledge. We combine studies of lionfish abundance and body length on shallow (0-30m) and mesophotic (30-150m) reefs from 63 sites in seven western Atlantic countries. Lionfish were found at similar abundances on adjacent shallow and mesophotic invaded reefs and in some locations MCE lionfish were larger than shallow individuals. This suggests MCEs may form part of a natural ontogenetic migration, with older lionfish found at greater depths. To further understand these patterns we conducted detailed lionfish surveys around Utila, Hondruas from 5-85m depth during June-September 2015. Our results indicate a depth refuge around Utila, with greater densities of larger lionfish recorded on MCEs than shallow reefs. We took detailed measurements and dissection data of circa. 500 lionfish across this depth range. Male lionfish were found to be more reproductively mature on MCEs than shallow reefs, though interestingly reproductive maturity and mean gonad weight was not found to be different with depth for female lionfish. This study highlights the need for lionfish adaptive management to consider lionfish populations below the depth limit of recreational SCUBA diving, as the focus of most previous control (culling) measures has been shallow water.

Authors: Andradi-Brown DA, Hendrix A, Grey R, Rogers AD, Exton D

Presentation: Oral

Session: 29

Date: 06/22/16

Time: 16:45

Location: 308 A/B

Back