Title: CHANGES IN MESOPHOTIC REEF FISH ASSEMBLAGES IN THE NORTHWESTERN HAWAIIAN ISLANDS ALONG A LATITUDINAL AND LONGITUDINAL GRADIENT

Abstract: Mesophotic coral ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated fauna at depths below 30 m and support a diversity of marine organisms. We investigated changes in the structure of mesophotic reef fish assemblages in the Northwestern Hawaiian Islands (NWHI) along a latitudinal and longitudinal gradient, using survey data from 27 - 92 m depths. There was a clear gradient in the assemblage structure from the southeastern end to the northwestern end of the NWHI. The three atolls at the northwestern end of the NWHI (Pearl and Hermes, Midway and Kure) had higher abundances of two endemic planktivores, Genicanthus personatus and Pseudanthias thompsoni, and a temperate species, Centropyge interrupta, than all other locations. An endemic invertivore, Bodianus sanguineus, was also relatively abundant on deeper mesophotic reefs of these three locations. The two locations at the southeastern end of the NWHI (Nihoa and French Frigate Shoals) were characterized by high abundances of the introduced invasive species, Lutjanus kasmira; this species was only recorded at these two locations with an exception of one individual at Lisianski Island. This study indicates that MCEs in the NWHI can be treated as three regions for monitoring and management purposes: southeastern and mid regions characterized by the presence/absence of the invasive fish L. kasmira, and a northwestern region where fish assemblages, largely composed of endemic species, can be influenced by cooler temperate climate.

Authors: Fukunaga A, Kosaki R, Wagner D

Presentation: Poster (#341)

Session: 29

Date: 06/21/16

Time: 18:15 - 19:45

Location: Poster/Exhibit Hall

Back