Publications:

Wagner et al. 2014


scientific article | Mar Biodivers Rec | open access

Mesophotic surveys of the flora and fauna at Johnston Atoll, Central Pacific Ocean

Wagner D, Kosaki RK, Spalding HL, Whitton RK, Pyle RL, Sherwood AR, Tsuda RT, Calcinai B



Abstract

Despite its extreme geographical isolation, numerous expeditions have surveyed the marine flora and fauna of Johnston Atoll. However, historical information about the marine biodiversity of Johnston is mostly limited to SCUBA surveys in shallow-waters (<30 m), and submersible observations in deeper waters (100–500 m). Extensive coral reefs, known as mesophotic coral ecosystems, exist between these two depth ranges at Johnston, but have remained largely unexplored. We used closed-circuit rebreathers to survey eleven sites at mesophotic depths (32–78 m) surrounding Johnston Atoll. A total of 130 species were recorded, including 99 species of fish, 15 species of corals, nine species of macroalgae, three species of echinoderms, three species of sponges and one species of squat lobster. Most species recorded during our mesophotic surveys have previously been recorded on shallow-water (<30 m) reefs at Johnston, with the exception of one black coral, one zoanthid, one squat lobster, two macroalgae, three sponges, and 22 fish, which represent new records for the atoll. As noted in previous studies, our surveys found a near absence of endemism, and recorded high proportions of species that are also known from the Hawaiian Archipelago. The similarity between the mesophotic biodiversity of Johnston Atoll and Hawai‘i provides further support for the strong connectivity between these two locations highlighted in previous studies.

Research sites

Keywords
Meta-data
Depth range
32- 78 m

Mesophotic “mentions”
41 x (total of 3881 words)

Fields
Biodiversity

Focusgroups
Overall benthic (groups)
Fishes

Locations
USA - Johnston Atoll

Platforms
Diving - Technical Rebreather
Sonar / Multibeam

Author profiles
Randall Kosaki ( 13 pubs)
Richard Pyle ( 20 pubs)
Heather Spalding ( 14 pubs)
Daniel Wagner ( 25 pubs)