Habitat association and distribution of Nauticaris marionis at the Sub-Antarctic Prince Edward Islands

• Main Author: Haley, Craig
• Other Authors: Atkinson, Lara Jane, Von der Meden, Charles, Reed, Cecile C
• Format: Master Thesis
• Language: English
• Published: University of Cape Town 2016
• Subjects: Zoology; Marine Biology; Antarctic; Antarc*; Prince Edward Islands
• Online Access: http://hdl.handle.net/11427/20471; https://open.uct.ac.za/bitstream/11427/20471/1/thesis_sci_2016_haley_craig.pdf

The habitat associations between the caridean shrimp Nauticaris marionis and sessile epibenthic assemblages and substratum types of the Sub-Antarctic Prince Edward Islands were investigated. Twenty five stations, varying in substratum type, depth and location on the shelf and slope around the islands were sampled photographically with a towed benthic camera sled. At each station the substratum type was classified, sessile epibenthic cover was quantified through the use of digital quadrats and shrimp density was estimated. Results add to the broadly described distribution patterns of N. marionis by identifying specifically the habitat characteristics they generally utilize. The distribution of N. marionis was found to be influenced by a combination of substratum and sessile epibenthic assemblages, but not substratum type alone. Shrimp inhabited stations with >50 % biogenic cover on mud and gravel substrata, but were not found at stations with rocky-sand or rocky-mud substrata. Their distribution appears to also be influenced by depth, as shrimp were only found within a depth range of 50 - 160 m in this study. A strong correlation was found between N. marionis density and depth. Shrimp were found both inshore around the islands, and on the relatively shallow saddle between the islands. In comparison with previous studies, N. marionis was found at similar, if not higher, densities in this study, although they occupied a narrower depth range.