Shipwrecks can be considered island-like habitats on the seafloor. We investigated the fauna of 8 historical shipwrecks off the US east coast to assess whether species distribution patterns on the shipwrecks fit models from classical island theory. Invertebrates on the shipwrecks included both sessile (sponges, anemones, hydroids) and motile (crustaceans, echinoderms) species. Invertebrate communities were significantly different among wrecks. The size and distance between wrecks influenced the biotic communities, much like on terrestrial islands. However, while wreck size influenced species richness (alpha diversity), distance to the nearest wreck influenced community composition (beta diversity). Alpha and beta diversity on the shipwrecks were thus influenced by different abiotic factors. We found no evidence of either nested patterns or non-random co-occurrence of morphotypes, suggesting that the taxa on a given shipwreck were randomly selected from the available taxon pool. Species present on the shipwrecks generally had 1 of 2 reproductive modes: most motile or solitary sessile species had long-duration planktotrophic larvae, while most encrusting or colonial sessile species had short-duration lecithotrophic larvae and underwent asexual reproduction by budding as adults. Short-duration larvae may recruit to their natal shipwreck, allowing them to build up dense populations and dominate the wreck surfaces. A high degree of dominance was indeed observed on the wrecks, with up to 80% of the fauna being accounted for by the most common species alone. By comparing the shipwreck communities to known patterns of succession in shallow water, we hypothesize that the shipwrecks are in a stage of mid-succession.

Depth range
68- 125 m

Mesophotic “mentions”
0 x (total of 5779 words)

Classification
* Presents original data
* Focused on 'mesophotic' depth range
* Focused on 'temperate mesophotic ecosystem'

Fields
Biodiversity
Community structure
Connectivity
Ecology

Focusgroups
Actiniaria and Ceriantharia (Sea anemones)
Crustacea
Hydrozoa
Octocorallia (Soft Corals)
Other invertebrates
Porifera (Sponges)

Locations
USA - Continental Atlantic Ocean

Platforms
Remotely Operated Vehicle (ROV)