Showing papers in "Arquipelago : Life and Marine Sciences in 2015"

First in situ observations of soft bottom megafauna from the Cascais Canyon head

Abstract: We report the first in situ observations of soft bottom megafauna from the Cascais Canyon head. Observations were collected opportunistically during three technical dives with the ROV Luso between 460-805 m at two locations distanced 1,230 m. The habitats were classified as upper bathyal fine mud. The soft bottom fauna was dominated by burrows of Nephrops norvegicus reaching up to 2.9 burrows/m, a common habitat along the Portuguese continental margin. To our knowledge, densities are the highest ever reported for depths below 300 m. The ichthyofauna at the upper Cascais Canyon is a mixture of lower shelf and upper bathyal species, including Phycis blennoides, Scyliorhynus canicula, Coelorhynchus labiatus/occa and Chimaera monstrosa. Bait release attracted Myxine glutinosa. Surveys in other geological settings of the Cascays Canyon are required to understand more comprehensively the diversity of its sessile and vagile biodiversity.

The polygon moray, Gymnothorax polygonius (Poey, 1875) : A new record from Ascension Island, South Atlantic

Abstract: Ascension Island (07°57′S, 14°22′W) is an isolated volcanic edifice in the South Atlantic. The closest land, St. Helena is approximately 700 miles south with the closest land mass of any size being West Africa, 1000 miles to the east. Approximately 1500 miles west of Ascension Island is the coast of Brazil. As such, the fish community of the island is a mixture of eastern and western Atlantic species, although richness is relatively low compared with other similar locations such as Cape Verde (Wirtz et al. 2014). Despite the apparent remoteness of Ascension Island there have been several key publications on the ichthyofauna for the island and surrounding marine zone. The fish community of Ascension was first summarized by Cadenat & Marchal (1963), with a comprehensive checklist of shallow-water fish species published by Lubbock (1980) recording 71 species. A report on the benthic and nearbenthic fish community, from seamounts around Ascension, was compiled in Trunov (2006). The most recent review of the ichthyofauna of Ascension can be found in Wirtz et al. (2014), a study listing 173 fish species, including 12 members of the family Muraenidae. The extensive rocky marine habitat of Ascension Island is often considered a key factor behind the considerable abundance of moray eels around the island. On 21 Feburary 2015 an unidentified moray eel was caught by a recreational angler who had been fishing in deep water from a vessel off the western coast of Ascension Island (Fig. 1). The specimen did not match any previous identification records of Muraenidae from Ascension Island.