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Coral mortality may result in macroalgal proliferation or a phase shift into an alga-dominated state. Subtidal, high-latitude western Indian Ocean coral communities at Sodwana Bay on the KwaZulu-Natal coast, South Africa, have experienced some mortality because of warm-water anomalies, storms and other causes, but the response of the macroalgae is unknown. We investigated the abundance and diversity of benthic algae on different hard natural substrata (dead digitate, brain and plate corals and beach rock) on Two-Mile Reef, Sodwana Bay. We also compared algal communities colonising ceramic, marble and pretreated ceramic tiles placed on the reef for six months. We identified 95 algae (14 Chlorophyta, 11 Phaeophyceae, 69 Rhodophyta and one cyanobacterium). Assemblages on natural and artificial substrata were dominated by the brown algaLobophora variegata(Lamouroux) Womersley ex Oliveira and non-geniculate corallines (Rhodophyta, Corallinaceae). Cluster and ordination analyses revealed that the algae showed no affinity for particular substrata, whether natural or artificial. Algal cover was occasionally higher on rougher tiles and crustose corallines were significantly more abundant on marble than ceramic tiles. Two-Mile Reef had 23.1% dead and 48.4% live scleractinian coral cover, where dead corals were colonised indiscriminately by many small algal species, but there was no evidence of algal proliferation. The results provide a baseline for monitoring this high-latitude reef system. [ABSTRACT FROM AUTHOR]

An evaluation of all species of the genusHanleyashowed that they only inhabit the Atlantic Ocean, occurring from off Brazil (25°44′S) to the Barents Sea (74°27′N). The majority of records refer toH. nagelfarwhich ranges from 9°03′8′′N to 74°27′N in coastal waters of North America, Europe and Africa. There are six Recent species ofHanleya:H. tropicalisDall, 1881,H. brachyplaxJardim and Simone, 2010b,H. harasewychisp. nov,H. mediterraneasp. nov,H. hanleyi(Bean in Thorpe, 1844) andH. nagelfar(Lovén, 1846). The phylogenetic relationship ofH. hanleyiandH. nagelfarhas long been questioned. New data on age variability ofHanleya nagelfarare provided.Hanleya hanleyiis the only species of the genus that also occurs in the intertidal zone. All other members ofHanleyainhabit mainly bathyal or sublittoral depths:H. nagelfar(28–1680 m),H. tropicalis(230 m),H. brachyplax(250–408 m),H. harasewychi(73–115 m),H. mediterranea(50–200 m). http://zoobank.org/urn:lsid:zoobank.org:pub:CB8027AC-6755-4F44-9A02-D5C539D84D1F [ABSTRACT FROM AUTHOR]

A new species of marine Gastrotricha,Urodasys poculostylissp. nov. (Macrodasyida: Macrodasyidae), is described from the sublittoral sediments of Capron Shoal, Florida. The new species is a simultaneous hermaphrodite with a single left testis, a stylet bulb and a frontal organ. The stylet bulb bears a cup-shaped sclerotic stylet up to 20 µm long. Several specimens possessed a large spermatophore within the frontal organ.Urodasys poculostylissp. nov. can be further distinguished by the presence of three pairs of anterior adhesive tubes distributed in two rows, 14–17 pairs of lateral adhesive tubes with staggered insertions, 5–7 pairs of ventrolateral adhesive tubes, 12–15 pairs of dorsolateral adhesive tubes and two dorsal adhesive tubes. [ABSTRACT FROM AUTHOR]

The heart rate and calpain activity of blue mussels Mytilus edulis from the sublittoral zone, exposed to different levels of water-borne copper and cadmium, was investigated in a long-term experiment. The content of cadmium and copper in the blue mussel was determined using flame and graphite Atomic absorption spectroscopy. The observed concentrations ranged from 2.5 to 89.1 μg/g dry weight for cadmium and from 6.1 to 51.0 μg/g dry weight for copper in the control and highest concentration, respectively. Initially, increase in cardiac activity in response to copper and Cadmium exposure was observed under all pollutant concentrations (5–250 and 10–500 μg/L, respectively). The calpain-like activity in gills and hepatopancreas of the mussels treated with metals changed in dose- and time-dependent manner: from a sharp rise at the 250 μg/L concentration of copper on the first day to a significant decrease under the effect of Cadmium in the concentration of 500 μg/L on the third day of the experiment. These results suggest that: (i) heart rate oscillation may reflect active adaptation of blue mussels to contamination and (ii) animals have different sensitivity to copper and Cadmium according to the role of the metals in the mussels’ life activity. [ABSTRACT FROM PUBLISHER]

This paper provides the first published record of Lepidodasys, a marine gastrotrich genus, from the Pacific. Two new species of Lepidodasys are described from the sublittoral sandy bottom off Tsushima Island, Japan, with morphological comparisons under scanning electronic microscopy. Lepidodasys laeviacus sp. nov. is allied to L. martini Remane in sharing the herring-bone pattern of the oval scales, but it is distinguished from the latter by the smooth scales lacking keel and the irregular array of 7-10 dorsal adhesive tubes in the trunk region. Lepidodasys tsushimaensis sp. nov. has cuticular armature with parallel orientation of smooth suboval scales, and is further characterized by 6-9 dorsal adhesive tubes along the median line in the intestinal region and ventrolateral adhesive tubes restricted in the pharyngeal region. A key to species of the genus Lepidodasys is provided. [ABSTRACT FROM AUTHOR]

The Pacific red alga Heterosiphonia japonica has dispersed rapidly along European shores. Due to the species' high abundance in many habitats, an impact on species richness and composition of local macroalgal communities might be expected. Higher sea temperatures may also influence local macroalgal composition, by providing more favourable conditions for species requiring higher temperatures. Macroalgal composition at 22 sublittoral sites along the south-western coast of Norway investigated prior to the establishment of H. japonica (1994-1995) were reinvestigated in 2003-2004, using similar methods. The total number of species collected in the area was approximately the same in the present investigation as in the previous study. With regard to number and composition of species at each site, there were no significant differences between sites with high abundance of H. japonica and sites with low or no abundance. Similarity percentage analysis (SIMPER) showed that there were temporal changes in composition of the macroalgal communities, mainly caused by higher frequency of 'southern species' (species with a northern limit on our coast). There was a significant increase in the percentage share of such species in the reinvestigations. The temporal differences observed are most likely caused by several warm summers/autumns and mild winters since the first investigation, which may favour a higher abundance of 'southern species'. Heterosiphonia japonica was the most important species contributing to temporal dissimilarity in the area. This paper concludes that H. japonica has caused no negative impact on regional algal species richness in the relatively short time span since its introduction. [ABSTRACT FROM AUTHOR]

This research compared the ability of Landsat ETM+, Quickbird and three image classification methods for discriminating amongst coral reefs and associated habitats in Pacific Panama. Landsat ETM+ and Quickbird were able to discriminate coarse and intermediate habitat classes, but this was sensitive to classification method. Quickbird was significantly more accurate than Landsat (14% to 17%). Contextual editing was found to improve the user's accuracy of important habitats. The integration of object-oriented classification with non-spectral information in eCognition produced the most accurate results. This method allowed sufficiently accurate maps to be produced from Landsat, which was not possible using the maximum likelihood classifier. Object-oriented classification was up to 24% more accurate than the maximum likelihood classifier for Landsat and up to 17% more accurate for Quickbird. The research indicates that classification methodology should be an important consideration in coral reef remote sensing. An object-oriented approach to image classification shows potential for improving coral reef resource inventory. [ABSTRACT FROM AUTHOR]

Specimens of Tubulanus riceae new species (Nemertea: Palaeonemertea) were collected from a Phragmatopoma worm reef in the surf zone at Fort Pierce (Florida, USA) and from sublittoral rubble at Carrie Bow Cay (Belize) and Bocas del Toro (Panama). They have well‐developed lateral sensory organs, form a cellophane‐like tube and appear to have ocelli‐like structures. The latter, if confirmed as ocelli, would be the first reported for a tubulanid. The new species is characterized by a unique color pattern, resembling that of Tubulanus rhabdotus , but it is distinctive in its milky‐tan ground color with annular bands of brown pigment bounded by white margins and in having up to six to eight dorsal, longitudinal, but broken, reflective white stripes. [ABSTRACT FROM AUTHOR]

Scottish Natural Heritage (SNH) is working, in collaboration with the other Country Agencies and the Crown Estate through the Broadscale Mapping Project (BMP) hosted at the University of Newcastle-on-Tyne, on the development of techniques for marine biotope mapping. The aim of this project is to develop a working tool to carry out comprehensive broad scale mapping surveys of sublittoral habitats and communities (or biotopes). Reliable marine benthic information, at a suitable level of detail, is required by SNH in its work in conservation management of coastal ecosystems. Increasingly it is required to assist with the implementation of the EC Habitats Directive through the identification, designation, management and monitoring of Special Areas of Conservation (SACs) and for the protection of threatened species. The work to date has developed a survey strategy which employs a basic, low-cost acoustic system to produce maps, ground-truthed using a variety of techniques. The maps provide an estimation of the geographical distribution and extent of the biological resources in the survey area. The current paper provides a review of the areas covered to date and some examples of the use this information, in particular the resource maps, has been put to by SNH to support environmental management. [ABSTRACT FROM AUTHOR]

Relates the results of a quantitative survey of sublittoral organisms in polluted and unpolluted waters near Marseilles, France. Low biomass of the Mediterranean sea grass in the polluted Gulf of Marseilles compared with unpolluted bays near Marseilles; Low number of crops in shallow water; Absence of sea grass along the most polluted coastline near the main sewer outlet at Cortiou.