Potential Impacts of Offshore Oil and Gas Activities on Deep-Sea Sponges and the Habitats They Form.

Sponges form an important component of benthic ecosystems from shallow littoral to hadal depths. In the deep ocean, beyond the continental shelf, sponges can form high-density fields, constituting important habitats supporting rich benthic communities. Yet these habitats remain relatively unexplored. The oil and gas industry has played an important role in advancing our knowledge of deep-sea environments. Since its inception in the 1960s, offshore oil and gas industry has moved into deeper waters. However, the impacts of these activities on deep-sea sponges and other ecosystems are only starting to become the subject of active research. Throughout the development, operation and closure of an oil or gas field many activities take place, ranging from the seismic exploration of subseafloor geological features to the installation of infrastructure at the seabed to the drilling process itself. These routine activities and accidental releases of hydrocarbons during spills can significantly impact the local marine environment. Each phase of a field development or an accidental oil spill will therefore have different impacts on sponges at community, individual and cellular levels. Legacy issues regarding the future decommissioning of infrastructure and the abandonment of wells are also important environmental management considerations. This chapter reviews our understanding of impacts from hydrocarbon exploration and exploitation activities on deep-sea sponges and the habitats they form. These impacts include those (1) at community level, decreasing the diversity and density of benthic communities associated with deep-sea sponges owing to physical disturbance of the seabed; (2) at individual level, interrupting filtration owing to exposure to increased sedimentation; and (3) at cellular level, decreasing cellular membrane stability owing to exposure to drill muds. However, many potential effects not yet tested in deep-sea sponges but observed in shallow-water sponges or other model organisms should also be taken into account. Furthermore, to the best of our knowledge, no studies have shown impact of oil or dispersed oil on deep-sea sponges. To highlight these significant knowledge gaps, a summary table of potential and known impacts of hydrocarbon extraction and production activities combined with a simple "traffic light" scheme is also provided.

A review of Paul Lassenius Kramp's hydrozoan types (taxonomic status, location and condition of the material) and a biography of the Danish zoologist.

During his scientific career, largely from 1910-1970, the Danish cnidarian specialist P.L. Kramp authored 94 scientific papers, and more than 30 other kinds of publications, such as reports and popular articles. Kramp was affiliated with the marine department of the Zoological Museum of the University of Copenhagen (now: The Natural History Museum of Denmark, NHMD), an institution intensely involved at the time in expeditions, in the assembling and maintenance of collections, and in the revision of a wide range of animal groups. Kramp took part in several expeditions in different parts of the world. He had opportunities to receive training in sampling and preservation techniques, to perform observations on living or at least freshly preserved material, and to collect specimens. Kramp dedicated most of his long career to studying the taxonomy of medusae, with some attention also to their polyp stages, describing 101 nominal hydrozoan taxa, including one order, four families and fifteen genera. Sixty-five of these taxa (one order, three families, twelve genera, 48 species and one subspecies) are still accepted in the original nominal form. Kramp raised the international reputation of his museum and his scientific results are still appreciated today.