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"Based on the research expertise of leading scientists, Commercial Fishing: The Wider Ecological Impacts provides an account of fishing activities and their impacts on marine habitats, biodiversity and species of conservation concern. It covers fishing methods that range from trawling in the Antarctic to fishing with dynamite in the tropics. The authors show how habitats such as the muddy sea beds of the deep sea, kelp forests and coral reefs are affected by fishing and how birds, mammals, turtles and sea snakes both suffer and benefit from fishing activities. They also look to the future, highlighting ways to make fishing gears 'environmentally friendly' and asking whether marine reserves will improve conservation."--Jacket

Maerl beds occur worldwide and are formed by an accumulation of unattached calcareous red algae (Rhodophyta). Maerl-forming algae grow in a superficial living layer on sediments within the photic zone. Maerl beds are spatially complex habitats with a high degree of species and trophic group diversity. The European Commission's 'Habitats Directive' mandates the conservation management of two of the main European maerl-forming species, Phymatolithon calcareum and Lithothamnion corallioides. Mediterranean maerl beds are to be considered for inclusion in national inventories of sites of conservation interest, as required by the SPABIM Protocol of the Barcelona Convention. In spite of their importance, and the requirement for their conservation management, European maerl grounds suffer a variety of anthropogenic perturbations including direct exploitation through extraction, fishing impacts and chemical pollution by organic matter and excess nutrients. The ecology of northeast Atlantic and Mediterranean maerl beds has received little attention, in contrast to other marine communities (e.g. kelp forests, sea-grass meadows). Key conservation and management measures proposed include: the recognition that maerl beds are non-renewable resources and cannot sustain direct exploitation; prohibitions on the use of towed gear on maerl grounds; moratoria on the issue of further permits for the siting of aquaculture units above maerl grounds; monitoring of existing exploited or impacted maerl beds; the designation of 'no-take' reserves; measures to limit the impacts that might affect water quality above maerl beds; a programme of monitoring of the 'health' of European maerl beds; an awareness campaign on the biological importance of maerl beds; a higher conservation status for maerl habitats and maerlforming species in European legislation; and further research on maerl ecosystems. ; peer-reviewed