Benthic marine litter in shallow fishing grounds in the NW Mediterranean Sea.

Fisheries are one of the main economic sectors affected by marine litter, which can damage gear, reduce catch, and require time to repair or clean nets. This study aims to evaluate the type and density of marine litter in two shallow fishing grounds in the NW Mediterranean Sea, both belonging to the Natura 2000 network. Moreover, it quantifies the fraction of marine litter within the total catch to help understand the potential influence of marine litter on fisheries. Two study areas were selected, one in the vicinity of urban populated areas and high navigational traffic and one in a rural site off an agricultural area. The urban area had more benthic marine litter (393 to 198 kg km-2) including clinker (residue from coal-burning steamships), fabric, plastics, and processed wood and accounting for up to 38% of the total catch. The rural area had far less marine litter (34-56 kg km-2), accounting for only 5% of the total catch. Marine litter may have potential negative effects on fisheries; thus we propose that government credit trading programs could be promoted to help recover litter from fishing catches, to reduce fishing costs and hazards to marine ecosystems.

Larval development of the symbiotic pea crab Pinnaxodes chilensis (H. Milne Edwards, 1837) (Decapoda, Brachyura, Pinnotheridae) reared in laboratory.

The complete larval development of Pinnaxodes chilensis (including four zoeal stages and a megalopa stage) is described and illustrated in detail for the first time. The descriptions are based on laboratory-reared larvae obtained from ovigerous females found inside specimens of the sea urchin Loxechinus albus collected in the coast of Valparaíso, Chile. In order to allow the correct differentiation of specimens from plankton samples, the larval stages of P. chilensis are compared with those from other Pinnotheridae species, whose larval development is known for the Chilean continental waters (Calyptraeotheres politus). The morphological characters described for P. chilensis larvae, as well as the comparison with the remaining larval development descriptions available for the genus Pinnaxodes, are used to discuss the heterogeneity within this genus.