Both trammel and gill nets are used to catch marine fishes and crustaceans around the British Isles. Their use is controversial in areas where there is a risk of incidental catches of seabirds or marine mammals. An additional concern is the fate and fishing capabilities of nets when they are lost either as a result of bad weather or when they are damaged by mobile fishing gear. Few, if any, studies have ascertained for how long or effectively these lost nets continue to fish, more commonly termed 'ghost fishing' Two types of fixed gear, a gill and trammel net, were set by a commercial fisherman ca 1000 m offshore from a rocky coastal area in southwest Wales, UK. One end of each net was cut free to simulate net loss. The nets were then allowed to fish continually for 9 mo, during which time they were surveyed by divers recording catches by direct observation, still photography and video camera survey. Several hours after both nets had been set, a large number of dogfishes were caught, causing the nets to collapse. Within 1 d. 2 commercial crustacean species, spider crabs Maja squinado and brown crabs Cancer pagurus, were attracted to the dead and decomposing fishes. Many of these an]-mals also became trapped in the netting and were fed upon by their conspecifics and other scavengers. Some of these crustaceans also became entangled and died, producing a sequence of captures throughout the observation period. Catch rate began to decline within a few days of the initial deployment, probably related to a decl~ne in the effective fishing area. The results indicate that lost nets could continue to catch commercial crustacean specles for at least 9 n~o after initial loss.

The management of the marine environment requires effective temporal monitoring of communities and assemblages to detect any change above the level of natural variability. Even though sponges are usually abundant in subtidal hard substratum environments and have the ability to significantly influence other community members, they have often been excluded from monitoring programmes because they are taxonomically difficult and often hard to quantify compared to other marine groups. We consider the use of a morphological method to examine photoquadrat data collected at 3 hard substratum sites over a 10 yr period at Skomer Marine Nature Reserve, south-west Wales. Differences in the morphological assemblages and abundance were apparent between years, but the sponge assemblages showed rapid recovery (within 1 yr) to their original assemblage composition and abundance following declines. The changes were attributed to natural biological variation or a short-term impact, rather than any response to prolonged environmental change and there was no correlation between any of the changes in assemblages observed and the environmental variables measured. A comparison of morphological and species data enabled the same sponge assemblages to be identified at different sites, validating the method. This morphological approach to monitoring represents a cost-effective and realistic way of monitoring certain sponge assemblages.

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Grey seals (Halichoerus grypus) are a qualifying feature of three special areas of conservation (SACs) in Wales, yet relatively little is known of their site use along this coastline. Since 1992, many individuals and organisations have contributed to a grey seal photographic identification database held by Natural Resources Wales, which is one of the largest and oldest of its kind, providing key information from grey seal haul-out sites around the Celtic and Irish Seas. Here, we investigated spatial connectivity of haul-out sites and fidelity of adult females to breeding sites. The minimum number of adult female grey seals using the area between 1992 and 2016 was 2688. Individual capture histories and relative spatial transition probabilities (P ij) between pairs of location groups were calculated. Adjacent locations were highly connected (e.g. Lleyn Peninsula and Bardsey, P ij = 0.7) but connections spanned the entire region, up to 230 km apart (e.g. Skomer and Dee Estuary, P ij = 0.004). Resights were recorded within SACs (e.g. Lleyn Peninsula and Bardsey [Lleyn Peninsula and the Sarnau SAC], P ij = 0.7), between SACs (e.g. Bardsey and Skomer [Pembrokeshire Marine], P ij = 0.03), between SACs and non-designated areas (e.g. Skerries and Bardsey, P ij = 0.09) and between sites outside any protected area (e.g. Dee Estuary and Anglesey, P ij = 0.5). While inter-annual fidelity to breeding sites was high (P ij = 0.82-1), individual female grey seals moved throughout the region. This evidence of extensive site use beyond protected areas is important for the management and conservation of grey seals around Wales.