One mechanism that permits the maintenance of dominance hierarchies is individual recognition, defined as the ability of an animal to recognize a conspecific on the basis of one or more identifying cues, and to associate it with experiences of victories or defeats that the animal has gained from preceding encounters with that particular individual. We examined whether the long-clawed hermit crab, Pagurus longicarpus, could differentiate between unfamiliar and familiar opponents. The experimental protocol was designed to control in pairs of interacting individuals several factors together, such as status and relative size of the opponent, as well as species, quality, and fit of the inhabited shell. The hermit crabs were more reactive and their agonistic level was higher in unfamiliar than in familiar pairs; in addition, betas were more prone to initiate an interaction with unfamiliar than with familiar alphas. The alternative explanation-that the ability to discriminate between familiar and novel shells can explain our results per sewas tested following, in part, Jackson and Elwood's (1989) protocol for Pagurus bernhardus and was, at least for this species, rejected. This study did not determine whether a true individual recognition occurs, but demonstrated that P. longicarpus categorizes the individuals into two "heterogeneous subgroups", thus being capable of a binary discrimination among opponents.

The behaviour exhibited by the hermit crab Pagurus longicarpus in response to an empty shell varied in the presence of cues from conspecific individuals according to its familiarity or not with them. This binary discrimination was independent of the conspecific's relative size and was based on chemical signatures, an ability that this species shares with a few other aquatic invertebrates. From our results, olfaction appeared to be the dominant sensory channel in P. longicarpus' binary discrimination, but the combination of two signal components from visual and olfactory channels resulted in the enhancement of the response displayed by the receiver. Besides, crabs reacted differently when exposed to their own odour than to the odour of familiar (as well as unfamiliar) conspecifics, suggesting that recognition in this species can be more refined than a binary discrimination and that chemical 'badges' may be attributes of individual crabs.

The recreational angling community is comprised of diverse stakeholders, including the trade sector responsible for the manufacturing, distribution, and sales of tackle, boats, and clothing, angler-based travel, revenue-generating popular media, and angling services. Through marketing and promotion, fishing companiescompete for customers by convincing anglers as to what success means when they go fishing. If the angling trade can influence the social norms in the recreational angling community, then this could hold true for norms related to the conservation of recreationally targeted fishes and their habitats. We questioned whether individuals working within the fishing trade are adequately informed about best practices for recreational fisheries conservation, since these perceptions could, in turn, influence the values portrayed in the marketing and promotion of fishing. For this study we surveyed fishing trade employees during five industry and consumer shows to evaluate theirperceptionsaboutrecreational fisheries conservation and where they believe their consumers learn about these issues. Across events,respondents believed that commercial fishing and habitat loss were the greatest threats to recreational fisheries. Specific to the angling event, physical injury when handling (e.g., during hook removal) and duration of the fight were selected as having the greatest impacts on fish, with between 74-91% of respondents indicating that they felt impacts were species-specific. Respondents believed that their customers received information on best practices and conservation predominantly from peer-to-peer interactions, social media, and fishing magazines. They also indicated that one of the primary roles of the angling trade when it comes to recreational fisheries conservation is to convey best practices in marketing and promotion. Overall, the trade sector appears to be an important mechanism for reaching anglers,yet more work is needed to ensure that the conservation information they share is consistent with sciencebased best practice.

Fecal pollution from human and natural sources enters soil or watercourses, mixes, then reemerges as a nuisance of unknown origin. Before remediation is attempted, the sources and identities of pollution must be identified. Previous microbial source tracking studies have relied on traditional methods of microbiology such as selective media and biochemical characteristics to quantify fecal bacteria in water samples. This is successful when single sources are responsible for pollution. However, when multiple sources are present, numbers must be subdivided into categories of pollution to define relative importance and select appropriate methods of remediation which are very different for examples such as humans and avifauna pollution. Rather than depending on a single method, we recommend a tiered approach which takes advantage of ecological parameters and conventional microbiology to provide context for more precise DNA data and related statistics.

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