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It is well known that fish can learn to avoid angling gear after experiencing a catch‐and‐release event, that is, after a private hooking experience. However, the possible importance of social information cues and their influence on an individual's vulnerability to angling remains largely unexplored, that is, social experience of a conspecific capture. The effects of private and social experience of hooking on the stress response of fish and subsequent catch rates were examined. Hatchery‐reared rainbow trout, Oncorhynchus mykiss (Walbaum), were implanted with heart rate loggers and experimentally subjected to private or social experience of hooking. Private and social experience of angling induced an increased heart rate in fish compared with naive control fish. While private experience of hooking explained most of the reduced vulnerability to capture, no clear evidence was found that social experience of hooking affected angling vulnerability in fish that had never been hooked before. While both private and social experiences of angling constitute significant physiological stressors for rainbow trout, only the private experience reduces an individual's vulnerability to angling and in turn affecting population‐level catchability.

Movement ecology is increasingly relying on experimental approaches and hypothesis testing to reveal how, when, where, why, and which animals move. Movement of megafauna is inherently interesting but many of the fundamental questions of movement ecology can be efficiently tested in study systems with high degrees of control. Lakes can be seen as microcosms for studying ecological processes and the use of high-resolution positioning systems to triangulate exact coordinates of fish, along with sensors that relay information about depth, temperature, acceleration, predation, and more, can be used to answer some of movement ecology's most pressing questions. We describe how key questions in animal movement have been approached and how experiments can be designed to gather information about movement processes to answer questions about the physiological, genetic, and environmental drivers of movement using lakes. We submit that whole lake telemetry studies have a key role to play not only in movement ecology but more broadly in biology as key scientific arenas for knowledge advancement. New hardware for tracking aquatic animals and statistical tools for understanding the processes underlying detection data will continue to advance the potential for revealing the paradigms that govern movement and biological phenomena not just within lakes but in other realms spanning lands and oceans. Correction published here, October 2021: https://doi.org/10.1186/s40462-021-00285-3

No abstract available.

The role of shoal familiarity in modulating relationships between individual fish’s metabolic traits and vulnerability to capture in a simulated trawl were tested in the lab. Fish tested in familiar shoals showed a negative relationship between anaerobic metabolic capacity and time spent in the trawl net, but not fish tested in unfamiliar shoals., Impacts of fisheries-induced evolution may extend beyond life history traits to more cryptic aspects of biology, such as behaviour and physiology. Understanding roles of physiological traits in determining individual susceptibility to capture in fishing gears and how these mechanisms change across contexts is essential to evaluate the capacity of commercial fisheries to elicit phenotypic change in exploited populations. Previous work has shown that metabolic traits related to anaerobic swimming may determine individual susceptibility to capture in trawls, with fish exhibiting higher anaerobic performance more likely to evade capture. However, high densities of fish aggregated ahead of a trawl net may exacerbate the role of social interactions in determining an individual fish’s behaviour and likelihood of capture, yet the role of social environment in modulating relationships between individual physiological traits and vulnerability to capture in trawls remains unknown. By replicating the final moments of capture in a trawl using shoals of wild minnow (Phoxinus phoxinus), we investigated the role of individual metabolic traits in determining susceptibility to capture among shoals of both familiar and unfamiliar conspecifics. We expected that increased shoal cohesion and conformity of behaviour in shoals of familiar fish would lessen the role of individual metabolic traits in determining susceptibility to capture. However, the opposite pattern was observed, with individual fish exhibiting high anaerobic capacity less vulnerable to capture in the trawl net, but only when tested alongside familiar conspecifics. This pattern is likely due to stronger cohesion within familiar shoals, where maintaining a minimal distance from conspecifics, and thus staying ahead of the net, becomes limited by individual anaerobic swim performance. In contrast, lower shoal cohesion and synchronicity of behaviours within unfamiliar shoals may exacerbate the role of stochastic processes in determining susceptibility to capture, disrupting relationships between individual metabolic traits and vulnerability to capture.

Human pressure on seashores has induced the installation of many seawalls. Artificial coastal defence structures may be providential for the juveniles of fish species exploited by artisanal fisheries. Focusing on Diplodus sargus, the number of settling juveniles was estimated on artificial structures and on natural rocky shores. The aim is to know if these artificial areas can have a nursery function. Densities of juveniles are from 30 to 109 times greater than those in natural habitats. Artificial coastal defence structures can be regarded as artificial nurseries. However, in the studied case, they also cause the loss of the nursery function of the nearby lagoon. The artificial seawalls at the entrance to the lagoon receive almost all the larvae that would normally enter the lagoon. This study underlines the important role of these artificial habitats in the life cycle of white seabream. They may have a positive impact on maintaining other species exploited by artisanal fisheries.

Corsica Island is a sub-basin of the Northwestern Mediterranean Sea, with hydrological features typical of both oligotrophic systems and eutrophic coastal zones. Phytoplankton assemblages in two coastal ecosystems of Corsica (the deep Bay of Calvi and the shallow littoral of Bastia) show contrasting patterns over a one-year cycle. In order to determine what drives these variations, seasonal changes in littoral phytoplankton are considered together with environmental parameters. Our methodology combined a survey of the physico-chemical structure of the subsurface water with a characterization of the phytoplankton community structure. Sampling provided a detailed record of the seasonal changes and successions that occur in these two areas. Results showed that the two sampled stations presented different phytoplankton abundance and distribution patterns, notably during the winter–spring bloom period. Successions in pico-, nano-, and microphytoplankton communities appeared mainly driven by differences in the ability to acquire nutrients, and in community-specific growth rates. Phytoplankton structure and dynamics are discussed in relation to available data on the Northwestern Mediterranean Sea. These results confirm that integrated monitoring of coastal areas is a requisite for gaining a proper understanding of marine ecosystems.

International audience; In the context of growing anthropogenic disturbances that deeply alter marine coastal ecosystems, various management tools are used to protect biodiversity, such as fishing gear limitations, fishing quotas, protected areas or the creation of artificial reefs (ARs). In contrast to the other management tools, ARs require a modification of natural habitats. We used underwater visual censuses to investigate the effect of habitat modification on the structure of fish communities by comparing a natural reef (NR) to ARs with different habitat complexity. Different fish assemblage descriptors were used to assess species- and functional- and community-level aspects of the assemblages. ARs were rapidly colonized by adult fishes and presented community compositions different from that of the NR. Fish densities and functional richness were higher in the ARs than in the NR. Small isolated artificial structures, such as culverts and box-culverts, had different fish community compositions than more extended and complex structures, demonstrating the effect of structural habitat complexity on fish assemblages. Fish density was higher in small structures, most likely due to habitat isolation and patchiness. This study indicates that ARs which are located along sandy coastal areas with few rocky habitats and under high river nutrient influence, are a suitable habitat for rocky coastal fish communities. Nevertheless, due to higher habitat complexity and lower fishing pressure on ARs, fish communities of an AR functionally differ from those of a NR. Further research is necessary to understand how these differences act on the properties of the ecosystem as well as on local fisheries.

Artificial reefs are used by many fisheries managers as a tool to mitigate the impact of fisheries on coastal fish communities by providing new habitat for many exploited fish species. However, the comparison between the behavior of wild fish inhabiting either natural or artificial habitats has received less attention. Thus the spatio-temporal patterns of fish that establish their home range in one habitat or the other and their consequences of intra-population differentiation on life-history remain largely unexplored. We hypothesize that individuals with a preferred habitat (i.e. natural vs. artificial) can behave differently in terms of habitat use, with important consequences on population dynamics (e.g. life-history, mortality, and reproductive success). Therefore, using biotelemetry, 98 white seabream (Diplodus sargus) inhabiting either artificial or natural habitats were tagged and their behavior was monitored for up to eight months. Most white seabreams were highly resident either on natural or artificial reefs, with a preference for the shallow artificial reef subsets. Connectivity between artificial and natural reefs was limited for resident individuals due to great inter-habitat distances. The temporal behavioral patterns of white seabreams differed between artificial and natural reefs. Artificial-reef resident fish had a predominantly nocturnal diel pattern, whereas natural-reef resident fish showed a diurnal diel pattern. Differences in diel behavioral patterns of white seabream inhabiting artificial and natural reefs could be the expression of realized individual specialization resulting from differences in habitat configuration and resource availability between these two habitats. Artificial reefs have the potential to modify not only seascape connectivity but also the individual behavioral patterns of fishes. Future management plans of coastal areas and fisheries resources, including artificial reef implementation, should therefore consider the potential effect of habitat modification on fish behavior, which could have key implications on fish dynamics. © 2013 Koeck et al.