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The conservation and management of marine ecosystems hinge on a comprehensive understanding of the status and trends of top predators. This review delves into the ecological significance of marine top predators, examining their roles in maintaining ecosystem stability and functioning through an integrated analysis of current scientific literature. We first assess the efficacy of various monitoring methods, ranging from traditional field observations to cutting-edge technologies like satellite tracking and environmental DNA (eDNA) analysis and evaluating their strengths and limitations in terms of accuracy, spatial coverage, and cost-effectiveness, providing resource managers with essential insights for informed decision-making. Then, by synthesizing data from diverse marine ecosystems, this study offers a comprehensive overview of the trends affecting top predator populations worldwide. We explore the multifaceted impacts of human activities, climate change, and habitat degradation on the abundance and distribution of these key species. In doing so, we shed light on the broader implications of declining top predator populations, such as trophic cascades and altered community structures. Following a thorough assessment of successful strategies for reversing the decline of top predators, a compilation of recommendations is presented, encompassing effective governance interventions. A crucial aspect of effective ecosystem-based management is the implementation of robust monitoring strategies. Mitigation measures are imperative to reverse the adverse impacts on marine top predators. We present a comprehensive array of mitigation options based on successful case studies. These include the establishment of marine protected areas, the enforcement of fisheries regulations, and the promotion of sustainable fishing practices. We deepen the synergies between these strategies and their potential to mitigate human-induced stressors on top predator populations to safeguard their

The digitalization of society is providing new opportunities to track spatio-temporal redistribution of species across national boundaries in near real-time. This is particularly interesting for marine species for which dynamics are difficult to monitor. We took advantage of the ongoing northward distributional range shift of the white grouper Epinephelus aeneus in Italy, Spain and France (Mediterranean Sea) to test the performance and complementarity of 4 emerging digital methods: (1) local ecological knowledge of recreational fishers actively collected using social media; (2) passive data mining of recreational fishing on social media; (3) Wikipedia page views; and (4) Google search volumes. We compared the temporal changes in maximum latitude of occurrence of the species from local ecological knowledge, passive data mining and traditional scientific knowledge and matched it with the thermal habitat of the species. Moreover, we compared the Wikipedia page views and Google search volumes to assess whether societal interest has a relationship with the distributional range shift of the species. Local ecological knowledge and passive data mining on social media complement traditional scientific knowledge, but are more sensitive as suggested by their significant relationship with the thermal habitat of the species. Wikipedia page views and Google search volumes were higher in Italy where the species is more common, but temporal trends within countries did not agree with changes in the distribution, and likely reflect local societal interest. Digital methodologies can complement traditional scientific knowledge with limited associated costs and with the additional ability to provide social insights for species on the move

In the Western Mediterranean Sea, forage fishes have changed in abundance, body condition, growth, reproduction, and distribution in the last decades. Different hypotheses have been proposed to explain these changes, including increase in fishing mortality; changes in environmental conditions affecting species fitness, and planktonic productivity and quality; recovery of top predators; and increase in competitors. We investigated the main drivers and changes of the pelagic ecosystem and their effects using an ecosystem-based modelling approach. Specifically, we (1) quantified the potential historical contribution of various drivers of change, (2) investigated changes in temporal trends and spatial distributions of main ecosystem components, and (3) identified ecological consequences of these changes in top predator and competitors, their fisheries and ecosystem traits during 2000–2020. We updated an established Ecopath food-web model representing the Spanish and French Mediterranean sub-areas (GSA06 and GSA07) in 2000 with recent available data. We applied the temporal dynamic Ecosim module, and tested historical time series of fishing effort, fishing mortality and environmental factors as potential drivers. Observed biomass and landings of key species were used to validate model projections. A spatial-temporal Ecospace model was developed to project species distribution changes. Results showed historical biomass and catch changes driven by a combination of high fishing pressure and environmental change (i.e. increase in temperature and salinity, and decline in primary productivity). Small pelagic fish showed significant temporal changes and predicted shifts in their distributions, following a latitudinal gradient. Predators and competitors showed changes as well, displaying heterogeneous spatial patterns, while fisheries landings declined. Overall, results matched observations (e.g., decline of sardine, fluctuations of anchovy and increases in bluefin tuna) and ill

Citizen science plays a crucial role in helping monitor biodiversity and inform conservation. With the widespread use of smartphones, many people share biodiversity information on social media, but this information is still not widely used in conservation. Focusing on Bangladesh, a tropical megadiverse and mega-populated country, we examined the importance of social media records in conservation decision-making. We collated species distribution records for birds and butterflies from Facebook and Global Biodiversity Information Facility (GBIF), grouped them into GBIF-only and combined GBIF and Facebook data, and investigated the differences in identifying critical conservation areas. Adding Facebook data to GBIF data improved the accuracy of systematic conservation planning assessments by identifying additional important conservation areas in the northwest, southeast, and central parts of Bangladesh, extending priority conservation areas by 4,000–10,000 km2. Community efforts are needed to drive the implementation of the ambitious Kunming–Montreal Global Biodiversity Framework targets, especially in megadiverse tropical countries with a lack of reliable and up-to-date species distribution data. We highlight that conservation planning can be enhanced by including available data gathered from social media platforms

As the effects of climate change increase, distributional range shifts of species are also expected to be magnified, necessitating a better understanding of their social-ecological implications for the adaptive management of fisheries and biodiversity conservation. In this paper, we focused on the human dimensions of recreational fisheries in the context of an ongoing distributional range shift of a target species. Specifically, we mined data on YouTube from recreational anglers and spearfishers targeting the white grouper (Epinephelus aeneus), a species expanding northwards in the northwestern Mediterranean Sea (Italy, France, and Spain). We retrieved 453 videos from Italy and Spain. We analyzed the social engagement of the videos (i.e., number of views, likes, and comments) and applied sentiment analysis to all the comments posted on these videos. Results showed that social engagement is overall higher for spearfishers than anglers. We documented an overall positive polarity and positive emotions in the comments of the posted videos, but specific negative polarity and negative emotions were more common in angling videos than in spearfishing ones. Most importantly, we detected a significant positive correlation between the emotions of joy and surprise and the latitude at which white grouper was caught. This result suggests that recreational fishers may respond to the arrival of the white grouper by showing more joy and surprise at higher latitudes where the species is rare than at lower latitudes where the species is common. Our study illustrates how digital data from social media can be used to monitor social-ecological interactions, such as tracking species distributional range shifts and the human responses to them, with potential management implications. Specifically, these results may be informative to adapt necessary tailored-management actions by improving engagement with fishers and enhancing more effective communication strategies, finally evoking environm

El proyecto GES4SEAS (Archieving Good Environmental Status for maintaining ecosystem services, by assessing integrated impacts of cumulative pressures) es un proyecto europeo, que empezó el año 2022 y terminará en 2026, y tiene como objetivo principal facilitar datos y distintas herramientas para guiar la aplicación de la gobernanza marina con la finalidad de minimizar las presiones humanas y sus impactos sobre la biodiversidad marina y el funcionamiento ecosistémico, al mismo tiempo que se mantiene el proveimiento de los servicios ecosistémicos. [...]

Una de las principales consecuencias del cambio climático es el calentamiento de los océanos (Cheng et al., 2019; Pinsky et al., 2020M; Pörtner y Knust, 2007). Este calentamiento tiene consecuencias profundas para la vida marina y, en consecuencia para las actividades socioeconómicas que dependen de los recursos marinos [...]

El proyecto SEINE-ETP, es un proyecto de colaboración entre científicos, ONGs y pescadores que trata de comprender mejor la evolución de la pesquería de pequeños pelágicos de Castellón, poniendo especial énfases en el análisis de la interacción de la pesquería con especies en peligro, amenazadas y protegidas (ETP). [...]

Small-scale fishing plays a major role in regional economies worldwide and, with a large number of small vessels involved, it provides employment and livelihood to coastal communities. Generally recognized as more selective than other fishing practices, small-scale fishery can nevertheless be subjected to high rates of discards of both non-target species and small-sized individuals, which in turn could lead to both decreased incomes for fishers and increased depletion of fish stocks. However, if the relationship between fish size and price has long been assessed, the effect of enhanced size-selectivity of fishing gears and consequent economic gains has been little investigated. This study, set in the Porto Cesareo Marine Protected Area (Italy, Ionian Sea), aimed at testing effective strategies to improve trammel net selectivity, reducing discards and maximizing the income for fishers. Different mesh sizes (20, 22 and 24 mm) trammel nets were employed. The study consisted in 72 fishing days from July 2012 to September 2013 and each day involved experimental fishing with the three mesh sizes. A total of 16008 specimens (103 species) were collected but the analysis focused on the 18 most common species in the area for a total of 12782 individuals. Mesh size trammel nets of 20 mm and 22 mm yielded most of the biomass, 324.8 and 321.5 kg respectively, while the 24 mm mesh yielded 280.7 kg. The 24 mm mesh, even if accounted for lower income compared to the 22 mm mesh (2383.9 € vs 2590.5 €, respectively), provided significant 50% reduction of discards compared to the 20 and 22 mm mesh. The use of 24 mm mesh size was found to be an effective strategy to reduce the number of discarded organisms and, consequently, the pressure exerted on local fish stocks with associated higher revenue for fishers. The results of this study demonstrated that trammel net selectivity can improve and support conservation measures and concurrently increase profitability of local fishery

The socio-cultural, economic, and environmental conditions of the world are changing rapidly and recreational fisheries will have to adapt to the uncertain future. Key research areas include assessing the sustainability of recreational fishing in response to climate change, ongoing biodiversity decline and changing social values. In this context, technological advances and digitalization can play a major role in advancing recreational fisheries. We evaluated the contributions of research that was presented at the 9th World Recreational Fishing Conference relative to 100 key research questions identified for recreational fisheries in 2020. Given that the 9th WRFC happened in the midst of the COVID-19 pandemic, we additionally synthesise impacts of COVID-19 on recreational fisheries. We found that the majority of contributions focused on resource monitoring and catch and release, while less attention was dedicated to governance, management-stock and habitat enhancement, and threats to sustainability. Rapid technological advances represent both a challenge (e.g., difficulty in management response), but also an opportunity for recreational fisheries (e.g., hyper connectivity of digital platforms for communication). Science is helping recreational fisheries to adapt and remain resilient to rapid social and environmental uncertainties, but this knowledge must be incorporated into governance structures and resource allocation strategies to ensure effective implementation

El mar Mediterráneo contiene entre el 7 y el 10 % de la biodiversidad marina del planeta y sostiene una actividad pesquera importante tanto a nivel social como económico. [...]

La pesquería de cerco española del Mediterráneo se encuentra ante un doble reto ecológico y socioeconómico. [...]

Recreational spearfishing is a fishing method that occurs globally, yet receives considerably less attention in the scientific literature relative to other recreational fishing methods, such as angling. Lack of scientific information on spearfishing may negatively affect the development and management of marine recreational fisheries. We conducted a systematic review of 102 peer-reviewed papers published between 1967 and 2022 pertaining to marine recreational spearfishing. Based on this literature review, we provide an overview of key insights across social, economic, and ecological dimensions of marine recreational spearfishing. While spearfishers represent less than 5% of marine recreational fishers, the participants are younger and may differ from recreational anglers in their motivations, with suggestions of increased well-being generated from a close connection with the sea during underwater fishing. Recreational spearfishers mostly target species of moderate to high levels of vulnerability that are mid to high trophic level carnivores. Though spearfishers can deliberately target larger individuals of exploited populations, this is not a generalizable pattern. Despite a growing body of research on the ecological impacts of marine recreational spearfishing, there is limited knowledge of these effects and their mechanisms across biological levels of organization (e.g., individual, population, community and ecosystem) compared with those of other fishing methods. Recreational spearfishers can contribute to advances in marine ecological knowledge, and inclusive participatory management could represent a key step towards transformative sustainable development of marine recreational spearfishing. Throughout the review, we identify gaps in the research and areas where future research is needed to better inform the socio-economic importance, ecosystem impacts and future management of marine recreational spearfishing

Artisanal fisheries in the Mediterranean are suffering from a decades-long crisis, and urgent interventions are needed to reverse this trend. Despite the increasingly recognized importance of the human dimension of fisheries, socio-economic data on Mediterranean artisanal fisheries are lacking. To address this shortage, this paper offers a socio-economic snapshot of artisanal fisheries operating in the Tuscan Archipelago (GSA 9). Information was collected through semi-structured interviews based on an opportunistic + snowball sampling strategy, with questionnaires reviewed by a panel of 10 experts following the Delphi technique. Information was gathered on fishers, fishing activities, gears, seasonality, catches of alien and thermophilic species, commercial destination of the catch and fishers’ opinions on the main challenges and opportunities in the sector. The results show an artisanal fishing sector facing severe crisis, reduced catches, conflicts with the recreational sector, scarce renewal of both human and technical capital, as well as a general reluctance to explore new business pathways. Yet, many fishers recognized the need for change and showed some early attempts to diversify their sea-related income sources. However, a high discrepancy was observed between the desire and the actual implementation of strategies to strengthen livelihoods and diversify. Efforts are needed to remove the obstacles that prevent the amelioration of artisanal fishers’ businesses and the exploration of new opportunities for managing, protecting and adequately valorizing local marine resources. This goal could be achieved through the establishment of synergies between the fishing and tourism sectors, if the socio-ecological sustainability of artisanal fisheries is sought, both in the Tuscan Archipelago and at other sites

[EN] According to a new ICM-CSIC study, there is a high correlation between data collected through social networks and those collected through traditional monitoring, [ES] Según un nuevo estudio del ICM-CSIC, hay una alta correlación entre los datos recogidos a través de las redes sociales y los recopilados durante los monitoreos tradicionales, [CAT] Segons un nou estudi de l'ICM-CSIC, hi ha una alta correlació entre les dades recollides a través de les xarxes socials i les recopilades durant els mostrejos tradicionals

The socio-cultural, economic, and environmental conditions of the world are changing rapidly and recreational fisheries will have to adapt to the uncertain future. Key research areas include assessing the sustainability of recreational fishing in response to climate change, ongoing biodiversity decline and changing social values. In this context, technological advances and digitalization can play a major role in advancing recreational fisheries. We evaluated the contributions of research that was presented at the 9th World Recreational Fishing Conference relative to 100 key research questions identified for recreational fisheries in 2020. Given that the 9th WRFC happened in the midst of the COVID-19 pandemic, we additionally synthesise impacts of COVID-19 on recreational fisheries. We found that the majority of contributions focused on resource monitoring and catch and release, while less attention was dedicated to governance, management-stock and habitat enhancement, and threats to sustainability. Rapid technological advances represent both a challenge (e.g., difficulty in management response), but also an opportunity for recreational fisheries (e.g., hyper connectivity of digital platforms for communication). Science is helping recreational fisheries to adapt and remain resilient to rapid social and environmental uncertainties, but this knowledge must be incorporated into governance structures and resource allocation strategies to ensure effective implementation.

Behavioral rhythms are a key aspect of species fitness, since optimize ecological activities of animals in response to a constantly changing environment. Cabled observatories enable researchers to collect long-term biological and environmental data in real-time, providing relevant information on coastal fishes’ ecological niches and their temporal regulation (i.e., phenology). In this framework, the platform OBSEA (an EMSO Testing-Site in the NW coastal Mediterranean) was used to monitor the 24-h and seasonal occurrence of an ecologically iconic (i.e., top-predator) coastal fish species, the common dentex (Dentex dentex). By coupling image acquisition with oceanographic and meteorological data collection at a high-frequency (30 min), we compiled 8-years’ time-series of fish counts, showing daytime peaks by waveform analysis. Peaks of occurrence followed the photophase limits as an indication of photoperiodic regulation of behavior. At the same time, we evidenced a seasonal trend of counts variations under the form of significant major and minor increases in August and May, respectively. A progressive multiannual trend of counts increase was also evidenced in agreement with the NW Mediterranean expansion of the species. In GLM and GAM modeling, counts not only showed significant correlation with solar irradiance but also with water temperature and wind speed, providing hints on the species reaction to projected climate change scenarios. Grouping behavior was reported mostly at daytime. Results were discussed assuming a possible link between count patterns and behavioral activity, which may influence video observations at different temporal scales., Postprint (published version)

Size-selective mortality may evolutionarily alter life-history as well as individual behavioral and physiological traits. Moreover, size-selective mortality can affect group behavioral traits, such as shoaling and collective properties (e.g., shoal cohesion), which are relevant for finding food and reducing risk of predation. Here, we present experimental evidence using selection lines of zebrafish (Danio rerio) that were exposed to positive (large-harvested), negative (small-harvested), and random (control) size-selective mortality for five generations, followed by eight generations during which harvesting was halted to remove maternal effects and to study evolutionarily fixed outcomes. We investigated changes in shoal cohesion and turnover in monoamines in zebrafish through ontogeny. To that end, we repeatedly measured inter-individual distance in groups of eight fish and the turnovers of dopamine and serotonin in brains of fish from juvenile to the adult stage at 40-day intervals. We, firstly, found that shoal cohesion was overall consistent through ontogeny at group levels suggesting the presence of collective personality. Secondly, we found a decrease in shoal cohesion through ontogeny in the small-harvested and control lines, while the large-harvested line did not show any ontogenetic change. Thirdly, the selection lines did not differ among each other in shoal cohesion at any ontogenetic stage. Fourthly, dopamine turnover increased through ontogeny in a similar way for all lines while the serotonin turnover decreased in the large-harvested and control lines, but not in the small-harvested line. The large-harvested line also had higher serotonin turnover than controls at specific time periods. In conclusion, intensive size-selective mortality left an evolutionary legacy of asymmetric selection responses in the ontogeny of shoal cohesion and the underlying physiological mechanisms in experimentally harvested zebrafish in the laboratory

Marine recreational spearfishing is practiced by a small proportion of recreational fishers and ecological, social and economic aspects of such activities are poorly understood with respect to recreational angling. The Italian Federation of Sport Fishing and Underwater Activities (FIPSAS) started in 2009 the collection of catch data related to Italian spearfishing tournaments. Here, we provide the first snapshot of this catch data regarding 48 tournaments organized in 29 different Italian localities from 2009 to 2020. We also developed a survey to collect social and economic information that has been administrated to participants to the tournaments. We retrieved 8843 specimens caught by spearfishers, which accounted for 33 species and a total biomass of 5665 kg (mean individual mass ± standard error; 0.64 ± 0.01 kg). The five most frequently species represented 78% of the specimens caught (white seabream, Diplodus sargus 48%; brown wrasse, Labrus merula 12%; brown meagre, Sciaena umbra 9%, green wrasse, Labrus viridis 5%; salema, Sarpa salpa 4%). The overall catch per unit effort for all the tournaments was 0.47 ± 0.01 kg/spearfisher/h, and we showed interesting effects of type of tournaments and type of displacement on it. We also assessed the accuracy of participants to catch fish in accordance to tournaments-specific minimum weight limits. The five most caught species showed that spearfishers committed errors around 50 g below the weight limit. The survey showed that spearfishers participating to tournaments are trophy-fish oriented (i.e., they would rather catch one or two big fish than ten smaller fish), but not particularly catch oriented (i.e., they are just as happy if they do not shoot the fish they see and a fishing trip can be successful even if no fish are caught). Regarding the motives for fishing, they fish for experiencing adventure, excitement and new and different things as well as to be underwater. Participants spent from 2 to 26 days in the tourna

Recreational fisheries are diverse in scale, scope, and participation worldwide, constituting an important ecosystem service of marine and freshwater ecosystems. Management of these socio-ecological systems is challenged by monitoring gaps, stemming from difficulties engaging with participants, biased sampling, and insufficient resources to conduct biological or social surveys of fish and human populations. In the Internet age, online data have great potential to make a meaningful contribution to recreational fisheries research, monitoring, and management. Recreational fishers in some countries increasingly use social and other digital media to share their experiences with followers, with most data freely available to web scrapers that compile databases of text (e.g. tweets, status updates, comments), photos, videos and other media that contain information about spatiotemporal activity, sentiments towards catches/experiences, targeted and bycatch species, effort levels, and more. Although the future of recreational fisheries research, monitoring and management will likely involve more digital scraping, uptake is only just beginning and there are several challenges including tool availability/accessibility, sampling biases, and making findings relevant and usable to practitioners. Despite these challenges, we envision fisheries managers will increasingly turn towards online sources of fisheries data to supplement conventional methods. We challenge scientists to work towards continued method development and validation of various digital fisheries data tools and emphasize how biases from the online behaviour of users may complicate interpretations of these data for fisheries management

Fisheries are among the human activities that are most strongly affected by ongoing climate-related changes in the presence and abundance of fish species across the globe. The ecological and social repercussions of such changes for recreational fisheries are however still poorly understood. Here, we compare selected ecological and social dimensions of both recreational angling and spearfishing targeting the bluefish (Pomatomus saltatrix) in Italy. The bluefish has undergone a northward expansion in the region over the last 20–30 years, during which it reached new areas and increased in abundance. Using digital videos and their associated data published by both recreational anglers and spearfishers on YouTube we characterized ecological and social dimensions using a culturomics approach. Specifically, we focused on harvesting patterns, social engagement and sentiments related to the bluefish. Our study revealed four major results: (1) similar harvesting patterns (i.e., declared mass and seasonal upload patterns) related to videos by both recreational anglers and spearfishers; (2) higher social engagement (i.e., number of views and likes) for videos by recreational anglers than spearfishers; (3) differences in themes of discussion, with anglers being mainly interested in fishing strategy and gears and spearfishers being more interested in fishing actions shown on the videos; (4) positive and negative sentiments of both recreational anglers and spearfishers towards the invasiveness and aggressiveness of the species. The latter represents an interesting trade-off associated with recreational fishing of the bluefish: it is perceived as an invasive species, but it is also a valued target fish because its voracity contributes to the quality of the recreational fishing experience. Our study showcases the value of exploring social media and associated data to better understand the ecological and human dimensions of marine recreational fisheries in relation to distributional

Intensive and size-selective harvesting is an evolutionary driver of life history as well as individual behavioral traits. Yet whether and to what degree harvesting modifies the collective behavior of exploited species are largely unknown. We present a multigeneration harvest selection experiment with zebrafish, Danio rerio, as a model species to understand the effects of size-selective harvesting on shoaling behavior. The experimental system is based on a large-harvested (typical of most wild-capture fisheries targeting larger size classes) and small-harvested (typical of specialized fisheries and gape-limited predators targeting smaller size classes) selection lines. By combining high-resolution tracking of fish behavior with computational agent-based modeling, we show that shoal cohesion changed in the direction expected by a trade-off between individual vigilance and the use of social cues. In particular, we document a decrease of individual vigilance in the small-harvested line, which was linked to an increase in the attention to social cues, favoring more cohesive shoals. Opposing outcomes were found for the large-harvested line, which formed less cohesive shoals. Using the agent-based model, we outline possible consequences of changes in shoaling behavior for both fishing and natural mortality. The changes in shoaling induced by large size-selective harvesting may decrease fishing mortality but increase mortality by natural predators. Our work suggests an insofar overlooked evolutionary mechanism by which size-selective harvesting can affect fishing and natural mortality of exploited fish

Consistent inter-individual differences in daily activity rhythms (i.e., chronotypes) can have ecological consequences in determining access to food resources and avoidance of predators. The most common measure to characterize chronotypes in animals as well as humans is the onset of activity (i.e., early or late chronotypes). However, daily activity rhythms may also differ in the relative amount of activity displayed at particular time periods. Moreover, chronotypes may also be linked to other consistent inter-individual differences in behavior (i.e., personality), such as the propensity to take risks. Here, we used the signal crayfish Pacifastacus leniusculus to test the presence of chronotypes and risk-taking personality traits and a potential behavioral syndrome between these traits. We first exposed crayfish to 5 days of light–darkness to measure daily activity rhythms and then we applied a visual predator-simulating stimulus in 2 different contexts (neutral and food). Our results showed consistent (i.e., across 5 days) inter-individual differences in the relative nocturnal activity displayed in the early and middle, but not in the late part of darkness hours. Moreover, while crayfish displayed inter-individual differences in risk-taking behavior, these were not found to be consistent across 2 contexts. Therefore, we were not able to formally test a behavioral syndrome between these 2 traits. In conclusion, our study provides the first evidence of chronotypes in the relative amount of activity displayed at particular time periods. This could be a valuable information for applied ecological aspects related to the signal crayfish, which is a major invasive species of freshwater ecosystems

Intensive and size-selective harvesting is an evolutionary driver of life-history as well as individual behavioural traits. Yet, whether and to what degree harvesting modifies the collective behaviour and the circadian system of exploited species is largely unknown. I will present a multi-generation harvest selection experiment with zebrafish (Danio rerio) as a model species to understand the effects of size-selective harvesting on shoaling behaviour and the circadian system. The experimental system is based on a large-harvested (typical of most wild capture fisheries targeting larger size classes) and small-harvested (typical of specialized fisheries and gape-limited predators targeting smaller size classes) selection lines. I will first show the effects of size-selective harvesting on fish individual personality traits and possible repercussions in terms of mating behaviour and reproductive isolation. Then, I will document an overlooked evolutionary pathway through which size-selective mortality can affect group risk-taking behaviour and consequently the circadian system of fish both at behavioural and molecular level. Finally, I will present an elegant interdisciplinary approach by combining high resolution tracking with computational agent-based modelling and document a mechanism driving fisheries-induced evolution of collective behaviour and predict possible effects on natural and fishing mortality. Overall, I will provide new evidences on how size-selective harvesting can affect fisheries and trophic dynamics

Behavioral rhythms are a key aspect of species fitness, since optimize ecological activities of animals in response to a constantly changing environment. Cabled observatories enable researchers to collect long-term biological and environmental data in real-time, providing relevant information on coastal fishes’ ecological niches and their temporal regulation (i.e., phenology). In this framework, the platform OBSEA (an EMSO Testing-Site in the NW coastal Mediterranean) was used to monitor the 24-h and seasonal occurrence of an ecologically iconic (i.e., top-predator) coastal fish species, the common dentex (Dentex dentex). By coupling image acquisition with oceanographic and meteorological data collection at a high-frequency (30 min), we compiled 8-years’ time-series of fish counts, showing daytime peaks by waveform analysis. Peaks of occurrence followed the photophase limits as an indication of photoperiodic regulation of behavior. At the same time, we evidenced a seasonal trend of counts variations under the form of significant major and minor increases in August and May, respectively. A progressive multiannual trend of counts increase was also evidenced in agreement with the NW Mediterranean expansion of the species. In GLM and GAM modeling, counts not only showed significant correlation with solar irradiance but also with water temperature and wind speed, providing hints on the species reaction to projected climate change scenarios. Grouping behavior was reported mostly at daytime. Results were discussed assuming a possible link between count patterns and behavioral activity, which may influence video observations at different temporal scales