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Fish movements are fundamental to their ecology and survival. Understanding the causes and consequences of the spatial behaviour of fish is of high relevance as it provides critical knowledge for conservation purposes. Skate (Rajidae) populations face an unprecedented global decline due to overfishing. In this study, we used acoustic telemetry to track the movements of nine individuals of the near threatened thornback skate (Raja clavata) around the Cíes Islands, a small marine protected area in the northwest of the Iberian Peninsula. Our results demonstrate the significant impacts of biotic and abiotic drivers on the spatial behaviour of R. clavata. Overall residency inside the study array was low (0.073), differed between sexes (higher for females) and over the course of the year (peaking in summer). The analysis of the direction of the excursions performed by R. clavata individuals revealed high consistency in the exit and entry areas and a strong connectivity with inshore waters connecting with the Ría de Vigo, as compared with offshore waters connecting with the open ocean. Finally, the activity space of R. clavata also varied over the time of the year with a peak in summer. This study provides an important baseline information for understanding the spatial behaviour of R. clavata that can serve as a starting point for planning future conservation actions or studies.

Shark populations have suffered dramatic declines across the world as a result of overfishing.Marine protected areas (MPAs) can help restore overfished populations; however, their effectiveness largely relies on understanding the ecology of the targeted species.This study investigated the spatial ecology of the intensely harvested but understudied small spotted catshark (Scyliorhinus canicula) through acoustic telemetry in the Cíes Islands, a small MPA in the north‐west of the Iberian Peninsula.There were significant effects of diel, seasonal cycles, biotic (sex and total length) and abiotic (bottom sea temperature) variables on the spatial behaviour of S. canicula. The mean residency index was low (0.27) and movement patterns suggested a strong connection with inshore waters. While the probability of presence in the study area was mainly driven by sex (i.e. greater for females), a drastic increase in activity was observed at night (compared with daytime hours). The activity space decreased with larger body sizes. Warmer waters were related to higher activity levels and larger activity spaces.This study provides essential knowledge of the spatial behaviour of S. canicula, with significant implications for the conservation and management of this species. The results indicate that small MPAs may fail to protect the whole range of movements of S. canicula, but suggest a larger protection potential for females.To be effective for S. canicula conservation, MPAs should be appropriately sized and designed for the ranging behaviour of the target species in order to provide total protection. Temporal restrictions on fishing at night mirroring the peak activity pattern of S. canicula could be implemented to limit the probability of its capture. [ABSTRACT FROM AUTHOR]

Knowledge of the spatial behaviour of aquatic living resources is essential to assess their vulnerability to environmental and anthropogenic stressors and inform efficient management strategies.Elasmobranchs are particularly vulnerable to exploitation. Within this group of fish, the implementation of species‐specific conservation actions has been challenging due to insufficient information on their biology and ecology.In this study, acoustic telemetry was used to investigate the seasonal variation, diel patterns, and biological and sea temperature effects on the spatial behaviour of the endangered undulate skate, Raja undulata, within a marine protected area in north‐west Spain.Movement and behaviour were mainly driven by diel and seasonal patterns. The presence of the tagged skates in the study area peaked during summer. Space use was highest in late spring and activity was lowest during summer. Skates used more space and were more active during night‐time as compared to daytime, when they stayed in sandy bottoms. Sea temperature had a negligible positive effect on activity.Our work represents an important contribution to the understanding of the ecology of this endangered, yet commercially important skate in Europe, and provides important insights for the implementation of spatial and temporal restrictions aimed at reducing mortality and bycatch of this species. [ABSTRACT FROM AUTHOR]

Individual acoustic tracking is a valuable tool to understand the behavioral ecology of aquatic species and to inform conservation actions. In this study, we examined the spatial behavior of single individuals of four common coastal fish species (striped red mullet, Mullus surmuletus;corkwing wrasse, Symphodus melops;pollack Pollachius pollachius;and white seabream, Diplodus sargus) in the National Park "Illas Atlánticas de Galicia" (NW Spain). The use of space of these species varied between 237,975 m2 and 48,725 m2, and the number of days that each fish was detected in the study area ranged between 35 and 110 days with weighted residence index ranged between 0.02 and 0.43. Pollackleft the array after 235 days, and was recaptured 342 days after tagging ~10 km south from the study area. The movement of the studied species followed contrasting diel patterns. While white seabream and striped red mullet moved over larger areas during the day, pollackranged over larger areas during the night. This single individual study ('Solo datasets') represents a useful baseline for future research projects by providing preliminary knowledge of these poorly known species in the study area. [ABSTRACT FROM AUTHOR]

Discard reduction is a cornerstone of the European Common Fisheries Policy. The discard ban policy, which aims to reduce fisheries discards, is particularly challenging for small-scale fisheries. Demonstrating high survival rates of discarded individuals may provide flexibility to the application of the discard ban through the so-called survival exemption. Here we used acoustic telemetry and mark-recapture data to estimate discard survival of coastal elasmobranch species at multiple temporal scales. We focused on four species targeted by the small-scale fishery in Galicia (NW Spain), one of the most important fishing regions in Europe: Scyliorhinus canicula , Raja undulata , R aja clavata and R aja brachyura. The overall survival rate was 90% on the short term and 85.7% on the long term, but it varied among species. Survival rates of R. clavata and S. canicula on the short term were 70% and 100%, respectively, and 66.7% and 92.9% on the long term, respectively. All the individuals of R. brachyura and R. undulata survived on the long term. Our results are critical to support the application of survival exemption in small scale fisheries. [Display omitted] • The EU discard ban policy is challenging for the small-scale fishing fleet. • The survival exemption provides flexibility to the application of the discard ban. • Survival of coastal elasmobranchs in NW Spain was estimated using acoustic telemetry. • The survival rate ranged from 66 to 100%. [ABSTRACT FROM AUTHOR]

Effective fisheries management needs to consider spatial behavior in addition to more traditional aspects of population dynamics. Acoustic telemetry has been extensively used to provide information on fish movements over different temporal and spatial scales. Here, we used a fixed-receiver array to examine the movement patterns of Labrus bergylta Ascanius 1767, a species highly targeted by the artisanal fleet of Galicia, NW Spain. Data from 25 individuals was assessed for a period of 71days between September and November 2011 in the Galician Atlantic Islands Maritime-Terrestrial National Park. Fish were present within the monitored area more than 92% of the monitored time. The estimated size of individual home ranges, i.e. the area where fish spent most of their time, was small. The total minimum convex polygons area based on all the estimated positions was 0.133±0.072km2, whereas the home range size estimated using a 95% kernel distribution of the estimated positions was 0.091±0.031km2. The core area (50% kernel) was 0.019±0.006km2. L. bergylta exhibited different patterns of movement in the day versus the night, with 92% of the fish detected more frequently and traveling longer distances during the daytime. In addition, 76% of the fish displayed a larger home range during the day versus during the night. The linearity index was less than 0.005 for all fish suggesting random movements but within a relatively small area, and the volume of intersection index between consecutive daily home ranges was 0.75±0.13, suggesting high site fidelity. The small home range and the sedentary behavior of L. bergylta highlight the potential use of small MPAs as a management tool to ensure a sustainable fishery for this important species. [ABSTRACT FROM AUTHOR]