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Simple Summary: We investigated the status and population structure of Percnon gibbesi in three areas of the island of Gran Canaria (Canary Islands, Central-East Atlantic) between July 2020 and December 2021. A total of 999 individuals were captured. Monthly sampling allowed us to establish the reproductive season according to the presence of ovigerous females. The methodology and number of individuals analysed were suitable for establishing the length–weight relationships and the life history parameters via modal progression analysis. The analysis of the catches per unit effort (CPUE) revealed the abundance of Percnon gibbesi in the three areas and seems to not conform with the catch quotas established in the Canary Islands Fisheries Law. Percnon gibbesi is a native crab species characteristic of intertidal and subtidal zones of the Atlantic coast of the European Macaronesian archipelagos (Azores, Madeira, and Canary Islands), and probably also in the neighbouring rocky coasts of northwest Africa. P. gibbesi is considered an invasive alien species in almost all of the Mediterranean, with expanding populations from Spain to Turkey, including Libya; However, its biology and ecology are highly unknown, despite all its range of distribution. In the intertidal zones of Gran Canaria Island, this crab, in the intertidal zones of Gran Canaria Island, shows a carapace length range between 4.1 and 22.7 mm (4.1–22.7 in males and 5.7–22.3 in females), where females showed higher weights and lengths than males on average; However, males predominated in all samples, with a sex ratio of 1:0.57. The L∞ for this crab was estimated to be 27 ± 3 mm (23 ± 4 mm for females and 25 ± 4 mm for males). The growth coefficient (K) was 0.24 year−1, the total mortality (Z) was Z = 1.71 year−1, and the natural mortality (M) was 0.47 year−1. Although females grow faster than males, males are more abundant in the larger length classes. Although the presence of ovigerous females indicated that reproduction takes place twice a year, from March to April and from August to September, the number of cohorts detected by the modal progression analysis showed that reproduction takes place all year. [ABSTRACT FROM AUTHOR]

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Batoids, distributed from shallow to abyssal depths, are considerably vulnerable to anthropogenic threats. Data deficiencies on the distribution patterns of batoids, however, challenge their effective management and conservation. In this study, we took advantage of the particular geological and geomorphological configuration of the Canary Islands, across an east‐to‐west gradient in the eastern Atlantic Ocean, to assess whether patterns in the occurrence and abundance of batoids varied between groups of islands (western, central, and eastern). Data were collected from shallow (<40 m, via underwater visual counts and by a local community science program) and deep waters (60–700 m, via ROV deployments). Eleven species of batoids, assessed by the IUCN Red List of Threatened Species, were registered, including three "Critically Endangered" (Aetomylaeus bovinus, Dipturus batis, and Myliobatis aquila), three "Endangered" (Gymnura altavela, Mobula mobular, and Rostroraja alba), two "Vulnerable" (Dasyatis pastinaca and Raja maderenseis), and two "Data Deficient" (Taeniurops grabata and Torpedo marmorata). Also, a "Least Concern" species (Bathytoshia lata) was observed. Overall, batoids were ~1 to 2 orders of magnitude more abundant in the central and eastern islands, relative to the western islands. This pattern was consistent among the three sources of data and for both shallow and deep waters. This study, therefore, shows differences in the abundance of batoids across an oceanic archipelago, likely related to varying insular shelf area, availability of habitats, and proximity to the nearby continental (African) mass. Large variation in population abundances among islands suggests that "whole" archipelago management strategies are unlikely to provide adequate conservation. Instead, management plans should be adjusted individually per island and complemented with focused research to fill data gaps on the spatial use and movements of these iconic species. [ABSTRACT FROM AUTHOR]

As an increasingly important resource in ecological research, citizen scientists have proven dynamic and cost‐effective in the supply of data for use within habitat suitability models. With predictions critical to the provision of effective conservation measures in cryptic marine species, this study delivers baseline ecological data for the Critically Endangered angelshark (Squatina squatina), exploring: (i) seasonal, sex‐differentiated distributions; (ii) environmental distribution predictors; and (iii) examining bias‐corrected, imperfect citizen science data for use in coastal habitat suitability models with cryptic species.Citizen science presence data, comprising over 60,000 hours of sampling effort, were used alongside carefully selected open‐source predictor variables, with maxent generating seasonal male and female habitat suitability models for angelsharks in the Canary Islands. A biased prior method was used, alongside two model validation measures to ensure reliability.Citizen science data used within maxent suggest that angelshark habitat suitability is low in coastal areas during warmer months, with fewer occurrences despite a negligible change in sampling effort. The prime importance of bathymetry may indicate the importance of depth for reproductive activity and possible diel vertical migration, whereas aspect may act as a proxy for sheltered habitats away from open ocean. Substrate as a predictor of female habitats in spring and summer could imply that soft sediment is sought for birthing areas, assisting in the identification of areas critical to reproductive activity and thus locations that may benefit from spatial protections.Model outputs to inform recovery plan development and ecotourism are identified as plausible safeguards of population recovery, whereas the comparison of biased and bias‐corrected models highlights some variance between methodologies, with bias‐corrected models producing greater areas of habitat suitability. Accordingly, an adaptive framework is provided for the implementation of citizen science data within the modelling of cryptic coastal species distribution. [ABSTRACT FROM AUTHOR]

The article informs on mantelline in the Canary Islands. It mentions the mantelline aggregates in different areas of the islands, forming a carpet on the seabed, in many cases making it impossible to see the sand clearly, and camouflage is their main weapon, since they feed by ambushing their prey. It also mentions about its ecology.

The identification and effective protection of nursery areas is critical for elasmobranch conservation. Research on the angelshark (Squatina squatina) is in its infancy, and is particularly challenging during the early life stages, in part because of their rarity, but also because of their camouflage and cryptic behaviour.Focused research on the identification and protection of juvenile angelshark habitat in their stronghold of the Canary Islands has been identified as a priority action to help safeguard the future of this species.This study combines citizen‐science data, satellite imagery, and focused snorkel surveys to complete a first evaluation of juvenile angelshark habitat in the region, upon which further research can be built.One confirmed nursery area, 13 potential nursery areas, and 21 beaches needing further study were identified in this study, based on the existing nursery area criteria.The results were used to develop eight key recommendations on how local and national governments can better protect juvenile angelsharks in the Canary Islands.Further research is urgently needed to confirm whether other beaches in the archipelago meet the nursery area criteria. [ABSTRACT FROM AUTHOR]

Abralia veranyi and Abraliopsis morisii were the most abundant cephalopods caught during epipelagic and mesopelagic surveys off the Canary Islands and accounted for 26% and 35% of the cephalopod catch, respectively. Diel vertical migration patterns were observed in both species. At night, A. veranyi was recorded at depths as shallow as 38–90 m, whereas Abraliopsis morisii occurred at depths of 98–219 m. As individuals grow in mantle length, their diet changes substantially. Abraliopsis morisii showed ontogenetic shifts at 22.9 mm and 35.3 mm dorsal mantle length (DML), while A. veranyi showed ontogenetic shifts at 20.5 mm and 30.9 mm DML. Prior to the first ontogenic shift, both species fed mainly on copepods and mysids. After this shift they fed on larger prey, such as decapods and fish; the diets of larger individuals also contained cephalopods. [ABSTRACT FROM AUTHOR]

The article focuses on spearfishing and its impact on fishery resources in the Canary Islands. It notes that modern underwater fishing, wearing mask diving and rifle was developed in the Mediterranean, in the decade of 1930. It adds that the realization of the type of fishing, unlike the rest of recreational fishing modalities, demand of great physical capacity by the fisherman, mainly because of the need to dive prolonged apnea and long periods of exposure the water.

The article reports that the Atlantic Society of Oceanographers (SAO), in collaboration with the University of Las Palmas de Gran Canaria and the Canary Islands Government, organized the Oceans Forum 2019. It notes that the Atlantic Society of Oceanographers (SAO) has more than 8 years developing activities in favor of knowledge transfer from centers of research to society and administrations public.

In this study, we used a historical collection of photographs taken by recreational fishers from 1940 to 2014, at the island of Gran Canaria, to show both a significant decrease in the mean total length of Epinephelus marginatus and a concurrent change in the composition of captures. Before 1980, the mean total length of fish caught and photographed was c. 100 cm, while after 2009 this was typically < 40 cm. Before 1980, the predominant captured species was E. marginatus (an apex predator), but currently the majority of catches are of omnivorous species, in particular the parrotfish, Sparisoma cretense and seabreams Diplodus spp. Overall, integration of these results indicates a qualitative and quantitative variation in captures of recreational fishers, probably as a sign of change in ecological balances and the overfished status of many target species. [ABSTRACT FROM AUTHOR]

In this paper we consider what may happen to the marine ecosystem of Gran Canaria Island within the 2030 horizon, if fishing strategies different from those currently in place were implemented and we evaluate the effect of, for example, reduction of recreational–artisanal fishing, limitation of catches (e.g. total allowable catches, TAC), or spatial distribution of fishing sectors. From all scenarios tested, only those that significantly reduce the high effort of the recreational fishing would allow the recovery of the most exploited stocks in the marine ecosystem in the short and medium‐term. Moreover, the best management strategy, in contribution to abundance, was obtained with a scenario that has a spatial partition of exploitation rights between artisanal and recreational fishermen and includes no‐fishing zones (NTZ). This work is a first attempt to use spatial and temporal models to assess the effectiveness of alternative fishery policies in the Canary Islands. [ABSTRACT FROM AUTHOR]

1. Angel sharks are among the most threatened fish worldwide, facing regional and global extinction. In Europe, populations of the three Critically Endangered angel sharks (Squatina aculeata, Squatina oculata and Squatina squatina) have been severely depleted. 2. Taking advantage of the last global 'hotspot' of the angelshark, Squatina squatina, this study gathered data through a citizen science programme to describe the occurrence of this shark in the coastal waters of the Canary Islands. Specifically, this study described (1) the population structure, and (2) habitat use of this species, which was used in a Species Distribution Model to (3) examine realized and potential distribution patterns, and to (4) determine the relative importance of environmental predictors on the occurrence of S. squatina. 3. Over the 12 months sampling period (April 2014 - March 2015), 678 sightings were reported. Individuals ranged from 20 to 200 cm (total length). Larger sightings of both females and neonates occurred mostly in April to July, i.e. during the pupping season. Males were significantly more frequent in November to January, i.e. during the mating season. Angelsharks were encountered at depths from <1 m to a maximum of 45 m. Small-sized individuals (i.e. neonates) exclusively occurred in shallow water (0-25 m). Most sharks occurred on sandy bottoms adjacent to reefs. 4. Even though sightings were recorded at all seven islands in the archipelago, there were fewer encounters in the western than the eastern islands. 5. The Species Distribution Model indicated that the probability of occurrence mainly correlated with sea surface temperature, chlorophyll, salinity and depth. Areas with the greatest habitat suitability were in shallow water. 6. The angelshark displayed spatial (vertical and horizontal) and temporal segregation by size and sex. This information is vital to inform conservation of this Critically Endangered shark in its last stronghold. [ABSTRACT FROM AUTHOR]

The article reports on the acoustic monitoring of the behavior of angel in the Canary Islands. It notes that the conservation of the angel in the Canary Islands has managed to take a new qualitative leap after the completion of the project. It adds that the Canary Islands are today the last stronghold of stable populations of this species, as well as its inclusion in the Spanish Species Catalog.

Angel sharks are among the most threatened species of sharks globally. Twenty-two species have been identified globally so far, with three species being present in the Mediterranean Sea: Squatina aculeata, Squatina oculata, and Squatina squatina. The Mediterranean populations of all three species have been assessed as Critically Endangered by the IUCN Red List of Threatened Species due to the steep decline of their populations as a result of their historical and current overexploitation by demersal fisheries. Therefore, currently there is an ongoing increasing effort for advancing the conservation of the species in the basin. Recently, in the context of the Regional Action Plan for Mediterranean Angel Sharks, the Aegean Sea and Crete have been identified as critical areas for all three species. This study provides the first predictive distribution map of the three angel shark species in the basin, while critical areas for the conservation of the species were identified through a systematic spatial conservation planning analysis. Our analysis revealed low overlapping between the existing MPA network and critical areas for the distribution of the species primarily in Greece and then Turkey, while 20% of the critical areas for the distribution of the species overlaps with Fisheries Restricted Areas of the region. This highlights the need for creating MPAs focusing on shark conservation within the Mediterranean that are currently completely absent. In addition, we provide policy recommendations that can secure better protection of angel sharks through the enforcement of the current legislations and the engagement of all relevant stakeholders. [ABSTRACT FROM AUTHOR]

Analysis of 322 cuttlebones of Sepia bertheloti caught in the waters of the Northwest Africa showed significant differences in growth between males and females. Morphometric analysis revealed a relatively different cuttlebone growth pattern between sexes, with males presenting faster growth in length to reach larger sizes and females displaying greater growth in width. This difference in cuttlebone growth is related to female gonadal development and the subsequent increase of the paleal cavity, providing more support and space to accommodate a higher number of oocytes. [ABSTRACT FROM AUTHOR]