Pinna nobilis is a sensitive and vulnerable species and is hence considered a good indicator of anthropogenic pressures on marine ecosystems. This study provides novel data on the density and distribution of endangered P. nobilis on the Turkish coasts. Threats to the status of P. nobilis, including by‐catch and illegal collection, were assessed, as was the general awareness of people about the endangered status of fan mussels. The data sources consisted of direct observations from diving surveys and the local ecological knowledge (LEK) of fishers and scuba‐divers. Results demonstrated that the density of P. nobilis significantly changed with environmental parameters, such as depth, and among different sampling areas. The number of damaged individuals was lowest in the areas that were distant from human influences such as ports and tourist beaches. The density estimations of P. nobilis across a wide geographic area around the Turkish coasts revealed that the density of fan mussels was highest around western coasts in comparison with southern coasts. Fishers and divers indicated that the population of this species has decreased during the last decade. The main causes of this decline were suggested to be the impacts of fishing gear, poaching, pollution, and boat anchoring. The highest volume of by‐catch was estimated to be taken by trawls. In general, the knowledge and local awareness of the conservation importance and status of fan mussels was poor. The study has identified those areas where fan mussels occur at a high density, and hence may indicate areas for possible conservation protection status. Second, areas exposed to the illegal harvesting of fan mussels were highlighted. Societal concern would benefit from educational activities to raise awareness of the ecological importance and conservation needs for fan mussels in Turkey.

The fan mussel, or noble pen shell, Pinna nobilis Linnaeus, 1758 is an endemic species to the Mediterranean belonging to the Pinnidae family (Vázquez-Luis et al., 2017). The species is known as the largest bivalve for this region (Katsanevakis, 2006). Pinna nobilis lives at depths ranging from 0.5 to 80 m (Öndes, Kaiser, & Güçlüsoy, 2020). The habitats of P. nobilis include algae and phanerogam facies, muddy and sandy substrates (Katsanevakis, 2006; Prado, Caiola, & Ibáñez, 2014). Differences were found in the population density of P. nobilis among habitats, depth and ecoregions (Basso et al., 2015). This species plays key ecological roles including providing a habitat for many species, reducing turbidity and filtering water (Katsanevakis et al.

In this study, the relative growth, size-weight relationships and size at onset of maturity of the brown crab Cancer pagurus were investigated in the Isle of Man. For the analyses of relative growth and size at onset of maturity, the samples were collected seasonally between autumn 2012 and spring 2013 using several methods: pot surveys, dredge and trawl surveys, market surveys and shore surveys. Results showed that allometric growth occurred in the chelipeds of males (n = 87) and in the abdomen of females (n = 222). Four different measures of maturity (behavioural, functional, morphometrical and physiological) were examined. With respect to the behavioural maturity, the smallest female crab found with a sperm plug measured 110 mm CW, whereas in terms of functional maturity the smallest ovigerous female had a CW of 134 mm. Based on direct observations of gonad maturity, 50% of females were mature at 108 mm CW, whereas 50% of males were mature at 89 mm CW. The size at the onset of maturity measurements of female and male C. pagurus based on gonad development is smaller than the current minimum landing size (130 mm), and therefore this suggests that the current minimum landing size is an adequate management measure.

Brown crab contributes to small-scale fisheries in the Isle of Man and landings (495 t) were worth in excess of £0.5 million in 2012. The present study sought to fill evidence gaps needed to improve the scientific understanding of this fishery. Observer data were collected to examine the spatial and temporal variations in the size distribution and sex ratio of crabs around the Isle of Man. This study also aimed to evaluate the catch characteristics of brown crab using logbook data (2007–2012), observer data (2012–2013) and questionnaire survey data (2013). The sex ratio is highly variable in different areas across seasons and was perhaps indicative of migration patterns in relation to mating. This change was most notable with a strong increase in the proportion of females to the south and west of the Isle of Man in the autumn months. The depth and pot volume were important factors that influenced the catch per unit effort (CPUE). Future survey designs would need to ensure adequate spatial coverage of the east and west coast of the Isle of Man together with a seasonal sampling regime that captures the spatial change in the distribution and abundance of male and female crabs.

Baited trap or pot fisheries are considered to have relatively few wider ecosystem effects on the marine environment, particularly when compared with towed mobile fishing gear. However, this assumption is rarely tested in the field. This study aimed to determine the composition of non-target species that occur in crustacean pots and to assess spatial and temporal differences in catches in the waters around the Isle of Man, Irish Sea. The data were collected using fishery independent surveys and a questionnaire study. Based on fishery independent surveys, a total of five taxonomic groups and 43 species occurred as by-catch. The dominant by-catch species was velvet crab Necora puber. The by-catch per unit effort (BPUE) for all of the non-target species was low particularly in comparison to towed bottom gear fisheries around the Isle of Man. BPUE of species composition varied considerably between different locations around the Isle of Man. The results of both the fishery independent and questionnaire data suggested that the by-catch rates varied with season with peak BPUE occurring in spring which then declined into autumn and winter. By-catch composition did not decrease significantly with an increasing target species catch. Overall, by-catch was low relative to target species catch which may be partially attributable to the use of escape panels in pot fisheries in the Isle of Man.

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Background. The socio-economic characteristics of small-scale fisheries have rarely been documented in the eastern Mediterranean. This study aimed to determine the current socio-demographic status, historical changes in demography and fishing activity, fishing expenditures, and the main problems of small-scale fisheries in the Aegean Sea. Material and methods. Data were collected in 2018, using face-to-face questionnaires from small-scale fishers (n = 190) representing three sub-regions (northern, central, and southern Aegean Sea). The questionnaire included information regarding the main characteristics of fishing vessels, demographic characteristics of fishers, expenditures involved, and other important issues. Furthermore, some demographic characteristics (e.g., age and marriage status) and fishery-specific characteristics (e.g., active fisher ratio) observed in our study, were compared to the published data, to reveal if any changes have prevailed historically. Results. The mean age of fishers was 50 ± 10 years, and many of them were married males with primary school education. The highest two fisheries expenditures were fuel and oil expenses and personnel (crew) expenses. The fisheries expenditures did not show a statistically significant difference in terms of geographical location. However, there was a significant difference in the total fisheries expenditures depending on fishery type; fishers who use an encircling net reported higher expenditures, in comparison to other fishing types. The results showed that the active fisher ratio and the ratio of fishers who do not have other income has decreased significantly over the last 10 years. In addition, engine power (kW) showed a significant increase over the last 15-16 years. The main problems identified were insufficient inspection, illegal fisheries, and a decrease in stocks. Conclusions. Increased fishing expenditures and decreasing fish stocks in the Aegean Sea resulted in a decrease in the number of active fishers. Therefore, many fishers tended to have additional jobs, and some of them considered leaving fishing. To maintain the sustainable management of the small-scale fisheries in Turkey, we suggested that the catch and fishing effort should be monitored using the mandatory logbooks, and the hook number should be standardized.