Loading...
2 results
Search Results
Now showing 1 - 2 of 2
- Reproductive traits of the African mud crab (Panopeus africanus) on the South Portuguese coastPublication . N. Monteiro, J.; Ovelheiro, Andreia; Pinto, Miguel; Teodosio, Maria; Leitão, FranciscoSpecies with high economic relevance are widely studied in contrast with low economic relevance species such as Panopeus africanus, a small crab with a wide distribution along the eastern Atlantic coast, which remains poorly studied in regarding to the biological and ecological issues. Knowledge of reproductive patterns is essential to understand populations dynamics and species biological life-cycle traits. The main objective of the present research was to study the reproductive patterns of P. africanus. The population size structure, maturation stages and gametogenic development aspect, size at maturation, reproductive periods and morphometric-fecundity relationships of P. africanus in the southern Portuguese coast (Ria Formosa) was analysed. Crabs were sampled monthly, from January 2019 to December 2021, with traps and hand collected. The crab's carapace width (CW) ranged between 7 to 52 mm, and it was observed that in smaller and larger CW size classes, the proportion of males was higher, however in intermediate CW size classes the sex ratio was near 1:1. The gonads development was characterized based on histological analysis. Males presented four maturity developmental stages where two stages were immature and two were mature. Females presented six maturity developmental stages, where two stages were immature, and four stages were mature. Regardless of sex, the mean maturity size was 20 mm CW. A high percentage of mature individuals was observed throughout the year however, in the colder months the percentage of mature individuals was lower. Additionally, ovigerous females were only observed in the warmer months, pointing to a short breeding period occurring in the warmer months. Fecundity ranged between 12368 and 84140 eggs/female, following a positive correlation between CW/egg number. These novel results allowed to shed light on reproductive patterns of P. africanus population inhabiting the southern Portuguese coast, contributing also to a better understanding of the basic reproductive biology of this crab populations.
- Eco-socio-economic vulnerability assessment of Portuguese fisheries to climate changePublication . Pinto, Miguel; Albo-Puigserver, Maria; Bueno-Pardo, Juan; N. Monteiro, J.; Teodosio, Maria; Leitão, FranciscoUnderstanding ecological, and socio-economical vulnerabilities is fundamental towards developing and implementing regional adaptation strategies to climate change. The Portuguese coast is situated in a transition zone between temperate ecosystems to the north, and subtropical with Mediterranean characteristics, to the south, with distinct oceanographic regions (north, centre, and south), fish assemblages and socioeconomic realities of fish communities across these regions. We develop a framework to assess fisheries climate vulnerability in each port. A total of 32 ecological and socio-economic indicators were used to measure exposure, sensitivity, and adaptive capacity of the fishing sector to climate change by combining i) environmental projections ii) information from fishing communities (surveys at ports) and iii) landings and socio-economic data from official statistics offices. The vulnerability to climate change across regions, and its expected impact on fishing fleets and local communities, was low-moderate. Such information will enable fishing communities and decision makers to respond to expected climate change effects and direct/indirect associated activities. This framework comprises background information for developing mandatory EU climate adaptation plans that aim to improve the resilience of fisheries socio-economic systems.