14 documents found, page 1 of 2

ESTADO DOS STOCKS EM 2020 E ACONSELHAMENTO CIENTÍFICO PARA A SUA GESTÃO EM 2021

This report presents the stock assessment results for the species exploited by Portugal in 2020 and the scientific advice for their management in 2021. For each resource the stock distribution area, the source for the scientific advice, the biological reference points, the state of exploitation and scientific advice and the management measures.; O presente relatório apresenta os resultados das avaliações do est...

Assessment of habitat suitability for common cockles in the Ria the Aveiro Lago...

The common cockle Cerastoderma edule is a widespread bivalve species inhabiting estuarine systems across the North East Atlantic, where it provides several ecosystem services, and represents a valuable fishery resource for local economies. However, anthropogenic pressure and more frequent extreme weather events threaten the resilience of the species. Spatially explicit information on species distribution is cri...

Biology of the common cockle Cerastoderma edule (Linnaeus, 1758) in Ria de Avei...

This study reports the reproductive cycle, condition index, size at first maturity, growth and the morphometric relationships of the common cockle Cerastoderma edule in Ria de Aveiro (NW Portugal), fundamental knowledge in fisheries management planning and ecosystem conservation. The reproductive cycle was monitored for a period of two years, from January 2013 to December 2014. Spawning extended from June to Oc...

Reproductive cycle of the Manila clam (Ruditapes philippinarum): an intensively...

The present study aimed to describe the reproductive cycle and estimate the size at sexual maturity of the Manila clam (Ruditapes philippinarum) in the Tagus Estuary (Portugal). Specimens were collected monthly from September 2013 to December 2015 during fishing surveys using bivalve dredges. The gametogenic cycle was described in detail using gonad histology and monitored throughout the study period by the mon...

Meat yield of Bolinus brandaris (Gastropoda: Muricidae): comparative assessment...

The present study assessed the influence of sex, size and reproductive status on the meat yield (soft tissues proportion) of the purple dye murex (Bolinus brandaris) from the Ria Formosa lagoon (southern Portugal). During one year of monthly sampling (October 2008-September 2009), average meat yield of B. brandaris was 40.5 +/- 6.1% (range: 25.8-56.1% wet weight), with no significant differences between sexes. ...

Geographical variation in shell shape of the pod razor shell Ensis siliqua (Biv...

Age and growth in three populations of Dosinia exoleta (Bivalvia: Veneridae) fr...

The present study aimed at estimating the age and growth in three populations of Dosinia exoleta from the Portuguese coast (Aveiro in the north, Setúbal in the southwest and Faro in the south). Two techniques were compared to ascertain the most suitable method for ageing D. exoleta. Growth marks on the shell surface and acetate peel replicas of sectioned shells were the techniques applied. Two hypotheses were t...

Geographical variation in shell shape of the pod razor shell Ensis siliqua (Biv...

The present study assessed the existence of variation in the shell shape of the pod razor shell (Ensis siliqua) throughout its distributional range in the north- eastern Atlantic. Shells of E. siliqua caught at seven collecting sites (three in Portugal, three in Spain and one in Ireland) were studied by geometric morphometric methods, using both landmark- and contour-based methods. Both approaches (landmarks in...

Environmental quality assessment combining sediment metal levels, biomarkers an...

Macroinvertebrate benthic communities are one of the key biological components considered for the assessment of benthic integrity in the context of the Water Framework Directive (WFD). However, under moderate contamination scenarios, the assessment of macrobenthic alterations at community level alone could be insufficient to discriminate the environmental quality of coastal and transitional waters. Keeping this...

Reproductive cycle of Bolinus brandaris (Gastropoda: Muricidae) in the Ria Form...

The purple dye murex Bolinus brandaris is a commercially valuable gastropod in Portugal. However, there is a lack of knowledge on the reproductive cycle in Atlantic populations of this species. In this context, the reproductive cycle of B. brandaris from the Ria Formosa lagoon, southern Portugal, was studied using standard histology and light microscopy and the calculation of bio-physiological indices (gonadoso...