23 documents found, page 1 of 3
Fully protected marine areas linked to reduced home ranges of fishes
Ohayon, S.; Abecasis, D.; Almeida, P.R.; Alós, J.; Aspillaga, E.; Belo, A.F.; Costa, J.L.; Franco, A.; Lorenzo, M.; Ferguson, A.; Guidetti, P.Home range size is a fundamental trait that can affect the probability of fish being harvested and, at the same time, may be affected by fishing. The relationship between home range size and fishing will impact the effectiveness of fully protected areas (FPAs), as it will influence the number of fish moving into fished areas, affecting both spillover and edge effects. One hypothesis is that individuals within F...
Contrasting movements and residency of two serranids in a small Macaronesian MPA
Afonso, P.; Abecasis, D.; Santos, Ricardo Serrão; Fontes, JorgeProtection inside marine reserves and the desired ‘reserve effect’ depend directly on the home rangeand sedentary behaviour of fishes throughout their lives. Benthic territorial predators are typically seenas major candidates to beneficiaries, but empirical evidence of short-versus long term residency is stillsurprisingly rare. We studied the inter-annual patterns of site fidelity and finer scale movements in t...
Toward adaptive management of coastal MPAs: The influence of different conserva...
Abecasis, D.; Afonso, P.; Erzini, KarimThere is still much discussion on the most appropriate location, size and shape of marine protected areas (MPAs). These three factors were analyzed for a small coastal MPA, the Luiz Saldanha Marine Park (LSMP), for which a very limited amount of local ecological information was available when implemented in 1998. Marxan was used to provide a number of near-optimal solutions considering different levels of prote...
Early reserve effects linked to small home ranges of a commercial fish, Diplodu...
Abecasis, D.; Costa, B. H. E.; Afonso, P.; Gonçalves, E. J.; Erzini, KarimStudies that combine both the ecological responses of marine species and protection measures with movement patterns and habitat use are of major importance in order to better understand the performance of marine protected areas (MPA) and how species respond to their implementation. However, few studies have assessed MPA performance by relating local individual movement patterns and the observed reserve effects....
Changes in movements of white seabream (Diplodus sargus) during the reproductiv...
Abecasis, D.; Afonso, P.; Erzini, KarimIt has been hypothesized, based on anecdotal information and reports, that adult white seabream migrate and aggregate during spawning. Because most of the past telemetric studies on this ecologically and commercially important species were short in duration and did not cover the reproductive season, we set out to use longer-term passive acoustic telemetry to test this hypothesis. We found that white seabream ex...
Ichthyofauna of the Selvagens Islands. Do small coastal areas show high species...
Almada, Frederico; Abecasis, D.; Villegas-Ríos, David; Henriques, Sofia; Pais, Miguel P.; Batista, Marisa; Horta e Costa, Barbara; Martins, JoanaThe Selvagens Islands are located in the northeastern Atlantic between the Canary Islands and Madeira Island. As a result of their small size, remote location and harsh sea conditions only a few studies have been conducted to describe their marine species diversity. We were able to identify 29 new coastal fish species, an increase of 33% in the ichthyofauna described for these islands (n = 88). There is a preva...
Can small MPAs protect local populations of a coastal flatfish, Solea senegalen...
Abecasis, D.; Afonso, P.; Erzini, KarimThe benefits of protection of a small (4.3 km(2)) marine protected area (MPA) for Senegalese sole, Solea senegalensis, were investigated through experimental fishing trials and long-term (up to 293days) passive acoustic telemetry. A total of 106 trammel net sets were carried out between 2007 and 2011. Significant differences in abundance and biomass of sole between bottom types/depths (sandy bottoms between 12 ...
First report of cleaning behaviour in white sea bream (Diplodus sargus)
Abecasis, D.; Abecasis, Ana Rita CostaSeveral studies have reported the existence of ectoparasites in the stomach contents of Diplodus sargus. The cleaning behaviour has, however, never been previously observed for this species. In this short study, we report the first observations of the cleaning behaviour of D. sargus. These observations were in two yachting marinas, located in the Portuguese western coast between the months of April and August. ...
Combining multispecies home range and distribution models aids assessment of MP...
Abecasis, D.; Afonso, P.; Erzini, KarimMarine protected areas (MPAs) are today's most important tools for the spatial management and conservation of marine species. Yet, the true protection that they provide to individual fish is unknown, leading to uncertainty associated with MPA effectiveness. In this study, conducted in a recently established coastal MPA in Portugal, we combined the results of individual home range estimation and population distr...
Herbivores strongly influence algal recruitment in both coral- and algal-domina...
Doropoulos, Christopher; Hyndes, Glenn A.; Abecasis, D.; Vergés, AdrianaCoral reefs can exist as coral- and macroalgae-dominated habitats often separated by only a few hundred metres. While herbivorous fish are known to depress the abundance of algae and help maintain the function of coral-dominated habitats, less is known about their influence in algae-dominated habitats. Here, we quantified herbivorous fish and benthic algal communities over a 6 mo period in coral-dominated (back...