Luis Bentes

Universidade do Algarve | UALG · Centro de Ciências do Mar (CCMAR)

The use of tracking devices, such as vessel monitoring systems or automatic identification system, enabled us to expand our knowledge on the distribution and quantification of fishing activities. However, methods and models based on vessel tracking data are mostly devised to be applied to towed gears, whereas applications to multi-gear and passive...

Studies assessing fish spatial behaviour are essential to better understand the performance of marine protected areas. However, few studies have focused on the fine-scale movements related to reproduction, a key feature in a population’s perpetuation. Knowledge of movements modulated by reproduction is particularly important since migrations toward...

This study is the first to evaluate the fish provisioning services of a whole transitional landscape (Ria Formosa lagoon, Portugal), in parallel with the enhancement of growth, survival and production of single cohorts of the most important commercial fish species by vegetated and unvegetated sub-tidal habitats. Based on monthly beach seine samples...

Marine Protected Areas (MPAs) are a tool to safeguard marine natural systems, yet their effectiveness depends on how well they are integrated into the existing socioeconomic context. Stakeholder engagement in MPA design can contribute to increasing integration. This study focuses on the co-design of an MPA between researchers, public administration...

Monitoring the ecological status of marine coastal lagoons requires the integration of multiple indices. However, the efficacy of monitoring programs is complicated by the diverse array of habitats that conform coastal lagoons. In this study, we compared four sampling methods (25-m and 50-m beach seines, beam trawl and Riley push net) in the Ria Fo...

Marine protected areas (MPAs), and specially no-take areas (NTAs), play an important role in protecting target populations from fisheries. When developing spatial conservation and management tools, the design has mainly focused on population-level measures of fish home ranges, spawning and feeding areas, and migration routes. Intraspecific differen...

No-take areas are key instruments to promote the effectiveness of Marine Protected Areas (MPAs), particularly concerning the protection of endangered species such as the dusky grouper (Epinephelus marginatus). However, despite the establishment of no-take areas and the prohibition of catching this species in a southwestern Portuguese MPA (SACVMP—‘S...

Marine Protected Areas (MPAs) have played an important role in the protection of endangered species such as the dusky grouper (Epinephelus marginatus), and the no-take areas have been particularly crucial for this purpose. Yet, despite the establishment of no-take areas and the legislation banning dusky groupers’ catches since 2011 in a southwester...

The first major step in training an object detection model to different classes from the available datasets is the gathering of meaningful and properly annotated data. This recurring task will determine the length of any project, and, more importantly, the quality of the resulting models. This obstacle is amplified when the data available for the n...

Marine Protected Areas (MPAs) require effective indicators to assess their performance, in compliance with the goals of relevant national and international commitments. Achieving and prioritizing shortlists of multidisciplinary indicators demands a significant effort from specialists to depict the multiple conservation and socioeconomic interests,...

EUSeaMap 2021 is the fifth iteration of EUSeaMap. All versions have been produced as part of the EMODnet Seabed Habitats project, which is one of several thematic lots in EMODnet. The project has brought together a European consortium of specialists in benthic ecology and seabed habitat mapping. The partners first collaborated in EMODnet phase 1 (2...

Identifying vulnerable marine habitats is fundamental to promote evidence-based management and a sustainable use of our oceans. Although progress in the mapping of marine benthic habitats has been made, complex ecosystems such as submarine canyons remain largely unexplored, hampering evidence-based management from taking place in these ubiquitous f...

Final report/relatório final do Projeto iNOVPESCA - Redução de capturas acidentais de espécies marinhas protegidas em pescarias costeiras algarvias: inovação de procedimentos e técnicas de mitigação. Contextualização, metodologia, resultados e proposta de boas práticas para encontrar reduzir conflitos entre pescas e espécies marinhas protegidas na...

The recent establishment of the “landing obligation” under the reformed EU Common Fishery Policy has the twofold objective of reducing the excessive practice of discarding unwanted catch at sea and encouraging more selective and sustainable fisheries. Within this context, the awareness of the spatial distribution of potential unwanted catches is im...

Since its inception, in 2009, EMODnet Seabed Habitats has brought together a European consortium of specialists in benthic ecology and seabed habitat mapping to develop a transnational broad-scale seabed habitat map, named EUSeaMap. EUSeaMap is the only pan-European cartographic product that provides a standardised trans-boundary overview of the sp...

Discards is an important issue in fisheries around the world. The spatial management of discards has attracted interest as a potential tool for minimizing the unwanted catch. The aim of the present work was to identify areas with high quantities of bottom trawl discarded catch regarding species subjected to MCRS, in six areas of southern European w...

EUSeaMap 2019 is the third iteration of EUSeaMap. All versions have been produced as part of the EMODnet Seabed Habitats project, which is one of several thematic lots in EMODnet. In the new version, the spatial coverage has been extended further North in order to include the Barents Sea. The spatial detail has substantially been improved. This has...

Reducing the impact on vulnerable species through changes in fishing practices, such as the spatial or temporal avoidance of certain areas, is key to increase the ecological sustainability of fisheries. However, it is often hampered by the availability of sufficiently detailed data and robust indicators. Existing trawl surveys are a cost-effective...

This paper presents the results of a pilot experiment with an existing tidal energy converter (TEC), Evopod 1 kW floatable prototype, in a real test case scenario (Faro Channel, Ria Formosa, Portugal). A baseline marine geophysical, hydrodynamic and ecological study based on the experience collected on the test site is presented. The collected data...

The growth in tourism in the Cape Verdean Sal Island has been a cause as well as a consequence of a number of investments (both by the State and the private entities) to create synergies for that sector, ensuring and promoting the island’s touristic attractiveness. Such increases in the number of visitors, allied with the island’s marine biodiversi...

The European Union Regulation 1380/2013 revising the Common Fisheries Policy (CFP) aims at addressing the by-catch and discarding problem in commercial fisheries by implementing the "Landing Obligation" of the regulated species by 2019. To date, in adjacent waters of the Mediterranean sea, the Gulf of Cadiz (GoC) landing ports are not ready to comp...

Recreational fishing is an important socioeconomic activity that needs systematic studies and data monitoring programs. The Pescardata project, coordinated by the Centre for Marine Sciences of the University of Algarve has two goals: (1) fill the gaps with regard the systematic collection of data on the recreational catches of the species included...

Experimental fishing was conducted off the port of Quarteira (southern Portugal) from October 2016 to February 2017 using standard trammel nets and modified nets rigged with a guarding net. The commercial catches of trammel nets rigged with a guarding net were 46.1% and 38.0% less than those of the standard net in numbers and economic value. Howeve...

This paper presents the results of a pilot experiment with an existing tidal energy converter (TEC), Evopod 1 kW floatable prototype, in a real test case scenario (Faro Channel, Ria Formosa, Portugal). A baseline marine geophysical, hydrodynamic and ecological study based on the experience collected on the test site is presented. The collected data...

The effects of two different slipping methods on the survival, physical and physiological response of sardines, Sardina pilchardus, captured in a purse-seine fishery were investigated in southern Portugal. Sardines were collected and transferred into holding tanks onboard a commercial fishing vessel after being captured, crowded and deliberately re...

Survival estimates for sardine using Kaplan-Meier survival curves (dashed line), overlaid with the predictions from the selected mixture-distribution survival model M3 (solid lines with 95% confidence bands) for the three treatment replicates (1–3): Control, standard slipping (SS) and modified slipping (MS). (TIF)

The estimated impact of the EU Landing Obligation was investigated, which bans discards of regulated species, in South European fisheries through stakeholders' perceptions with the intention to identify implementation shortcomings and practicalities that might lead to obstacles to enforcement. Structured interviews were conducted with 173 fishers i...

The increased number of human activities within the marine environment and the demand for maritime space has increased to a point where in some parts of the globe the demand for maritime space has exceeded the available area. The overlapping objectives and activities have caused severe conflicts among users and with the natural marine environment i...

International Meeting on Marine Research 2016

This paper shares the experiences, observations and discussions that occurred during the completing of an ecosystem services' (ES) indicator framework to be used at European Union and Member States' level. The experience base was drawn from three European research projects and 14 associated case study sites that include 13 transitional-water bodies...

The present study aims to assess if small MPAs can be effective tools to protect thornback rays and enhance their recovery from fishing pressure. For this, a small MPA in Atlantic temperate waters was chosen as a case study. Study questions: - Is this species abundance increasing within the MPA boundaries? - Does this species have high or low site...

Príncipe Island (140 km2) has an incredible rich biodiversity. This region, together with the other Gulf of Guinea islands, was considered one of the 10 Richest Centers of Marine Endemism. The beaches are mainly used by green sea turtles ( Chelonia mydas ) and a small number of hawksbills ( Eretmochelys imbricata ) and leatherbacks ( Dermochelys co...

Príncipe Island (140km2) has an incredible rich biodiversity. This region, together with the other Gulf of Guinea islands, was considered one of the 10 Richest Centers of Marine Endemism. The beaches are mainly used by green sea turtles ( Chelonia mydas ) and a small number of hawksbills ( Eretmochelys imbricata ) and leatherbacks ( Dermochelys cor...

This Good Practice Guide is the outcome of a project co-funded by the European Commission (DG Mare) called Transboundary Planning in the European Atlantic (TPEA), which ran from December 2012 to May 2014. The aim of the project was to demonstrate approaches to transboundary maritime spatial planning (MSP) in the European Atlantic region. This is on...

If marine management policies and actions are to achieve long-term sustainable use and management of the marine environment and its resources, they need to be informed by data giving the spatial distribution of seafloor habitats over large areas. Broad-scale seafloor habitat mapping is an approach which has the benefit of producing maps covering la...

In this study, the length-weight (LWR) parameters were estimated for six syngnathid species, including 2 seahorses and 4 pipefishes, from Ria Formosa, a temperate lagoon from the south coast of Portugal. A total of 5070 fishes were used to determine the LWR. The estimated b value ranged from 2.95 (Nerophis ophidion) to 3.36 (Syngnathus abaster). To...

The main purpose of this work is to produce small scale predictions of Coral garden habitats based on remote operated vehicle (ROV) observations.

The weight-length relationships (WLR) were estimated for five fish species of Ria Formosa, a coastal lagoon in southern Portugal. WLRs for Gobius couchi, Pomatoschistus microps and Parablennius pilicornis were determined for the first time ever and for Gobius cruentatus for the first time for the southern European Atlantic coast.

Artificial reefs are used as management tools for coastal fisheries and ecosystems and the knowledge of habitat use and fish movements around them is necessary to understand their performance and improve their design and location. In this study wild specimens of Diplodus sargus were tagged with acoustic tags and their movements were tracked using p...

This report provides full documentation of the new proposals for EUNIS habitats up to level 5 for marine habitats found under the MeshAtlantic project. Three case studies were presented in detail, the Algarve region and the Southwestern Coast in Portugal and the Basque Country in Spain, plus other contributions from Brittany (France). Overall, ther...

Twenty-five specimens of the hermit crab Calcinus tubularis were observed during SCUBA dives for fauna and flora assessment in the shallow rocky reefs of the southern coast of Portugal between 2003 and 2008. Of the specimens observed, only one specimen used a tube gallery, while the others occupied unidentified gastropod shells with strong bio-cove...

This paper proposes advanced methodologies for the study of tagged marine animals, resorting to telemetry techniques. The robotic tools to be developed and operated will be able to track the acoustic signals emitted by the animals, based on range and depth data acquired with ultra-short baseline positioning (USBL) systems aided Inertial Navigation...

Parallel fishing trials with 0.30 mm diameter monofilament gill nets and longlines using small hooks were carried out in the Algarve (southern Portugal) over a one-year period, 1997-1998, with the objective of comparing species composition, catch rates, discards and size ranges. Four hook sizes of MUSTAD brand, round bent, flatted sea hooks (number...

Ocinebrina nicolai Monterosato, 1884 a marine mollusc belonging to the Muricidae family is reported from Algarve, south coast of Portugal for the first time and is a new record for the biodiversity of the Portuguese malacological fauna and northeastern Atlantic waters. This species with a medium-size shell for the genus (14–16 mm) was initially sam...

The common pandora, Pagellus erythrinus, is a commercially important seabream for coastal fisheries in the north and central eastern Atlantic. Age, growth and reproductive aspects of the southern Portuguese population were estimated by analysing 386 specimens ranging in total length (TL) from 12.0 to 44.8 cm. Ages were estimated by counting growth...

The African hind Cephalopholis taeniops (Valenciennes, 1828) is one of the most important commercial demersal species caught in the Cape Verde archipelago. The species is closely associated with hard substrate and is one of the main attractions for SCUBA divers. In January 2006 a former Soviet fishing vessel - the Kwarcit - was sunk off Santa Maria...

The striped sea bream, Lithognathus mormyrus, used for this population dynamics study were obtained from longline catches and market sampling in the Algarve (south Portugal). The macroscopic analysis of the gonads and the gonad somatic index showed that the south Portuguese population of L. mormyrus spawns mainly between late spring and summer (Jun...

Weight2013length relationships (WLRs) are presented for 54 species sampled by several types of fishing gear between February 2004 and May 2007, in the Arade estuary (southern Portugal). WLRs for six species are presented for the first time.

Acoustic telemetry and standard tag-recapture were used to determine the home range and residency of juveniles and sub-adults of Diplodus sargus and Diplodus vulgaris in the Ria Formosa (Portugal) coastal lagoon. Maximum time between recaptures for the standard tag-recapture method was 128 days for D. sargus and 30 days for D. vulgaris. The majorit...

Three hatchery produced and reared (HPR) and five wild white sea bream (Diplodus sargus) were double tagged with Vemco V8SC-2L acoustic transmitters and Floy Tag T-bar anchor tags, and released on artificial reefs located near a natural reef off the southern coast of Portugal. Passive telemetry was used to monitor movements of the white sea bream o...

The faunal communities of four intertidal habitats namely sand, mud, seagrass (Zostera noltii) and seagrass patches (mixSM) of a temperate coastal lagoon, Ria Formosa (southern Portugal), were sampled. A total of 47 species were taken in 428 bottomless drop sampler samples, with the highest number of species and the more commonly occurring species...

The catches and discards of trawlers, seiners and trammel netters were studied in the Algarve (southern Portugal) using observers onboard commercial fishing vessels. Species diversity was high, with 236 species recorded as occasionally, frequently or regularly discarded. Mean discard rates per trip were 0.13, 0.20, 0.27, 0.62 and 0.70, respectively...

Non-commercial invertebrate discards in an experimental trammel net fishery were studied in relation to selectivity of the gear, depth, soak time and season. Forty experimental fishing trials were carried out over a 1-year period with six combinations of small mesh (100, 120 and 140 mm) inner and large mesh (600 and 800 mm) outer panels. On average...

Fisheries bycatches and discards constitute a significant problem in many fisheries worldwide. Unlike the pelagic purse-seine, the demersal purse seine usually targets high commercial value demersal species such as sea breams (e.g., Diplodus spp., Pagellus spp., Sparus aurata) and the European sea bass (Dicentrarchus labrax), while discards consist...

Otoliths and scales were used to determine age and growth of: Boops boops (Linnaeus, 1758), Diplodus vulgaris (Geoffroy Saint-Hilaire, 1817), Diplodus sargus (Linnaeus, 1758), Lithognathus mormyrus (Linnaeus, 1758), Pagellus acarne (Risso, 1827), Pagellus erythrinus (Linnaeus, 1758) and Spondyliosoma cantharus (Linnaeus, 1758). These structures cam...

Fish communities of the Ria Formosa coastal lagoon (south Portugal) were sampled on a monthly basis with a beach seine at 4 sites, during two different time periods: 1980–1986 and 2001–2002. Community indices, species ranking and multivariate analysis were used in order to identify changes in the fish community between the two time periods. A total...

Several juvenile specimens of Sparisoma cretense, a previously unrecorded species, were caught using beach seining in Ria Formosa.The hypothesis that these occurrences are related with climatic changes is discussed.

Monografia de divulgación sobre las caracteristicas biológicas y de la pesca de distintas especies de interes comercial de este ambito geografico que redunde en la optimización de la gestión de los recursos pesqueros. Esta monografia forma parte del capítulo de transferencia de resultados y divulgación derivada parcialmente de los trabajos realizad...

Samples of Boops boops ranging from 7.4 to 30.5 cm were obtained mainly by longline, supplemented by beach seining in the Ria Formosa lagoon, and by market sampling in the Algarve (southern Portugal). The macroscopic analyses of the gonads and the gonad somatic index showed that the south coast of Portugal B. boops spawn mainly from late winter to...

Trammel net size selectivity was studied for the most important métiers in four southern European areas: the Cantabrian Sea (Atlantic, Basque Country, Spain), the Algarve (Atlantic, southern Portugal), the Gulf of Cádiz (Atlantic, Spain) and the Cyclades Islands (Mediterranean, Aegean Sea, Greece). These métiers were: cuttlefish (Sepia officinalis)...