Karim Erzini

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

Fisheries are one of the most important food sources for human consumption whilst being amongst the most impacting and extractive activities happening within the marine environment, which makes it imperative to properly manage this activity. To improve fisheries management, the precise quantification of fishing effort is of the outmost importance....

The present study, covering 2018-2022, evaluated the cetacean interactions with a bottom-set net fishery along the mainland Portuguese Southern coast (Algarve), estimating bycatch, depredation, gear damage and net length influence on Landing per Unit Effort (LPUE). The fishery employed various métiers (gillnets-mesh sizes: < 60, 60-75, 80 and 220 m...

The widespread adoption of acoustic telemetry has transformed our understanding of marine species' behavior and movement ecology. However, accurately interpreting telemetry data, especially concerning tagging mortality, is essential for drawing valid conclusions. In this study, we scrutinized tagging mortality in 223 individuals across 14 species a...

The larger carangid Caranx ignobilis is one of the key commercial fisheries operated by traditional fishermen on the Kanyakumari coast of Tamil Nadu, India, using larger meshed gillnet and drift hand lines. No selectivity study was conducted for this species in chosen study area; selectivity studies were conducted for C. ignobilis using different l...

Information on population structure and connectivity of targeted species is key for proper implementation of spatial conservation measures. We used a combination of genomics, biophysical modelling, and biotelemetry to infer the population structure and connectivity of Atlantic meagre, an important fisheries resource throughout its distribution. Gen...

Argyrosomus regius (commonly referred to as meagre), is one of Europe’s largest coastal bony fish species and supports important recreational and commercial fisheries in the Atlantic and Mediterranean coasts. Demand for this species, and more recently for their swim bladders, has led to regional population declines and growing importance as an aqua...

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...

Marine plastic litter, originating from land-based sources, enters the marine environment by passing through coastal ecosystems such as lagoons and estuaries. As early life history stages (ELHS) of many commercially important fish species rely on these transitional areas as nursery grounds, we hypothesized that they encounter a spatial gradient of...

Ce rapport présente une évaluation monétaire des services écosystémiques fournis par les herbiers marins en Afrique de l’Ouest. Conduite par l’Université de Portsmouth (UK) avec le soutien du CCMAR (Portugal), de l’ONG Azul e Verde (Cabo verde), de l’IBAP (Guinée-Bissau), du CRODT (Sénégal), de l’IMEDEA (Espagne) et de l’UTA (Cabo Verde) ainsi que...

Deep‐water sharks are among the most vulnerable deep‐water taxa because of their extremely conservative life‐history strategies (i.e., late maturation, slow growth, and reproductive rates), yet little is known about their biology and ecology. Thus, this study aimed at investigating the trophic ecology of five deep‐water shark species, the birdbeak...

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...

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...

In the multi-gear coastal fleet in the Algarve (South Portugal), fishers own licenses for various fishing gears. However, they generally do not use all these licenses, and therefore, it is difficult to estimate the impacts this fleet has on the local environment. In this study, two types of questionnaires were used directed to the local fishers fro...

The coastal waters off Western Iberia are an important fishing ground and a marine megafauna foraging area. Overlap between fishery target species and the diet of several air breathing marine megafauna species can lead to negative interactions and consequently conservation and economic issues. This work aimed to assess marine megafauna (cetaceans,...

The short-term site fidelity of intertidal fish species was studied in a rocky intertidal zone in southern Portugal using visible implant elastomer tagging. Eleven fish species were caught, tagged and released, seven of which were recaptured. The larger tide pool with the highest complexity level and located at a lower position in the shore level d...

Accuracy in reporting captures is a key element to achieve fisheries sustainability. However, identification of the catches might be a challenge when two or more species are morphologically similar and caught jointly, like the mixed fisheries of black hakes in East Atlantic African waters. Black hakes (Merluccius senegalensis and M. polli) are toug...

This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue econom...

The multi-gear coastal vessels in the Algarve (South Portugal) own licenses for various fishing gears. However, it is generally uncertain what gears they use, which is problematic as each individual gear is responsible for unique impacts on the resources and the environment. In this study, landing profiles identified for the multi-gear coastal flee...

Microplastic (MP) pollution is increasing worldwide and affecting aquatic fauna in different ways, which endangers current aquatic resources in a still unknown extent. MP-induced threats to marine fauna are critical for developing countries, where waste treatment may be not optimal and coastal communities rely heavily on marine resources for dietar...

While bycatch, the unintentional catch of untargeted species, is one of the main threats to large marine species such as cetaceans, reef sharks and turtles, also known as megafauna, fishers can also be negatively impacted by bycatch. Understanding local fisheries profiles, fishers’ demography and their opinion is thus a necessary part of the strate...

Following the implementation of the European Council EC Regulation 2016/2336, which restricts bottom trawling below 800 m for vessels capturing deep-sea fish species, the quantification and characterization of the fishing activities at those depths became essential to evaluate potential negative economic impacts. In this study, the activity of the...

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 implementation of marine protected areas (MPAs) has been widely used as a tool to manage and conserve marine resources and services. Yet, to date, the reserve effect is still weakly evaluated, particularly for soft‐sediment habitats. • The Arrábida MPA, considered as a biodiversity hotspot, was fully established in 2009 on the west coast of P...

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...

This is the first attempt to apply an expert-based ecological vulnerability assessment of the effects of climate change on the main marine resources of Portugal. The vulnerability, exposure, sensitivity, adaptive capacity, and expected directional effects of 74 species of fish and invertebrates of commercial interest is estimated based on criteria...

Relationship between overall vulnerability, directional effects and indicators

Expected environmental change in the context of climate change

Bootstrap analysis

Description of the indicators used during the vulnerability assessment

Selection of species

Results of the vulnerability assessment under climate change scenario RCP 4.5.

Smartphone applications (apps) that target recreational fishers are growing in abundance. These apps have the potential to provide data useful for management of recreational fisheries. We surveyed expert opinion in 20, mostly European, countries to assess the current and future status of app use in marine recreational fisheries. The survey revealed...

Current fishing practices often do not allow adequate selection of species or sizes of fish, resulting in unwanted catches, subsequently discarded, with the consequent negative effects on both marine communities and fisheries profitability. The cross-analysis of density patches of potential unwanted catches and distribution of fishing effort can su...

This document serves as the first proposal for management recommendations (MR1) for each of the FarFish case studies. MRs are formal arrangements between a management authority and the operators in the respective case studies. It specifies the partners in the fishery and their respective roles, the agreed objectives for the fishery, the management...

With the global increase of marine protected area (MPA) implementation, the need for monitoring and the evaluation of their effectiveness becomes ever more important. Currently there is a severe lack of information about the protection effects of soft-substrate ecosystems. While many different methods have been established for the monitoring of har...

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...

Discarding has been a common practice in multispecies trawl fisheries since the first trawlers were used. To date there have been no studies reporting an integrated analysis of discarding in the gulf of Cadiz (SW Spain, GoC) to evaluate and support the latest fisheries policies, specifically the Landing Obligation (European Union Regulation 1380/20...

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. At present, the Gulf of Cadiz (GoC) landing ports are not ready to comply with this regulation. Within this frame...

Marine recreational fishing (MRF) in Portugal is a traditional leisure activity with considerable importance for coastal populations. In the absence of available information from the national data collection framework, this article aims to review the existing information on MRF across the country. MRF was an open access fishery until recently, but...

Previous laboratory feeding experiments, representing the state-of-the-art methodology to investigate micro-plastic (MP) ingestion and its impact for fish, tend to disregard both the significance of applying realistic MP densities and the potential relevance of biofilm-coating for ingestion probability. This experiment assessed the uptake of either...

The perceptions of fishers towards the Arrábida Marine Park, a marine protected area (MPA) in the west coast of Portugal, were studied through face-to-face interviews in two different moments of the MPA life cycle. Fishers' perceptions about the MPA and the impact it had on the fishing activity over time were identified just before the full impleme...

The implementation of spatial protection measures is currently a priority in batoid species' conservation strategies, but their spatial ecology remains largely unknown. We provide some preliminary insights into the movement patterns of the white skate (Rostroraja alba), a batoid classified as Critically Endangered in European waters. Three individu...

The European Union Regulation No 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. At present, the gulf of Cádiz (GoC) landing ports are not ready to comply with this regulation; a number of ke...

Current international commitments on ocean protection targets include protecting 10% of the ocean through marine protected areas (MPAs) until 2020, while also complying with efficiency and equity requirements. This has led to a race to designate large MPAs, but despite the valid marine conservation efforts, conferring adequate protection is still a...

This report contains an evaluation of the governance structures of the EU long-distance fishing fleet in the six case studies of the FarFish project. These case studies include two high-seas fisheries and four fisheries that are based on Sustainable Fisheries Partnership Agreements (SFPAs) between the EU and coastal states. All of these fisheries a...

The concentration of the population in coastal regions, in addition to the direct human use, is leading to an accelerated process of change and deterioration of the marine ecosystems. Human activities such as fishing together with environmental drivers (e.g. climate change) are triggering major threats to marine biodiversity, and impact directly th...

The rule of thumb in marine trophodynamics indicates that the bigger an organism, the higher its trophic level (TROPH). This generalization leads to the assumption that fishes increase their TROPH with growth. However, a recent review showed that for many species, TROPH does not increase with body size, suggesting that size-independent feeding is n...

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...

Along the Portuguese continental coast, the Sardine Portuguese Purse Seine Fishery (SPPSF) interacts with dolphins, particularly with the common dolphin, Delphinus delphis. The level of this interaction is directly correlated with fishing effort and sardine, Sardina pilchardus, catch. This is mainly attributed to the fact that sardine, the target o...

Introducción: La pesquería de jaiba de la Ciénaga Grande de Santa Marta está sometida a una fuerte presión sobre los individuos inmaduros, lo que ha conllevado a su sobrepesca. Objetivo: Se determinaron la dimensión y la ubicación de ventanas de escape para facilitar la salida de individuos con tamaños no deseados. Materiales y métodos: Mediante...

The global number of marine protected areas grew exponentially in the last decade to meet international targets. Most of them are partially protected areas (PPAs). Yet, their ecological effectiveness remains unclear due to the high variability of allowed uses. Here, we performed the first global meta-analysis of PPAs following a new regulation-base...

We used a new, easy to use, highly selective, low impact and cheap method of sampling in the swash zone of a sandy beach to obtain catch per unit effort data (CPUE) for Pennant's swimming crab, Portumnus latipes (Pennant, 1777). Metal stakes baited with sardines were used to attract the crabs that were caught by hand. Crab density was estimated bas...

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...

We analyzed three acoustic telemetry datasets of single tagged individuals to argue that, at a time of data deficiency, “solo datasets” have the ability to uncover singular patterns. Here, a greater amberjack (Seriola dumerili), a female school shark (Galeorhinus galeus) and a Salema, (Sarpa salpa) provided relatively long and insightful individual...

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...

A Sort‐X grid device with four different bar‐spacing grids (25, 30, 40 and 50 mm) was tested in the Gulf of Cádiz (GoC) on‐board commercial trawlers. A total of 83 fish, five crustacean and nine cephalopods species were sampled in 282 hauls. Most of the target and commercial bycatch species were sorted out by the grid with the exception of hake. Me...

The number of marine protected areas (MPAs) has grown exponentially worldwide over the past decade in order to meet international targets. Most of these protected areas allow extraction of resources and are therefore designated as “partially protected areas” (PPAs). However, the effectiveness of PPAs remains unclear due to the high variability of u...

Although the bivalve dredge used on the Algarve coast (southern Portugal) is highly selective for the target species , in some periods of the year the bycatch can exceed the catch of the commercial species. The present study aimed to quantify the bycatch and discards, estimate damage and mortality, and propose management measures to minimize discar...

Numerous studies over the last decades have focused on marine protected areas (MPAs) and their effects on fish communities. However, there is a knowledge gap regarding how species that live associated with soft-substrates (e.g., sand, mud) respond to spatial protection. We analyzed abundance, biomass and total lengths of the soft-bottom fishes in a...

Barplots of fish abundance and biomass per protection level and substrate Barplots of mean (±standard error) fish abundance (A: CPUE n⋅500 m−1) and biomass (B: BPUE kg⋅500 m−1) per protection level and substrate (sand, mud).

Mean species abundance and biomass for each protection level and period Mean (and standard error - SE) species abundance (CPUE - n⋅500 m−1) and biomass (BPUE - kg⋅500 m−1) according to period (Period 1, Period 2) and protection level (BA - buffer area; PPA - partially protected area; FPA - fully protected area). Only species with frequency of occur...

Discriminant species at each leaf of the multivariate regression tree Discriminant species at each leaf (terminal node) of the multivariate regression tree analysis (Leaf I - Muddy BA & PPA; Leaf II - Muddy FPA; Leaf III - Sandy BA; Leaf IV - Sandy PPA & FPA, Period 1; Leaf V - Sandy PPA & FPA, Period 2). Indicator values (IndVal) are shown (specie...