Despite their ecological importance, discarded species with low commercial value are often overlooked in marine research. This study examined the age structure and feeding habits of the large-scaled gurnard (Lepidotrigla cavillone) and the spiny gurnard (Lepidotrigla dieuzeidei) in the Gulf of Cádiz (SW Iberian Peninsula). A total of 225 specimens were collected during 19 fishing trips at depths of 15–550 m. Ages were estimate...

Beaches are among the world's most important coastal ecosystems, within which surf zones are crucial providers of essential ecosystem services to humans. We completed the first estimate of current and potential monetary value of fishery resources in surf zones of beaches on the southwestern Iberian Peninsula. Over 1 year, five beaches in the Gulf of Cádiz were sampled using a beach seine. For monetary valuation, average first‐...

Accuracy of catch landing data reported by captains of commercial vessels is crucial in the assessment of marine species stocks and in fisheries policy and management. However, this data can be subject to estimation biases, such as a tendency to inflate some catches (to the detriment of others) and refusal to fill in logbooks. We assessed the accuracy of catch reports from the Spanish tropical tuna purse seine fleet (which acc...

Various commercial fish species utilize different coastal habitats as nurseries in their juvenile stages, with surf zones being particularly crucial due to the protection and abundant food resources they offer. Among the species that rely on these areas are the spotted seabass (Dicentrarchus punctatus) and the European seabass (Dicentrarchus labrax). This study aimed to investigate the age and feeding habits of surf zone speci...

The accurate labeling of species and size of specimens plays a pivotal role in fish auctions conducted at fishing ports. These labels, among other relevant information, serve as determinants of the objectivity of the auction preparation process, underscoring the indispensable nature of a reliable labeling system. Historically, this task has relied on manual processes, rendering it vulnerable to subjective interpretations by th...

Surf zones are crucial habitats for many fish species, where they spend the initial stages of their lives, finding food and shelter. One such species is the pompano ( Trachinotus ovatus ). The aim of this study was to examine the age and diet of the pompano within the surf zone, along with any potential variations in the environment. The average size of the specimens was 10.61 ± 4.91 cm. The length–weight relationship was tota...

In many fisheries, such as trawl fisheries, sharks appear among the catches as bycatch or discards, and these species include velvet belly ( Etmopterus spinax ) and blackmouth catshark ( Galeus melastomus ). The objective of this study was to research the feeding habits of both species in the Gulf of Cádiz and to identify possible differences in diet depending on size and time of day. The most frequent sizes were 12–16 cm for...

Otoliths are widely employed in marine sciences to gain insights into fish growth, age, migrations, and population structure. This study investigates the relationships between morphometric measurements, otolith characteristics, and length size patterns in the brown comber ( Serranus hepatus ) from the Gulf of Cádiz, a species discarded in artisanal trawl fisheries. Our findings reveal significant changes in otolith shape indic...

The brown comber (Serranus hepatus) is a small benthopelagic species with no commercial value, primarily caught by bottom trawls as a by-catch. In this work, we studied the feeding habits of this species. For this purpose, samples were obtained from the trawl fleet within the different editions of the ECOFISH project carried out between 2019 and 2022. A total of 1534 individuals were analyzed. In the diet analysis, various fac...

Bycatch is a significant issue in global fisheries and understanding the length–weight relationships (LWR) of fish species can provide valuable insights for stock assessment and management efforts. In this study, we estimated the LWR of 74 fish species in trawl fleet discards from the Gulf of Cadiz, including 24 species for which LWR data had not been previously reported in this region. LWR was calculated from the formula W =...

Several studies have shown the effect of climatic oscillations on fisheries. Small pelagic fish are of special global economic importance and very sensitive to fluctuations in the physical environment in which they live. The main goal of this study was to explore the relationship between the North Atlantic Oscillation (NAO), the East Atlantic pattern (EA), and the Arctic Oscillation (AO) on the landings and first sale prices o...

The within-year dynamics of the juvenile fish community over a shallow nursery seagrass-dominated habitat (Posidonia oceanica) in a Mediterranean Bay was compared between two surveys separated 50 years (1960 and 2012-2013). A nocturnal survey over depths ranging from 2 to 10 m over patched seagrass meadows was conducted for one year (2012-2013) through 72 epibenthic tows spread fortnightly in 4 close-by stations, mimicking a s...