Achieving sustainable resource use is a priority to meet future challenges. The Gulf of Cádiz, located in the Atlantic waters of southern Europe, is home to a significant fishing fleet due to the richness and diversity of its ecosystems. Managing this area is complex due to the diversity of variables, including social, ecological, and oceanographic factors.
View Article and Find Full Text PDFMarine microalgae are a rich reservoir of natural compounds, including bioactives. Nonetheless, these organisms remain fairly unexplored despite their potential biotechnological applications. Culture collections with diverse taxonomic groups and lifestyles are a good source to unlock this potential and discover new molecules for multiple applications such as the treatment of human pathologies or the production of aquaculture species.
View Article and Find Full Text PDFWe present the description of defensive behavior in wild against conger eel () attacks based on three video sequences recorded by recreational SCUBA divers in the eastern Atlantic off the coast of Galicia (NW Spain) and in the Cantabrian Sea (NW Spain). These records document common traits in defensive behavior: (1) the octopuses enveloped the conger eel's head to obscure its view; (2) they covered the eel's gills in an attempt to suffocate it; (3) they released ink; (4) the octopuses lost some appendages because of the fight. In the third video, the octopus did not exhibit the defensive behavior described in the first two videos due to an inability to utilize its arms in defense, and the conger eel's success in capturing octopuses is discussed.
View Article and Find Full Text PDFThe Galician Rías (northwestern Spain) are periodically affected by harmful algal blooms (HABs), mostly dinoflagellates, which pose a challenge to aquaculture activities due to the accumulation of biotoxins in shellfish. Typically, reddish blooms in the Rías are associated with non-toxic species like Noctiluca scintillans, with a few exceptions such as Alexandrium minutum, a producer of paralytic shellfish toxins (PST). Here, a useful approach is presented for monitoring reddish blooms through satellite imagery based on three case studies, two of them belonged to monospecific blooms of red Noctiluca scintillans, and the third to a bloom of Alexandrium spp.
View Article and Find Full Text PDFThe use of cephalopod beaks in ecological and population dynamics studies has allowed major advances of our knowledge on the role of cephalopods in marine ecosystems in the last 60 years. Since the 1960's, with the pioneering research by Malcolm Clarke and colleagues, cephalopod beaks (also named jaws or mandibles) have been described to species level and their measurements have been shown to be related to cephalopod body size and mass, which permitted important information to be obtained on numerous biological and ecological aspects of cephalopods in marine ecosystems. In the last decade, a range of new techniques has been applied to cephalopod beaks, permitting new kinds of insight into cephalopod biology and ecology.
View Article and Find Full Text PDFThe initial development of seahorse juveniles is characterized by low digestion capabilities. Stable isotope analysis is an effective tool in studies of trophic food webs and animal feeding patterns. The present study provides new insights for the understanding of growth and food assimilation in early developing seahorses following a laboratory diet switch.
View Article and Find Full Text PDFMicroplastics (MPs) are a major concern for marine ecosystems since they can be ingested by a wide range of marine species and transmitted through the food web. However, the potential hazardous impact of MPs in fishes, especially in early developing stages, is relatively unknown. In the present study, we assessed for the first time the ingestion and retention of MPs in early developing seahorses Hippocampus reidi.
View Article and Find Full Text PDFAlbacore Thunnus alalunga and skipjack tuna Katsuwonus pelamis are highly migratory species that are usually caught together in the Western Mediterranean. These species are top predators that are highly affected by the biomagnification process through the trophic chain. Bioaccumulation pattern of the main metal pollutants (mercury, Hg; lead, Pb; and cadmium, Cd) were analyzed in muscle tissues of 52 individuals (26 T.
View Article and Find Full Text PDFBackground: Syngnathid fishes (Actinopterygii, Syngnathidae) are flagship species strongly associated with seaweed and seagrass habitats. Seahorses and pipefishes are highly vulnerable to anthropogenic and environmental disturbances, but most species are currently Data Deficient according to the IUCN (2019), requiring more biological and ecological research. This study provides the first insights into syngnathid populations in the two marine Spanish National Parks (PNIA-Atlantic- and PNAC-Mediterranean).
View Article and Find Full Text PDFIsotopic stable analysis (SIA) is a powerful tool in the assessment of different types of ecological and physiological studies. For that, different preservation methods for sampled materials are commonly used prior to isotopic analysis. The effects of various preservation methods (freezing, ethanol and formaldehyde) were analyzed for C:N, and δC and δN signals on a variety of tissues including dorsal fins (three seahorse and two pipefish species), seahorse newborns (three seahorses species), and prey (copepods and different stages of ) commonly used to feed the fishes under rearing conditions.
View Article and Find Full Text PDFThe muscle and textural parameters were analyzed in four myotome zones (epaxial upper, hipoaxial upper, epaxial bottom, and hipoaxial bottom) in seven diploids (D) and seven triploids (T) turbot specimens. Diploid specimens showed the highest values of the size and number of white fibers in the epaxial zones, being such values higher in female than male specimens. In triploid specimens, the highest fibers sizes were found in the upper zones (epaxial and hipoaxial), whereas the lowest number and density of fibers were found in the epaxial upper zone.
View Article and Find Full Text PDFKleptoplastic mixotrophic species of the genus are cultured by feeding with the ciliate , itself a kleptoplastic mixotroph, that in turn feeds on cryptophytes of the // (TPG) clade. Optimal culture media for phototrophic growth of and from the Galician Rías (northwest Spain) and culture media and cryptophyte prey for from Huelva (southwest Spain) used to feed , were investigated. Phototrophic growth rates and yields were maximal when and were grown in ammonia-containing K(-Si) medium versus f/2(-Si) or L1(-Si) media.
View Article and Find Full Text PDFTurbot specimens were kept at three temperatures (T s ): warm (W) (21-22 °C), ambient (A) (17-18 °C) and cold (C) (13-14 °C) during the larval and early postlarval stages. At 90 days posthatching (dph), all of them were transferred to ambient T until 190 dph. At 2-3 dph, the specimens showed a monolayer of red muscle and immature white fibres; external or dermomyotome cells (presumptive myogenic cells) were observed on the surface of the red muscle.
View Article and Find Full Text PDFThe first description of cannibalism in wild adult Octopus vulgaris is presented from 3 observations made in the Ría de Vigo (NW Spain), which were filmed by scuba divers. These records document common traits in cannibalistic behavior: (a) it was intercohort cannibalism; (b) attacks were made by both males and females; (c) in 2 of the records, the prey were transported to the den, which was covered with stones of different sizes; (d) the predator started to eat the tip of the arms of its prey; (e) predation on conspecifics occurred even if there were other abundant prey available (i.e.
View Article and Find Full Text PDFBackground: Gene expression analysis by reverse transcription quantitative PCR (qPCR) is the most widely used method for analyzing the expression of a moderate number of genes and also for the validation of microarray results. Several issues are crucial for a successful qPCR study, particularly the selection of internal reference genes for normalization and efficiency determination. There is no agreement on which method is the best to detect the most stable genes neither on how to perform efficiency determination.
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