Durante décadas, la comunidad científica ha advertido sobre los límites del crecimiento en nuestro planeta mediante la analogía de “que viene el lobo”. Al situarnos en 2026, los datos confirman que el umbral crítico ha sido superado. Factores como la sobreexplotación de recursos, la acidificación oceánica, el calentamiento superficial del mar y concentraciones de CO₂ que superan las 425 ppm se conjugan para situar a la biosfera en un estado de sobrecapacidad. ¡El lobo ya está aquí!. Según los indicadores de la Global Footprint Network, la demanda antropogénica de recursos ha superado la biocapacidad de renovación de los ecosistemas. Este desequilibrio nos sitúa en un déficit ecológico donde consumimos biomasa a una velocidad superior a su regeneración natural. Para este año, se proyecta que el Día de la Sobrecapacidad Global se manifieste a principios de agosto, esto quiere decir que consumimos anualmente casi el doble del flujo de recursos que la Tierra puede generar, comprometiendo la viabilidad planetaria a largo…pero no tan largo plazo.

Dissolved oxygen (DO) concentrations in subtropical and tropical mangrove ecosystems frequently fluctuate, prompting aquatic organisms to adapt to these variations. Oxygen deficit during tidal changes, eutrophication, and stagnant water conditions may modulate physiological responses and limit bivalve survival. This study evaluated the effects of oxygen stress (anoxia, hypoxia, and air exposure) on haematological parameters (haemocyte viability and count), lysosomal membrane stability (LMS), osmotic fragility (OF), content of haemoglobin (Hb), protein, triglycerides, and glucose, as well as activity of lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PDH) and catalase (CAT) in broodstock of the mangrove cockle Anadara tuberculosa. Preliminarily, the mean survival time under oxygen stress during 12 d was estimated. Subsequently, mature individuals were exposed to hypoxia (2 mg L-1), anoxia (0 mg L-1), air exposure (emersion), normoxia (6 mg L-1), and cycles of emersion and immersion (6-h intervals) during 96 h. Following exposure, spawning induction by thermal shock and D-veliger larval production were estimated. Haemocyte viability declined in cockles exposed to anoxia, while Hb increased under anoxia and air exposure. Glucose, triglycerides, proteins, LMS, OF, and LDH activity remained unchanged. However, G6PDH activity increased in cockles exposed to anoxia, whereas CAT activity increased under hypoxia, anoxia, and air exposure. Previous air exposure and anoxia increase gamete release during spawning induction, potentially associated with enhanced reproductive output. Physiological responses represent early-stage adjustments to varying degrees of oxygen deprivation, demonstrating the adaptive capacity of A. tuberculosa to both prolonged and acute oxygen stress and underscoring its remarkable resilience to the fluctuating oxygen conditions typical of mangrove ecosystems.

The tropical–subtropical mussel Mytella strigata (Hanley, 1843) has emerged as a rapidly spreading marine invader, establishing populations across Asia, North America, and parts of the Indo-Pacific within the past two decades. This review synthesizes current knowledge on its invasion dynamics, biological traits, introduction pathways, and ecological and socioeconomic impacts, drawing on published records from both native and invaded ranges. Evidence indicates that ballast water discharge, aquaculture-mediated transfers, and biofouling on vessels and infrastructure are the primary vectors facilitating spread. The invasion success of M. strigata is associated with a combination of physiological tolerance, rapid reproduction, and strong attachment capacity, although the expression and consequences of these traits vary regionally. Reported impacts include biofouling of aquaculture systems, competitive interactions with native bivalves, alteration of benthic–pelagic coupling, and accumulation of contaminants with potential implications for food safety. Despite increasing detection, management responses remain fragmented and largely reactive. By integrating invasion chronology, trait-based mechanisms, and regional case studies, this review identifies key knowledge gaps and outlines priorities for monitoring, risk assessment, and biosecurity in a context of expanding global trade and climate-driven environmental change.

The Manabí oyster (Crassostrea sp.) is considered a potential emerging aquaculture species for estuarine environments in the Tropical American Pacific, particularly in equatorial regions. While preliminary studies on its biological feasibility for cultivation are underway and although its mitochondrial genome has been recently described, its taxonomic identity has remained unclear until now. Here we conducted a comparative morphological study of natural and cultured Manabí oysters with Crassostrea corteziensis from Boca de Camichín, Nayarit, Mexico, and performed molecular identification using mitochondrial DNA genes (cytochrome c oxidase subunit I and 16S ribosomal RNA) to construct phylogenetic trees. Although evident morphological differences exist between the Manabí oyster—primarily a protuberance on the right valve of natural Manabí oysters and a blackish color in both natural and cultured Manabí oysters—and the oyster from Boca de Camichín, their phylogenetic analysis provides conclusive evidence that the Manabí oyster from the Chone River in Ecuador is conspecific with Crassostrea corteziensis. This clarification has direct implications for aquaculture planning and policy.

Kappaphycus alvarezii is widely cultivated in tropical regions, with its growth influenced by cultivation techniques. Despite extensive global studies, there is a knowledge gap in Ecuador regarding the performance of different strains and systems under local specific conditions. The growth performance of K. alvarezii strains (green, brown, and red) cultivated in Ecuador using “tubular nets” and “tie-tie systems” was evaluated. Fifteen thalli from each strain were grown for 70 days, with daily measurements of water temperature, salinity, dissolved oxygen, turbidity, and nutrient levels. No significant differences were detected between the systems, and their DGR growth rates were high for algae culture development (4.0 ± 0.92

The effect of time on mab & eacute; pearl formation in the mother-of-pearl oyster Pinctada mazatlanica was evaluated under suspended culture in Bahia de Car & aacute;quez, Chone River estuary, Manabi, Ecuador. Oysters measuring 80-90 mm were grafted with three hemispherical nuclei (11 mm in diameter and 6 mm in height): one in the left valve and two in the right valve (left and right sides). Cultivation occurred from September 2023 to January 2024 in lantern nets suspended at a depth of 1-2 m from a floating aquaculture platform located in waters 6-8 m deep. Monthly assessments included survival, nacre deposition on the nuclei, and pearl quality (classified into commercial categories AAA, AA, A, B, and noncommercial-NC). Cumulative survival decreased in the last 2 mo, reaching 80.7% +/- 17.95% by the end of the study. Nacre deposition varied significantly, with the highest layer observed in the right valve at the end of the study. Initially, mab & eacute; pearl quality was predominantly grade B (>35%) and noncommercial (>30%), followed by grade A (15%-28%), AA (3%-17%), and AAA (0%-7%). At the end of the experiment, the proportion of noncommercial pearls in the right valve significantly decreased, whereas AA (17%) and AAA (7%) categories increased. An association analysis revealed a positive correlation between nacre deposition and AA category pearls. These findings suggest that the nucleus's placement on the right side of the right valve and a minimum cultivation period of 4 mo or more are crucial for producing higher quality pearls and better nacre deposition in Bahia de Car & aacute;quez, Chone River estuary.

Global awareness of introduced species as one of the primary drivers of biodiversity change—causing environmental impacts, and economic and social effects—emphasizes the need to enhance our understanding of these species. Developing a comprehensive database will enable policymakers to identify global bioinvasion patterns and strengthen their capacity to manage them effectively. Aquatic mollusks play a crucial role in the ecosystems they inhabit, influencing food webs and nutrient cycling, and habitat formation and modification. They are also the dominant group in aquaculture, contributing significantly to the economy while also causing economic losses through macrofouling and posing health risks. Despite their importance, information on the introduction, establishment, and dispersal of mollusk species in South America remains scarce and is often confined to the grey literature. With the aim of organizing, increasing, and strengthening the knowledge of non-native and transplanted mollusks in general and aquatic mollusks in particular, 29 specialists in the introduced mollusks of South America, from seven countries, have been working collaboratively since 2016. Each member contributes expertise, data, and bibliographic resources to build the status of the introduced mollusks in South America and provide critical information to prevent future introductions and transplants. In aquatic environments, 41 non-native mollusk species and 18 transplanted species have been identified. Among them, the bivalve Limnoperna fortunei stands out with the greatest economic effect, while the gastropods Lymnaeidae and Thiaridae represent significant health concerns. Although this research represents a major step forward, it also highlights challenges such as the scarcity of taxonomic studies and the limited investigation of vast areas in South America. The information compiled in this review serves as a resource for researchers, policymakers, and the general public when addressing mollusk bioinvasions in South America.

The invasive species Melanoides tuberculata was detected in culture ponds for shrimp (Penaeus vannamei) and the Pacific fat sleeper fish (Dormitator latifrons) in Manab & iacute;, Ecuador, through morphological and molecular identification using the COI gene. This finding confirms the presence of the Malayan snail in the Amazon-Andes ecoregion, evidencing its wide distribution in South America and its genetic relationship with populations from Iran and the United States, suggesting a recent invasion event in the continent. This is the first report of the species in culture ponds of the shrimp P. vannamei and fish D. latifrons, representing a new habitat and a potential negative factor for aquaculture activities. It is necessary to expand sampling efforts to other regions and conduct genetic analyses to identify lineages with a higher potential for transmitting parasitic infections. This information is crucial for developing early warning systems and effective management strategies. Further studies are needed to assess the potential risks of M. tuberculata in aquaculture systems, such as its ability to transmit parasites to farmed organisms and its possible impacts on human health.

The girdled triton, Linatella caudata (Gastropoda: Ranellidae), is a marine gastropod known to invade bivalve cultures, killing its prey through the injection of biotoxins, thereby posing a significant threat to aquaculture. In this study, we evaluated the hemolytic and acute toxic effects of a bioactive extract obtained from the salivary gland (SG) of L. caudata collected from mariculture baskets in the Gulf of Cariaco, Northeastern Venezuela. Mainly, toxicity on Artemia sp. and haemotoxicity of SG extract on human blood were determined, as well as the identification of compounds from chromatographic fractions using MALDI-TOF mass spectrometry. SG secretions exhibited high toxicity toward Artemia sp. (LC50 = 46.73 µg mL−1) and demonstrated potent haemolytic activity (HC50 = 21.48 µg mL−1). Chromatographic analysis identified four fractions with haemolytic activity, two of which caused oxidative modifications of iron in haemoglobin. One fraction, TR 21.1 min (MM = 1929.29 Da), revealed key peptide sequences that include valine-proline, lysine-arginine, and arginine-lysine, which probably could contribute to cytotoxicity and haemolytic effects. These findings enhance our understanding of the biochemical properties and mechanisms of action of L. caudata biotoxins, highlighting their ecological impacts on marine bivalve aquaculture.

The global production of Pacific white shrimp Penaeus vannamei (Boone, 1931) has increased annually with advances in farming techniques. However, like any open system, it is subject to economic losses from invasive organisms, predators, and diseases. The lagoon mussel Mytella strigata, which massively invades culture ponds, reduces the primary productivity necessary for raising juvenile shrimp and is typically treated with copper sulfate pentahydrate (CuSO4.5H2O) as a molluscicide. In the search for copper sulfate doses that are effective for controlling M. strigata and cultivating P. vannamei, the mean lethal concentration for mussels (LC50; 0.57 mg CuSO4.5H2O L- 1 ) and shrimp (LC50; 2.91 mg CuSO4.5H2O L- 1 ) was estimated. Subsequently, the acute effect of CuSO4.5H2O on biometry and endogenous energy reserves by exposing shrimp to a dose of 1.20 mg CuSO4.5H2O L- 1 , and the amount of metal accumulated and detoxified from the soft tissue and exoskeleton (lethal for mussels and sublethal for shrimp) was evaluated for 12 d, followed by a detoxification period for 5 d. A significant reduction in body mass in CuSO4.5H2O-exposed shrimp was observed. Copper content was higher in the exoskeleton of CuSO4-exposed shrimp (146.3 f 26.2 mu g Cu g- 1 ), decreasing significantly with depuration (97.9 f 26.0 mu g Cu g- 1 ). In the soft tissue, 53.3 f 9.8 mu g Cu g- 1 was accumulated, decreasing to 6.2 f 1.3 mu g Cu g- 1 , showing a higher percentage of detoxification (88.3 %) compared to the exoskeleton (48.5 %). Protein, carbohydrate, and lipid concentrations were not altered during copper exposure and depuration. The results suggest that sublethal exposure to CuSO4.5H2O does not affect survival, and although shrimp biomass decreased (19 % compared to control), there was no effect on their biochemical composition. Our research recommends using 1.2 mg L- 1 of CuSO4.5H2O to control specific events of mussel invasion, which could be included within protocols of low environmental impact and cost.

This review illustrates various aspects of the life cycle of some species of gastropods belonging to the Ranellidae. These species possess a series of characteristics that allow for the wide dispersal of their larval stages (planktotrophic). Combined with their high fecundity and the effectiveness of their predatory behavior, this results in high mortalities of cultivated marine bivalves, both under suspended conditions in the water column and on the seabed. The different organs of their alimentary system and their functions are described. Further, the various strategies and methods developed to control the incidence of these predators in bivalve cultures are detailed. Among the most evident characteristics of most species are: (1) Parental care provided by the egg-laying mother over the egg capsule mass, ensuring effective larval hatching; (2) Indirect larval development, which includes a planktotrophic larva with swimming capability through a velum that allows for geographical expansion; (3) Predatory activity carried out through an alimentary system composed of modified salivary glands that produce biotoxins and a pleuroembolic (eversible) proboscis capable of inoculating the toxins, which quickly incapacitate or kill their prey without needing to perforate their shells, enhancing their predatory capacity.

El efecto de compuestos bioactivos altamente diluidos (CBADs) fue evaluado durante la pre-engorda de juveniles de ostra del Pacífico (Magallana gigas), cultivados en unidades experimentales tipo "surgencia" con flujo ascendente-recirculante de agua y alimento, suministrado mediante aerosifón. Las variables de evaluación fueron las respuestas de crecimiento en peso, volumen y área de la concha. Los CBADs evaluados en el estudio fueron medicamentos Similia® autorizados para uso humano por la Secretaría de Salud de México (T1: CaS (Calcarea sulphurica 30C), T2: BaC (Baryta carbonica 30C), T3: FeP (Ferrum phosphoricum 30C), T4: HeS (Hepar sulphuris 30C), T5: ZiM (Zincum metalicum 30C), y un tratamiento control (agua destilada: C). Los tratamientos se añadieron diariamente al agua de cultivo durante treinta días. Los resultados no mostraron evidencia de que los CBADs hayan mejorado la supervivencia de las semillas de M. gigas, pero fueron efectivos para su crecimiento, ya que FeP (T3) proporcionó un incremento significativo en peso y volumen, mientras que BaC (T2) incrementó significativamente el área de la concha de los juveniles. Estos resultados avalan el potencial que tiene la aplicación de CBADs para mejorar la producción de semillas de ostras, y dado su efecto diferencial, se sugiere continuar los estudios para establecer combinaciones aditivas y sinérgicas que optimicen los rendimientos a obtener durante la producción de semillas en laboratorio.

Ecosystems and biodiversity around the globe face multiple threats, including climate change and invasive species. Non-native species are known for their resilience to disturbances and their ability to thrive more successfully than native species in urbanized or otherwise disturbed areas, and some of them can become invasive. It is a complex challenge to detect, manage, and control such species, which require coordinated efforts from society, government, and the academic community. In this study, the eMIAS (South American Invasive Mollusks Specialists) research group (27 experts from seven South American countries) aim to provide foundational knowledge for management of these species. We compiled and synthesized information on the mollusc species that are native to South America and that have been introduced to other regions of the world. A total of 29 species were detected, including 10 marine, 10 freshwater, and 9 terrestrial. For each species, the area of origin, date and place of introduction, and current distribution were determined. We could determine that (1) most of these introductions have occurred in connection with globalization processes, such as an increase in trade. (2) The potential source regions of those 29 species are also areas that received non-native species from elsewhere (e.g., Europe, Asia). (3) Regions where species introductions have taken place are subject to the impacts of climate change and/or urbanization.

Fresh roes of rock-boring urchin sea Echinometra lucunter lucunter has a high food value, which enhances its fishery and mariculture; however, biochemical composition and development are influenced by environmental conditions. To evaluate protein, lipid, and carbohydrate content, and be able to establish how it varies the storage in the gonads during upwelling (high primary productivity/22-24 degrees C) and stratification (low primary productivity/28-30 degrees C) seasons, adult sea-urchins (> 30 mm) were monthly collected from Lobos Islet (Venezuela). Salinity, temperature, dissolved oxygen, transparency, total seston and chlorophyll a in superficial seawater were averaged. Biometric parameters, sex, reproductive stage, gonadosomatic index (GI), and biomolecule content in the gonads were determined per individual. Gonadal development of E. lucunter lucunter occurs during the upwelling-stratification transition, corresponding with the seawater temperature increase. Biomolecules showed temporal variations associated with gonadal production; a negative relationship existed between the preferential use of carbohydrates and lipids. Maximal gonad production and accumulated carbohydrate and protein were reached during stratification; however, during upwelling synchronized spawns were observed as well as a respective decrease in lipids and carbohydrates. The environmental conditions during stratification stimulate the gonadal development of E. lucunter lucunter , in comparison the coastal upwelling acts as a trigger of synchronized spawning for both sexes. The energy biomolecules are stored in the roes mainly during stratification, using with preference to carbohydrates to metabolic demand.

A total of 381 specimens of the tilapia Oreochromis mossambicus collected monthly from May 2017 to May 2018 in the Laguna de Los Patos, Cumaná, Venezuela, to evaluate reproductive parameters of this non-native species. Significant differences were found in relation to average height and weight between males and females, with the highest values in males. The sex ratio was 1:1.5 (males:females), which deviates significantly from the expected 1:1 ratio. The mean length of sexual maturity (Lm50) was 18.0 cm in females and 20.1 cm in males, reflecting that females mature at smaller sizes than males. The monthly variations of the gonadosomatic index (GSI) and the stages of sexual maturity show two reproductive peaks during the study, in October 2017 and April 2018, coinciding with the rainy and dry seasons in the region respectively. The condition factor (CF) showed significant differences between months, but not between sexes, with an average of 1.87 in females and 1.84 in males. The average absolute fecundity was 921 ± 604.6 eggs per fish, with a relative fecundity of 8.36 ± 3.09 eggs per gram of fish. Differences in oocyte size in mature females confirm that the species can spawn repeatedly over a period, which is considered an important factor for the establishment of tilapia in non-native environments.

Grow-out of the Manabi oyster (Crassostrea cf. corteziensis) under suspended culture conditions from the Chone River Estuary (Manabi, Ecuador) was evaluated. The culture was established in lanterns with 50 oysters/floor for seven months (July 2022 to February 2023) using juveniles (34.9+6.2 mm) collected from natural oyster beds in the same estuary. The growth and survival, as well as environmental variables in the culture site, were monitored. The growth in the shell dimension was continuous, reaching high rates during October and November. At the end of the study, 86.7+6.68 mm anteroposterior length, 110.7+19.04 g dry mass of the whole organism (with 3.7+0.67 g soft tissue), and survival of 92.6+2.62 % were obtained. No association was observed between the patterns of the growth curves and those of the environmental parameters; however, the decrease of body mass (during February 2023) was associated with increased temperature, decreased salinity, and lower phytoplankton content. Oysters of marketable size (80 mm) were obtained after seven months of culture. The results suggest the biological feasibility of cultivating the Manabi oyster C. cf. corteziensis in the Chone River Estuary, which could be an emerging species for aquaculture in Ecuador and the tropical American Pacific.

The depth culture influence (4, 8, and 16 m) and periods (upwelling and non-upwelling) on growth and survival of the pearl oyster Pinctada imbricata during 10 months in the southeastern Caribbean Sea (Cariaco Gulf) were evaluated. Monthly records were taken of survival, body growth, and fouling organisms of the pearl oyster, as well as weekly samples of the temperature, chlorophyll a, and seston of the water culture site. Monthly survival was above 92

Abrupt drops in salinity that occur in tropical estuaries during the equatorial rainy season led to hyposaline conditions which may reduce the populational density of oysters. To assess the effect of saline stress on physiological and metabolic responses of the Manabi oyster (Crassostrea cf. corteziensis) was exposed to 35, 30, 20,10 and 5%o concentrations during 96 h. Inorganic osmolytes, pH, salinity, haemocyanin and protein concentration in the plasma as well as the number of oysters with closed valves were recorded. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and catalase (CAT) activity were analysed. Inorganic osmolytes and internal salinity were elevated in oysters exposed to 35, 10 and 5%o. A significant number of oysters with valve closure was observed in 10 and 5%o, which coincided with a decline in physiological pH and changes in haemocyanin concentrations. AST activity and AST/ALT ratio were reduced under 35, 10 and 5%o, and CAT increased in oysters exposed to 35%o; but protein concentration, LDH and ALP did not show significant variations. Metabolic adjustment and behavior of the Manabi oyster could explain tolerance and survival (at least for a short term) to hyposaline stress in tropical estuarine ecosystems.

Final culture of Magallana gigas (similar to 40 mm) was evaluated in lantern nets at densities of 60, 80, and 100 oysters per floor over 6 months in the Chone River estuary, Ecuador. At the end of the experiment, oysters cultured at 60 oysters per floor exhibited significantly higher survival rates (75%) and growth (111 mm height) compared to those at 80 and 100 oysters per floor (64% survival and 102 mm and 92 mm growth). Oysters at the lower density reached commercial size (80 mm) within 3 months, while at higher densities reached this size after 4 and 5 months. Economic analyses indicated high profitability (58 to 67%), with maximum values at the higher density, although with a notable decline in soft tissue. Therefore, densities of 60-80 oysters per lantern net floor are recommended for the optimal culture of M. gigas in the Chone River estuary.