Polycultured agrarian systems in Ecuadorian Amazonia (also called chakras or swollen gardens) are characterised by a market-oriented crop for the generation of monetary income, for example, cocoa, other agricultural products (e.g., banana and cassava), and livestock for family farm consumption. Moreover, a chakra is an outstanding example of agroforestry production, in which ecological, social and economic elements co-evolve from a set of close and strong connections. In this context, the conservation and transformation of their biological subsystems can be understood as the result of complex interactions between anthropogenic and non-anthropogenic factors. In turn, such interactions are essential to provide food and monetary income to the indigenous community. Relevant agency capabilities exist that could cause an agroforestry system to take a different path of co-evolution, that is, towards greater or lesser sustainability associated with different levels of complexity. In conclusion, chakras have key ecological features that can mitigate the impact of human population growth in Amazonia. Additionally, chakras have their own processes of social self-regulation which enhance the possibilities of adaptation of Kichwa communities to changing environmental conditions, being essential elements in local food sovereignty, equitable gender relations and the respect of ancestral wisdom.

Freshwater fish communities in Ecuador exhibit some of the highest levels of diversity and endemism in the Neotropics. Unfortunately, aquatic ecosystems in the country are under serious threat and conditions are deteriorating. In 2018–19, the government of Ecuador sponsored a series of workshops to examine the conservation status of Ecuador's freshwater fishes. Concerns were identified for 35 species, most of which are native to the Amazon region, and overfishing of Amazonian pimelodid catfishes emerged as a major issue. However, much of the information needed to make decisions across fish groups and regions was not available, hindering the process and highlighting the need for a review of the conservation threats to Ecuador's freshwater fishes. Here, we review how the physical alteration of rivers, deforestation, wetland and floodplain degradation, agricultural and urban water pollution, mining, oil extraction, dams, overfishing, introduced species and climate change are affecting freshwater fishes in Ecuador. Although many of these factors affect fishes throughout the Neotropics, the lack of data on Ecuadorian fish communities is staggering and highlights the urgent need for more research. We also make recommendations, including the need for proper enforcement of existing environmental laws, restoration of degraded aquatic ecosystems, establishment of a national monitoring system for freshwater ecosystems, investment in research to fill gaps in knowledge, and encouragement of public engagement in citizen science and conservation efforts. Freshwater fishes are an important component of the cultural and biological legacy of the Ecuadorian people. Conserving them for future generations is critical.

The present study evaluated the acute inflammatory response induced by carrageenin (500 µg) injected in the swim bladder of Nile tilapia, after fed or not probiotic supplemented diet. Fifty four fish were distributed in six treatments and three replicates: Group A: Fish fed unsupplemented diet: 0.5 mL saline-injected fish; fish injected with 500 µg carrageenin diluted in 0.5 mL saline; Non-injected. Group B: Fish fed probiotic supplemented diet: saline-injected fish; carrageenin-injected fish; Non-injected. Fifteen days after feeding the fish were injected with carrageenin or saline. After six hours, inflammatory exudate was collected, as well as the blood for hematocrit, red blood cell (RBC) and white blood cell (WBC) counts, differential count of leucocytes and phagocytic activity in the blood. Supplementation with probiotic did not influence the RBC, hematocrit and the numbers of lymphocytes and basophils in the blood. The number of neutrophils was significantly higher in supplemented fish injected with carrageenin. Glucose concentration in supplemented and non-injected fish was higher than that observed in the saline injected ones. Probiotic potentialized the migration of cells to the inflammatory focus in the animals injected with the carrageenin irritant. In fish injected with saline and carrageenin occurred the greatest phagocytic activity in the blood in relation to those treatments.

Esta investigación brinda una visión general de la cadena de producción de peces de agua dulce en la Amazonía ecuatoriana, destacando especies como la tilapia (Oreochromis spp.), paco o cachama (Piaractus brachymopus), paiche (Arapaima aff. gigas), sábalo (Brycon amazonicus), bocachico (Prochilodus nigricans) y bagres amazónicos o surubíes (Pseudoplatystoma spp.). La capacidad productiva de las unidades económicas piscícolas, se evaluaron a través de los datos del registro acuícola oficial, complementados con 50 encuestas a productores y 28 entrevistas a actores claves. La tecnología utilizada en los sistemas de producción y procesamiento, los canales de comercialización, el soporte institucional, los recursos humanos y financieros, la investigación y desarrollo fueron caracterizados. Según los datos obtenidos, participan 2.800 productores con distintos niveles de producción, quienes movilizan un intercambio comercial entre 6 a 12 millones de $USD. Los mayores componentes incluyen: i) Oferta regional de carne de pescado por acuicultura entre 1.600 y 3.200 t/año, 95% Tilapia. ii) Oferta mínima de Alevines de 12 millones/año, al menos 0,6 millones de $USD/año, exportados fuera de la Amazonía. iii) Compras de ración artificial por 2 millones de $USD/año, considerando a 0,95 $USD/kg y una tasa de conversión alimenticia (TCA) de 2:1. Se identificaron cinco grupos de cuellos de botella: institucionales, administrativos, comerciales, tecnológicos y socio-ambientales. Se propone abordarlos mediante: armonización legal de los esquemas de regularización de cultivos; fortalecimiento de procesos administrativos; procesamiento de productos piscícolas con enfoque bioeconómico; fortalecimiento tecnológico de los sistemas productivos piscícolas en la Amazonía. Acciones que buscan optimizar su sostenibilidad y eficiencia. ABSTRACT | This research provides an overview of the freshwater fish production chain in the Ecuadorian Amazon, highlighting species such as tilapia (Oreochromis spp.), pacu (Piaractus brachymopus), paiche (Arapaima aff. gigas), sábalo (Brycon amazonicus), bocachico (Prochilodus nigricans), and Amazonian catfish (Pseudoplatystoma spp.). The study evaluates the productivity of fish farming economic units by analyzing data from the official aquaculture registry, conducting 50 surveys with producers, and 28 interviews with stakeholders. The technology used in production and processing systems, marketing channels, institutional support, human and financial resources, and research and development are also characterized. According to the data obtained, there are 2,800 producers with varying levels of production, resulting in a commercial exchange of 6 to 12 million USD. The main components of this exchange include: i) Regional supply of fish meat from aquaculture, with a range of 1,600 to 3,200 tons per year, with 95% tilapia accounting. ii) A minimum supply of 12 million fingerlings per year, with a value of at least 0.6 million USD, which are exported outside of the Amazon. iii) Purchases of artificial feed totaling 2 million USD per year, with a cost of 0.95 USD per kilogram and a feed conversion rate (FCR) of 2:1. The study identifies five main bottlenecks in the production chain: institutional, administrative, commercial, technological, and socio-environmental. To address these issues, the study proposes the following solutions: harmonization of fish culture regularization schemes, strengthening of administrative processes, processing of fish products with a bioeconomic approach, technological improvements in production systems. These actions seek to optimize its sustainability and efficiency.

Local Amazonian populations are exposed to mercury (Hg) contamination risks due to high fish consumption, a phenomenon influenced by processes of bioavailability, bioaccumulation, and biomagnification derived from natural sources or human activities. This study aimed to determine total Hg concentrations in key fish species marketed and consumed by communities in the Ecuadorian Amazon in order to propose consumption recommendations. A total of 151 fish specimens were collected from markets, collection centers, and through artisanal and sport fishers during May and June 2018, representing the minimum locally available catch. Each specimen was taxonomically identified, measured, weighed, and recorded according to collection site, and between 2 and 10 g of muscle tissue were extracted. Samples were freeze-dried and analyzed at the GET Laboratory in Toulouse, France, using direct atomic absorption spectrophotometry (Milestone® DMA-80). Twenty species belonging to eight families and three orders were identified and classified into eight trophic roles, showing diverse Hg concentration patterns according to ecological position and body size. Ninety-seven percent of catfish species (Pimelodidae), classified as carnivores and scavengers, exceeded by up to five times the maximum Hg limits recommended by the WHO and EPA-FDA for human consumption (p ≤ 0.05). Species with the lowest Hg concentrations, and therefore more suitable for consumption, were found in the upper sections of river basins, whereas greater bioaccumulation was observed in lower sections, with an inverse relationship between altitude and capture size. The study concludes that Hg contamination is present in fishery resources of the Ecuadorian Amazon, particularly in catfish species, which are under greater fishing pressure from local markets. Subsistence fishing, however, presents variable risks depending on the extraction site.