Interdependencies between Indigenous peoples, local communities, and freshwater systems in a changing Amazon

Globally, Indigenous peoples and local communities (IPs and LCs) are fighting for the recognition of their knowledge and decision-making authority in freshwater conservation. In the Amazon, decision-making around freshwater management and conservation has often overlooked Indigenous and local knowledge (ILK) and the connections between sociocultural and freshwater systems. We explored interdependencies between IPs and LCs and freshwaters in the Amazonian region through a narrative review of the academic peer-reviewed literature. The review process involved 2 phases: an initial scoping phase, which included the analysis of a large number of articles to identify main topics and develop research questions, and the review of a subset of 187 articles published from 2018 to 2022. We found that 178 studies were carried out in the Brazilian, Peruvian, and/or Bolivian Amazon, and 26 studies were conducted in other countries. A total of 60 studies focused on riverine communities and among them, 16 Indigenous groups were mentioned in 51 articles. Most studies (n = 148) emphasized the connections between water quality, fisheries, food security, health, and livelihoods. There was a paucity of studies conducted by IPs and LCs that had Indigenous or local community members among the authors. Recent studies highlighted the active role of IPs and LCs in leading community-based management efforts. We found innovative freshwater conservation and management experiences led by IPs and LCs, that effectively conserved freshwater biodiversity while promoting sustainable livelihoods. Our findings support inclusive and equitable freshwater conservation policies and practices in the Amazon and beyond, by showing the crucial role of IPs and LCs in managing and protecting freshwater resources.

Trends in Urban Wild Meat Trade of Chelonians (Turtles and Tortoises) in the Peruvian Amazon

Culturally, chelonians are important sources of nutrition and income for rural and urban people in tropical rainforests, but urban trade can cause declines in wild populations. This study analyses the urban chelonian trade and its trends to better understand the impact on free-living populations in the Northern Peruvian Amazon. We studied the urban trade of wild chelonians by conducting 526 days of participant observation and structured questionnaires with the main chelonian vendors in the wet markets of Iquitos between 2006 and 2018. The trade of chelonians decreased by -161.6%, from 22,694 individuals in 2006/07 to 8657 individuals in 2017/18. Chelonoidis denticulatus was the species sold the most (86.3%), followed by Podocnemis unifilis (13.6%). Podocnemis expansa was only sold in 2006/07. River turtle sales increased in the dry season, while sales of Chelonoidis denticulatus decreased. Turtles were the most expensive meat sold in urban markets: 49.7% more expensive than the most frequently consumed fish, Prochilodus nigricans, and 48.4% more expensive than poultry. Turtles represented only 0.19% (SD 0.23) of the index of domestic meat and fish consumption per capita. River turtle eggs are sold by a different set of vendors, and in 2017/18, 570,229 eggs were traded in the market of Belén in Iquitos, equivalent to an approximate lay of 10,418 P. unifilis and 1178 P. expansa females. The high magnitude of the trade of river turtle eggs together with the reduction in their meat trade suggests a prioritization of egg sales, which should improve the conservation of adults, since meat sales can be detrimental to chelonian populations.

Lessons learned during a 12-year monitoring project with the endangered Magdalena River turtle (Podocnemis lewyana): hunting pressure, habitat degradation, and methodological considerations

Turtle species in the Family Podocnemididae, including the Colombian endemic and critically endangered Magdalena River Turtle Podocnemis lewyana, characteristically present low recapture rates that preclude estimation of population parameters using maximum likelihood modeling. In our 12-year monitoring project with this species, we evaluated changes in relative abundances, proportions of sex/size classes, and individual body sizes and body conditions in a population in four channels in the middle Magdalena River drainage. We also inspected for associations between trends in changes in these variables and differences in hunting pressure and habitat degradation. To inspect for temporal and spatial demographic dynamics, we estimated variation in relative abundances using the Catch Per Unit Effort index, the total number of turtles captured over an entire 5-day sampling period using ten baited funnel traps. Relative abundances and the proportions of sex/size classes were different between sites and years. We found a significant decline in the proportion of females and juveniles over time, along with evidence that the females still present were smaller in body size. Our results support the hypothesis that hunting eliminates adult females from these sites, perhaps also translating into a reduction in recruitment. The lack of evidence of generalized declines in body condition of all size classes suggests that habitat degradation might contribute less to the population declines in this region. Our results also illustrate that even when recapture rates are low, monitoring turtles via standardized trapping may yield insights into the population's conservation status that other relative abundance indices cannot.

Conservation units alone are insufficient to protect Brazilian Amazonian chelonians

The creation of protected areas (PAs) is not always based on science; consequently, some aquatic species may not receive the same level of protection as terrestrial ones. The objective of this study was to identify priority areas for the conservation of chelonians in the Brazilian Amazon basin and assess the contribution of PAs, distinguishing between Full Protection Areas, Sustainable Use Areas, and Indigenous Lands for group protection. The entire species modeling procedure was carried out using Species Distribution Models. Location records were obtained from platforms such as SpeciesLink, GBIF, the Hydroatlas database, and WorldClim for bioclimatic variables adjusted with algorithms like Maximum Entropy, Random Forest, Support Vector Machine, and Gaussian-Bayesian. Indigenous lands cover more than 50% of the distribution areas of chelonian species in the Brazilian Amazon. Protected areas with higher conservation importance (Full Protection Areas and Sustainable Use Areas) hold less than 15% of the combined species distribution. Researchers face significant challenges when making decisions with models, especially in conservation efforts involving diverse taxa that differ significantly from one another within a group of individuals.