Peruvian Amazon Research Articles

Plant species richness, not hygrothermal stress, is the main predictor of gall‐inducing insect richness in Peruvian Amazon forests

AbstractPatterns of gall‐inducing insect diversity tend to be influenced by both habitat‐related and plant‐related characteristics. We investigated the distribution patterns of galling insects in four vegetation types (terra firme forest, white‐sand dry forest, white‐sand wet forest and palm swamp forest) of the Peruvian Amazon to test if the insect gall diversity (1) differs among different types of vegetation and (2) depends on host plant richness. In total, we found 11,579 galls belonging to 249 insect gall morphotypes, distributed across 30 botanical families and 75 plant species. Among host plant families, Fabaceae showed the greatest richness of insect gall morphotypes. We found that galling species richness was lower in palm swamp forest than in white‐sand forests, which can be explained by the lower richness of plants in this type of vegetation. However, we found no evidence of greater richness in xeric habitats (e.g., white‐sand dry forest) than in more mesic vegetation (terra firme forest), contradicting the hypothesis of hygrothermal stress. We also found that plant species richness was positively influenced with the richness and abundance of galling species, regardless of vegetation type. Galling insect species composition differed significantly between vegetation types, similarly to the floristic composition. Our findings show that the diversity of galling insects in the tropical rainforests of Peruvian Amazon are mainly influenced by host plant composition and host plant richness.Abstract in Spanish is available with online material.

Southernmost record of Megadolodus (Litopterna, Proterotheriidae, Megadolodinae) from the late Middle Miocene of Fitzcarrald, Peruvian Amazonia, and mesowear analysis of diet in megadolodine litopterns

ABSTRACT Megadolodinae is a clade of tropical bunodont litopterns that includes three previously recognized species from Miocene fossil sites from northern South America. Here, we report an additional occurrence of Megadolodus molariformis from the Middle Miocene exposures at the Fitzcarrald arch (Peruvian Amazonia), based on dental material, which represents the southernmost record of the clade. This discovery further increases the faunal similarity between Fitzcarrald and the coeval La Venta fauna of Colombia. Given the convergent evolution of the bunodont dentition of megadolodines with suoids (Old World pigs and New World peccaries), we tested the hypothesis of frugivory in megadolodines with a mesowear angle approach using modern pigs and peccaries. These analyses differentiate the diet of modern suoids and suggest that megadolodines had a more abrasive diet than most of these taxa, except for the grazing warthogs. The dentition of megadolodines shows similar levels of abrasion to modern babirusas, thereby suggesting that the latter may represent an appropriate modern analog.

Hydrogeomorphic Characterization of the Huallaga River for the Peruvian Amazon Waterway

Hydrogeomorphic Characterization of the Huallaga River for the Peruvian Amazon Waterway

SUSTAINABLE MODULAR PROTOTYPE WITH BAMBOO FOR COMMUNITY CENTERS

This contribution presents the results of research carried out in two areas of the Peruvian Amazon within the framework of two community projects for technology transfer and capacity development in construction with bamboo, with the objective of designing and building a modular prototype with bamboo for 1/1 scale with the function of a community center, capable of incorporating sustainable strategies, replicability and adaptability, as an architectural alternative to the deterioration of the Amazonian natural and cultural habitat. The methodology contemplates two phases of experimentation, the first of design and construction of the Model Prototype in the Southwest Amazon (Pilcopata), studying the local context, the bamboo species, the participatory construction process, to formulate the modular proposal with the function of a Center Tourist Community; the second validation of the Prototype, identifying the bamboo species and adding a module in the design format for use in the Communal Transformation Center in the Central Amazon (Native Community of Pampa Michi), both executed with the local population. Among the results, the efficiency, practicality and flexibility of the design and construction stand out, and the verification of sustainable strategies, with the use of carbon neutral materials such as bamboo, the revaluation of traditional knowledge with palm leaves and the replicability in similar conditions with models of participatory learning, which validate the Prototype. In a third phase, the construction processes are systematized, being part of the Manual for the construction of light structures with bamboo in Peru.

Possible Spreading of SARS-CoV-2 from Humans to Captive Non-Human Primates in the Peruvian Amazon.

Human-to-animal transmission events of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) have been reported in both domestic and wild species worldwide. Despite the high rates of contagion and mortality during the COVID-19 (Coronavirus Diseases 2019) pandemic in Peru, no instances of natural virus infection have been documented in wild animals, particularly in the Amazonian regions where human-wildlife interactions are prevalent. In this study, we conducted a surveillance investigation using viral RNA sequencing of fecal samples collected from 76 captive and semi-captive non-human primates (NHPs) in the Loreto, Ucayali, and Madre de Dios regions between August 2022 and February 2023. We detected a segment of the RNA-dependent RNA polymerase (RdRp) gene of SARS-CoV-2 by metagenomic sequencing in a pooled fecal sample from captive white-fronted capuchins (Cebus unicolor) at a rescue center in Bello Horizonte, Ucayali. Phylogenetic analysis further confirmed that the retrieved partial sequence of the RdRp gene matched the SARS-CoV-2 genome. This study represents the first documented instance of molecular SARS-CoV-2 detection in NHPs in the Peruvian Amazon, underscoring the adverse impact of anthropic activities on the human-NHP interface and emphasizing the importance of ongoing surveillance for early detection and prediction of future emergence of new SARS-CoV-2 variants in animals.

Elevated mercury exposure in bird communities inhabiting Artisanal and Small-Scale Gold Mining landscapes of the southeastern Peruvian Amazon.

Artisanal and Small-Scale Gold Mining (ASGM) represents a significant source of anthropogenic mercury emissions to the environment, with potentially severe implications for avian biodiversity. In the Madre de Dios department of the southern Peruvian Amazon, ASGM activities have created landscapes marred by deforestation and post-mining water bodies (mining ponds) with notable methylation potential. While data on Hg contamination in terrestrial wildlife remains limited, this study measures Hg exposure in several terrestrial bird species as bioindicators. Total Hg (THg) levels in feathers from birds near water bodies, including mining ponds associated with ASGM areas and oxbow lakes, were analyzed. Our results showed significantly higher Hg concentrations in birds from ASGM sites with mean ± SD of 3.14 ± 7.97 µg/g (range: 0.27 to 72.75 µg/g, n = 312) compared to control sites with a mean of 0.47 ± 0.42 µg/g (range: 0.04 to 1.89 µg/g, n = 52). Factors such as trophic guilds, ASGM presence, and water body area significantly influenced feather Hg concentrations. Notably, piscivorous birds exhibited the highest Hg concentration (31.03 ± 25.25 µg/g, n = 12) exceeding known concentrations that affect reproductive success, where one measurement of Chloroceryle americana (Green kingfisher; 72.7 µg/g) is among the highest ever reported in South America. This research quantifies Hg exposure in avian communities in Amazonian regions affected by ASGM, highlighting potential risks to regional bird populations.

Assessment of Information Literacy Competences in Peruvian University Students: An Exploratory Study

The objective was to evaluate the perception of the informational literacy competences of the university students of the Peruvian Amazon. The investigation was developed under a quantitative approach, the design was non-experimental and cross-sectional descriptive type. The sample was made up of 707 students to whom the Informational Literacy Competences Questionnaire was given, an instrument with an adequate level of content validity and reliability. According to the results, the level of development of the informational literacy competencies of 37.5% of students was low, 35% was medium, and 27.5% was high. Likewise, the dimensions of information retrieval, information assessment and information processing were also valued at a low level. However, the information communication dimension of information was valued at a medium level. On the other hand, it was found that the level of informational literacy competences was significantly associated with the year of study in which the students were (p<0.05). It was concluded that the level of development of the informational literacy competencies that characterized the students was low.

Correction: A multiple linear regression model for the prediction of summer rainfall in the northwestern Peruvian Amazon using large-scale indices

Correction: A multiple linear regression model for the prediction of summer rainfall in the northwestern Peruvian Amazon using large-scale indices

Malaria seroepidemiology in very low transmission settings in the Peruvian Amazon

Despite progress towards malaria reduction in Peru, measuring exposure in low transmission areas is crucial for achieving elimination. This study focuses on two very low transmission areas in Loreto (Peruvian Amazon) and aims to determine the relationship between malaria exposure and proximity to health facilities. Individual data was collected from 38 villages in Indiana and Belen, including geo-referenced households and blood samples for microscopy, PCR and serological analysis. A segmented linear regression model identified significant changes in seropositivity trends among different age groups. Local Getis-Ord Gi* statistic revealed clusters of households with high (hotspots) or low (coldspots) seropositivity rates. Findings from 4000 individuals showed a seropositivity level of 2.5% (95%CI: 2.0%-3.0%) for P. falciparum and 7.8% (95%CI: 7.0%-8.7%) for P. vivax, indicating recent or historical exposure. The segmented regression showed exposure reductions in the 40–50 age group (β1 = 0.043, p = 0.003) for P. vivax and the 50–60 age group (β1 = 0.005, p = 0.010) for P. falciparum. Long and extreme distance villages from Regional Hospital of Loreto exhibited higher malaria exposure compared to proximate and medium distance villages (p < 0.001). This study showed the seropositivity of malaria in two very low transmission areas and confirmed the spatial pattern of hotspots as villages become more distant.

Disentangling shade effects for cacao pest and disease regulation in the Peruvian Amazonia

Disentangling shade effects for cacao pest and disease regulation in the Peruvian Amazonia

Characterization and phylogenetic analysis of the complete plastid genome of Theobroma bicolor (Malvaceae) from Peru

Theobroma bicolor Bonpl. 1806 is distributed in the Neotropics from southern Mexico to the Peruvian and Brazilian Amazon. High-throughput sequencing of T. bicolor from Peru (KUELAP2926) resulted in the assembly of its complete plastid genome (GenBank accession number OQ557154). The chloroplast genome of T. bicolor is A + T-rich (62.97%), having 160,317 bp in size and containing 130 genes; including a pair of inverted repeat regions (IRs) of 25,462 bp separated by a large single copy region (LSC) of 89,221 bp and a small single copy region (SSC) of 20,172 bp. This plastid genome is similar in length, content, and organization to other members of the genus Theobroma. Phylogenetic analyses of T. bicolor support its sistership to the clade comprising T. cacao and T. grandiflorum. This study may contribute valuable information to the phylogenetic relationships within the genus Theobroma.

Training with a psychosocial health neurolearning approach in Peruvian professionals with health insurance: Experimental study.

Psychosocial risk factors as determinants of health at work can affect both the physical and psychological well-being of the worker. Training systems that include cognitive-preventive content work best when knowledge construction is based on neurolearning. The purpose of this study was to compare the degree of content processing with the insertion of deterrent (group A) versus persuasive sentences (group B) as an effect of a training with a neurolearning approach to psychosocial health in the work of a group of professionals with health insurance in the Peruvian Amazon. Experimental design with pre-/post-test, including two experimental groups plus a control group, n = 48 subjects in total and 16 per group, aged 22-36 years. The training took place between December 2018 and January 2019 with a duration of 18 hours spaced over six weeks. A register previously validated by five experts was used for data collection. The distribution of data in the groups was adequate in both pre-test and post-test, except in post-test in group "B" (p = 0.002). In the control group, the results of content processing in both pre-test and post-test remained similar (p = 0.667). The processing of psychosocial occupational health content in the post-test was significantly different between the intervention and control groups (p = 0.001), distinguishing the processing of content with the insertion of deterrent phrases. The results indicate that training with a neurolearning approach can improve the processing of content with the insertion of deterrent phrases for compliance with regulations aimed at promoting psychosocial health at work.

Soil characteristics and allometric models for biometric characteristics and nutrient amounts for high yielding “Bolaina” (Guazuma crinita) trees

The Peruvian amazon is very diverse in native forestry species, the Guazuma crinita “Bolaina” being one of the most planted species in the country; however, little or no information about soil requirements and nutrient demands is known. The objective of this work was to assess the general conditions of soil fertility, biomass and macro- and micronutrient amounts in high-productivity Guazuma crinita plantations. Fields of high yielding Bolaina of different ages (1–10 years) were sampled in two regions. Soil and plant samples were collected in each field and biometric measurements of fresh weight, diameter at breast height and height were performed. For soil and plant analysis, both macro- (N, P, K, Ca, Mg, S) and micronutrients (B, Cu, Fe, Mn, Zn) were determined. Finally, allometric equations were constructed for biometric and nutrient amounts. This study is the first to assess and model macro- and micronutrient amounts in the productive cycle in this species, which grows in fertile soils. In the case of biometric equations, the logarithmic and logistic models performed better. For nutrient amounts, this species followed a pattern of Ca > N > K > P > S > Mg for macronutrients and Fe > B > Mn > Zn > Cu for micronutrients. The best prediction models for nutrients were the square root and logistic models.

Two new species of dactylogyrids (Monogenea: Dactylogyridae) infecting the gill filaments of fishes in the southern Peruvian Amazon.

Two new dactylogyrid species were found infecting the gill filaments of two freshwater fishes collected in the Amazon River basin around Madre de Dios, Peru, namely, Demidospermus wilveri n. sp. from Loricaria sp. (Siluriformes: Loricariidae), and Notozothecium agusti n. sp. from Brycon amazonicus (Spix & Agassiz) (Characiformes: Bryconidae). Demidospermus wilveri n. sp. is characterized by having the following combination of characteristics: (1) a male copulatory organ (MCO) with 1½ rings and a spoon-shaped distal end, (2) an accessory piece with expanded distal end, (3) dorsal and ventral bars with broadly V-shaped and expanded ends, and (4) hooks similar in size. Notozothecium agusti n. sp. differs from its ten congeners by the following combination of characteristics: (1) a coiled MCO with 1½ rings and a sinuous accessory piece with kidney-shaped distal end, (2) an rod-shaped and straight dorsal bar, (3) and anchors with robust superficial roots. Demidospermus wilveri n. sp. represents the thirty-second species in the genus, the eighth from Peru and the fifth parasitising a loricariid catfish from the Peruvian Amazon. Notozothecium agusti n. sp. is the second species of the genus described in Peru and the first species infecting a bryconid host.

Two new species of genus Agrilus Curtis, 1825 (Coleoptera: Buprestidae: Agrilinae) from the Peruvian Amazon Rainforest

Two new species of genus Agrilus Curtis, 1825 are described from Peru: Agrilus (Agrilus) huggerti sp. nov. and Agrilus (Agrilus) satipo sp. nov., based on specimens collected from the Peruvian amazon rainforest, an important ecosystem of the tropical jungle in South America.

Perceptions and reality in fisher coexistence with aquatic predators in the Peruvian Amazon

AbstractHumans and large aquatic predators compete for fish and negative interactions are widely reported as ‘human–wildlife conflicts’. When aquatic predators are perceived to damage fisheries or fishing equipment, lethal control can occur. The perceptions and reality of damage are infrequently compared, but this relationship is key to determining how negative outcomes can be mitigated. We examine coexistence between people and six large aquatic piscivores (two caiman, two dolphins, two otters) in Amazonian Peru. We determine the extent of damage to fishing equipment caused by each species and compare this to the amount of damage perceived by fishers. Giant otter populations have recently recovered in some areas, so we expected different perceptions relating to experiences with otters. We trained fishers to complete fishing registers (n = 278, 1173 h of fishing) to record damage to nets by wildlife. We interviewed 302 people from three sites to determine perceptions of damage by predators, and attitudes towards giant otters. Rates of damage to nets reflected the presence and populations of different aquatic predators at each site, but when present, dolphins and caimans damaged nets more than otters, which rarely damaged nets. People living where giant otters had recently recovered perceived higher relative levels of damage to nets by them and had more negative attitudes about them, compared to people from areas where giant otters had been present for longer, aquatic predators were more abundant, and community resource management was longer‐established. Better knowledge and more experience with a species may lead to more accurate perceptions of damage and increased tolerance. Where humans and animals compete for natural resources, conflict mitigation rarely includes better resource management. If tolerance of predators is greater where predators are common, and resources have not been overexploited, resource management may yield greater gains for stakeholders than other commonly prescribed forms of mitigation.

‘You have a lot of mirrors’: structural and socioecological factors impacting adolescent pregnancy and reproductive health in the Amazon basin, Peru, a qualitative study

Loreto, in the Peruvian Amazon, has one of the highest adolescent pregnancy rates in the country. However, underlying causes of adolescent pregnancy are not fully understood as data are limited in Indigenous and remote Amazonian communities. This study investigated adolescent reproductive health within Loreto using an ecological systems framework. Forty-one semi-structured interviews were conducted in June 2022: community leaders (n = 12) and adolescent participants between 15 and 17 years of age (pregnant girls, n = 11; never pregnant girls, n = 9; and boys, n = 9). We also conducted focus group discussions with community health workers and educators in October 2022 (three focus groups, n = 15). Adolescent reproductive health is complex with multi-layered factors that put girls at higher risk of pregnancy. We found a paradoxical relationship between expected social and gender norms and individual desires. This research provides a contextual understanding of the lived experience of adolescents and young people in the Amazon region of Peru. Our findings suggest the need for greater exploration of the contradictory ideas surrounding adolescent pregnancy and female sexuality.

Between Co‐Management and Responsibilisation: Comparative Perspectives from Two Reservas Comunales in the Peruvian Amazon

Peru introduced co‐managed Reservas Comunales (Communal Reserves) as an alternative to the ‘fortress conservation’ approach that characterises other protected areas where Indigenous Peoples tend to be excluded from both the physical space and managerial aspects of conservation regimes. Although these Reserves are lauded internationally as supporting Indigenous Peoples' self‐determination, this article examines the challenges that arise from the cogestión (co‐management) regime for Indigenous organisations and communities. Focusing on the ‘responsibilisation’ relationships created in the co‐management of two Communal Reserves, the article reflects on the different trajectories of this transfer of responsibilities, and the processes through which Indigenous co‐management organisations are expected to adopt the government's conservation goals.

Phylogenetic congruence of Plasmodium spp. and wild ungulate hosts in the Peruvian Amazon

Malaria parasites are known to infect a variety of vertebrate hosts, including ungulates. However, ungulates of Amazonia have not been investigated. We report for the first time, the presence of parasite lineages closely related to Plasmodium odocoilei clade 1 and clade 2 in free-ranging South American red-brocket deer (Mazama americana; 44.4%, 4/9) and gray-brocket deer (Mazama nemorivaga; 50.0%, 1/2). We performed PCR-based analysis of blood samples from 47 ungulates of five different species collected during subsistence hunting by an indigenous community in the Peruvian Amazon. We detected Plasmodium malariae/brasilianum lineage in a sample from red-brocket deer. However, no parasite DNA was detected in collared peccary (Pecari tajacu; 0.0%, 0/10), white-lipped peccary (Tayassu pecari; 0.0%, 0/15), and tapir (Tapirus terrestris; 0.0%, 0/11). Concordant phylogenetic analyses suggested a possible co-evolutionary relationship between the Plasmodium lineages found in American deer and their hosts.

Genomic insights into ESBL-producing Escherichia coli isolated from non-human primates in the Peruvian Amazon.

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are on the WHO priority pathogens list because they are associated with high mortality, health-care burden, and antimicrobial resistance (AMR), a serious problem that threatens global public health and should be addressed through the One Health approach. Non-human primates (NHP) have a high risk of acquiring these antibiotic-resistant bacteria due to their close phylogenetic relationship with humans and increased anthropogenic activities in their natural environments. This study aimed to detect and analyze the genomes of ESBL-producing Escherichia coli (ESBL-producing E. coli) in NHP from the Peruvian Amazon. We collected a total of 119 fecal samples from semi-captive Saguinus labiatus, Saguinus mystax, and Saimiri boliviensis, and captive Ateles chamek, Cebus unicolor, Lagothrix lagothricha, and Sapajus apella in the Loreto and Ucayali regions, respectively. Subsequently, we isolated and identified E. coli strains by microbiological methods, detected ESBL-producing E. coli through antimicrobial susceptibility tests following CLSI guidelines, and analyzed their genomes using previously described genomic methods. We detected that 7.07% (7/99) of E. coli strains: 5.45% (3/55) from Loreto and 9.09% (4/44) from Ucayali, expressed ESBL phenotype. Genomic analysis revealed the presence of high-risk pandemic clones, such as ST10 and ST117, carrying a broad resistome to relevant antibiotics, including three blaCTX-M variants: blaCTX-M-15, blaCTX-M-55, and blaCTX-M-65. Phylogenomic analysis confirmed the clonal relatedness of high-risk lineages circulating at the human-NHP interface. Additionally, two ESBL-producing E. coli strains were identified as EPEC (eae) and ExPEC according to their virulence profiles, and one more presented a hypermucoviscous phenotype. We report the detection and genomic analysis of seven ESBL-producing E. coli strains carrying broad resistome and virulence factors in NHP from two regions of the Peruvian Amazon. Some of these strains are closely related to high-risk pandemic lineages previously reported in humans and domestic animals, highlighting the negative impact of anthropogenic activities on Amazonian wildlife. To our knowledge, this is the first documentation of ESBL-producing E. coli in NHP from the Amazon, underscoring the importance of adopting the One Health approach to AMR surveillance and minimizing the potential transmission risk of antibiotic-resistant bacteria at the human-NHP interface.