Evaluating Thermal Infrared Drone Flight Parameters on Spider Monkey Detection in Tropical Forests.

Geoffroy's spider monkeys, an endangered, fast-moving arboreal primate species with a large home range and a high degree of fission-fusion dynamics, are challenging to survey in their natural habitats. Our objective was to evaluate how different flight parameters affect the detectability of spider monkeys in videos recorded by a drone equipped with a thermal infrared camera and examine the level of agreement between coders. We used generalized linear mixed models to evaluate the impact of flight speed (2, 4, 6 m/s), flight height (40, 50 m above ground level), and camera angle (-45°, -90°) on spider monkey counts in a closed-canopy forest in the Yucatan Peninsula, Mexico. Our results indicate that none of the three flight parameters affected the number of detected spider monkeys. Agreement between coders was "substantial" (Fleiss' kappa coefficient = 0.61-0.80) in most cases for high thermal-contrast zones. Our study contributes to the development of standardized flight protocols, which are essential to obtain accurate data on the presence and abundance of wild populations. Based on our results, we recommend performing drone surveys for spider monkeys and other medium-sized arboreal mammals with a small commercial drone at a 4 m/s speed, 15 m above canopy height, and with a -90° camera angle. However, these recommendations may vary depending on the size and noise level produced by the drone model.

Increased capture efficiency of Scolytinae with modified semi-funnel trap model / Aumento da eficiência de captura de Scolytinae com armadilha modelo semifunil modificada

Scolytinae species that, in high populations, can damage reducing wood production in forest crops. These beetles are monitored with traps baited with ethanol and increasing their efficiency can improve the integrated management of these insects. The objective was to evaluate the increase in the capture efficiency of Scolytinae with a semi-funnel trap model, in two experiments, one including wooden elements and other increasing the flight interception area and to correlate the numbers of these beetles collected with climatic factors. In the experiment 1, Eucalyptus urophylla S. T. Blake slats were directly attached to the collector flask and in another treatment, in addition to these slats, Cedrela sp. strips were inserted inside the bait holding hose. In the experiment 2, the insect interception area in the trap, originally 480 cm2, was expanded to 1,200 cm2 and compared with the model Pet-Santa Maria trap with an interception area of 550 cm2. Weekly collections were carried out between May 2018 and June 2019. The beetles collected were taken to the Wood Biodeterioration Laboratory of the Federal Rural University of Rio de Janeiro (UFRRJ) where they were sorted, identified at family level, counted and their number correlated with climatic factors. Statistical analyzes of the collected data were processed by the BioStat® 5.3 program. In the experiment 1 were collected 869 Scolytinae. The numbers of beetles collected per trap without modification, with E. urophylla slats and E. urophylla slats + Cedrela sp. strips were similar, 7.3 ± 3.8, 7.8 ± 6.2 and 7.7 ± 5.0 respectively. In the experiment 2 were collected 4,398 Scolytinae. Increasing the interception area of the beetles increased the efficiency of the semi-funnel trap, with 42.7 ± 20.5 Scolytinae collected compared to the original semi-funnel trap, 28.6 ± 12.6 and the Pet-Santa Maria, 20.4 ± 10.4, per trap. The number of Scolytinae did not correlate with climatic factors in the experiment 1 and it was correlated with temperature, relative humidity and wind speed, but not with precipitation, in the 2. The incorporation of E. urophylla slats or Cedrela sp. strips in the semi-funnel trap did not increase the number of beetles collected, but, the increase in the flight interception area and the temperature, relative humidity and wind speed were correlated with the number of beetles collected.

Espécies de besouros Scolytinae, em altas populações, podem danificar a madeira e reduzir a produtividade de cultivos florestais. Esses besouros são monitorados com armadilhas iscadas com etanol e o aumento da eficiência das mesmas pode melhorar o manejo integrado desses insetos. O objetivo foi avaliar o aumento da eficiência de captura de Scolytinae com armadilha modelo semifunil, em dois experimentos, um incluindo elementos de madeira e outro aumentando a área de interceptação de voo e correlacionar o número desses besouros coletados com fatores climáticos. No experimento 1, ripas de Eucalyptus urophylla S. T. Blake foram fixadas, diretamente, no frasco coletor e em outro tratamento, além dessas ripas, fitas de Cedrela sp. foram inseridas no interior da mangueira porta isca. No experimento 2, a área de interceptação de insetos na armadilha, originalmente, com 480 cm2, foi ampliada para 1200 cm2 e comparada com a armadilha modelo Pet-Santa Maria com área de interceptação de 550 cm2. Coletas semanais foram realizadas entre maio de 2018 a junho de 2019. Os insetos capturados foram levados ao Laboratório de Biodeterioração da Madeira da Universidade Federal Rural do Rio de Janeiro (UFRRJ) onde foram triados, identificados em nível de família, contados e a abundância correlacionada com fatores climáticos. As análises estatísticas dos dados coletados foram processadas pelo programa BioStat® 5.3. No experimento 1 foram coletados 869 Scolytinae. Os números de besouros coletados por armadilha sem modificação, com ripas de E. urophylla e com ripas de E. urophylla + fita de Cedrela sp. foram semelhantes, 7,3 ± 3,8; 7,8 ± 6,2 e 7,7 ± 5,0 respectivamente. No experimento 2 foram coletados 4398 Scolytinae. O aumento da área de interceptação dos besouros aumentou a eficiência da armadilha semifunil, com 42,7 ± 20,5 Scolytinae coletados por armadilha comparado a semifunil original, 28,6 ± 12,6 e a Pet-Santa Maria, 20,4 ± 10,4. O número de Scolytinae não se correlacionou com os fatores climáticos no experimento 1 e se correlacionou com a temperatura, umidade relativa e velocidade do vento, mas não com a precipitação, no 2. A incorporação de ripas de E. urophylla ou fitas de Cedrela sp. na armadilha semifunil não aumentou o número de besouros coletados, mas, o aumento da área de intercepção de voo e a temperatura, umidade relativa do ar e velocidade do vento se correlacionaram com o número de besouros coletados.

Using species distribution modeling to generate relative abundance information in socio-politically unstable territories: Conservation of Felidae in the central-western region of Mexico.

The distribution range and population abundance of species provide fundamental information on the species-habitat relationship required for management and conservation. Abundance inherently provides more information about the ecology of species than do occurrence data. However, information on abundance is scarce for most species, mainly at large spatial scales. The objective of this work was, therefore, to provide information regarding the population status of six wild felids inhabiting territories in Mexico that are inaccessible or politically unstable. This was done using species distribution models derived from occurrence data. We used distribution data at a continental scale for the wild felids inhabiting Mexico: jaguar (Panthera onca), bobcat (Lynx rufus), ocelot (Leopardus pardalis), cougar (Puma concolor), margay (Leopardus wiedii), and jaguarundi (Herpailurus yagouaroundi) to predict environmental suitability (estimated by both Maxent and the distance to niche centroid, DNC). Suitability was then examined by relating to a capture rate-based index, in a well-monitored area in central western Mexico in order to assess their performance as proxies of relative abundance. Our results indicate that the environmental suitability patterns predicted by both algorithms were comparable. However, the strength of the relationship between the suitability and relative abundance of local populations differed across species and between algorithms, with the bobcat and DNC, respectively, having the best fit, although the relationship was not consistent in all the models. This paper presents the potential of implementing species distribution models in order to predict the relative abundance of wild felids in Mexico and offers guidance for the proper interpretation of the relationship between suitability and population abundance. The results obtained provide a robust information base on which to outline specific conservation actions and on which to examine the potential status of endangered species inhabiting remote or politically unstable territories in which on-field monitoring programs are not feasible.

Hematological parameters of a Neotropical wild frog population, with a phylogenetic perspective on blood cell composition in Anura.

Hematological parameters can provide key information to an animal health status. However, this information is usually hard to obtain. Here, we described the hematological parameters of Leptodactylus podicipinus in the Brazilian Pantanal. We measured red blood cell morphometrics, erythrogram, and leukogram. We also tested for phylogenetic signal in the erythrogram and leukogram of 48 frog species from 15 families, testing if body size explains their variation. Lymphocytes were the most abundant leukocytes (>60%) in L. podicipinus, followed by neutrophils (∼10%). Given that L. podicipinus is an abundant and widely distributed species in central Brazil, knowing its hematological pattern can help establish a baseline and improve its use as a bioindicator of environmental degradation. Mean corpuscular hemoglobin and value contributed more to the phylomorphospace of erythrogram, in which Leptodactylus spp. and Hypsiboas raniceps had lower values of these variables, whereas Bufotes viridis and Hyla arborea had high values. The phylogenetic signal was spread throughout the dimensions of the leukogram phylomorphospace. The variables that most contributed to it were total leukocytes counts, lymphocytes, and neutrophils. We also found a moderate phylogenetic signal for both the erythrogram and leukogram. Accordingly, body size accounted for a low proportion of variation in both the leukogram (4.7%) and erythrogram (0.57%). By applying phylogenetic comparative methods to hematological parameters, our results add a new perspective on the evolution of blood cell physiology in frogs.

Density and habitat use of one of the last jaguar populations of the Brazilian Atlantic Forest: Is there still hope?

The jaguar (Panthera onca) plays an important role in maintaining biodiversity and ecological processes. We evaluated the status of a jaguar population in one of the last stronghold habitats for its conservation in the Atlantic Forest, the Rio Doce State Park (RDSP). We used a random survey design from 2016/17 to estimate jaguar abundance and density as well as its occupancy and detection probabilities in the entire Park's area. To monitor for temporal fluctuations in density and abundance, we used a systematic survey design in the southern portion of the Park where jaguars were more recorded when using the random approach. We then conducted two surveys in 2017/18 and 2020. Our 2016/17 random survey revealed that jaguar density (0.11 ± SE 0.28 individuals/100 km2) was the lowest obtained for the species across the Atlantic Forest. We noticed that jaguar density increased three times from 2017/18 (0.55 ± SE 0.45 individuals/100 km2) to 2020 (1.61 ± SE 0.6 individuals/100 km2). Jaguar occupancy and detection probability were 0.40 and 0.08, respectively. The low jaguar occupancy probability was positively associated with smaller distances from lakes and records of potential prey. The detection probability was positively associated with prey detection, the rainy season, and smaller distances from lakes. Our work contributes to a growing awareness of the potential conservation value of a protected area in a human-dominated landscape as one of the last strongholds for jaguars across the Atlantic Forest.

Efficacy of Hair Total Mercury Content as a Biomarker of Methylmercury Exposure to Communities in the Area of Artisanal and Small-Scale Gold Mining in Madre de Dios, Peru.

Total mercury content (THg) in hair is an accepted biomarker for chronic dietary methylmercury (MeHg) exposure. In artisanal and small-scale gold mining (ASGM) communities, the validity of this biomarker is questioned because of the potential for contamination from inorganic mercury. As mining communities may have both inorganic and organic mercury exposures, the efficacy of the hair-THg biomarker needs to be evaluated, particularly as nations begin population exposure assessments under their commitments to the Minamata Convention. We sought to validate the efficacy of hair THg for public health monitoring of MeHg exposures for populations living in ASGM communities. We quantified both THg and MeHg contents in hair from a representative subset of participants (N = 287) in a large, population-level mercury exposure assessment in the ASGM region in Madre de Dios (MDD), Peru. We compared population MeHg-THg correlations and %MeHg values with demographic variables including community location, sex, occupation, and nativity. We observed that hair MeHg-THg correlations were high (r > 0.7) for all communities, regardless of location or nativity. Specifically, for individuals within ASGM communities, 81% (121 of 150 total) had hair THg predominantly in the form of MeHg (i.e., >66% of THg) and reflective of dietary exposure to mercury. Furthermore, for individuals with hair THg exceeding the U.S. EPA threshold (1.0 µg/g), 88 out of 106 (83%) had MeHg as the predominant form. As a result, had urine THg solely been used for mercury exposure monitoring, approximately 59% of the ASGM population would have been misclassified as having low mercury exposure. Our results support the use of hair THg for monitoring of MeHg exposure of populations in ASGM settings where alternative biomarkers of MeHg exposure are not feasible.

New records of the critically endangered Ecuadorian white-fronted capuchin (Cebus aequatorialis) detected by remote cameras.

The Ecuadorian white-fronted capuchin (Cebus aequatorialis) is classified as Critically Endangered (CR) on the IUCN Red List at both international and national levels in Ecuador, and the majority of detections have been recorded from direct observation. In this work, we report the occurrence of this species in a new location in the Coastal Region of Ecuador recorded by remote cameras. Overall, eight separate detections were recorded by three unique cameras from 19 Aug to 10 Dec 2016, over seven individual days, with a detection rate of 1.4 records per 1000 camera days. One additional detection was recorded in a brief remote camera survey conducted in January and February 2018. Only two direct observations were recorded in many visits to the study area over the past several years, suggesting that the use of remote cameras could be an effective method to detect the occurrence of Ecuadorian white-fronted capuchin, particularly in tropical dry forests with low tree coverage.

Estado poblacional del cucarachero de pantano, Cistothorus apolinari (Passeriformes: Troglodytidae) en siete humedales de la Sabana de Bogotá, Colombia

Introduction: The Apolinar's Wren Cisthotorus apolinari is an endemic species of the Eastern Andes of Colombia currently classified as Critically Endangered (CR) at the national level and Endangered (EN) worldwide, mainly due to the degradation of wetlands, their primary habitat, and the parasitism of the nests. Objetive: Evaluate the state of the populations of C. apolinari in seven wetlands of the Sabana de Bogotá, searching to define what the areas evaluated mean that it hosts the largest population of the species and what other factors determine these population sizes. Methods Between July and December 2014 in seven wetlands we monitoring carried out using counting points and auditory censuses, the abundance of the Apolinar's Wren was recorded, the vegetation cover where the individuals were recorded and the abundances of Shiny Cowbird Molothrus bonariensis. Results: There were 63.6 h of observation and 88 counting points, obtain a nine records of C. apolinari , one individual in Tibanica, three in La Florida and five in Gualí, mainly associated with the reed Schoenoplectus californicus. None of the biotic and abiotic factors evaluated in the wetlands, were found to determine the presence of the Apolinar's Wren, but trends were present for some variables as the presence of S. californicus and Thypa spp. Conclusions: The population of C. apolinari has had a significant reduction of up to 94 %, added to a possible local extinction in the wetland of La Conejera. These results seek to provide relevant information to contribute to the formulation of effective conservation measures for the protection of the species and its habitat throughout its distribution in the country.

Attractive lures for fruit flies in an organic guava orchard / Iscas atrativas para a mosca-das-frutas em um pomar orgânico de goiaba

Fruit flies are the biggest obstacle in guava cultivation, with the monitoring of population a fundamental aspect for their management. The objective of this study was to assess the effectiveness of attractive lures for fruit flies in guava trees, produced in an organic system. McPhail traps were installed with 400 mL of solution, in four repetitions, and distributed in randomized blocks in six treatments: Isca Mosca® (5%); Isca Samaritá Tradicional® (5%); Torula® yeast; Bio Anastrepha® (5%); Ceratrap® and guava juice (50%), with 3 weekly reviews. Data on capture were subjected to analysis of variance, and averages were compared (Tukey 5%). The values of fly trap per day (FTD) were computed. The correlation between flies and meteorological variables were evaluated, as well as the monthly cost of lures. A total of 37,917 individuals from the genus Anastrepha and 122 species of flies Ceratitis capitata were collected, being Anastrepha spp. the main genus of fruit fly in the region. The Ceratrap product proved to be superior, followed by Torula, Isca Mosca, and Bio Anastrepha; Isca Samaritá and guava juice presented the lowest results. The standard trapping of females was like the total. The uniformity of attraction presented a drop in all treatments, and Ceratrap was more constant after seven days. The correlations between meteorological factors and population variation were positive and significant only for precipitation. The most expensive treatments (Ceratrap and Torula) were also the most efficient and selective, and the Ceratrap product required less manpower.(AU)

A presença de mosca-das-frutas é o maior obstáculo à produção de goiabas, sendo o monitoramento populacional de fundamental importância para seu manejo. O objetivo deste trabalho foi avaliar a eficácia de iscas atrativas para mosca-das-frutas em goiabeiras, produzidas em um sistema orgânico. Foram instaladas armadilhas McPhail contendo 400 mL de solução, em quatro repetições e distribuição em blocos randomizados, em seis tratamentos: isca Mosca® (5%); isca Samaritá Tradicional® (5%); levedura Torula®; Bio Anastrepha® (5%); Ceratrap® e suco de goiaba (50%), com 3 avaliações semanais. Os dados da captura foram submetidos à análise de variância e às médias comparadas (Tukey 5%). Os valores de Mosca por Armadilha por Dia (MAD) foram calculados. A correlação entre moscas e as variáveis meteorológicas foi avaliada e o custo mensal das iscas foi calculado. Foram coletados 37.917 indivíduos do gênero Anastrepha e 122 moscas da espécie Ceratitis capitata, sendo a Anastrepha spp. o principal gênero de mosca-das-frutas da região. O produto Ceratrap mostrou-se superior, seguido pelas iscas Torula, Isca Mosca e Bio Anastrepha; a Isca Samaritá e o suco de goiaba apresentaram os menores resultados de captura. O padrão de captura de fêmeas foi semelhante ao total. Verificou-se uma queda na uniformidade de atração de todos os tratamentos, sendo o Ceratrap o que apresentou maior constância após sete dias. As correlações entre os fatores meteorológicos e a flutuação populacional foram positivas e significativas apenas para a precipitação. Os tratamentos mais onerosos (Ceratrap e Torula) também foram os mais eficientes e seletivos, sendo o produto Ceratrap o que demandou menor mão de obra.(AU)

Attractive lures for fruit flies in an organic guava orchard / Iscas atrativas para a mosca-das-frutas em um pomar orgânico de goiaba

Fruit flies are the biggest obstacle in guava cultivation, with the monitoring of population a fundamental aspect for their management. The objective of this study was to assess the effectiveness of attractive lures for fruit flies in guava trees, produced in an organic system. McPhail traps were installed with 400 mL of solution, in four repetitions, and distributed in randomized blocks in six treatments: Isca Mosca® (5%); Isca Samaritá Tradicional® (5%); Torula® yeast; Bio Anastrepha® (5%); Ceratrap® and guava juice (50%), with 3 weekly reviews. Data on capture were subjected to analysis of variance, and averages were compared (Tukey 5%). The values of fly trap per day (FTD) were computed. The correlation between flies and meteorological variables were evaluated, as well as the monthly cost of lures. A total of 37,917 individuals from the genus Anastrepha and 122 species of flies Ceratitis capitata were collected, being Anastrepha spp. the main genus of fruit fly in the region. The Ceratrap product proved to be superior, followed by Torula, Isca Mosca, and Bio Anastrepha; Isca Samaritá and guava juice presented the lowest results. The standard trapping of females was like the total. The uniformity of attraction presented a drop in all treatments, and Ceratrap was more constant after seven days. The correlations between meteorological factors and population variation were positive and significant only for precipitation. The most expensive treatments (Ceratrap and Torula) were also the most efficient and selective, and the Ceratrap product required less manpower.(AU)

A presença de mosca-das-frutas é o maior obstáculo à produção de goiabas, sendo o monitoramento populacional de fundamental importância para seu manejo. O objetivo deste trabalho foi avaliar a eficácia de iscas atrativas para mosca-das-frutas em goiabeiras, produzidas em um sistema orgânico. Foram instaladas armadilhas McPhail contendo 400 mL de solução, em quatro repetições e distribuição em blocos randomizados, em seis tratamentos: isca Mosca® (5%); isca Samaritá Tradicional® (5%); levedura Torula®; Bio Anastrepha® (5%); Ceratrap® e suco de goiaba (50%), com 3 avaliações semanais. Os dados da captura foram submetidos à análise de variância e às médias comparadas (Tukey 5%). Os valores de Mosca por Armadilha por Dia (MAD) foram calculados. A correlação entre moscas e as variáveis meteorológicas foi avaliada e o custo mensal das iscas foi calculado. Foram coletados 37.917 indivíduos do gênero Anastrepha e 122 moscas da espécie Ceratitis capitata, sendo a Anastrepha spp. o principal gênero de mosca-das-frutas da região. O produto Ceratrap mostrou-se superior, seguido pelas iscas Torula, Isca Mosca e Bio Anastrepha; a Isca Samaritá e o suco de goiaba apresentaram os menores resultados de captura. O padrão de captura de fêmeas foi semelhante ao total. Verificou-se uma queda na uniformidade de atração de todos os tratamentos, sendo o Ceratrap o que apresentou maior constância após sete dias. As correlações entre os fatores meteorológicos e a flutuação populacional foram positivas e significativas apenas para a precipitação. Os tratamentos mais onerosos (Ceratrap e Torula) também foram os mais eficientes e seletivos, sendo o produto Ceratrap o que demandou menor mão de obra.(AU)

How Survey Design Affects Monkey Counts: A Case Study on Individually Recognized Spider Monkeys (Ateles geoffroyi).

The fast movement and high degree of fission-fusion dynamics of spider monkeys (Ateles spp.) make them notoriously difficult to survey. We examined which aspects of survey design affect spider monkey sightings along transects in a group of individually recognized spider monkeys (Ateles geoffroyi) in Punta Laguna, Yucatan, Mexico. We calculated the number of monkeys and subgroups sighted per transect walk. Using generalized linear models, we found no effect of the number of observers, transect type (new vs. existing), walking speed, or time of day on individual monkey counts or subgroup counts. Recounting of individuals was relatively rare and occurred when transects were walked relatively slowly. We missed more young than adult monkeys. The group composition based on survey data was similar to the known group composition. Based on our findings we recommend that surveys performed on relatively flat terrain be conducted at speeds similar to or faster than the moving speed of spider monkeys to minimize recounting of individuals and that young:adult female ratios based on survey data be interpreted as conservative indicators of population health. The novel methods presented to determine sources of bias in population estimates are applicable to a wide range of primates that are difficult to survey.

Development of a Low-Cost and Effective Trapping Device for Apple Maggot Fly (Diptera: Tephritidae) Monitoring and Control in Mexican Commercial Hawthorn Groves.

Few efforts have been made in Mexico to monitor Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) in commercial hawthorn (Crataegus spp.) crops. Therefore, the main objectives of this study were to evaluate infestation levels of R. pomonella in feral and commercial Mexican hawthorn and to assess the efficacy of different trap-lure combinations to monitor the pest. Wild hawthorn was more infested than commercially grown hawthorn at the sample site. No differences among four commercial baits (Biolure, ammonium carbonate, CeraTrap, and Captor + borax) were detected when used in combination with a yellow sticky gel (SG) adherent trap under field conditions. However, liquid lures elicited a slightly higher, although not statistically different, capture. Cage experiments in the laboratory revealed that flies tended to land more often on the upper and middle than lower-bottom part of polyethylene (PET) bottle traps with color circles. Among red, orange, green, and yellow circles attached to a bottle trap, only yellow circles improved fly captures compared with a colorless trap. A PET bottle trap with a red circle over a yellow background captured more flies than a similar trap with yellow circles. An SG adherent yellow panel trap baited with ammonium carbonate was superior to the improved PET bottle trap (red over a yellow background) baited with different liquid proteins, but a higher proportion of females and no differences in fly detection were measured in PET traps baited with protein lures. These trials open the door for future research into development of a conventional nonadherent trap to monitor or control R. pomonella.

Differential patterns of Batrachochytrium dendrobatidis infection in relict amphibian populations following severe disease-associated declines.

Global amphibian biodiversity has declined dramatically in the past 4 decades, and many amphibian species have declined to near extinction as a result of emergence of the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd). However, persistent or recovering populations of several amphibian species have recently been rediscovered, and such populations may illustrate how amphibian species that are highly susceptible to chytridiomycosis may survive in the presence of Bd. We conducted field surveys for Bd infection in 7 species of Costa Rican amphibians (all species that have declined to near extinction but for which isolated populations persist) to characterize infection profiles in highly Bd-susceptible amphibians post-decline. We found highly variable patterns in infection, with some species showing low prevalence (~10%) and low infection intensity and others showing high infection prevalence (>80%) and either low or high infection intensity. Across sites, infection rates were negatively associated with mean annual precipitation, and infection intensity across sites was negatively associated with mean average temperatures. Our results illustrate that even the most Bd-susceptible amphibians can persist in Bd-enzootic ecosystems, and that multiple ecological or evolutionary mechanisms likely exist for host-pathogen co-existence between Bd and the most Bd-susceptible amphibian species. Continued monitoring of these populations is necessary to evaluate population trends (continuing decline, stability, or population growth). These results should inform efforts to mitigate impacts of Bd on amphibians in the field.

Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon

Previous studies have demonstrated that river-based surveys can provide an inexpensive source of information for neotropical zoologists, yet little information is available to inform the application of this technique for the long term monitoring of neotropical turtle species. We aimed to fill this gap by presenting an assessment of data collected during 333 river surveys over 50 months along rivers in a newly protected area in the Peruvian Amazon. A total of 14,138 basking Podocnemis unifilis Troschel, 1848 were recorded during 13,510 km of river-based surveys. We used generalized additive models (GAMs) to explore the influence of a series of abiotic and seasonal variables on the recorded abundances at two temporal scales: monthly and per trip. Our analysis revealed that there was a significant increase in turtle abundances during the study period and we also found a significant seasonal periodicity in monthly abundances. Abiotic factors strongly influenced trip level abundances, with more individuals per kilometer recorded during sunny days in the dry season, with temperatures between 25 and 30°C. The results demonstrate that turtle populations are increasing following the establishment of the protected area and that river-based surveys are likely to be more effective when carried out within a limited set of key abiotic conditions.

Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon

Previous studies have demonstrated that river-based surveys can provide an inexpensive source of information for neotropical zoologists, yet little information is available to inform the application of this technique for the long term monitoring of neotropical turtle species. We aimed to fill this gap by presenting an assessment of data collected during 333 river surveys over 50 months along rivers in a newly protected area in the Peruvian Amazon. A total of 14,138 basking Podocnemis unifilis Troschel, 1848 were recorded during 13,510 km of river-based surveys. We used generalized additive models (GAMs) to explore the influence of a series of abiotic and seasonal variables on the recorded abundances at two temporal scales: monthly and per trip. Our analysis revealed that there was a significant increase in turtle abundances during the study period and we also found a significant seasonal periodicity in monthly abundances. Abiotic factors strongly influenced trip level abundances, with more individuals per kilometer recorded during sunny days in the dry season, with temperatures between 25 and 30°C. The results demonstrate that turtle populations are increasing following the establishment of the protected area and that river-based surveys are likely to be more effective when carried out within a limited set of key abiotic conditions.

Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon

Previous studies have demonstrated that river-based surveys can provide an inexpensive source of information for neotropical zoologists, yet little information is available to inform the application of this technique for the long term monitoring of neotropical turtle species. We aimed to fill this gap by presenting an assessment of data collected during 333 river surveys over 50 months along rivers in a newly protected area in the Peruvian Amazon. A total of 14,138 basking Podocnemis unifilis Troschel, 1848 were recorded during 13,510 km of river-based surveys. We used generalized additive models (GAMs) to explore the influence of a series of abiotic and seasonal variables on the recorded abundances at two temporal scales: monthly and per trip. Our analysis revealed that there was a significant increase in turtle abundances during the study period and we also found a significant seasonal periodicity in monthly abundances. Abiotic factors strongly influenced trip level abundances, with more individuals per kilometer recorded during sunny days in the dry season, with temperatures between 25 and 30°C. The results demonstrate that turtle populations are increasing following the establishment of the protected area and that river-based surveys are likely to be more effective when carried out within a limited set of key abiotic conditions.

Mutagénesis ambiental y el uso de biomarcadores para predecir el riesgo de cáncer: [revisión] / Environmental mutagenesis and use of biomarkers in cancer risk prediction: [review]

The field of environmental mutagenesis or toxicology genetics aims to study the genetic damage that leads to mutations produced by physical, chemical and biological agents, to identify these agents and analyze their interactions and ways of action. There are enough experimental and epidemiological evidences implicating mutations in oncogenes, tumor suppressor genes and DNA repair genes as determinants in the onset and progression of the neoplastic process. A valuable tool in public and occupational health is the monitoring of populations exposed to potentially hazardous agents. The objective is to protect the health and quality of life of high risk groups on account of the nature of the agents of exposure. Monitoring of genotoxic effects in exposed populations as well as the analysis of susceptibility polymorphism are visualized as key tools in the realm of future public and occupational health in order to prevent the occurrence of environmental and specially occupational origin of tumors. This paper reviews the main concepts concerning this issue and refers to studies on the subject in Costa Rica.