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Regular evaluation of jaguar (Panthera onca) population status is an important part of conservation decision-making. Currently, camera trapping has become the standard method used to estimate jaguar abundance and demographic parameters, though evidence has shown the potential for sex ratio biases and density overestimates. In this study, we used camera trap data combined with satellite telemetry data from one female jaguar to estimate jaguar population density in the dry forest of Santa Rosa National Park in the Guanacaste Conservation Area of northwestern Costa Rica. We analyzed camera trap data collected from June 2016 to June 2017 using spatial capture-recapture methods to estimate jaguar density. In total, 19 individual jaguars were detected (11 males; 8 females) with a resulting estimated population density of 2.6 females (95% [CI] 1.7-4.0) and 5.0 male (95% [CI] 3.4-7.4) per 100 km2. Based on telemetry and camera trap data, camera placement might bias individual detections by sex and thus overall density estimates. We recommend population assessments be made at several consecutive 3-month intervals, that larger areas be covered so as not to restrict surveys to one or two individual home ranges, as in our case, and to carry out long-term camera monitoring programs instead of short-term studies to better understand the local population, using auxiliary telemetry data to adjust field designs and density estimations to improve support for jaguar conservation strategies.

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The selection of a survey method of free-roaming dog populations should be based on analyses of local capacities and management priorities. Here, we compare the results of surveys of the stray dog population in Quito, Ecuador, using two different methodologies and propose an alternative method for future surveys in the city. We carried out all surveys in ~5 km-transects in a sample of eight urban and eight rural parishes (16 transects total). In 2018, we used the capture-recapture method to estimate absolute population size and 95% CI. We began transect surveys at 04 h 00 (local time) and identified individuals with photographs. The main limitations of this method were errors in identifying individuals, since photographs were not always clear, partly due to low light conditions during the surveys. This method also required more time and more complex logistics. In 2019, we used distance sampling to estimate population density and began the surveys at 08 h 00 (local time). Errors in the estimation of animal-observer distances and angles were our main concern when using this method. For future surveys, we propose to carry out direct observations of dog abundance (number of free-roaming dogs/km) during street counts, complemented with capture-recapture surveys every 5 years. This alternative method albeit simple, is sensitive enough to (1) provide local authorities with objective assessments of management interventions, (2) better understanding the dynamics of free-roaming dog populations and (3) increasing public awareness about the problem of pet abandonment through citizen participation in the surveys.

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BACKGROUND: There is scarce epidemiological data on Multiple Sclerosis (MS) in Latin America. National epidemiological studies are needed to guide the health policy related to MS. OBJECTIVE: To determine MS national prevalence in Peru and describe clinical and epidemiological characteristics of the disease. METHODS: We conducted a cross-sectional prevalence study in Peru's four largest regions using two sources. We included adult patients diagnosed with MS by a neurologist using the McDonald criteria. We performed a capture-recapture analysis using the nearly unbiased estimator model, and calculated prevalence as the proportion of the adult Peruvian population in 2016. Additionally, we summarized patients epidemiological and clinical characteristics. RESULTS: We identified 417 cases: 135 from the first source and 282 from the one. We found a point prevalence of 9.12 cases per 100 000 inhabitants (95% CI: 5.6 - 12.6). The age range was 35 to 45 years-old, and 51.9% were female. The most common type of MS was relapsing-remitting (79.3%) and the most frequent treatment was subcutaneous IFN-1b (40.7%). CONCLUSION: Peru has a medium MS prevalence compared to other Latin American countries. Lima is the region with the highest number of cases, with similar clinical characteristics to other countries in the region.

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RESUMEN Introducción: la epilepsia constituye una de las enfermedades neurológicas crónicas más comunes en niños. Objetivo: determinar la prevalencia general y según edad, sexo y etiología de la epilepsia en el área de salud del policlínico Jimmy Hirzel del municipio Bayamo, provincia de Granma en los pacientes menores de 15 años. Métodos: se realizó una investigación descriptiva y transversal, utilizándose entre las técnicas estadísticas el método de captura-recaptura. Resultados: la tasa de prevalencia general encontrada fue de 4,54 (IC 95%, 4,33-4,74). Conclusiones: se concluyó que la prevalencia de la epilepsia en el área de salud estudiada presenta valores similares a los encontrados en países desarrollados.

ABSTRACT Introduction: epilepsy is one of the most common chronic neurological diseases in children. Objective: to determine the general prevalence and according to age, sex and etiology of epilepsy in the health area of the Jimmy Hirzel polyclinic of the Bayamo municipality, Granma province in patients under 15 years of age. Methods: a descriptive and cross-sectional investigation was carried out, using the capture-recapture method among the statistical techniques. Results: the general prevalence rate found was 4.54 (95% CI, 4.33-4.74). Conclusions: it was concluded that the prevalence of epilepsy in the health area studied presents values similar to those found in developed countries.

RESUMO Introdução: a epilepsia é uma das doenças neurológicas crônicas mais comuns em crianças. Objetivo: determinar a prevalência geral e de acordo com a idade, sexo e etiologia da epilepsia na área de saúde da policlínica Jimmy Hirzel do município de Bayamo, província de Granma em pacientes menores de 15 anos. Métodos: foi realizada uma investigação descritiva e transversal, utilizando o método de captura-recaptura dentre as técnicas estatísticas. Resultados: a taxa de prevalência geral encontrada foi de 4,54 (IC 95%, 4,33-4,74). Conclusões: concluiu-se que a prevalência de epilepsia na área da saúde estudada apresenta valores semelhantes aos encontrados em países desenvolvidos.

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Introduction: Group or colony size is an important variable that is related to biological, ecological, and conservation aspects of bats. However, estimating the size of each colony or group in roosts used by more than one species is particularly difficult, especially when recapture rates are very low (< 10 %). Objective: Estimate the colony size of 14 species of bats: one emballonurid, one natalid, four mormoopids, seven phyllostomids, and one vespertilionid, which roosted throughout one year (July 2016 to June 2017) in a mine and two caves -Cerro Huatulco and El Apanguito- in the Sierra Sur and Costa of the state of Oaxaca. Methods: We constructed capture-recapture histories per species and roost, and for species for which we obtained recaptures that represented at least 10 % of the captures, we used the probabilistic Cormack-Jolly-Seber model. In the case of species with no recaptures or with a recapture proportion lower than 10 %, we estimated the number of individuals per roost by applying the same proportion between the number of captured specimens and the estimated number for species with recaptures greater than 10 % and that they belonged to the same family or trophic guild. Results: The total estimated number of bats in the three studied roosts was 20 105. The highest colony size estimates were for the mormoopids Pteronotus fulvus and P. mesoamericanus from El Apanguito and P. fulvus from Cerro Huatulco, with 6 609, 4 092 and 2 212 individuals, respectively. Conclusions: The methodology used in this study allowed estimating the colony size for all registered species, even though only for 21.42 % the recapture rates were greater than 10 %. Therefore, we consider that this methodology represents a viable alternative to estimate colony size in other roosts. This information, together with the high species richness and importance for reproductive processes, allow us to propose these sites as Bat Protection and Conservation Areas in Mexico.

Introducción: El tamaño del grupo o colonia es una variable importante que está relacionada con los aspectos biológicos, ecológicos y de conservación de los murciélagos. Sin embargo, estimar el tamaño de cada colonia o grupo en refugios utilizados por más de una especie es particularmente difícil, especialmente cuando las tasas de recaptura son muy bajas (< 10 %). Objetivo: Estimar el tamaño de la colonia de 14 especies de murciélagos: un emballonúrido, un natálido, cuatro mormópidos, siete filostómidos y un vespertiliónido, que se refugiaron durante un año (Julio 2016 a Junio 2017) en una mina y dos cuevas -Cerro Huatulco y El Apanguito- en la Sierra Sur y Costa del estado de Oaxaca. Métodos: Construimos historias de captura-recaptura por especie y refugio, y para las especies que se obtuvieron recapturas que representaban al menos el 10 % de las capturas, utilizamos un modelo probabilístico de Cormack-Jolly-Seber para estimar el tamaño de sus colonias. En el caso de especies sin recapturas o con una proporción de recaptura inferior al 10 %, estimamos el número de individuos por refugio aplicando la misma proporción entre el número de individuos capturados y el número total estimado para las especies con recapturas mayores del 10 % y que pertenecieran a la misma familia o gremio trófico registradas con la mayor similitud ecológica y con suficientes recapturas para aplicar el modelo Cormack-Jolly-Seber. Resultados: El número total estimado de murciélagos en los tres refugios de estudio fue de 20 105. Las estimaciones de tamaño de colonia más altos fueron para los mormópidos Pteronotus fulvus y P. mesoamericanus de El Apanguito y P. fulvus en Cerro Huatulco, con 6 609, 4 092 and 2 212 individuos, respectivamente. Conclusiones: La metodología utilizada en este estudio permitió estimar el tamaño de la colonia para todas las especies registradas, a pesar de que solo para el 21.42 % las tasas de recaptura fueron superiores al 10 %. Por lo tanto, consideramos que esta metodología representa una alternativa viable para estimar el tamaño de colonia en otros refugios. Esta información, junto con los procesos de alta riqueza de especies y reproducción que tienen lugar en esta área, permiten proponer estos sitios como áreas de protección y conservación de murciélagos en México.

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BACKGROUND: In Brazil, both the Civil Registry (CR) and Ministry of Health (MoH) Mortality Information System (SIM) are sources of routine mortality data, but neither is 100% complete. Deaths from these two sources can be linked to facilitate estimation of completeness of mortality reporting and measurement of adjusted mortality indicators using generalized linear modeling (GLM). METHODS: The 2015 and 2016 CR and SIM data were linked using deterministic methods. GLM with covariates of the deceased's sex, age, state of residence, cause of death and place of death, and municipality-level education decile and population density decile, was used to estimate total deaths and completeness nationally, subnationally and by population sub-group, and to identify the characteristics of unreported deaths. The empirical completeness method and Global Burden of Disease (GBD) 2017 estimates were comparators at the national and state level. RESULTS: Completeness was 98% for SIM and 95% for CR. The vast majority of deaths in Brazil were captured by either system and 94% were reported by both sources. For each source, completeness was lowest in the north. SIM completeness was consistently high across all sub-groups while CR completeness was lowest for deaths at younger ages, outside facilities, and in the lowest deciles of municipality education and population density. There was no clear municipality-level relationship in SIM and CR completeness, suggesting minimal dependence between sources. The empirical completeness method model 1 and GBD completeness estimates were each, on average, less than three percentage points different from GLM estimates at the state level. Life expectancy was lowest in the northeast and 7.5 years higher in females than males. CONCLUSIONS: GLM using socio-economic and demographic covariates is a valuable tool to accurately estimate completeness from linked data sources. Close scrutiny of the quality of variables used to link deaths, targeted identification of unreported deaths in poorer, northern states, and closer coordination of the two systems will help Brazil achieve 100% death reporting completeness. The results also confirm the validity of the empirical completeness method.

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HIV disproportionately affects men who have sex with men and transwomen in Latin America. Globally, efforts to map, enumerate, and describe male and transwomen sex workers (MTSWs) are limited. We mapped and described venue- and non-venue-based MTSWs and enumerated venuebased MTSWs in Lima, Peru's capital. With venue-based MTSWs, we identified and described the venues, SWs, and clients and enumerated the SWs. With non-venue-based MTSWs, we described SW offerings and SWs. Male SWs (MSWs) are concentrated downtown, with many moving online. Transwomen SWs (TSWs) are spread across metropolitan Lima, with fewer online. At venues, there are more TSWs than MSWs, TSWs reported more HIV and sexual risk behaviors, and MSWs had more female partners. Non-venue-based MSWs used condoms less than venue-based MSWs. Results support systematic efforts to describe hard-to-reach MTSWs and their different types of partners, all of whom have unique, differing needs for HIV/ STI education, prevention, testing, and care services.

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BACKGROUND: Enumerating dog populations is essential to plan and evaluate rabies vaccination campaigns. To estimate vaccination coverage and dog population size in a Haitian commune, 15 sight-resight counts were conducted over two days following a government-sponsored vaccination campaign. METHODS: Dogs received temporary laminated collars and livestock wax marks on the head and sides at the time of rabies vaccination. After the vaccination campaign, pairs of surveyors walked pre-defined routes through targeted neighborhoods, photographing and recording characteristics and location of each dog seen on a standardized data sheet. On the second survey day, surveyors retraced the prior day's track, followed the same procedure, and indicated in addition whether they believed the dogs were resighted from the prior day. After completion of the field survey, two independent evaluators reviewed photographs and characteristics of each dog to assess which had vaccination marks and which were resighted. Surveyor and photo-reviewer sight-resight decisions were compared using Cohen's kappa, and population estimates were compared using Lincoln-Petersen 95% confidence intervals. RESULTS: Field-surveyors identified dogs consistent with the photograph evaluations in 629 out of 800 instances (78.6%, Cohen's kappa of 0.12). Despite this inconsistency, the population estimates resulting from the field and final determinations were not significantly different at 1,789 (95% CI 1,677 to 1,901) and 1,978 (95% CI 1,839 to 2,118). Vaccination coverage was also the same at 55% and 56%; however, an observed vaccination mark loss of 13.8% suggests that the true coverage may have been closer to 64%. CONCLUSION: Using photos improved dog identification during the sight-resight study, leading to a higher population estimate. Despite using a 2-mark system to temporarily identify vaccinated dogs, a significant proportion had lost all identifying marks by the second day of field surveys. Efforts to estimate vaccination coverage using sight-resight surveys should consider improvement of marking techniques or better accounting for potential loss of marks in their free-roaming dog vaccination coverage assessments.

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Open population capture-recapture models are widely used to estimate population demographics and abundance over time. Bayesian methods exist to incorporate open population modeling with spatial capture-recapture (SCR), allowing for estimation of the effective area sampled and population density. Here, open population SCR is formulated as a hidden Markov model (HMM), allowing inference by maximum likelihood for both Cormack-Jolly-Seber and Jolly-Seber models, with and without activity center movement. The method is applied to a 12-year survey of male jaguars (Panthera onca) in the Cockscomb Basin Wildlife Sanctuary, Belize, to estimate survival probability and population abundance over time. For this application, inference is shown to be biased when assuming activity centers are fixed over time, while including a model for activity center movement provides negligible bias and nominal confidence interval coverage, as demonstrated by a simulation study. The HMM approach is compared with Bayesian data augmentation and closed population models for this application. The method is substantially more computationally efficient than the Bayesian approach and provides a lower root-mean-square error in predicting population density compared to closed population models.

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Juvenile growth rates are thought to be restricted by available food resources. In animals that grow throughout the year, such as tropical lizards, growth is therefore predicted to be faster during the rainy season. We test this prediction using a population of Anolis nebulosusby describing the growth trajectories of both sexes using nonlinear regression models, and we then correlate the growth rates of individuals with food available in the environment, precipitation, and temperature. The Von Bertalanffy model fits the growth rates of the females better, while the logistic-by-length model fits the males better. According to both models, the males grew faster than females, reaching slightly smaller sizes at adulthood. Males reached sexual maturity when 35 mm long, at an age of seven months, and females matured at 37 mm (SVL), taking nine months to reach this size. In 1989, juvenile males and females grew more in both seasons (rainy and dry) than adults; for 1990, there were no differences by season or between age classes. These results are interesting since in the 1989 and 1990 rainy seasons, practically the same orders of prey and the greatest abundance of prey available in the environment were registered. A possible explanation could be that predation was more intense in 1990 than in 1989. There is little evidence that food, temperature, and humidity affect growth rates of A. nebulosus, refuting our predictions. This is mainly due to the low variation in growth observed in 1990. Therefore we think that the growth of this species reflects a complex combination of ecological and genetic factors.

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The practice of capture-recapture to estimate the diversity is well known to many animal groups, however this practice in the larval phase of anuran amphibians is incipient. We aimed at evaluating the Lincoln estimator, Venn diagram and Bayes theorem in the inference of population size of a larval phase anurocenose from lotic environment. The adherence of results was evaluated using the Kolmogorov-Smirnov test. The marking of tadpoles for later recapture and methods measurement was made with eosin methylene blue. When comparing the results of Lincoln-Petersen estimator corresponding to the Venn diagram and Bayes theorem, we detected percentage differences per sampling, i.e., the proportion of sampled anuran genera is kept among the three methods, although the values are numerically different. By submitting these results to the Kolmogorov-Smirnov test we have found no significant differences. Therefore, no matter the estimator, the measured value is adherent and estimates the total population. Together with the marking methodology, which did not change the behavior of tadpoles, the present study helps to fill the need of more studies on larval phase of amphibians in Brazil, especially in semi-arid northeast.(AU)

A prática de captura-recaptura para a estimação da diversidade é bem conhecida para diversos grupos animais, porém na fase larvar de anfíbios anuros essa prática é incipiente. Objetivamos avaliar os métodos do estimador de Lincoln, diagrama de Venn e o teorema de Bayes na inferência do tamanho populacional de uma anurocenose em fase larvar de ambiente lótico. A aderência dos resultados foi avaliada através do teste de Kolmogorov-Smirnov. A marcação dos girinos para posterior recaptura e aferição dos métodos foi feita com eosina de azul de metileno. Ao compararmos os resultados do estimador de Lincoln que corresponde com o do diagrama de Venn e com o teorema de Bayes detectamos diferenças percentuais por amostragem, isto é, a manutenção da proporção dos gêneros de anuros amostrados é mantida entre os três métodos, embora com valores numericamente diferentes. Ao submetermos esses resultados ao teste Kolmogorov-Smirnov não encontramos diferenças significativas. Logo, qualquer que seja o estimador o valor aferido é aderente e estima a população total. Aliado à metodologia de marcação que não alterou o comportamento dos girinos, o presente estudo ajuda a preencher a necessidade de mais estudos na fase larvar dos anfíbios no Brasil, em especial no semiárido nordestino.(AU)

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BACKGROUND: Site fidelity is considered as an animal's tendency to return to a previously occupied place; this is a component of animal behaviour that allows us to understand movement patterns and aspects related to the animal's life history. Although there are many site fidelity metrics, the lack of standardisation presents a considerable challenge in terms of comparability among studies. METHODS: This investigation focused on the theoretical development of a standardised composite site fidelity index and its statistical distribution in order to obtain reliable population-level site fidelity comparisons. The arithmetic and harmonic means were used as mathematical structures in order to create different indexes by combining the most commonly used indicators for site fidelity such as Occurrence, Permanence and Periodicity. The index performance was then evaluated in simulated populations and one real population of Commerson's dolphins (Cephalorhynchus commersonii (Lacépède 1804)). In the first case, the indexes were evaluated based on how they were affected by different probability values such as the occurrence of the individual within the study area (φ) and capture probability (p). As a precision measure for the comparison of the indexes, the Wald confidence interval (CI) and the mean square error were applied. Given that there was no previous data concerning the distribution parameters of this population, bootstrap CIs were applied for the study case. RESULTS: Eight alternative indexes were developed. The indexes with an arithmetic mean structure, in general, had a consistently inferior performance than those with a harmonic mean structure. The index IH4, in particular, achieved the best results in all of the scenarios and in the study case. Additionally, this index presented a normal distribution. As such, it was proposed as a standardised measure for site fidelity (Standardised Site Fidelity Index-SSFI). DISCUSSION: The SSFI is the first standardised metric that quantifies site fidelity at a populational level. It is an estimator that varies between zero and one and works in situations where detection is not perfect and effort can be constant or not. Moreover, it has an associated CI that allows users to make comparisons.

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Abstract The practice of capture-recapture to estimate the diversity is well known to many animal groups, however this practice in the larval phase of anuran amphibians is incipient. We aimed at evaluating the Lincoln estimator, Venn diagram and Bayes theorem in the inference of population size of a larval phase anurocenose from lotic environment. The adherence of results was evaluated using the Kolmogorov-Smirnov test. The marking of tadpoles for later recapture and methods measurement was made with eosin methylene blue. When comparing the results of Lincoln-Petersen estimator corresponding to the Venn diagram and Bayes theorem, we detected percentage differences per sampling, i.e., the proportion of sampled anuran genera is kept among the three methods, although the values are numerically different. By submitting these results to the Kolmogorov-Smirnov test we have found no significant differences. Therefore, no matter the estimator, the measured value is adherent and estimates the total population. Together with the marking methodology, which did not change the behavior of tadpoles, the present study helps to fill the need of more studies on larval phase of amphibians in Brazil, especially in semi-arid northeast.

Resumo A prática de captura-recaptura para a estimação da diversidade é bem conhecida para diversos grupos animais, porém na fase larvar de anfíbios anuros essa prática é incipiente. Objetivamos avaliar os métodos do estimador de Lincoln, diagrama de Venn e o teorema de Bayes na inferência do tamanho populacional de uma anurocenose em fase larvar de ambiente lótico. A aderência dos resultados foi avaliada através do teste de Kolmogorov-Smirnov. A marcação dos girinos para posterior recaptura e aferição dos métodos foi feita com eosina de azul de metileno. Ao compararmos os resultados do estimador de Lincoln que corresponde com o do diagrama de Venn e com o teorema de Bayes detectamos diferenças percentuais por amostragem, isto é, a manutenção da proporção dos gêneros de anuros amostrados é mantida entre os três métodos, embora com valores numericamente diferentes. Ao submetermos esses resultados ao teste Kolmogorov-Smirnov não encontramos diferenças significativas. Logo, qualquer que seja o estimador o valor aferido é aderente e estima a população total. Aliado à metodologia de marcação que não alterou o comportamento dos girinos, o presente estudo ajuda a preencher a necessidade de mais estudos na fase larvar dos anfíbios no Brasil, em especial no semiárido nordestino.

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The decline of wildlife populations due to emerging infectious disease often shows a common pattern: the parasite invades a naive host population, producing epidemic disease and a population decline, sometimes with extirpation. Some susceptible host populations can survive the epidemic phase and persist with endemic parasitic infection. Understanding host-parasite dynamics leading to persistence of the system is imperative to adequately inform conservation practice. Here we combine field data, statistical and mathematical modelling to explore the dynamics of the apparently stable Rhinoderma darwinii-Batrachochytrium dendrobatidis (Bd) system. Our results indicate that Bd-induced population extirpation may occur even in the absence of epidemics and where parasite prevalence is relatively low. These empirical findings are consistent with previous theoretical predictions showing that highly pathogenic parasites are able to regulate host populations even at extremely low prevalence, highlighting that disease threats should be investigated as a cause of population declines even in the absence of an overt increase in mortality.

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We developed a statistical framework to quantify mortality rates in canopy trees observed using time series from high-resolution remote sensing. By timing the acquisition of remote sensing data with synchronous annual flowering in the canopy tree species Handroanthus guayacan, we made 2,596 unique detections of 1,006 individual adult trees within 18,883 observation attempts on Barro Colorado Island, Panama (BCI) during an 11-yr period. There were 1,057 observation attempts that resulted in missing data due to cloud cover or incomplete spatial coverage. Using the fraction of 123 individuals from an independent field sample that were detected by satellite data (109 individuals, 88.6%), we estimate that the adult population for this species on BCI was 1,135 individuals. We used a Bayesian state-space model that explicitly accounted for the probability of tree detection and missing observations to compute an annual adult mortality rate of 0.2%·yr-1 (SE = 0.1, 95% CI = 0.06-0.45). An independent estimate of the adult mortality rate from 260 field-checked trees closely matched the landscape-scale estimate (0.33%·yr-1 , SE = 0.16, 95% CI = 0.12-0.74). Our proof-of-concept study shows that one can remotely estimate adult mortality rates for canopy tree species precisely in the presence of variable detection and missing observations.

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Abstract The practice of capture-recapture to estimate the diversity is well known to many animal groups, however this practice in the larval phase of anuran amphibians is incipient. We aimed at evaluating the Lincoln estimator, Venn diagram and Bayes theorem in the inference of population size of a larval phase anurocenose from lotic environment. The adherence of results was evaluated using the Kolmogorov-Smirnov test. The marking of tadpoles for later recapture and methods measurement was made with eosin methylene blue. When comparing the results of Lincoln-Petersen estimator corresponding to the Venn diagram and Bayes theorem, we detected percentage differences per sampling, i.e., the proportion of sampled anuran genera is kept among the three methods, although the values are numerically different. By submitting these results to the Kolmogorov-Smirnov test we have found no significant differences. Therefore, no matter the estimator, the measured value is adherent and estimates the total population. Together with the marking methodology, which did not change the behavior of tadpoles, the present study helps to fill the need of more studies on larval phase of amphibians in Brazil, especially in semi-arid northeast.

Resumo A prática de captura-recaptura para a estimação da diversidade é bem conhecida para diversos grupos animais, porém na fase larvar de anfíbios anuros essa prática é incipiente. Objetivamos avaliar os métodos do estimador de Lincoln, diagrama de Venn e o teorema de Bayes na inferência do tamanho populacional de uma anurocenose em fase larvar de ambiente lótico. A aderência dos resultados foi avaliada através do teste de Kolmogorov-Smirnov. A marcação dos girinos para posterior recaptura e aferição dos métodos foi feita com eosina de azul de metileno. Ao compararmos os resultados do estimador de Lincoln que corresponde com o do diagrama de Venn e com o teorema de Bayes detectamos diferenças percentuais por amostragem, isto é, a manutenção da proporção dos gêneros de anuros amostrados é mantida entre os três métodos, embora com valores numericamente diferentes. Ao submetermos esses resultados ao teste Kolmogorov-Smirnov não encontramos diferenças significativas. Logo, qualquer que seja o estimador o valor aferido é aderente e estima a população total. Aliado à metodologia de marcação que não alterou o comportamento dos girinos, o presente estudo ajuda a preencher a necessidade de mais estudos na fase larvar dos anfíbios no Brasil, em especial no semiárido nordestino.

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Abstract The practice of capture-recapture to estimate the diversity is well known to many animal groups, however this practice in the larval phase of anuran amphibians is incipient. We aimed at evaluating the Lincoln estimator, Venn diagram and Bayes theorem in the inference of population size of a larval phase anurocenose from lotic environment. The adherence of results was evaluated using the Kolmogorov-Smirnov test. The marking of tadpoles for later recapture and methods measurement was made with eosin methylene blue. When comparing the results of Lincoln-Petersen estimator corresponding to the Venn diagram and Bayes theorem, we detected percentage differences per sampling, i.e., the proportion of sampled anuran genera is kept among the three methods, although the values are numerically different. By submitting these results to the Kolmogorov-Smirnov test we have found no significant differences. Therefore, no matter the estimator, the measured value is adherent and estimates the total population. Together with the marking methodology, which did not change the behavior of tadpoles, the present study helps to fill the need of more studies on larval phase of amphibians in Brazil, especially in semi-arid northeast.

Resumo A prática de captura-recaptura para a estimação da diversidade é bem conhecida para diversos grupos animais, porém na fase larvar de anfíbios anuros essa prática é incipiente. Objetivamos avaliar os métodos do estimador de Lincoln, diagrama de Venn e o teorema de Bayes na inferência do tamanho populacional de uma anurocenose em fase larvar de ambiente lótico. A aderência dos resultados foi avaliada através do teste de Kolmogorov-Smirnov. A marcação dos girinos para posterior recaptura e aferição dos métodos foi feita com eosina de azul de metileno. Ao compararmos os resultados do estimador de Lincoln que corresponde com o do diagrama de Venn e com o teorema de Bayes detectamos diferenças percentuais por amostragem, isto é, a manutenção da proporção dos gêneros de anuros amostrados é mantida entre os três métodos, embora com valores numericamente diferentes. Ao submetermos esses resultados ao teste Kolmogorov-Smirnov não encontramos diferenças significativas. Logo, qualquer que seja o estimador o valor aferido é aderente e estima a população total. Aliado à metodologia de marcação que não alterou o comportamento dos girinos, o presente estudo ajuda a preencher a necessidade de mais estudos na fase larvar dos anfíbios no Brasil, em especial no semiárido nordestino.

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Demographic information is the basis for evaluating and planning conservation strategies for an endangered species. However, in numerous situations there are methodological or financial limitations to obtain such information for some species. The marsh deer, an endangered Neotropical cervid, is a challenging species to obtain biological information. To help achieve such aims, the study evaluated the applicability of camera traps to obtain demographic information on the marsh deer compared to the traditional aerial census method. Fourteen camera traps were installed for three months on the Capão da Cruz floodplain, in state of São Paulo, and ten helicopter flyovers were made along a 13-kilometer trajectory to detect resident marsh deer. In addition to counting deer, the study aimed to identify the sex, age group and individual identification of the antlered males recorded. Population estimates were performed using the capture-mark-recapture method with the camera trap data and by the distance sampling method for aerial observation data. The costs and field efforts expended for both methodologies were calculated and compared. Twenty independent photographic records and 42 sightings were obtained and generated estimates of 0.98 and 1.06 ind/km², respectively. In contrast to the aerial census, camera traps allowed us to individually identify branch-antlered males, determine the sex ratio and detect fawns in the population. The cost of camera traps was 78% lower but required 20 times more field effort. Our analysis indicates that camera traps present a superior cost-benefit ratio compared to aerial surveys, since they are more informative, cheaper and offer simpler logistics. Their application extends the possibilities of studying a greater number of populations in a long-term monitoring.

Informações demográficas constituem a base para a avaliação e planejamento de estratégias de conservação de uma espécie ameaçada. No entanto, em muitas situações existem limitações metodológicas ou financeiras para a obtenção de tais informações para algumas espécies. O cervo-do-pantanal, um cervídeo neotropical ameaçado de extinção, é uma espécie desafiadora para obtenção de informações biológicas. Para suprir essa demanda, o presente trabalho avaliou a aplicabilidade das armadilhas fotográficas para obtenção de informações demográficas de cervo-do-pantanal em comparação com o tradicional método de censo aéreo. Na várzea Capão da Cruz, Estado de São Paulo, foram instaladas 14 armadilhas fotográficas durante três meses e realizados dez sobrevoos de helicóptero num trajeto de 13 km para detecção dos cervos-do-pantanal ali residentes. Além da contagem dos animais, objetivou-se identificar o sexo, a faixa etária e a identificação individual dos machos galhados registrados. As estimativas populacionais foram realizadas pelo método de captura-marcação-recaptura com os dados de armadilhas fotográficas e pelo método de amostragem por distâncias para os dados de observação aérea. Foram contabilizados e ponderados os custos e esforços de campo despendidos para ambas metodologias. Obteve-se 20 registros fotográficos independentes e 42 visualizações que geraram estimativas de 0,98 e 1,06 ind./km² respectivamente. Ao contrário do censo aéreo, as armadilhas fotográficas permitiram a identificação individual dos machos galhados, a proporção sexual e a detecção de filhotes na população. O custo das armadilhas fotográficas foi 78% menor, porém demandou um esforço de campo 20 vezes maior. Avaliamos que as armadilhas fotográficas apresentaram uma relação custo-benefício superiores em relação aos levantamentos aéreos, por ser mais informativa e barata e com uma logística mais simples. Sua aplicação abre a [...]

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RESUMO

ABSTRACT Demographic information is the basis for evaluating and planning conservation strategies for an endangered species. However, in numerous situations there are methodological or financial limitations to obtain such information for some species. The marsh deer, an endangered Neotropical cervid, is a challenging species to obtain biological information. To help achieve such aims, the study evaluated the applicability of camera traps to obtain demographic information on the marsh deer compared to the traditional aerial census method. Fourteen camera traps were installed for three months on the Capão da Cruz floodplain, in state of São Paulo, and ten helicopter flyovers were made along a 13-kilometer trajectory to detect resident marsh deer. In addition to counting deer, the study aimed to identify the sex, age group and individual identification of the antlered males recorded. Population estimates were performed using the capture-mark-recapture method with the camera trap data and by the distance sampling method for aerial observation data. The costs and field efforts expended for both methodologies were calculated and compared. Twenty independent photographic records and 42 sightings were obtained and generated estimates of 0.98 and 1.06 ind/km², respectively. In contrast to the aerial census, camera traps allowed us to individually identify branch-antlered males, determine the sex ratio and detect fawns in the population. The cost of camera traps was 78% lower but required 20 times more field effort. Our analysis indicates that camera traps present a superior cost-benefit ratio compared to aerial surveys, since they are more informative, cheaper and offer simpler logistics. Their application extends the possibilities of studying a greater number of populations in a long-term monitoring.

RESUMO Informações demográficas constituem a base para a avaliação e planejamento de estratégias de conservação de uma espécie ameaçada. No entanto, em muitas situações existem limitações metodológicas ou financeiras para a obtenção de tais informações para algumas espécies. O cervo-do-pantanal, um cervídeo neotropical ameaçado de extinção, é uma espécie desafiadora para obtenção de informações biológicas. Para suprir essa demanda, o presente trabalho avaliou a aplicabilidade das armadilhas fotográficas para obtenção de informações demográficas de cervo-do-pantanal em comparação com o tradicional método de censo aéreo. Na várzea Capão da Cruz, Estado de São Paulo, foram instaladas 14 armadilhas fotográficas durante três meses e realizados dez sobrevoos de helicóptero num trajeto de 13 km para detecção dos cervos-do-pantanal ali residentes. Além da contagem dos animais, objetivou-se identificar o sexo, a faixa etária e a identificação individual dos machos galhados registrados. As estimativas populacionais foram realizadas pelo método de captura-marcação-recaptura com os dados de armadilhas fotográficas e pelo método de amostragem por distâncias para os dados de observação aérea. Foram contabilizados e ponderados os custos e esforços de campo despendidos para ambas metodologias. Obteve-se 20 registros fotográficos independentes e 42 visualizações que geraram estimativas de 0,98 e 1,06 ind./km² respectivamente. Ao contrário do censo aéreo, as armadilhas fotográficas permitiram a identificação individual dos machos galhados, a proporção sexual e a detecção de filhotes na população. O custo das armadilhas fotográficas foi 78% menor, porém demandou um esforço de campo 20 vezes maior. Avaliamos que as armadilhas fotográficas apresentaram uma relação custo-benefício superiores em relação aos levantamentos aéreos, por ser mais informativa e barata e com uma logística mais simples. Sua aplicação abre a possibilidade para o estudo de um número maior de populações e o monitoramento contínuo e de longo prazo.

RESUMO

Demographic information is the basis for evaluating and planning conservation strategies for an endangered species. However, in numerous situations there are methodological or financial limitations to obtain such information for some species. The marsh deer, an endangered Neotropical cervid, is a challenging species to obtain biological information. To help achieve such aims, the study evaluated the applicability of camera traps to obtain demographic information on the marsh deer compared to the traditional aerial census method. Fourteen camera traps were installed for three months on the Capão da Cruz floodplain, in state of São Paulo, and ten helicopter flyovers were made along a 13-kilometer trajectory to detect resident marsh deer. In addition to counting deer, the study aimed to identify the sex, age group and individual identification of the antlered males recorded. Population estimates were performed using the capture-mark-recapture method with the camera trap data and by the distance sampling method for aerial observation data. The costs and field efforts expended for both methodologies were calculated and compared. Twenty independent photographic records and 42 sightings were obtained and generated estimates of 0.98 and 1.06 ind/km², respectively. In contrast to the aerial census, camera traps allowed us to individually identify branch-antlered males, determine the sex ratio and detect fawns in the population. The cost of camera traps was 78% lower but required 20 times more field effort. Our analysis indicates that camera traps present a superior cost-benefit ratio compared to aerial surveys, since they are more informative, cheaper and offer simpler logistics. Their application extends the possibilities of studying a greater number of populations in a long-term monitoring.(AU)

Informações demográficas constituem a base para a avaliação e planejamento de estratégias de conservação de uma espécie ameaçada. No entanto, em muitas situações existem limitações metodológicas ou financeiras para a obtenção de tais informações para algumas espécies. O cervo-do-pantanal, um cervídeo neotropical ameaçado de extinção, é uma espécie desafiadora para obtenção de informações biológicas. Para suprir essa demanda, o presente trabalho avaliou a aplicabilidade das armadilhas fotográficas para obtenção de informações demográficas de cervo-do-pantanal em comparação com o tradicional método de censo aéreo. Na várzea Capão da Cruz, Estado de São Paulo, foram instaladas 14 armadilhas fotográficas durante três meses e realizados dez sobrevoos de helicóptero num trajeto de 13 km para detecção dos cervos-do-pantanal ali residentes. Além da contagem dos animais, objetivou-se identificar o sexo, a faixa etária e a identificação individual dos machos galhados registrados. As estimativas populacionais foram realizadas pelo método de captura-marcação-recaptura com os dados de armadilhas fotográficas e pelo método de amostragem por distâncias para os dados de observação aérea. Foram contabilizados e ponderados os custos e esforços de campo despendidos para ambas metodologias. Obteve-se 20 registros fotográficos independentes e 42 visualizações que geraram estimativas de 0,98 e 1,06 ind./km² respectivamente. Ao contrário do censo aéreo, as armadilhas fotográficas permitiram a identificação individual dos machos galhados, a proporção sexual e a detecção de filhotes na população. O custo das armadilhas fotográficas foi 78% menor, porém demandou um esforço de campo 20 vezes maior. Avaliamos que as armadilhas fotográficas apresentaram uma relação custo-benefício superiores em relação aos levantamentos aéreos, por ser mais informativa e barata e com uma logística mais simples. Sua aplicação abre a [...](AU)

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