RESUMO
As sperm whales are important predators that control energy flux in the oceans, changes in their population can be used as a sentinel to measure of ecosystem health. The present study conducted a sperm whale survey of the eastern Midriff Islands Region in the Gulf of California over the course of nine years, recording sightings and collecting photographs of the fluke of sperm whale individuals. A photo-identification catalog was compiled, while individual recapture data were used to estimate the population size in the central portion of the Gulf of California, using a Jolly-Seber POPAN open population model. The results obtained show a yearly population of between 20 and 167 sperm whales, with a super population of 354 sperm whales observed between 2009 and 2015. However, from 2016 to 2018, no sightings of the species were recorded, which coincides with the decline observed in landings of their main prey, the jumbo squid, in the region. General additive model conducted on sperm whale sightings per unit of effort vs jumbo squid landings obtained an adjusted R2 of 0.644 and a deviance explained of 60.3%, indicating a good non-linear relationship between sightings of this odontocete and its prey availability. This evidence suggests that sperm whales departed the region between 2016 and 2018, due to a documented fishery collapse alongside changes of their main prey into its small phenotype, possibly as the result of increase warming conditions in surface and subsurface waters in the Gulf of California in the last three decades.
Assuntos
Decapodiformes , Cachalote , Animais , Cachalote/fisiologia , Decapodiformes/fisiologia , Dinâmica Populacional , Densidade Demográfica , Ecossistema , CaliforniaRESUMO
Thyrinteina arnobia (Lepidoptera: Geometridae) is a native American species. Despite its historical importance as an insect pest in Eucalyptus plantations, more information is needed regarding the population diversity, demography, and climatic variables associated with its distribution in different regions of Brazil. We used a phylogeographic approach to infer the genetic diversity, genetic structure, and demographic parameters of T. arnobia. We also conducted an ecological niche modeling (ENM) to predict suitable areas for T. arnobia occurrence in Brazil and other countries worldwide. Although T. arnobia populations have low genetic diversity in Brazil, we identified mitochondrial haplogroups predominating in different Brazilian regions and high ФST and ФCT values in AMOVA, suggesting a low frequency of insect movement among these regions. These results indicate that outbreaks of T. arnobia in Eucalyptus areas in different regions of Brazil are associated with local or regional populations, with no significant contribution from long-distance dispersal from different regions or biomes, suggesting that pest management strategies would be implemented on a regional scale. In Brazil, the demographic and spatial expansion signals of T. arnobia seem to be associated with the history of geographical expansion of Eucalyptus plantations, a new sustainable host for this species. ENM indicated that isothermality and annual rainfall are critical climatic factors for the occurrence of T. arnobia in tropical and subtropical areas in the Americas. ENM also suggested that T. arnobia is a potential pest in Eucalyptus areas in all Brazilian territory and in regions from Africa, Asia, and Oceania.
Assuntos
Ecossistema , Eucalyptus , Variação Genética , Filogeografia , Animais , Eucalyptus/parasitologia , Brasil , Lepidópteros/genética , Lepidópteros/fisiologia , Mariposas/fisiologia , Mariposas/genética , FilogeniaRESUMO
Rocky shore communities are shaped by complex interactions among environmental drivers and a range of biological processes. Here, we investigated the importance of abiotic and biotic drivers on the population structure of key rocky intertidal species at 62 sites, spanning â¼50% of the Brazilian rocky shoreline (i.e., â¼500 km). Large-scale population patterns were generally explained by differences in ocean temperature and wave exposure. For the gastropod species Lottia subrugosa, differences at smaller scales (i.e., 0.1-1 km) were better explained by other abiotic influences such as freshwater discharge and substrate roughness. Based on the general population patterns of intertidal species identified, three main oceanographic groups were observed: a cold-oligotrophic grouping at northern sites (Lakes sub-region), a eutrophic group associated with large estuaries and urban zones (Santos and Guanabara bays); and a transitional warm-water group found between the two more productive areas. Larger individuals of Stramonita brasiliensis, L. subrugosa and Echinolittorina lineolata were generally found in the cold-oligotrophic system (i.e., upwelling region), while small suspension feeders dominate the warm-eutrophic systems. Evidence of bottom-up regulation was not observed, and top-down regulation effects were only observed between the whelk S. brasiliensis and its mussel prey Pernaperna. Environmental drivers as compared to biotic interactions, therefore, play a key role determining the population structure of multiple intertidal species, across a range of spatial scales along the SW Atlantic shores.
Assuntos
Ecossistema , Brasil , Animais , Monitoramento Ambiental , Gastrópodes/fisiologia , Dinâmica Populacional , Biodiversidade , TemperaturaRESUMO
Studies on community composition and population structure of entomopathogenic fungi are imperative to link ecosystem functions to conservation biological control. We studied the diversity and abundance of Metarhizium spp. from soil of conventionally and organically farmed strawberry crops and from the adjacent field margins in two different climatic zones: Brazil (tropical) and Denmark (temperate), using the same isolating methods. In Brazilian strawberry soil, Metarhizium robertsii (n = 129 isolates) was the most abundant species, followed by M. humberi (n = 16); M. anisopliae (n = 6); one new taxonomically unassigned lineage Metarhizium sp. indet. 5 (n = 4); M. pingshaense (n = 1) and M. brunneum (n = 1). In Denmark, species composition was very different, with M. brunneum (n = 33) being isolated most commonly, followed by M. flavoviride (n = 6) and M. pemphigi (n = 5), described for the first time in Denmark. In total, 17 haplotypes were determined based on MzFG543igs sequences, four representing Danish isolates and 13 representing Brazilian isolates. No overall difference between the two climatic regimes was detected regarding the abundance of Metarhizium spp. in the soil in strawberry fields and the field margins. However, we found a higher Shannon's diversity index in organically managed soils, confirming a more diverse Metarhizium community than in soils of conventionally managed agroecosystems in both countries. These findings contribute to the knowledge of the indigenous diversity of Metarhizium in agricultural field margins with the potential to contribute to pest regulation in strawberry cropping systems.
Assuntos
Fragaria , Metarhizium , Microbiologia do Solo , Fragaria/microbiologia , Brasil , Dinamarca , Controle Biológico de VetoresRESUMO
In snakes that are known to be ambush predators, tail luring, in which the movement of a snake’s tail resembles that of a worm or insect larva and is used to attract prey, has emerged as a complementary hunting strategy. In certain species, some individuals may present a conspicuously bright colour at the tail tip, which eventually disappears with age. Some authors argue that the bright colour enhances the resemblance of the snake’s tail with a potential food item, increasing the success of capture. Here, we tested the influence of geographic variation, sex, and environmental factors on the probability that Common Lanceheads Bothrops jararaca (Wied-Neuwied, 1824) from southeastern Brazil were born with this contrasting tail tip and whether snakes retain this trait throughout adulthood. None of the predictors affected the probability of births with a contrasting tail tip. However, a higher proportion of individuals from the coastal populations retained this trait into adulthood. The absence of difference in the probability of being born with this trait indicates that there are other factors influencing tail tip colour, such as phylogenetic correlates, rather than intrinsic or environmental factors. A higher proportion of ectothermic prey in the diet of coastal populations may explain why this population retains tail luring throughout adulthood.
RESUMO
RESUMEN El palto es un cultivo muy importante, a nivel mundial y en Perú, siendo una plaga importante el ácaro Oligonychus punicae. El presente trabajo tuvo como objetivo determinar el efecto de diferentes niveles poblaciones del O. punicae, en el contenido de clorofila en hojas de palto y su impacto en su rendimiento e inferir un umbral económico y de intervención. Se utilizó un diseño completamente al azar, considerando 3 tratamientos con diferentes niveles poblacionales, correspondiente a los grados 2, 3 y mayor que 3. Se tomó un árbol como unidad experimental con 20 repeticiones por tratamiento, en donde se evaluó la población de ácaro en 4 hojas por árbol. Estas evaluaciones se realizaron con frecuencia semanal durante toda la campaña. Se midió el contenido de clorofila de las 4 hojas por árbol en cada tratamiento; asimismo, se evaluó el rendimiento en cada tratamiento (t ha-1). Los resultados mostraron que los diferentes grados de infestación estudiados: Grado 2 (1-10 ácaros/hoja), Grado 3 (11-25 ácaro/hoja), Grado 4 (26-50 ácaros/hoja) y Grado 5 (mayor a 50 ácaros/hoja) de O. punicae, no influyeron significativamente en los índices de clorofila en las hojas de palto. Además, se determinó que no existe correlación entre los diferentes grados de infestación de O. punicae con el rendimiento de palto. En el presente trabajo no se pudo determinar el umbral de acción para esta plaga y cultivo, ya que los niveles poblacionales estudiados no mostraron un impacto estadísticamente significativo sobre el rendimiento.
ABSTRACT Avocado is a very important crop worldwide, and in Peru, being a relevant pest the mite Oligonychus punicae. The aim of this paper was to determine the effect of different levels of O. punicae populations on the chlorophyll content in avocado leaves and its impact on their yield, and to infer an economic and intervention threshold. A completely randomized design was carried out, there were 3 treatments each with a different population level corresponding to grades 2, 3 and greater than 3. A tree was taken as a sampling unit with 20 replications per treatment, the mite population was evaluated in 4 leaves per tree. These evaluations were carried out on a weekly basis throughout the campaign. The chlorophyll content of the 4 leaves per tree was evaluated in each treatment, likewise the production in each treatment (t ha-1) was also evaluated. The results showed that the different degrees of infestation studied: Grade 2 (1 - 10 mites / leaf), Grade 3 (11-25 mites / leaf), Grade 4 (26- 50 mites / leaf) and Grade 5 (greater than 50 mites / leaf) of O. Hirst did not influence the chlorophyll indices in the avocado leaves. It was also determined that there is no correlation between the different degrees of infestation of O. punicae Hirst with the avocado yield. In the present work, the mite action threshold could not yet be determined since the population levels studied did not show a statistically significant impact on yield performance.
RESUMO
RESUMEN Los equinoideos comprenden uno de los grupos más influyentes en los ecosistemas arrecifales y litorales rocosos, debido a su importancia en las redes tróficas y reciclado de materia orgánica. En el Caribe colombiano existe un vacío de información sobre la ecología de estos organismos. La mayoría de los estudios se han centrado en la realización de inventarios y notas taxonómica, con el fin de estudiar la diversidad, la densidad poblacional y la distribución espacial de equinoideos regulares, en Isla Fuerte, Colombia. Se realizaron siete salidas de campo en Punta El Inglés, Latal y San Diego, entre noviembre de 2018 y septiembre de 2019. En cada localidad se realizaron censos visuales, aplicando la metodología de transecto lineal en banda (10 x 2 m). Se registraron 4.061 individuos representativo de seis especies, cinco géneros y cuatro familias. La especie que presentó mayores densidades fue Echinometra lucunter y, la de menor, Lytechinus variegatus. La riqueza de especies fue la misma para las tres localidades; sin embargo, Punta El Inglés presentó mayor diversidad, uniformidad y distintividad taxonómica promedio. El análisis de similitud de Bray-Curtis muestra una asociación entre San Diego y El Latal, mientras que Punta El Inglés forma una agrupación independiente. Los resultados de esta investigación representan una línea base para Isla Fuerte y puede ayudar a los gestores ambientales para sustentar herramientas y estrategias de manejo en este grupo de invertebrados.
ABSTRACT The echinoids constitute one of the most influential groups in reef and rocky coastal ecosystems due to their significance in trophic networks and organic matter recycling. In the Colombian Caribbean, there is a lack of information regarding the ecology of these organisms. Most studies have primarily focused on conducting inventories and taxonomic notes. To study the diversity, population density, and spatial distribution of regular echinoids in Isla Fuerte, Colombia. Seven field trips were conducted at Punta El Inglés, Latal, and San Diego between November 2018 and September 2019. Visual censuses were conducted in each locality using the linear belt transect methodology (10 x 2 m). 4,061 individuals were recorded, representing six species, five genera, and four families. The species with the highest densities was Echinometra lucunter, while the lowest was Lytechinus variegatus. Species richness was the same for all three localities; however, Punta El Inglés exhibited higher diversity, uniformity, and average taxonomic distinctness. The Bray-Curtis similarity analysis indicates an association between San Diego and El Latal, whereas Punta El Inglés forms an independent grouping. The results of this research represent a baseline for Isla Fuerte and can assist environmental managers in developing tools and management strategies for this group of invertebrates.
RESUMO
Trindade Island is an important wildlife refuge in the South Atlantic Ocean and hosts the largest nesting population of green turtles (Chelonia mydas) in Brazil, about which temporal ecological dynamics are still not well understood. The present study examines 23 years of nesting for green turtles at this remote island to evaluate annual mean nesting size (MNS) changes and post-maturity somatic growth rates. Our results show a significant decrease in annual MNS over the study; Whereas MNS during the first three consecutively monitored years (1993-1995) was 115.1 ± 5.4 cm, during the last three years (2014-2016) it was 111.2 ± 6.3 cm. There was no significant change in post-maturity somatic growth rate over the course of the study; the mean annual growth rate was 0.25 ± 0.62 cm/year. These findings suggest an increase in the relative proportion of smaller, presumptive neophyte nesters appearing in Trindade during the study period.
Assuntos
Tartarugas , Animais , Brasil , Animais Selvagens , Tamanho Corporal , Oceano Atlântico , Comportamento de NidaçãoRESUMO
Long-term land-use change impacts tropical bird communities through population-level and functional diversity effects from habitat loss, degradation and fragmentation, leading to land management and conservation challenges. Assessing the temporal impacts of land-use change on occupancy patterns, population change and functional traits of bird species in tropical areas is limited by the treatment of nondetections as true absences or artefacts of low sampling effort during and throughout years. With this in mind, we developed a novel Bayesian species occupancy framework to account for species absences to evaluate bird community changes in Palenque, Chiapas, Mexico, where there is opportunity for study given exceptional records of change across habitats from rainforest to urban centres. We created a novel dataset of population trends for 244 bird species over the years 1900 to 2020 from published short-term field studies, expert field notes and community science pages. Our results show that open area species had higher population increases than forest specialists over time, represented most evidently by the turnover of rainforest specialists for urban species. Modelled influence of functional traits displayed the importance of main habitat types, body mass and habitat and dietary breadth as factors that associated with bird population trends. On average, species with body masses <6.6 and > 948.4 g showed decreasing trends, while all other species showed increasing or stable trends. Our findings illuminate the value of accounting for species absences from several data sources to discover long-term species population trends and affiliated functional traits whose preservation requires conservation and land management action to protect bird ecosystem services. Primary forest conservation is key to maintaining populations of habitat and dietary specialists, such as small understorey insectivorous and large frugivorous species. Protecting rare natural savanna patches from conversion to cattle pasture is vital to prevent further extirpation of native granivores and to slow colonization by exotic and invasive species.
El cambio a largo plazo en el uso de la tierra impacta a las comunidades de aves tropicales a través de los efectos de la diversidad funcional y a nivel de la población debido a la pérdida, degradación y fragmentación del hábitat, lo que lleva a desafíos de gestión y conservación de la tierra. La evaluación de los impactos temporales del cambio de uso de la tierra en los patrones de ocupación, el cambio de población y los rasgos funcionales de las especies de aves en áreas tropicales enfrenta limitaciones al considerar el tratamiento de las no detecciones como ausencias verdaderas o artefactos de bajo esfuerzo de muestreo durante el año y los años. La evaluación de los impactos temporales del cambio de uso de la tierra en los patrones de ocupación, el cambio de población y las características funcionales de las especies de aves en áreas tropicales está limitada por el tratamiento de las no detecciones como verdaderas ausencias o artefactos de bajo esfuerzo de muestreo durante y a lo largo de los años. Con esto en mente, desarrollamos un marco bayesiano novedoso de ocupación de especies para dar cuenta de las ausencias de especies para evaluar los cambios en la comunidad de aves en Palenque, Chiapas, México, donde existe la oportunidad de estudiar dados los registros excepcionales de cambios en los hábitats, desde la selva tropical hasta los centros urbanos. Creamos un nuevo conjunto de datos de tendencias de población para 244 especies de aves durante los años 1900 a 2020 a partir de estudios de campo a corto plazo publicados, notas de campo de expertos y páginas de ciencia comunitaria. Nuestros resultados muestran que las especies de áreas abiertas tuvieron aumentos de población más altos que los especialistas forestales a lo largo del tiempo, representado más evidentemente por la rotación de especialistas de bosques tropicales por especies urbanas. La influencia modelada de los rasgos funcionales mostró la importancia de los principales tipos de hábitat, la masa corporal y el hábitat y la amplitud de la dieta como factores asociados con las tendencias de la población de aves. En promedio, las especies con masas corporales <6,6 g y >948,4 g mostraron tendencias decrecientes, mientras que todas las demás especies mostraron tendencias crecientes o estables. Nuestros hallazgos iluminan el valor de contabilizar las ausencias de especies de varias fuentes de datos para descubrir tendencias de población de especies a largo plazo y rasgos funcionales afiliados cuya preservación requiere acción de conservación y manejo de la tierra para proteger los servicios ecosistémicos de las aves. La conservación de los bosques primarios es clave para mantener las poblaciones de especialistas en hábitat y dieta, como las especies insectívoras pequeñas del sotobosque y las especies frugívoras grandes. Proteger los raros parches naturales de sabana de la conversión en pastos para ganado es vital para evitar una mayor extirpación de los granívoros nativos y para retrasar la colonización por especies invasoras.
Assuntos
Biodiversidade , Ecossistema , Animais , Bovinos , Teorema de Bayes , México , Florestas , Aves , Conservação dos Recursos NaturaisRESUMO
ABSTRACT Temperature affects the body size of animals, which is an important trait in natural and sexual selection. Insects do not have complex mechanisms of temperature control, thus temperature changes affect their life aspects, from enzymatic reactions to behavior. The amount of fat stored by insects is also influenced by temperature and constitutes a tissue with biosynthetic and metabolic activity, acting as an energy reservoir. We assessed the effect of environmental temperature due to elevation and seasonal temperature variations on body size and condition of two dung beetles species: Canthon rutilans cyanescens and Dichotomius sericeus (Coleoptera: Scarabaeinae). Both species are abundant in southern Brazilian forests, but they differ in habits: the first is a diurnal roller whereas the later is a nocturnal tunneler. Summer months and sites with lower elevations and higher temperatures presented larger C. rutilans cyanescens. A linear relationship exists between body size and soil temperatures, whereas the temperature positively influences the body length. Furthermore, C. rutilans cyanescens from cooler sites had more body fat. Individuals of D. sericeus were also larger in summer months, however, we did not find differences in the proportion of fat or a relation between body size and temperature. Thus, the body size of dung beetle species varies in relation to temporal factors, as both species are larger in summer. More interesting was to observe that the species with a diurnal habit, even though smaller in colder places, has a higher proportion of fat, which indicates an evolutionary response to environmental pressure.
RESUMO
Ceratitis capitata (Wiedemann) and Drosophila suzukii (Matsumura) are two severe invasive pests widespread in all Argentinean fruit-producing regions. Both coexist with the Neotropical pest Anastrepha fraterculus (Wiedemann) in northern Argentina. The northwestern region shelters major soft fruit and Citrus producing and exporting industries, which are heavily affected by these dipterans. Eco-friendly strategies are under assessment in Argentina. This study mainly assessed D. suzukii, C. capitata, and A. fraterculus temporal abundance variations and their natural parasitism levels on a 1.5-ha-patch of feral peach trees within a disturbed secondary subtropical rainforest of northwestern Argentina. Fly puparia were mainly collected from the soil under fallen peach. Sampling was performed over three peach fruiting seasons. The most abundant pest species was C. capitata. Drosophila suzukii was only found in the last collecting period, but outnumbered A. fraterculus. Natural parasitism distinctly affected the temporal abundance of these dipterans: it significantly depressed C. capitata abundance in last sampling weeks, it did not substantially affect D. suzukii abundance, but it increased synchronously with the increase in the A. fraterculus abundance. Parasitism on C. capitata was mostly exerted by a combination of both a cosmopolitan pupal and a native larval parasitoid, while A. fraterculus was mainly parasitized by two indigenous larval parasitoids. Only three resident pupal parasitoids were associated with D. suzukii, of which the cosmopolitan Pachycrepoideus vindemiae Rondani (Hymenoptera: Pteromalidae) was the most significant. Data on the resident parasitoid impact are relevant for designing biocontrol strategies in noncrop habitats.
Assuntos
Ceratitis capitata , Himenópteros , Tephritidae , Animais , Espécies Introduzidas , Drosophila , Pupa , Controle Biológico de VetoresRESUMO
Rhinoclemmys punctularia punctularia is the only turtle of the family Geoemydidae with part of its range in Brazil. The species is semi-aquatic and widely distributed across the Amazon basin but is still poorly studied. We evaluated aspects of the population structure, habitat use, seasonal activity, and diet of the species during one year, from the beginning of the rainy season to the end of the dry season, in two headwater localities in the Tocantins and Tapajós river basins, in the state of Pará, Brazil. We captured 45 individuals, 14 in the Tocantins basin and 31 in the Tapajós basin. The size-class frequency distributions of captured individuals did not differ between the two samples. The turtles were most frequently captured in first-order streams, followed by lentic (third-order dammed streams) and second-order streams. The capture rate did not vary significantly between sampling periods (start and peak of the rainy season; start and end of the dry season). The trapping effort to capture a single individual was much higher in the Tapajós basin (1,215 trap-hours) than in the Tocantins basin (136 trap-hours). Overall, the low capture rates confirm the secretive nature of the species in Amazonia and its apparent rarity. The individuals analyzed in this study consumed mainly plants.(AU)
Rhinoclemmys punctularia punctularia é o único quelônio da família Geoemydidae com parte de sua distribuição no Brasil. A espécie é semi-aquática e amplamente distribuída na bacia amazônica, mas ainda é pouco estudada. Avaliamos aspectos da estrutura populacional, uso do habitat, atividade sazonal e dieta da espécie ao longo de um ano, desde o início da estação chuvosa até o final da estação seca, em duas localidades de cabeceira nas bacias dos rios Tocantins e Tapajós, no estado do Pará, Brasil. Capturamos 45 indivíduos: 14 na bacia do Tocantins e 31 na bacia do Tapajós. A distribuição de frequências por classe de tamanho dos indivíduos capturados não diferiu entre as duas amostras. Os quelônios foram mais frequentemente capturados em riachos de primeira ordem, seguidos por riachos lênticos (riachos de terceira ordem represados) e de segunda ordem. A taxa de captura não variou significativamente entre os períodos de amostragem (início e pico da estação chuvosa; início e fim da estação seca). O esforço de armadilhagem para capturar um único indivíduo foi muito maior na bacia do Tapajós (1.215 horas-armadilha) do que na bacia do Tocantins (136 horas-armadilha). No geral, as baixas taxas de captura confirmam a natureza discreta da espécie na Amazônia e sua aparente raridade. Os indivíduos analisados neste estudo consumiram principalmente plantas.(AU)
Assuntos
Tartarugas , Biodiversidade , Distribuição Animal , Brasil , Ecossistema AmazônicoRESUMO
The temperatures at which eggs of crocodilians are incubated plays an important role in embryo survival, rate of embryonic development and sex definition. The aim of this study was to assess the nest temperatures of an American crocodile (Crocodylus acutus) population on the central coast of Oaxaca state in Mexico. The fieldwork was carried out from February to June 2018 at Palmasola Lagoon, Oaxaca. Ten natural nests of C. acutus were carefully excavated to determine clutch size. When putting the eggs back in the nests, we placed a data logger in the center of the egg mass to determine the temperature parameters in the nest chamber environment, as well as the variation in temperature during the incubation period. All nests were revisited to count the number of hatched eggs (NHE) and to determine the hatching success (HS), along with the duration of the incubation period (IP). Hatching success was 89.04%. The mean clutch size in the American crocodile nests was 30.7 ± 7.83 eggs (ranging from 17 to 46 eggs), and the mean incubation period was 77.6 ± 5.89 days. The mean nest incubation temperature throughout the reproductive season was significantly different among nests. Based on the average temperature during the middle third of the incubation period, the nests should have produced both sexes, but with a higher proportion of males. This study tried to elucidate the impact of nest temperatures during the incubation period on embryo survival, as well as hatchling sex ratio in a local climate on the central coast of Oaxaca.
Assuntos
Jacarés e Crocodilos/fisiologia , Tamanho da Ninhada , Ecossistema , Temperatura , Animais , Feminino , Masculino , México , Razão de MasculinidadeRESUMO
BACKGROUND: Diseases transmitted by invasive Aedes aegypti and Aedes albopictus mosquitoes are public health issues in the tropics and subtropics. Understanding the ecology of mosquito vectors is essential for the development of effective disease mitigation programs and will allow for accurate predictions of vector occurrence and abundance. Studies that examine mosquito population dynamics are typically focused on female presence or total adult captures without discriminating the temporal and spatial distribution of both sexes. METHODS: We collected immature and adult mosquitoes bimonthly for 2 years (2018-2019) in the Medellín Botanical Garden. Collection sites differed in proximity to buildings and nearby vegetation, and were classified by their overhead vegetation cover. We used linear mixed models (LMMs) and Spatial Analysis by Distance Indices (SADIE) to assess the spatial distribution of Ae. aegypti and Ae. albopictus. Using our Ae. albopictus captures exclusively, we assessed (1) the spatial and temporal distribution of males and females using SADIE and a generalized linear mixed model (GLMM), (2) the relationship between climatic variables/vegetation coverage and adult captures using GLMMs and LMMs, and (3) the correlation of male and female size in relation to climatic variables and vegetation coverage using LMMs. RESULTS: Spatial analysis showed that Ae. aegypti and Ae. albopictus were distributed at different locations within the surveilled area. However, Ae. albopictus was the predominant species in the park during the study period. Adult Ae. albopictus captures were positively correlated with precipitation and relative humidity, and inversely correlated with temperature and wind speed. Moreover, we observed a spatial misalignment of Ae. albopictus males and females-the majority of males were located in the high vegetation coverage sites, while females were more evenly distributed. We observed significant associations of the size of our adult Ae. albopictus captures with precipitation, temperature, and wind speed for both sexes and found that overhead vegetation cover influenced male size, but observed no effect on female size. CONCLUSIONS: Our work elucidates the differential dynamics of Ae. albopictus males and females, which is pivotal to develop accurate surveillance and the successful establishment of vector control programs based on the disruption of insect reproduction.
Assuntos
Aedes/crescimento & desenvolvimento , Aedes/fisiologia , Animais , Colômbia , Feminino , Masculino , Dinâmica Populacional , Análise Espacial , TemperaturaRESUMO
O aumento do conhecimento sobre a ecologia populacional das espécies de quelônios amazônicos é essencial para a recuperação e manutenção dos estoques naturais desses répteis. Neste estudo foi avaliada a influência de fatores hidroclimáticos sobre parâmetros populacionais e a condição corporal de Podocnemis expansa (Schweigger, 1812) em um trecho do Rio Formoso, sudeste da Amazônia brasileira, caracterizado pelo intenso uso das águas superficiais na irrigação de culturas agrícolas. O trabalho de campo ocorreu em três campanhas realizadas entre o final de julho e início de agosto dos anos de 2016, 2017 e 2018, totalizando um esforço amostral de 205 horas. Os indivíduos foram capturados por meio dos métodos de arrasto de rede, pesca com anzol e rede de espera; e os dados hidroclimáticos obtidos no site da Agência Nacional das Águas - ANA. Um total de 466 espécimes foi capturado e marcado, incluindo 47 machos adultos, 76 fêmeas adultas e 343 juvenis- revelando-se uma população composta predominantemente por juvenis (73,60%) e com razão sexual funcional desviada para as fêmeas (0,62:1). A redução no número de indivíduos das classes de tamanhos maiores e melhores condições corporais estiveram associadas, respectivamente, a uma maior vazão média do rio na estação seca e ao aumento da vazão no período chuvoso. Estudos futuros de longo prazo devem buscar aprofundar os conhecimentos sobre como fatores hidroclimáticos e as atividades agrícolas desenvolvidas na região afetam a demografia da espécie.
Evaluation of the influence of hydroclimatic factors on the population structure of Podocnemis expansa (Testudines: Podocnemididae) in Formoso River, southeastern Brazilian Amazon. It is essential to have more knowledge about the population ecology of Amazonian chelonian species in order to recover and maintain the natural stocks of these reptiles. This study assessed the influence of hydroclimatic factors on population parameters and the body condition of Podocnemis expansa (Schweigger, 1812) in a specific region of Formoso River, in the southeast of Brazilian Amazon rainforest, where there is an intense use of surface water for irrigation of agricultural crops. The fieldwork took place in three campaigns carried out between the end of July and the beginning of August in the years 2016, 2017 and 2018, with a total sample effort of 205 hours. The individuals were captured using the methods of net trawling, hook fishing and waiting net; and the hydroclimatic data obtained from the website of the Agência Nacional de Águas - ANA. A total of 466 specimens were captured and tagged, being 47 adult males, 76 adult females and 343 juveniles, demonstrating a population composed mostly of juveniles (73.60%) and with a deviated functional sex ratio for females (0.62:1). The reduction in the number of individuals of larger sizes and better body conditions were associated, respectively, with higher river flow average in the dry season and an increase in flow during the rainy period. Future long-term studies are necessary to deepen the knowledge about how hydroclimatic factors and agricultural activities developed in the region affect the demography of the species.
Assuntos
Animais , Ecologia , Irrigação Agrícola , Processos Climáticos , Tartarugas/crescimento & desenvolvimento , Tartarugas/fisiologia , RépteisRESUMO
ABSTRACT Evaluation of the influence of hydroclimatic factors on the population structure of Podocnemis expansa (Testudines: Podocnemididae) in Formoso River, southeastern Brazilian Amazon. It is essential to have more knowledge about the population ecology of Amazonian chelonian species in order to recover and maintain the natural stocks of these reptiles. This study assessed the influence of hydroclimatic factors on population parameters and the body condition of Podocnemis expansa (Schweigger, 1812) in a specific region of Formoso River, in the southeast of Brazilian Amazon rainforest, where there is an intense use of surface water for irrigation of agricultural crops. The fieldwork took place in three campaigns carried out between the end of July and the beginning of August in the years 2016, 2017 and 2018, with a total sample effort of 205 hours. The individuals were captured using the methods of net trawling, hook fishing and waiting net; and the hydroclimatic data obtained from the website of the Agência Nacional de Águas - ANA. A total of 466 specimens were captured and tagged, being 47 adult males, 76 adult females and 343 juveniles, demonstrating a population composed mostly of juveniles (73.60%) and with a deviated functional sex ratio for females (0.62:1). The reduction in the number of individuals of larger sizes and better body conditions were associated, respectively, with higher river flow average in the dry season and an increase in flow during the rainy period. Future long-term studies are necessary to deepen the knowledge about how hydroclimatic factors and agricultural activities developed in the region affect the demography of the species.
RESUMO O aumento do conhecimento sobre a ecologia populacional das espécies de quelônios amazônicos é essencial para a recuperação e manutenção dos estoques naturais desses répteis. Neste estudo foi avaliada a influência de fatores hidroclimáticos sobre parâmetros populacionais e a condição corporal de Podocnemis expansa (Schweigger, 1812) em um trecho do Rio Formoso, sudeste da Amazônia brasileira, caracterizado pelo intenso uso das águas superficiais na irrigação de culturas agrícolas. O trabalho de campo ocorreu em três campanhas realizadas entre o final de julho e início de agosto dos anos de 2016, 2017 e 2018, totalizando um esforço amostral de 205 horas. Os indivíduos foram capturados por meio dos métodos de arrasto de rede, pesca com anzol e rede de espera; e os dados hidroclimáticos obtidos no site da Agência Nacional das Águas - ANA. Um total de 466 espécimes foi capturado e marcado, incluindo 47 machos adultos, 76 fêmeas adultas e 343 juvenis- revelando-se uma população composta predominantemente por juvenis (73,60%) e com razão sexual funcional desviada para as fêmeas (0,62:1). A redução no número de indivíduos das classes de tamanhos maiores e melhores condições corporais estiveram associadas, respectivamente, a uma maior vazão média do rio na estação seca e ao aumento da vazão no período chuvoso. Estudos futuros de longo prazo devem buscar aprofundar os conhecimentos sobre como fatores hidroclimáticos e as atividades agrícolas desenvolvidas na região afetam a demografia da espécie.
RESUMO
O aumento do conhecimento sobre a ecologia populacional das espécies de quelônios amazônicos é essencial para a recuperação e manutenção dos estoques naturais desses répteis. Neste estudo foi avaliada a influência de fatores hidroclimáticos sobre parâmetros populacionais e a condição corporal de Podocnemis expansa (Schweigger, 1812) em um trecho do Rio Formoso, sudeste da Amazônia brasileira, caracterizado pelo intenso uso das águas superficiais na irrigação de culturas agrícolas. O trabalho de campo ocorreu em três campanhas realizadas entre o final de julho e início de agosto dos anos de 2016, 2017 e 2018, totalizando um esforço amostral de 205 horas. Os indivíduos foram capturados por meio dos métodos de arrasto de rede, pesca com anzol e rede de espera; e os dados hidroclimáticos obtidos no site da Agência Nacional das Águas - ANA. Um total de 466 espécimes foi capturado e marcado, incluindo 47 machos adultos, 76 fêmeas adultas e 343 juvenis- revelando-se uma população composta predominantemente por juvenis (73,60%) e com razão sexual funcional desviada para as fêmeas (0,62:1). A redução no número de indivíduos das classes de tamanhos maiores e melhores condições corporais estiveram associadas, respectivamente, a uma maior vazão média do rio na estação seca e ao aumento da vazão no período chuvoso. Estudos futuros de longo prazo devem buscar aprofundar os conhecimentos sobre como fatores hidroclimáticos e as atividades agrícolas desenvolvidas na região afetam a demografia da espécie.(AU)
Evaluation of the influence of hydroclimatic factors on the population structure of Podocnemis expansa (Testudines: Podocnemididae) in Formoso River, southeastern Brazilian Amazon. It is essential to have more knowledge about the population ecology of Amazonian chelonian species in order to recover and maintain the natural stocks of these reptiles. This study assessed the influence of hydroclimatic factors on population parameters and the body condition of Podocnemis expansa (Schweigger, 1812) in a specific region of Formoso River, in the southeast of Brazilian Amazon rainforest, where there is an intense use of surface water for irrigation of agricultural crops. The fieldwork took place in three campaigns carried out between the end of July and the beginning of August in the years 2016, 2017 and 2018, with a total sample effort of 205 hours. The individuals were captured using the methods of net trawling, hook fishing and waiting net; and the hydroclimatic data obtained from the website of the Agência Nacional de Águas - ANA. A total of 466 specimens were captured and tagged, being 47 adult males, 76 adult females and 343 juveniles, demonstrating a population composed mostly of juveniles (73.60%) and with a deviated functional sex ratio for females (0.62:1). The reduction in the number of individuals of larger sizes and better body conditions were associated, respectively, with higher river flow average in the dry season and an increase in flow during the rainy period. Future long-term studies are necessary to deepen the knowledge about how hydroclimatic factors and agricultural activities developed in the region affect the demography of the species.(AU)
Assuntos
Animais , Tartarugas/crescimento & desenvolvimento , Processos Climáticos , Irrigação Agrícola , Ecologia , Tartarugas/fisiologia , RépteisRESUMO
Fire is one of the main disturbance agents globally and one of the main threats on the Brazilian cerrado (Neotropical savanna), acting as environmental filter for species selection. Individuals of Morpho helenor achillides (C. Felder and R. Felder, 1867) and M. menelaus coeruleus (Perry, 1810) were captured weekly using entomological nets and fruit-baited traps over a 36-mo period (from May 2005 to April 2008). The present study analyzed the impact of a fire event in both the above species, showing that they present different responses to this disturbance. Morpho helenor was persistent as adults during the dry season, which could fly away from the flames to neighbor unburned areas and return after dry-season bushfires. Conversely, Morpho menelaus persists only as caterpillars during the dry season, which are unable to escape from the flames resulting in high impacts on local population (the species was not captured up to the end of this study). In addition, based on host plant species reported in the literature, we assigned a broader host plant range to M. helenor, suggesting that a generalist diet could help in the maintenance of individuals during the dry season, as they have more options to breed all year round. A better understanding of the temporal dynamics of adult and immature stages could help predict the amplitude of the impacts of dry season fire events on insects, especially when preventive fires are strategically used inside protected areas.
Assuntos
Borboletas , Animais , Brasil , Ecossistema , Pradaria , Plantas , Estações do AnoRESUMO
As part of the Deepwater Horizon Oil Spill Natural Resource Damage Assessment in the Gulf of Mexico, we conducted a large passive acoustic survey across the eastern Gulf continental shelf edge to assess impacts to sperm whale population. In the months immediately after the spill, sperm whale occurrence was significantly higher in areas closest to the spill. Over the following seasons in 2010-2011, we documented cyclical patterns of decreased and increased occurrence suggesting that this population exhibits a seasonal occurrence pattern in the region, with seasonal movements to other regions, and not likely directly influenced by the oil spill. Unfortunately, a lack of adequately scaled, pre-spill data on sperm whales, along with limitations on the survey duration constrain our ability to infer spill-related changes in sperm whale occurrence. However, our study establishes post-disaster baseline data for continued monitoring, and an expanded study design could provide a model for continued monitoring.
Assuntos
Poluição por Petróleo , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Golfo do México , Estações do Ano , Cachalote , Poluentes Químicos da Água/análiseRESUMO
Edge effects alter insect biodiversity in several ways. However, we still have a limited understanding on simultaneous responses of ecological populations and assemblages to ecotones, especially in human modified landscapes. We analyze edge effects on dung beetle populations and assemblages between livestock pastures and native temperate forests (Juniperus and pine-oak forests (POFs)) to describe how species abundances and assemblage parameters respond to edge effects through gradients in forest-pasture ecotones. In Juniperus forest 13 species avoided the ecotones: six species showed greater abundance in forest interior and seven in pasturelands, while the other two species had a neutral response to the edge. In a different way, in POF we found five species avoiding the edge (four with greater abundance in pastures and only one in forest), two species had a neutral response, and two showed a unimodal pattern of abundance near to the edge. At the assemblage level edge effects are masked, as species richness, diversity, functional richness, functional evenness, and compositional incidence dissimilarity did not vary along forest-pasture ecotones. However, total abundance and functional divergence showed higher values in pastures in one of the two sampling localities. Also, assemblage similarity based on species' abundance showed a peak near to the edge in POF. We propose that conservation efforts in human-managed landscapes should focus on mitigating current and delayed edge effects. Ecotone management will be crucial in livestock dominated landscapes to conserve regional biodiversity and the environmental services carried out by dung beetles.