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1.
J Fish Biol ; 105(1): 378-381, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757771

RESUMO

Despite being a heavily fished species, little is known about the movements of silky sharks (Carcharhinus falciformis). In this study, we report the longest (in duration and distance traveled) and most spatially extensive recorded migration for a silky shark. This shark, tagged with a fin-mount satellite transmitter at the Galapagos Islands, traveled >27,666 km over 546 days, making two westerly migrations into international waters as far as 4755 km from the tagging location. These extensive movements in an area with high international fishing effort highlights the importance of understanding silky shark migrations to inform management practices.


Assuntos
Migração Animal , Tubarões , Animais , Oceano Pacífico , Equador
2.
Glob Chang Biol ; 30(4): e17278, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38655695

RESUMO

The increasing frequency and severity of human-caused fires likely have deleterious effects on species distribution and persistence. In 2020, megafires in the Brazilian Pantanal burned 43% of the biome's unburned area and resulted in mass mortality of wildlife. We investigated changes in habitat use or occupancy for an assemblage of eight mammal species in Serra do Amolar, Brazil, following the 2020 fires using a pre- and post-fire camera trap dataset. Additionally, we estimated the density for two naturally marked species, jaguars Panthera onca and ocelots Leopardus pardalis. Of the eight species, six (ocelots, collared peccaries Dicotyles tajacu, giant armadillos Priodontes maximus, Azara's agouti Dasyprocta azarae, red brocket deer Mazama americana, and tapirs Tapirus terrestris) had declining occupancy following fires, and one had stable habitat use (pumas Puma concolor). Giant armadillo experienced the most precipitous decline in occupancy from 0.431 ± 0.171 to 0.077 ± 0.044 after the fires. Jaguars were the only species with increasing habitat use, from 0.393 ± 0.127 to 0.753 ± 0.085. Jaguar density remained stable across years (2.8 ± 1.3, 3.7 ± 1.3, 2.6 ± 0.85/100 km2), while ocelot density increased from 13.9 ± 3.2 to 16.1 ± 5.2/100 km2. However, the low number of both jaguars and ocelots recaptured after the fire period suggests that immigration may have sustained the population. Our results indicate that the megafires will have significant consequences for species occupancy and fitness in fire-affected areas. The scale of megafires may inhibit successful recolonization, thus wider studies are needed to investigate population trends.


A crescente frequência e gravidade dos incêndios causados pelo homem provavelmente terão efeitos deletérios na distribuição e persistência das espécies. Em 2020, mega incêndios no Pantanal brasileiro queimaram 43% do bioma e resultaram na mortalidade em massa da vida selvagem. Nós investigamos mudanças no uso ou ocupação do habitat para uma comunidade de oito espécies de mamíferos na Serra do Amolar, Brasil, após os incêndios de 2020, usando um conjunto de dados de armadilhas fotográficas instaladas no período pré e pós­fogo. Além disso, estimamos a densidade de duas espécies naturalmente marcadas, a onça­pintada Panthera onca e a jaguatirica Leopardus pardalis. Das oito espécies, seis (a jaguatirica, o cateto Dicotyles tajacu, o tatu­canastra Priodontes maximus, a cutia Dasyprocta azarae, o veado mateiro Mazama americana e a anta Tapirus terrestris) tiveram ocupação reduzida após os incêndios, e uma teve uso de habitat estável (a onça­parda, Puma concolor). O tatu­canastra apresentou o declínio mais acentuado na ocupação após os incêndios de 0,431 ± 0,171 para 0,077 ± 0,044. A onça­pintada foi a única espécie com uso crescente de habitat, de 0,393 ± 0,127 para 0,753 ± 0,085. A densidade da onça­pintada permaneceu estável ao longo dos anos (2,8 ± 1,3, 3,7 ± 1,3, 2,6 ± 0,85/100 km2), enquanto a densidade da jaguatirica aumentou de 13,9 ± 3,2 para 16,1 ± 5,2/100 km2. No entanto, o baixo número de onças­pintadas e jaguatiricas recapturadas após o período do fogo sugere que a imigração pode ter sustentado as populações. Nossos resultados indicam que os mega incêndios terão consequências significativas para a ocupação e resiliência das espécies nas áreas afetadas pelo fogo. A escala dos mega incêndios pode inibir uma recolonização bem­sucedida, pelo que são necessários estudos mais amplos para investigar as tendências populacionais.


Assuntos
Ecossistema , Animais , Brasil , Mamíferos/fisiologia , Dinâmica Populacional , Incêndios , Densidade Demográfica , Incêndios Florestais
3.
Environ Res ; 251(Pt 2): 118621, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492834

RESUMO

Pollution and bycatch are two of the main threats for cetaceans worldwide. These threats are exacerbated for nearshore species particularly for those in regions with intense industrial and fishing activities. Burmeister's porpoise is endemic to South America, has a Near Threatened conservation status because of long-term mortality in fisheries. Burmeister's porpoise occur in Mejillones Bay, northern Chile, a hot spot for heavy metals pollution from the mining industry and an intense industrial and artisanal purse-seine fishing area. From 2018 to 2021, we conducted systematic marine surveys to assess the abundance, distribution and habitat use of Burmeister's porpoises. We responded to stranding reports from 2018 to 2022, and necropsied nine individuals. From five of these, we analyzed the metal concentrations (As, Cd, Cr, Cu, Pb, Hg, Se and Zn) in muscle and skin tissues. Results showed an abundance of 76.17 individuals (CV = 25.9%) and an average density of 0.45 individuals/km2 (CV = 26%). Burmeister's porpoises were observed year round, 22.2% were mother-calf pairs present in austral summer at an average of 90.6 m depth in the southwestern bound of the bay. Two-thirds of stranded specimens died due to bycatch and one died due to bottlenose dolphin (Tursiops truncatus) attack. We report a dead Burmeister's porpoise positive for avian flu virus A (H5N1). Metals analyzed were found in muscle and skin tissues of stranded Burmeister's porpoises in the following order (Zn > Cu > Cr > As > Hg > Pb > Cd). Although we could not assess pollution as a cause of mortality, Cr, As and Pb concentrations exceeded the concentrations found in other porpoises species worldwide. We conclude that bycatch and pollution as the main threats for Burmeister's porpoise survival in northern Chile. Future studies should investigate the use of acoustic deterrent alarms to mitigate the bycatch in the bay and consider the Burmeister's porpoise as a sentinel species of pollution in northern Chilean coast.


Assuntos
Baías , Monitoramento Ambiental , Toninhas , Animais , Chile , Metais Pesados/análise , Poluentes Químicos da Água/análise , Pesqueiros
4.
Biota Neotrop. (Online, Ed. ingl.) ; 24(1): e20231518, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1557168

RESUMO

Abstract Floating structures, both natural and artificial, attract fish by providing shelter, feeding areas, and nesting sites. Occupancy can be either more permanent, leading to a gradual gathering of the assembly, or transient, occurring randomly. The ability of an attractor to hold a fish assemblage may depend on the availability of habitat resources in the environment. New artificial attractors are more valuable when natural ones are scarce. Additionally, fish characteristics play a role; young and small fishes may need new habitat for shelter more than adult fish. As aquatic herbaceous areas are abundant during high water, coinciding with the period of fish reproduction, they are particularly relevant for juveniles. We constructed fish attractors composed of natural materials to investigate the structure of fish assemblages during the flood of an Amazonian floodplain lake. Our aim was to test the hypothesis that assembly processes during the flood period would be random, with a predominance of juveniles in the attractors. We collected fish at intervals of 5, 15, and 30 days, resulting in 39 observations, and classified them as either adult or juvenile. Species composition was compared among treatments using Principal Coordinates Analysis (PCoA). The assembly process was tested through species co-occurrence patterns employing null models and the C-score index. The proportion of juveniles and adults was compared using a Chi-square test. Species composition remained consistent throughout the experiment. The assembly was random, with a prevalence of juveniles, possibly serving only as temporary shelter and feeding areas. Our study contributes to understanding the role of habitat availability for floodplain fishes during high waters. The results suggest that floating attractors and new habitats may be more valuable for the juveniles than adult fish and can be used as a management strategy for population recovery, especially when floating herbaceous habitats are scarce.


Resumo As estruturas flutuantes, naturais ou artificiais, atraem os peixes, fornecendo abrigo, áreas de alimentação e locais de nidificação. A ocupação pode ser mais permanente, resultando em um recolhimento gradativo da assembleia, ou transitória, ocorrendo aleatoriamente. A capacidade de um atrator de manter uma assembleia de peixes pode depender da disponibilidade de recursos de habitat no ambiente. Novos atratores artificiais são mais valiosos quando os naturais são escassos. Além disso, as características dos peixes desempenham um papel, já que peixes jovens e pequenos podem necessitar de novos habitats como abrigo mais do que peixes adultos. Como as áreas com herbáceas aquáticas são abundantes durante as cheias, coincidindo com o período de reprodução dos peixes, elas são especialmente relevantes para peixes juvenis. Construímos atratores de peixes compostos de material natural para investigar a estrutura das assembleias de peixes durante a cheia de um lago de várzea amazônico, a fim de testar a hipótese de que durante o período de cheia, os processos de montagem seriam aleatórios e com predominância de juvenis nos atratores. Os peixes foram coletados em intervalos de 5, 15 e 30 dias, resultando em 39 observações, e classificados como adultos ou juvenis. A composição de espécies foi comparada entre os tratamentos usando uma Análise de Coordenadas Principais (PCoA). O processo de montagem foi testado por meio de padrões de coocorrência de espécies usando modelos nulos e o índice C-score. A proporção de jovens e adultos foi comparada usando um teste Qui-quadrado. A composição de espécies permaneceu a mesma ao longo do experimento. A montagem da assembleia foi aleatória com prevalência de juvenis nos atratores, que possivelmente serviam apenas como abrigo temporário e áreas de alimentação. Nosso estudo contribui para entender o papel da disponibilidade de novos habitats para peixes de várzea durante a cheia. Os resultados sugerem que atratores flutuantes e novos habitats podem ser mais valiosos para os peixes jovens do que para adultos e podem ser usados como estratégia de manejo para a recuperação populacional, especialmente quando habitats de herbáceas flutuantes são escassos.

5.
Animals (Basel) ; 13(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37958070

RESUMO

This study presents the first successful capture using GPS tagging of a jaguar (Panthera onca) using a minimally invasive capture system (MICS). We used snare-foot traps and a MICS during two capture campaigns in a fragment of Atlantic Forest in southeastern Brazil. The specimen disarmed snares on different occasions, and capture was only possible with the MICS. The captured jaguar, an estimated 16-year-old adult male, was monitored using a GPS Vertex Plus Iridium collar with an optimal performance of 86% in expected locations. The jaguar's home range (659 km2 by MPC and 174 km2 by 95%K) was within the observed range for the species and the animal was primarily maintained in protected areas. The habitat types most frequently used were native grassland (27.2% of 4798 fixes), marsh (24.8%), and dense lowland forest (24.7%). The use of a MICS for trapping jaguars is a promising technique that shows advantages in terms of efficiency, selectivity, portability, reduced potential risk of injury to animals or trappers, and animal stress compared to other capture methods used for the species.

6.
Neotrop. ichthyol ; 21(1): e220103, 2023. mapas, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1418883

RESUMO

Data obtained by direct observation of organisms in their natural habitats can provide valuable contributions regarding intra- and inter-specific interactions, as well as spatial distribution and trophic relationships. However, relatively few such data are available for the Neotropical ichthyofauna relative to the great species diversity of this region. We present data on the ichthyofauna in karst environments of the Serra da Bodoquena, Upper Paraguay River basin regarding their categorization into functional trophic groups. We used direct observations that focused on the most frequent feeding tactics and their spatial (vertical and horizontal) distribution in the channel. We observed 83 fish species in 17 functional trophic groups. The greatest species richness was concentrated in the Characidae and Loricariidae in the categories Diurnal Backwater Drift Feeders and Grazers, respectively. Regarding horizontal depth stratification, we found a positive relationship between the association of small fish with the shallow marginal habitats. This work represents a contribution to a region known for its high tourist potential and to the important diversity of the entire ichthyofauna of the Upper Paraguay basin region that requires proper conservation strategies for sustaining these species.(AU)


Dados obtidos pela observação direta dos organismos em seus hábitats naturais podem fornecer valiosas contribuições com relação a interações intra e inter-específicas, além de distribuição espacial e relações tróficas. Entretanto, relativamente poucos dados estão disponíveis no que diz respeito à ictiofauna neotropical dada à grande diversidade dessa região. Apresentamos dados sobre a ictiofauna em ambientes cársticos da Serra da Bodoquena, bacia do alto rio Paraguai e a categorização das mesmas em grupos tróficos funcionais baseada em observações diretas relacionadas às táticas alimentares mais frequentes e à sua distribuição espacial (vertical e horizontal) no canal. Assim sendo, observamos 83 espécies de peixes alocadas em 17 grupos tróficos funcionais. A maior riqueza de espécies concentrou-se nas famílias Characidae e Loricariidae, abrangendo as categorias Catadores Diurnos de Itens Arrastados pela Corrente e Pastadores, respectivamente. Com relação à estratificação horizontal, encontramos a relação positiva entre a associação de peixes de pequeno porte com relação aos hábitats marginais. Esse trabalho representa uma contribuição a uma região conhecida pelo seu alto potencial turístico e à importante diversidade da ictiofauna da região da bacia do alto Paraguai que requer estratégias de conservação adequadas para sustentar essas espécies.(AU)


Assuntos
Animais , Cadeia Alimentar , Comportamento Alimentar , Peixes/fisiologia , Brasil , Ecossistema , Níveis Tróficos
7.
J. Anim. Behav. Biometeorol ; 10(3): 2225, Jul. 2022. ilus, mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1399582

RESUMO

In this study, we surveyed the diversity and distribution of breeding birds in dominating habitat of Central High Atlas valleys and principal governing factors. In the point-counts method with 170 sampling points from 2018 to 2019, richness parameters and multivariate analysis were used to assess the distribution of recorded birds. We recorded 92 breeding birds of migrants (34%) and residents (68%), belonging to 34 families and 13 orders. The families of Muscicapidae (13 species), Fringillidae (8 species), and Accipitridae (7 species) were the most abundant, while the Regulidae, Malaconotidae, Acrocephalidae, Cettiidae, Pycnonotidae, Cinclidae, Oriolidae, Laniidae, Phylloscopidae, Troglodytidae, Meropidae, Coraciidae, Cuculidae, Caprimulgidae, Upupidae, and Ciconiidae, were the less observed with one bird species each. One species of conservation concern, namely the globally vulnerable Turtle dove, was recorded. On the other hand, Statistical analysis showed that bird richness was similar among forest stands, while abundance differed significantly. In contrast, both richness and abundance were statistically different among open habitats. Further, 46 species were found in Juniper stand surrounded by agricultural fields, followed by 30 species in Holm Oak stands where the density of trees, shrubs, and canopy coverage were higher, while in Black poplar stands characterised by higher trees and shrubs, and high availability of water hosted only 20 species. Rare and accidental birds dominate the forest and open lands, demonstrating the vulnerability of these habitats. This study could serve as a great reference for comparative studies of interesting birds on both slopes of the Mediterranean.


Assuntos
Aves/classificação , Distribuição Animal/classificação , Biodiversidade , Marrocos
8.
J Fish Biol ; 101(1): 236-248, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35591772

RESUMO

Coevolution with predators leads to the use of low-risk habitats by many prey species, which promotes survival during early developmental phases. These nurseries are valued by conservation and management agencies because of their contributions to adult populations. However, the physical and geographic characteristics, like shallow depths and isolation from other marine habitats, that restrict access to predators and thereby reduce risk to juvenile animals can also limit scientific research. Consequently, many nursery habitats are still unidentified and understudied. Here we used gillnet monitoring from 1982 to 2018 to delineate blacktip shark (Carcharhinus limbatus) nurseries in the north-western Gulf of Mexico and elucidated their physical, environmental and biological characteristics. Nursery habitats within estuaries (<2% of spatial area) were proximate to the Gulf of Mexico and exhibited significantly lower variability in salinity than non-nurseries. However, relative abundances of predators and prey were not significant delineators of nursery habitats. As such, food and risk may not influence juvenile blacktip habitat use as expected. Alternatively, reduced osmoregulatory stress attributed to predictable environments likely provides advantageous conditions for blacktips to develop foraging and antipredator tactics, which is vital prior to the winter migration of juvenile sharks into the Gulf of Mexico.


Assuntos
Tubarões , Animais , Ecossistema , Estuários , Golfo do México , Estações do Ano
9.
Biodivers Data J ; 10: e86756, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761537

RESUMO

The Pedra Branca Forest is in a highly urbanised region of the central portion of Rio de Janeiro City and comprises the largest urban forest in the world (> 12,000 ha). The local flora and fauna are protected by three conservation units and the Estação Biológica Fiocruz Mata Atlântica (EFMA), which comprises 462 hectares on the east side of the remnant. The local biodiversity is still little known compared to other Atlantic Forest remnants from the Rio de Janeiro State. Here, we provide results of a survey of medium- and large-sized terrestrial mammals from the EFMA. In addition, we analysed the distribution of this fauna along three habitat types defined as Peridomicile, Transitional Forest and Forest Core. Sampling was performed from 2017 to 2020 and comprised a camera-trap survey, interviews with residents and local workers and occasional records. Results include occurrence records for 16 autochthonous and one allochthonous (Callithrix sp.) wild mammals, which are distributed into 14 families and seven orders, in addition to the presence of free-ranging domestic dogs and cats. Four species are in some category of threat of extinction at national or global levels. Amongst them, Leontopithecusrosalia (first record for the Rio de Janeiro City in more than a century) and Leopardusguttulus are classified as Vulnerable by IUCN. Most wild native species were registered in the three habitat types, but with differences in the frequency of records. Our results indicate that the presence of domestic dogs and cats influenced the species composition in each area, with Nasuanasua, Dasyproctaleporina and Didelphisaurita less frequent in places where domestic dogs and cats are more frequent. This is the first systematic effort to understand the occurrence and distribution of mid- and large-sized mammals in the Pedra Branca Forest.

10.
Ecol Appl ; 32(1): e02482, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34674337

RESUMO

Apex predators drive top-down effects in ecosystems and the loss of such species can trigger mesopredator release. This ecological process has been well documented in human-modified small areas, but for management and conservation of ecological communities, it is important to know which human factors affect apex predator occurrence and which mediate mesopredators release at large scales. We hypothesized that mesopredators would avoid spatial and temporal overlap with the apex predator, the puma; but that human perturbations (i.e., cattle raising and trophy hunting) would dampen top-down effects and mediate habitat use. We installed 16 camera traps in each of 45, 10 × 10 km grid cells in the Caldén forest region of central Argentina resulting in 706 total stations covering 61,611 km2 . We used single-season occupancy and two-species co-occurrence models and calculated the species interaction factor (SIF) to explore the contributions of habitat, biotic, and anthropic variables in explaining co-occurrence between carnivore pairs. We also used kernel density estimation techniques to analyze temporal overlap in activity patterns of the carnivore guild. We found that puma habitat use increased with abundance of large prey and with proximity to protected areas. Geoffroy's cats and skunks spatially avoided pumas and this effect was strong and mediated by distance to protected areas and game reserves, but pumas did not influence pampas fox and pampas cat space use. At medium and low levels of puma occupancy, we found evidence of spatial avoidance between three pairs of mesocarnivores. All predators were mostly nocturnal and crepuscular across seasons and mesopredators showed little consistent evidence of changing activity patterns with varying levels of puma occupancy or human interference. We found potential for mesopredator release at large scale, especially on the spatial niche axis. Our results suggest that a combination of interacting factors, in conjunction with habitat features and intervening human activities, may make mesopredator release unlikely or difficult to discern at broad scales. Overall, we believe that promoting the creation of new protected areas linked by small forest patches would likely lead to increased predator and prey abundances, as well as the interactions among carnivores inside and outside of protected areas.


Assuntos
Efeitos Antropogênicos , Carnívoros , Florestas , Animais , Bovinos , Comportamento Predatório , Estações do Ano , Análise Espacial
11.
Integr Zool ; 17(2): 285-296, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33738919

RESUMO

Mammals can show conspicuous behavioral responses to thermal variation, including changes in movement patterns. We used an integrative approach to understand how environmental temperature can drive the movement behavior of a mammal with low capacity for physiological thermoregulation, the giant anteater (Myrmecophaga tridactyla). We tracked 52 giant anteaters in 7 areas throughout the Brazilian savannah. We estimated the distance moved, area used, use of forest areas, and mean environmental temperature for each monitoring day of each individual. We modeled these data with Mixed Structural Equations - considering the possible interactions between our variables and controlling for sex and body mass. Giant anteaters reduced displacement and increased forest use with decreasing environmental temperature, probably because of their low body heat production. It is possible that they reduce distance moved and area used by reducing the duration of activity. With decreasing temperature, forest habitats become warmer than open ones, besides buffer rain and chilly winds. Reducing displacement and using forests are important strategies to reduce body heat loss and the energetic costs of thermoregulation. However, decreasing movement can limit food access and, consequently, fitness. Therefore, we highlight the importance of forests as thermal shelters. With increasing frequency and intensity of extreme weather events, we showed the need to preserve forest patches to offer suitable conditions for tropical mammals' behavioral thermoregulation. In this context, policies favoring deforestation on Brazilian territory are especially worrisome. Finally, we emphasize the need of integrative approaches to understand the complex interactions between organisms and the environment.


Assuntos
Ecossistema , Vermilingua , Animais , Regulação da Temperatura Corporal , Florestas , Mamíferos , Temperatura
12.
Braz. j. biol ; 82: 1-7, 2022. map, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468572

RESUMO

Cranes are the large and attractive Creatures of nature with long necks, legs, and life-span. Adults of both sexes are the same with similar color patterns. Demoiselle cranes spend most of their lifespan on dry grasses. They are also found around the stream, rivers, shallow lakes, natural wetlands, and depressions. To evaluate the current status of habitat use and major threats a study was conducted in tehsil Domel district Bannu. Line transect method and water quality tests (temperature, PH, contamination of E-coli bacteria) were used. To determine the major threats questionnaire method was used. The whole data was analyzed by using SPSS 21 version. Based on the distribution four study sites were selected and four water samples from each study site were taken. Most sites were moderate to highly degraded except Kashoo and kurram river mixing point which was low degraded with livestock grazing and human activities. Water quality tests showed PH ranges from 7-9, temperature 6.5-8.5, and contamination of E-coli in all samples. The social survey revealed that hunting, habitat degradation, and pollution as major threats. Effective long-term conservation and management in the study area are needed to focus on the protection of disturbance-free habitat.


Guindastes são a grande e atraente criatura da natureza com um pescoço longo, pernas e vida útil. Adultos de ambos os sexos são os mesmos com padrões de cores semelhantes. Guindastes Demoiselle passam a maior parte da vida em gramíneas secas. Também se encontram ao redor do córrego, rios, lagos rasos, pântanos naturais e depressões. Para avaliar o estado atual do uso do hábitat e as principais ameaças, um estudo foi realizado no distrito de Tehsil Domel, em Bannu. Foram utilizados o método transect e testes de qualidade da água (temperatura, pH, contaminação da bactéria E. coli). Para determinar as principais ameaças foi utilizado o método de questionário. Todos os dados foram analisados por meio da versão SPSS 21. Com base na distribuição, foram selecionados quatro locais de estudo e quatro amostras de água de cada local de estudo. A maioria dos locais estava moderada a altamente degradada, exceto no ponto de encontro dos rios Kashoo e Kurram, que teve baixa degradação com pastagem de gado e atividades humanas. Os testes de qualidade da água mostraram variação de pH de 7-9, temperatura 6,5-8,5 e contaminação de E. coli em todas as amostras. A pesquisa do questionário revelou que a caça, a degradação do hábitat e a poluição são as principais ameaças. Efetiva conservação e gestão a longo prazo na área de estudo são necessárias para se concentrar na proteção de um hábitat livre de distúrbios.


Assuntos
Animais , Aves , Ecossistema , Escherichia coli , Meio Ambiente , Poluição Ambiental/análise , Poluição da Água , Água/análise
13.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468759

RESUMO

Abstract Cranes are the large and attractive Creatures of nature with long necks, legs, and life-span. Adults of both sexes are the same with similar color patterns. Demoiselle cranes spend most of their lifespan on dry grasses. They are also found around the stream, rivers, shallow lakes, natural wetlands, and depressions. To evaluate the current status of habitat use and major threats a study was conducted in tehsil Domel district Bannu. Line transect method and water quality tests (temperature, PH, contamination of E-coli bacteria) were used. To determine the major threats questionnaire method was used. The whole data was analyzed by using SPSS 21 version. Based on the distribution four study sites were selected and four water samples from each study site were taken. Most sites were moderate to highly degraded except Kashoo and kurram river mixing point which was low degraded with livestock grazing and human activities. Water quality tests showed PH ranges from 7-9, temperature 6.5-8.5, and contamination of E-coli in all samples. The social survey revealed that hunting, habitat degradation, and pollution as major threats. Effective long-term conservation and management in the study area are needed to focus on the protection of disturbance-free habitat.


Resumo Guindastes são a grande e atraente criatura da natureza com um pescoço longo, pernas e vida útil. Adultos de ambos os sexos são os mesmos com padrões de cores semelhantes. Guindastes Demoiselle passam a maior parte da vida em gramíneas secas. Também se encontram ao redor do córrego, rios, lagos rasos, pântanos naturais e depressões. Para avaliar o estado atual do uso do hábitat e as principais ameaças, um estudo foi realizado no distrito de Tehsil Domel, em Bannu. Foram utilizados o método transect e testes de qualidade da água (temperatura, pH, contaminação da bactéria E. coli). Para determinar as principais ameaçasfoi utilizado o método de questionário. Todos os dados foram analisados por meio da versão SPSS 21. Com base na distribuição, foram selecionados quatro locais de estudo e quatro amostras de água de cada local de estudo. A maioria dos locais estava moderada a altamente degradada, exceto no ponto de encontro dos rios Kashoo e Kurram, que teve baixa degradação com pastagem de gado e atividades humanas. Os testes de qualidade da água mostraram variação de pH de 7-9, temperatura 6,5-8,5 e contaminação de E. coli em todas as amostras. A pesquisa do questionário revelou que a caça, a degradação do hábitat e a poluição são as principais ameaças. Efetiva conservação e gestão a longo prazo na área de estudo são necessárias para se concentrar na proteção de um hábitat livre de distúrbios.

14.
Neotrop. ichthyol ; 20(1): e210101, 2022. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1365197

RESUMO

Color in animals responds to selective pressures and mediates the relationship between organism and environment. Reef fishes have the amplest variety of pigment cell types. This color patterns' variety may function as camouflage and be related to spatial use. We tested the hypothesis that the coloration of reef fish relates to water column stratum occupation. We predicted that sedentary animals connected to the background take advantage of background matching or disruptive patterns; more mobile demersal species apply disruptive coloration or motion-dazzle; and that pelagic species tend to have silvery bodies. We classified color patterns and categorized the water column stratum use for the Brazilian reef fishes in FishBase. Our analyses confirmed that irregular contrasting contour breaks, suggestive of disruptive coloration, occurs in benthic species and that silvering color was more prevalent in the pelagic stratum. Our raw data suggested a higher frequency of contrasting regular stripes, typical of motion-dazzle, in demersal species. However, the considerable uncertainty around estimates did not confirm this pattern. Reef fishes coloration is correlated to occupation of different strata in the water column. This can be interpreted as fishes being adapted to these habitats and partially explaining the richness of color patterns among them.(AU)


A cor nos animais responde a pressões seletivas e media a relação entre organismo e ambiente. Peixes recifais têm a maior variedade de tipos de células de pigmento. Essa variedade de padrões de coloração pode funcionar como camuflagem e estar relacionada ao uso espacial. Nós testamos a hipótese de que a coloração dos peixes recifais está relacionada à ocupação do estrato da coluna d'água. Previmos que animais sedentários conectados ao fundo aproveitam a semelhança ao fundo ou padrões disruptivos; espécies demersais mais móveis aplicam coloração disruptiva ou deslumbramento de movimento; e que espécies pelágicas tendem a apresentar corpos prateados. Classificamos os padrões de coloração e categorizamos o uso do estrato da coluna d'água para os peixes recifais brasileiros no FishBase. Nossas análises confirmaram que quebras de contorno irregulares, sugerindo coloração disruptiva, ocorrem em espécies bentônicas e que a cor prateada prevaleceu no estrato pelágico. Nossos dados brutos sugeriram uma maior frequência de listras contrastantes, típicas do deslumbramento de movimento, em espécies demersais. Mas a considerável incerteza dessas estimativas não confirmou esse padrão. A coloração dos peixes recifais está correlacionada com a ocupação de diferentes estratos da coluna d'água. Isso pode ser interpretado como peixes sendo adaptados a estes habitats, explicando em parte a riqueza de padrões de coloração entre eles.(AU)


Assuntos
Animais , Ecossistema , Cadeia Alimentar , Meio Ambiente , Peixes
15.
Braz. J. Biol. ; 82: 1-7, 2022. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-32958

RESUMO

Cranes are the large and attractive Creatures of nature with long necks, legs, and life-span. Adults of both sexes are the same with similar color patterns. Demoiselle cranes spend most of their lifespan on dry grasses. They are also found around the stream, rivers, shallow lakes, natural wetlands, and depressions. To evaluate the current status of habitat use and major threats a study was conducted in tehsil Domel district Bannu. Line transect method and water quality tests (temperature, PH, contamination of E-coli bacteria) were used. To determine the major threats questionnaire method was used. The whole data was analyzed by using SPSS 21 version. Based on the distribution four study sites were selected and four water samples from each study site were taken. Most sites were moderate to highly degraded except Kashoo and kurram river mixing point which was low degraded with livestock grazing and human activities. Water quality tests showed PH ranges from 7-9, temperature 6.5-8.5, and contamination of E-coli in all samples. The social survey revealed that hunting, habitat degradation, and pollution as major threats. Effective long-term conservation and management in the study area are needed to focus on the protection of disturbance-free habitat. (AU)


Guindastes são a grande e atraente criatura da natureza com um pescoço longo, pernas e vida útil. Adultos de ambos os sexos são os mesmos com padrões de cores semelhantes. Guindastes Demoiselle passam a maior parte da vida em gramíneas secas. Também se encontram ao redor do córrego, rios, lagos rasos, pântanos naturais e depressões. Para avaliar o estado atual do uso do hábitat e as principais ameaças, um estudo foi realizado no distrito de Tehsil Domel, em Bannu. Foram utilizados o método transect e testes de qualidade da água (temperatura, pH, contaminação da bactéria E. coli). Para determinar as principais ameaças foi utilizado o método de questionário. Todos os dados foram analisados por meio da versão SPSS 21. Com base na distribuição, foram selecionados quatro locais de estudo e quatro amostras de água de cada local de estudo. A maioria dos locais estava moderada a altamente degradada, exceto no ponto de encontro dos rios Kashoo e Kurram, que teve baixa degradação com pastagem de gado e atividades humanas. Os testes de qualidade da água mostraram variação de pH de 7-9, temperatura 6,5-8,5 e contaminação de E. coli em todas as amostras. A pesquisa do questionário revelou que a caça, a degradação do hábitat e a poluição são as principais ameaças. Efetiva conservação e gestão a longo prazo na área de estudo são necessárias para se concentrar na proteção de um hábitat livre de distúrbios.(AU)


Assuntos
Animais , Aves , Ecossistema , Água/análise , Escherichia coli , Meio Ambiente , Poluição Ambiental/análise , Poluição da Água
16.
Acta amaz ; 52(3): 236-240, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1392848

RESUMO

The relationship between Odonata and vegetation in Amazonia has been studied primarily in streams. In this study, I examined the abundance of adult Odonata in two vegetation types (shrubs and herbs) surrounding an oxbow lake in the Peruvian Amazon. Daytime visual samplings of Odonata were carried out in time blocks along transects in each habitat. Thirteen taxa were identified. Five species were similarly abundant in both habitats, three used mainly herbs, and one mainly shrubs, with no variation among time blocks. The results suggest that most Anisoptera and Zygoptera are adapted to unshaded areas of the lake. Some Odonata also were observed during sunless days with light rainfall, suggesting they are adapted to rainy conditions in tropical climate.(AU)


La relación entre Odonata y vegetación en la Amazonía ha sido estudiada principalmente en arroyos. En este estudio, se examinó la abundancia de adultos de Odonata en dos tipos de vegetación (arbustos y hierbas) alrededor de un lago de herradura en la Amazonía peruana. Muestreos visuales diurnos fueron realizados en bloques temporales a lo largo de cada hábitat. Trece taxones fueron identificados. Cinco especies fueron similarmente abundantes en los dos tipos de hábitat, tres usaron principalmente hierbas y una principalmente arbustos, esto no varió entre los bloques temporales. Los resultados sugieren que la mayoría de Anisoptera y Zygoptera están adaptados a áreas sin sombra del lago. Algunas libélulas fueron observadas durante días sin sol y con llovizna, sugiriendo que se encuentran adaptadas a condiciones de lluvia en climas tropicales.(AU)


Assuntos
Animais , Especificidade da Espécie , Odonatos/classificação , Distribuição Animal/fisiologia , Peru , Ecossistema Amazônico
17.
Pap. avulsos zool ; 62: e202262039, 2022. mapas, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1396450

RESUMO

Natural resources are depleted in fragmented landscapes that have their vegetation also altered. As a result, the microhabitat diversity and the composition and distribution of local species are affected. In this study, we evaluated the small mammals' community diversity, composition and microhabitat selection in two Atlantic Forest fragments, in an ecotone area with the Pampa biome, southern Brazil. We recorded five rodents (Akodon montensis, Oligoryzomys nigripes, Sooretamys angouya, Juliomys pictipes and the exotic Rattus rattus) and one marsupial (Didelphis albiventris). Both fragments were dominated by the generalist rodent A. montensis. Akodon montensis and O. nigripes showed similar habitat preferences: ground covered by rocks and higher values of vegetation obstruction. Sooretamys angouya preferred places with higher abundance of trees. Fruit availability was important for A. montensis and D. albiventris, highlighting the importance of this food resource for local wildlife, and the potential role of these species as seed predators and dispersers. Small species richness, the presence of an exotic species and high dominance level suggest that the study area is highly degraded.(AU)


Assuntos
Animais , Roedores/fisiologia , Comportamento Alimentar/fisiologia , Marsupiais/fisiologia , Ecossistema , Pradaria
18.
Braz. j. biol ; 82: e242636, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285595

RESUMO

Cranes are the large and attractive Creatures of nature with long necks, legs, and life-span. Adults of both sexes are the same with similar color patterns. Demoiselle cranes spend most of their lifespan on dry grasses. They are also found around the stream, rivers, shallow lakes, natural wetlands, and depressions. To evaluate the current status of habitat use and major threats a study was conducted in tehsil Domel district Bannu. Line transect method and water quality tests (temperature, PH, contamination of E-coli bacteria) were used. To determine the major threats questionnaire method was used. The whole data was analyzed by using SPSS 21 version. Based on the distribution four study sites were selected and four water samples from each study site were taken. Most sites were moderate to highly degraded except Kashoo and kurram river mixing point which was low degraded with livestock grazing and human activities. Water quality tests showed PH ranges from 7-9, temperature 6.5-8.5, and contamination of E-coli in all samples. The social survey revealed that hunting, habitat degradation, and pollution as major threats. Effective long-term conservation and management in the study area are needed to focus on the protection of disturbance-free habitat.


Guindastes são a grande e atraente criatura da natureza com um pescoço longo, pernas e vida útil. Adultos de ambos os sexos são os mesmos com padrões de cores semelhantes. Guindastes Demoiselle passam a maior parte da vida em gramíneas secas. Também se encontram ao redor do córrego, rios, lagos rasos, pântanos naturais e depressões. Para avaliar o estado atual do uso do hábitat e as principais ameaças, um estudo foi realizado no distrito de Tehsil Domel, em Bannu. Foram utilizados o método transect e testes de qualidade da água (temperatura, pH, contaminação da bactéria E. coli). Para determinar as principais ameaçasfoi utilizado o método de questionário. Todos os dados foram analisados por meio da versão SPSS 21. Com base na distribuição, foram selecionados quatro locais de estudo e quatro amostras de água de cada local de estudo. A maioria dos locais estava moderada a altamente degradada, exceto no ponto de encontro dos rios Kashoo e Kurram, que teve baixa degradação com pastagem de gado e atividades humanas. Os testes de qualidade da água mostraram variação de pH de 7-9, temperatura 6,5-8,5 e contaminação de E. coli em todas as amostras. A pesquisa do questionário revelou que a caça, a degradação do hábitat e a poluição são as principais ameaças. Efetiva conservação e gestão a longo prazo na área de estudo são necessárias para se concentrar na proteção de um hábitat livre de distúrbios.


Assuntos
Humanos , Animais , Masculino , Feminino , Aves , Ecossistema , Paquistão , Rios , Áreas Alagadas
19.
Am J Primatol ; 83(5): e23243, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33755228

RESUMO

Habitats with spatial variation in food availability, predation risk, and hunting pressure allow us to study how animals resolve the trade-off between food searching and predator avoidance. We investigated the influence of food availability, predation risk, and the perceived predation risk on habitat use by a primate living under high hunting pressure, the yellow-breasted capuchin monkeys, Sapajus xanthosternos, at Una Biological Reserve (ReBio Una). We hypothesized that the hunting pressure occurring in the capuchins' home range would favor predator avoidance to the detriment of searching for food. We characterized a set of covariates related to resource availability (fruit and invertebrate biomasses, feeding on dispersed and clumped food items, sleeping sites), perceived predation risk (alarm calls given to terrestrial and aerial predators, silent group movement, and vigilance behavior), and actual predation risk (evidence of hunting) and estimated their effects on how one group of capuchin monkeys uses its habitat. The group divides its time among three major forest types within their home range: agroforest, mature, and secondary. Our results suggest that the actual and perceived risk of hunting by humans, as well as the perceived predation risk by both terrestrial and aerial predators, were significant determinants of capuchin monkeys' space use. Yellow-breasted capuchin monkeys' space use was negatively related to the risk of hunting by humans (actual evidence and silent behavior), the perceived risk of predation by both aerial and terrestrial predators, and the presence of sleeping sites. Capuchin monkeys' use of space was not related to the biomass of fruits in the habitat, and the biomass of invertebrates had a very low positive effect. We confirmed our prediction that in a habitat with high hunting pressure, the risk of predation, both perceived and actual, had a more significant impact on how yellow-breasted capuchins used space than did food availability.


Assuntos
Sapajus , Animais , Brasil , Cebus , Ecossistema , Medo , Florestas , Comportamento Predatório
20.
Braz. J. Biol. ; 81(1): 164-177, Jan.-Feb. 2021. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-30136

RESUMO

Estuaries are used by waterbirds as foraging, resting and nesting sites, serving also as shelter for migratory birds. The dynamics of this avifauna in an aquatic environment may be associated with the differences of time of day, tide height, temperature, wind speed and use of the site by different species. This study had the objective of evaluating behavioral aspects of aquatic birds, relating the influence of environmental variables with their activities. Bird counts were performed at the mouth of two important rivers of the state of Santa Catarina, Brazil, during two-hour intervals throughout the day in monthly samplings between June (2015) and May (2016). A total of 44 species were recorded, ten of which were migratory. The most recorded behaviors were foraging and resting. The Kruskal-Wallis analysis indicated no significant difference in behavior between the sampling intervals. The Bray-Curtis similarity test resulted in three groups: 1) - species that foraged most of the time; 2) - species that rested most of the time; and 3) - same time in both activities. The Indicator Species Analysis showed that 17 species were associated with only one microhabitat and 15 species with more than one. The Canonical Correlation Analysis indicated that only tide height, temperature and rainfall variables were correlated with the behaviors performed and only the resting activity was positively correlated with all variables. This may be associated with thermoregulation and the ability of some species to stay in midlitoral at high tide. The results demonstrate that different waterbird species used the studied areas in different ways. Thus, the heterogeneity of microhabitats in an aquatic environment of extreme importance for the coexistence and maintenance of the diversity of waterbirds.(AU)


Estuários são utilizados por aves aquáticas como locais de forrageio, descanso e nidificação, servindo, também, como pontos de parada para aves migratórias. A dinâmica dessa avifauna em um ambiente pode estar associada a diferenças entre horários do dia, altura da maré, temperatura, velocidade do vento e uso do local. Esse trabalho teve o objetivo de avaliar aspectos comportamentais de aves aquáticas, relacionando a influência de variáveis ambientais com suas atividades. Amostragens mensais foram realizadas na foz de dois importantes rios do Estado de Santa Catarina, Brasil, entre junho de 2015 e maio de 2016, em intervalos de duas horas no decorrer do dia. Um total de 44 espécies foram registradas, dez das quais foram migratórias. Os comportamentos mais observados foram forrageio e descanso. A análise de Kruskall-Wallis não indicou diferenças significativas no comportamento entre os horários de amostragem. O teste de similaridade Bray-Curtis resultou em três agrupamentos: 1) - espécies que forragearam na maior parte do tempo; 2) - espécies que descansaram na maior parte do tempo; e 3) - mesma quantidade de tempo em ambas atividades. A Análise de Espécies Indicadoras mostrou que 17 espécies estiveram associadas com apenas um microhabitat e 15 espécies com mais de um. A Análise de Correlação Canônica indicou que apenas as variáveis maré, temperatura e precipitação foram significativamente correlacionadas com os comportamentos demonstrados e apenas a atividade de descanso foi positivamente correlacionada com as todas as variáveis. Isso pode estar associado com a termorregulação e com a habilidade de algumas espécies de permanecer no mediolitoral durante a maré cheia. Os resultados demonstram que diferentes espécies de aves aquáticas utilizaram as áreas estudadas de diferentes maneiras. Assim, a heterogeneidade de microhabitats em um ambiente aquático é de extrema importância para a coexistência e a manutenção da diversidade de aves.(AU)


Assuntos
Animais , Aves , Fauna Aquática , Comportamento Animal , Estuários
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