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1.
Braz. j. biol ; 83: e247374, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285623

RESUMO

Abstract The present study was conducted to evaluate the diversity, distribution (C) and relative abundance (RA) of the mosquito fauna (Diptera: Culicidae) of Malakand and Dir Lower, Pakistan. Collection of specimens (n = 1087) was made during September 2018 to July 2019 at six different habitats including freshwater bodies, rice fields, animal sheds, indoors, drains and sewage waters. Specimens were collected through light traps, pyrethrum spray, aspirators and nets and subsequently killed, preserved and then arranged in entomological boxes for identification. Three genera were identified namely Culex, Anopheles and Aedes. A total of fourteen species were identified namely: Cx. quinquefasciatus (Say, 1823), An. stephensi (Liston, 1901), Cx. tritaeniorhynchus (Giles, 1901), Ae. vittatus (Bigot, 1861), An. maculatus (Theobald, 1901), An. fluviatilis (James, 1902), Cx. vishnui (Theobald, 1901), Ae. aegypti (Linnaeus, 1762) An. subpictus (Grassi, 1899), An. dthali (Patton, 1905), An. culicifascies (Giles, 1901), An. pallidus (Theobald, 1901), Ae. albopictus (Skuse, 1894) and An. annularis (van der Wulp, 1884). Cx. quinquefasciatus was found constantly distributed in the study area with RA = 16.5% and C = 100%. An. annularis was found as a satellite species, sporadically distributed in the study area having RA = 0.9% and C = 17%. Diversity indices of mosquitoes in the studied habitats were found as, Shannon-Wiener Index (2.415), Simpson Index (9.919), Fisher's Index (2.269) and Margalef's Index (1.859). A statistically significant difference was recorded in mosquito diversity in the six habitats (Kruskal-Wallis, chi-squared, H = 17.5, df = 5, P = 0.003 at α = 0.05). The present study encompasses mosquito fauna of Malakand, Pakistan with respect to diversity, relative abundance and distribution in diverse habitats and all seasons of the year. This will assist scientists working in various fields related with epidemiology, medical and veterinary entomology, ecology and allied areas of biological sciences.


Resumo O presente estudo foi conduzido para avaliar a diversidade, distribuição (C) e abundância relativa (RA) da fauna de mosquitos (Diptera: Culicidae) de Malakand e Dir Lower, Paquistão. A coleta de espécimes (n = 1087) foi feita durante o período de setembro de 2018 a julho de 2019 em seis habitats diferentes, incluindo corpos d'água, campos de arroz, galpões de animais, ambientes internos, ralos e águas residuais. Os espécimes foram coletados por meio de armadilhas luminosas, spray de piretro, aspiradores e redes e posteriormente mortos, preservados e depois dispostos em caixas entomológicas para identificação. Três gêneros foram identificados, nomeadamente Culex, Anopheles e Aedes. Um total de 14 espécies foi identificado, a saber: Cx. quinquefasciatus (Say, 1823), An. stephensi (Liston, 1901), Cx. tritaeniorhynchus (Giles, 1901), Ae. vittatus (Bigot, 1861), An. maculatus (Theobald, 1901), An. fluviatilis (James, 1902), Cx. vishnui (Theobald, 1901), Ae. aegypti (Linnaeus, 1762), An. subpictus (Grassi, 1899), An. dthali (Patton, 1905), An. culicifascies (Giles, 1901), An. pallidus (Theobald, 1901), Ae. albopictus (Skuse, 1894) e An. annularis (Van der Wulp, 1884). Cx. quinquefasciatus foi encontrado constantemente distribuído na área de estudo com AR = 16,5% e C = 100%. A. annularis foi encontrada como espécie satélite, distribuída esporadicamente na área de estudo com RA = 0,9% e C = 17%. Os índices de diversidade de mosquitos nos habitats estudados foram encontrados como índice de Shannon-Wiener (2,415), índice de Simpson (9,919), índice de Fisher (2,269) e índice de Margalef (1,859). Uma diferença estatisticamente significativa foi registrada na diversidade de mosquitos nos seis habitats (Kruskal-Wallis, qui-quadrado, H = 17,5, df = 5, P = 0,003 em α = 0,05). O presente estudo abrange a fauna de mosquitos de Malakand, Paquistão, com respeito à diversidade, abundância relativa e distribuição em diversos habitats e em todas as estações do ano. Isso ajudará os cientistas que trabalham em vários campos relacionados com a epidemiologia, entomologia médica e veterinária, ecologia e áreas afins das ciências biológicas.


Assuntos
Animais , Culicidae , Paquistão , Estações do Ano , Ecossistema , Ecologia
2.
J Anim Ecol ; 91(8): 1558-1561, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35922967

RESUMO

Research Highlight: McIntosh, A. R., Greig, H. S., & Howard, S. (2022). Regulation of open populations of a stream insect through larval density dependence. Journal of Animal Ecology. https://doi.org/10.1111/1365-2656.13696. Despite decades of research on population regulation through density dependence, it remains challenging to identify and understand the relative importance of mechanisms governing open populations of organisms with complex life cycles. McIntosh et al. (2022) manipulated density of aquatic invertebrates in the field, and then followed populations for 2 years to track the effects on abundance through multiple life-history stages. The authors found that their density manipulation, performed on larvae that were about to pupate, had minimal effects on the number of emergent adults collected several months later. The manipulation had a similarly negligible influence on the number of egg masses laid at study locations. The authors attribute this to stochasticity around dispersal of flying adults through the terrestrial environment. However, later in the study, the authors found evidence of density-dependent population regulation among larval stages, seemingly controlled by resource availability. These results suggest that population dynamics depend on multiple mechanisms operating at different points in organisms' life history, which could either help or hinder population persistence with disturbance or environmental change.


Assuntos
Ecologia , Estágios do Ciclo de Vida , Animais , Larva , Estágios do Ciclo de Vida/fisiologia , Densidade Demográfica , Dinâmica Populacional , Rios
3.
PLoS One ; 17(8): e0272359, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35925949

RESUMO

Understanding the links between species and their environment is critical for species management. This is particularly true for organisms of medical and/or economic significance. The 'Irukandji' jellyfish (Carukia barnesi) is well known for its small size, cryptic nature, and highly venomous sting. Being the namesake of the Irukandji syndrome, contact with this marine stinger often leads to hospitalization and can be fatal. Consequently, the annual occurrence of this organism is believed to cost the Australian government an estimated $AUD3 billion annually in medical costs and losses for tourism. Despite its economic importance the logistical difficulties related to surveying C.barnesi in situ has led to a paucity of knowledge regarding its ecology and significantly impeded management strategies to date. In this study, we use six years of direct C. barnesi capture data to explore patterns pertaining to the annual occurrence and abundance of this species in the nearshore waters of the Cairns coast. We provide novel insights into trends in medusae aggregations and size distribution and primarily focus on the potential role of environmental drivers for annual C. barnesi occurrence patterns. Using a two-part hurdle model, eight environmental parameters were investigated over four time periods for associations with records of medusa presence and abundance. Final models showed a small amount of variation in medusa presence and abundance patterns could be accounted for by long-term trends pertaining to rainfall and wind direction. However, the assessed environmental parameters could not explain high annual variation or site location effects. Ultimately best-fit models had very low statistical inference power explaining between 16 and 20% of the variance in the data, leaving approximately 80% of all variation in medusa presence and abundance unexplained.


Assuntos
Lesões Acidentais , Mordeduras e Picadas , Venenos de Cnidários , Cubomedusas , Hidrozoários , Cifozoários , Animais , Austrália , Mordeduras e Picadas/epidemiologia , Ecologia
4.
Comput Intell Neurosci ; 2022: 5465488, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785065

RESUMO

The study of human settlement environment, especially the complete study of human settlement environment in mountainous region, is a huge systematic project, which involves almost all aspects of human knowledge system at the semantic level. It is an important task to establish a systematic cognitive model of human settlement environment and carry out practical verification. In recent years, due to the rise of tourism real estate, mountain tourism real estate, as a type of tourism real estate, has attracted people's attention, and its hidden economic, social, and ecological benefits make it develop rapidly. The purpose of this study is to improve the theoretical system of tourism real estate landscape planning and mountain landscape resource protection system with 3D image technology, which has important theoretical and practical significance for exploring the sustainable development method of mountain tourism real estate landscape. This study locates the research type of mountain tourism real estate, and it is the first time to study mountain tourism, explores the specific planning of mountain tourism real estate development measures, and preliminary establish the theoretical system of mountain tourism real estate development. It brings a new idea for the development of mountain tourism real estate and puts forward the direction and method of planning.


Assuntos
Ecologia , Turismo , Humanos , Tecnologia , Água
5.
Adv Mar Biol ; 91: 1-286, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35777924

RESUMO

Holothuria scabra is one of the most intensively studied holothuroids, or sea cucumbers (Echinodermata: Holothuroidea), having been discussed in the literature since the early 19th century. The species is important for several reasons: (1) it is widely distributed and historically abundant in several shallow soft-bottom habitats throughout the Indo-Pacific, (2) it has a high commercial value on the Asian markets, where it is mainly sold as a dried product (beche-de-mer) and (3) it is the only tropical holothuroid species that can currently be mass-produced in hatcheries. Over 20 years have elapsed since the last comprehensive review on H. scabra published in 2001. Research on H. scabra has continued to accumulate, fuelled by intense commercial exploitation, and further declines in wild stocks over the entire distribution range. This review compiles data from over 950 publications pertaining to the biology, ecology, physiology, biochemical composition, aquaculture, fishery, processing and trade of H. scabra, presenting the most complete synthesis to date, including scientific papers and material published by local institutions and/or in foreign languages. The main goal of this project was to summarize and critically discuss the abundant literature on this species, making it more readily accessible to all stakeholders aiming to conduct fundamental and applied research on H. scabra, or wishing to develop aquaculture, stock enhancement and management programs across its geographic range.


Assuntos
Holothuria , Pepinos-do-Mar , Animais , Equinodermos , Ecologia , Pesqueiros
6.
Sci Rep ; 12(1): 12775, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896571

RESUMO

The domestic cat is the world's most popular pet and one of the most detrimental predators in terrestrial ecosystems. Effective protection of wildlife biodiversity demands detailed tracking of cat trophic ecology, and stable isotopes serve as a powerful proxy in dietary studies. However, a variable diet can make an isotopic pattern unreadable in opportunistic predators. To evaluate the usefulness of the isotopic method in cat ecology, we measured C and N isotope ratios in hundreds of archaeological cat bones. We determined trends in cat trophic paleoecology in northern Europe by exploiting population-scale patterns in animals from diverse locations. Our dataset shows a high variability of isotopic signals related to the socio-economic and/or geomorphological context. This points toward regularities in isotopic patterns across past cat populations. We provide a generalized guide to interpret the isotopic ecology of cats, emphasizing that regional isotopic baselines have a major impact on the isotopic signal.


Assuntos
Ecossistema , Isótopos , Animais , Isótopos de Carbono/análise , Gatos , Dieta , Ecologia , Europa (Continente) , Isótopos de Nitrogênio/análise
7.
Nat Commun ; 13(1): 4340, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896591

RESUMO

Body size and shape play fundamental roles in organismal function and it is expected that animals may possess body proportions that are well-suited to their ecological niche. Tetrapods exhibit a diverse array of body shapes, but to date this diversity in body proportions and its relationship to ecology have not been systematically quantified. Using whole-body skeletal models of 410 extinct and extant tetrapods, we show that allometric relationships vary across individual body segments thereby yielding changes in overall body shape as size increases. However, we also find statistical support for quadratic relationships indicative of differential scaling in small-medium versus large animals. Comparisons of locomotor and dietary groups highlight key differences in body proportions that may mechanistically underlie occupation of major ecological niches. Our results emphasise the pivotal role of body proportions in the broad-scale ecological diversity of tetrapods.


Assuntos
Evolução Biológica , Ecologia , Animais , Tamanho Corporal
8.
Sci Rep ; 12(1): 12813, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896765

RESUMO

Freshwaters are under accelerated human pressure, and mollusk communities are among its most sensitive, threatened, and valuable components. To the best of our knowledge, the overall effects of damming, environment, space, time, and invasive alien mollusk species, on structural and functional responses of native mollusk communities were not yet compared. Using historical information and recent data from a river, we aimed to investigate and disentangle these effects and evaluate the differences in structural and functional responses of natives and alien invasives to the same predictors. Variation partitioning showed that alien species were as important predictors as were environmental factors and time in explaining species composition of native freshwater mollusk communities. Aliens were more independent of environmental conditions than natives and responded to different drivers, partially explaining their invasion success. The increased abundance of some alien gastropods was positively related to taxonomic diversity, while certain alien bivalves were negatively associated with the functional diversity of native communities. We introduce a cumulative variation partitioning with multiple response (native and alien) and predictor matrices, along with a diagram to show their relations, advocating for a conceptual shift in future community ecology, from "variables to matrices" and from "multivariate analyses to multi-matrix statistical modeling".


Assuntos
Espécies Introduzidas , Plantas , Ecologia , Ecossistema , Humanos
9.
Ecol Lett ; 25(8): 1760-1782, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35791088

RESUMO

Pathogen transmission depends on host density, mobility and contact. These components emerge from host and pathogen movements that themselves arise through interactions with the surrounding environment. The environment, the emergent host and pathogen movements, and the subsequent patterns of density, mobility and contact form an 'epidemiological landscape' connecting the environment to specific locations where transmissions occur. Conventionally, the epidemiological landscape has been described in terms of the geographical coordinates where hosts or pathogens are located. We advocate for an alternative approach that relates those locations to attributes of the local environment. Environmental descriptions can strengthen epidemiological forecasts by allowing for predictions even when local geographical data are not available. Environmental predictions are more accessible than ever thanks to new tools from movement ecology, and we introduce a 'movement-pathogen pace of life' heuristic to help identify aspects of movement that have the most influence on spatial epidemiology. By linking pathogen transmission directly to the environment, the epidemiological landscape offers an efficient path for using environmental information to inform models describing when and where transmission will occur.


Assuntos
Transmissão de Doença Infecciosa , Ecologia , Epidemiologia , Movimento , Geografia
10.
Proc Biol Sci ; 289(1978): 20220862, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35858070

RESUMO

Understanding the sensory ecology of species is vital if we are to predict how they will function in a changing environment. Visual cues are fundamentally important for many predators when detecting and capturing prey. However, many marine areas have become more turbid through processes influenced by climate change, potentially affecting the ability of marine predators to detect prey. We performed the first study that directly relates a pelagic seabird species's foraging behaviour to oceanic turbidity. We collected biologging data from 79 foraging trips and 5472 dives of a visually dependent, pursuit-diving seabird, the Manx shearwater (Puffinus puffinus). Foraging behaviour was modelled against environmental variables affecting underwater visibility, including water turbidity, cloud cover and solar angle. Shearwaters were more likely to initiate area-restricted search and foraging dives in clearer waters. Underwater visibility also strongly predicted dive rate and depth, suggesting that fine-scale prey capture was constrained by the detectability of prey underwater. Our novel use of dynamic descriptors of underwater visibility suggests that visual cues are vital for underwater foraging. Our data indicate that climate change could negatively impact seabird populations by making prey more difficult to detect, compounded by the widely reported effects of reduced prey populations.


Assuntos
Mergulho , Animais , Aves , Ecologia , Comportamento Alimentar , Comportamento Predatório
11.
Artigo em Inglês | MEDLINE | ID: mdl-35886243

RESUMO

The quantitative analysis of the urban-rural integration development (URID) level and its driving factors is of great significance for the new-type urbanization of urban agglomerations. This study constructed a multidimensional framework in the perspective of a population-space-economy-society-ecology framework to measure the URID level from 2000 to 2020 and further explored the driving mechanism of the URID changes by a geographical detector model in the Hangzhou Bay urban agglomeration (HBUA). The results showed that the land-use change in the HBUA from 2000 to 2020 showed a typical characteristic of the transition between cultivated and construction land. The URID level in the HBUA improved from 0.294 in 2000 to 0.563 in 2020, and the year 2005 may have been the inflection point of URID in the HBUA. The URID level showed a significant spatial aggregation with high values. Hangzhou, Jiaxing, and Ningbo were hot spots since 2015, and the cold spots were Huzhou and Shaoxing. The population and spatial integration had more important impacts on URID levels in 2000, 2005, and 2020, while economic and social integration had more significant impacts on URID levels in 2010 and 2015. This study provided a deeper understanding of the evolution of URID in an urban agglomeration and could be used as a reference for decision makers.


Assuntos
Baías , Urbanização , China , Cidades , Ecologia , Geografia , Rios , Reforma Urbana
12.
Sci Rep ; 12(1): 11695, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803997

RESUMO

Cryptic species that coexist in sympatry are likely to simultaneously experience strong competition and hybridization. The first phenomenon would lead to character displacement, whereas the second can potentially promote morphological similarity through adaptive introgression. The main goal of this work was to investigate the effect of introgressive hybridization on the morphology of cryptic Iberian Eptesicus bats when facing counteracting evolutionary forces from interspecific competition. We found substantial overlap both in dentition and in wing morphology traits, though mainly in individuals in sympatry. The presence of hybrids contributes to a fifth of this overlap, with hybrids showing traits with intermediate morphometry. Thus, introgressive hybridization may contribute to species adaptation to trophic and ecological space responding directly to the macro-habitats characteristics of the sympatric zone and to local prey availability. On the other hand, fur shade tended to be browner and brighter in hybrids than parental species. Colour differences could result from partitioning of resources as an adaptation to environmental factors such as roost and microhabitats. We argue that a balance between adaptive introgression and niche partitioning shapes species interactions with the environment through affecting morphological traits under selection.


Assuntos
Adaptação Biológica/fisiologia , Quirópteros/anatomia & histologia , Hibridização Genética/fisiologia , Animais , Evolução Biológica , Quirópteros/genética , Dentição , Ecologia , Introgressão Genética , Humanos , Simpatria , Asas de Animais/anatomia & histologia
13.
PLoS One ; 17(7): e0271076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35802585

RESUMO

Due to the fragmentation of protected areas (PA), it is important to build ecological corridors in order to connect scattered PA and form protection networks for biodiversity conservation. We take the Chinese ecological conservation redline (ECR) as an example to study the construction of ecological corridors. China has defined ECR to improve the system of PA in key ecological functional zones, nature reserves, and areas of sensitive and fragile ecological environment. In this study, 187 core areas of ECR were identified using ArcGIS masking and dissolving technology to build corridors, covering 95% of the total ECR areas. Using the Linkage Mapper tool and the Pinchpoint Mapper, we identified 454 ecological corridors 68,794 km long. The results of the line density analysis showed that there are 9 key regional biological corridors connected to the ECR at the national scale, which must focus on protecting and strengthening ecological construction during the implementation of ecological conservation redline policy. Our study will provide references for developing a regional pattern of ecological security, territorial spatial planning, and will promote the implementation of biodiversity conservation policies.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Biodiversidade , China , Ecossistema
14.
Comput Intell Neurosci ; 2022: 9945687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875779

RESUMO

The interbasin water transfer project has realized the optimal allocation of water resources, improved economic benefits, improved people's life and welfare, and had an impact on the ecology. Taking Anhui Jianghuai water transfer project as an example, this study uses morphological spatial pattern analysis (MSPA) to identify the core area, selects the patches in the core area, identifies the source according to the patch importance index, constructs the basic resistance surface according to the resistance factor, modifies the basic resistance surface by using the landscape connectivity index, and constructs the ecological corridor by combining the minimum cumulative resistance (MCR) model and the loop model (curve) to build the ecological network of the completed Huaihe River Water Transfer Project (Anhui). The results show that there are 83 sources, 197 potential ecological corridors, and 80 ecological nodes in the ecological network of Anhui Jianghuai project. Ecological network optimization strategies and protection suggestions are put forward for ecological sources, ecological corridors, and ecological nodes, respectively, so as to provide scientific reference and basis for the ecological environment protection and high-quality development of Anhui Jianghuai water transfer project.


Assuntos
Conservação dos Recursos Naturais , Ecologia , China , Conservação dos Recursos Naturais/métodos , Humanos , Rios , Água , Recursos Hídricos
15.
PLoS Negl Trop Dis ; 16(7): e0010059, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35793379

RESUMO

BACKGROUND: Dengue's emergence in West Africa was typified by the Burkina Faso outbreaks in 2016 and 2017, the nation's largest to date. In both years, we undertook three-month surveys of Aedes populations in or near the capital city Ouagadougou, where the outbreaks were centered. METHODOLOGY: In 1200LG (urban), Tabtenga (peri-urban) and Goundry (rural) localities, we collected indoor and outdoor resting mosquito adults, characterized larval habitats and containers producing pupae and reared immature stages to adulthood in the laboratory for identification. All mosquito adults were identified morphologically. Host species (from which bloodmeals were taken) were identified by PCR. Generalized mixed models were used to investigate relationships between adult or larval densities and multiple explanatory variables. RESULTS: From samples in 1,780 houses, adult Ae. aegypti were significantly more abundant in the two urban localities (Tabtenga and 1200 LG) in both years than in the rural site (Goundry), where Anopheles spp. were far more common. Results from adult collections indicated a highly exophilic and anthropophilic (>90% bloodmeals of human origin) vector population, but with a relatively high proportion of bloodfed females caught inside houses. Habitats producing most pupae were waste tires (37% of total pupae), animal troughs (44%) and large water barrels (30%). While Stegomyia indices were not reliable indicators of adult mosquito abundance, shared influences on adult and immature stage densities included rainfall and container water level, collection month and container type/purpose. Spatial analysis showed autocorrelation of densities, with a partial overlap in adult and immature stage hotspots. CONCLUSION: Results provide an evidence base for the selection of appropriate vector control methods to minimize the risk, frequency and magnitude of future outbreaks in Ouagadougou. An integrated strategy combining community-driven practices, waste disposal and insecticide-based interventions is proposed. The prospects for developing a regional approach to arbovirus control in West Africa or across Africa are discussed.


Assuntos
Aedes , Arbovírus , Dengue , Adulto , Animais , Burkina Faso/epidemiologia , Dengue/epidemiologia , Surtos de Doenças , Ecologia , Feminino , Humanos , Larva , Mosquitos Vetores , Pupa , Água
16.
Nature ; 607(7919): 507-511, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831505

RESUMO

The fossil record of marine invertebrates has long fuelled the debate as to whether or not there are limits to global diversity in the sea1-5. Ecological theory states that, as diversity grows and ecological niches are filled, the strengthening of biological interactions imposes limits on diversity6,7. However, the extent to which biological interactions have constrained the growth of diversity over evolutionary time remains an open question1-5,8-11. Here we present a regional diversification model that reproduces the main Phanerozoic eon trends in the global diversity of marine invertebrates after imposing mass extinctions. We find that the dynamics of global diversity are best described by a diversification model that operates widely within the exponential growth regime of a logistic function. A spatially resolved analysis of the ratio of diversity to carrying capacity reveals that less than 2% of the global flooded continental area throughout the Phanerozoic exhibits diversity levels approaching ecological saturation. We attribute the overall increase in global diversity during the Late Mesozoic and Cenozoic eras to the development of diversity hotspots under prolonged conditions of Earth system stability and maximum continental fragmentation. We call this the 'diversity hotspots hypothesis', which we propose as a non-mutually exclusive alternative to the hypothesis that the Mesozoic marine revolution led this macroevolutionary trend12,13.


Assuntos
Organismos Aquáticos , Biodiversidade , Extinção Biológica , Fósseis , Modelos Biológicos , Oceanos e Mares , Animais , Evolução Biológica , Ecologia , História Antiga , Invertebrados , Modelos Logísticos
17.
PLoS One ; 17(7): e0271556, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862366

RESUMO

The snow leopard (Panthera uncia) plays a vital role in maintaining the integrity of the high mountain ecosystem by regulating prey populations and maintaining plant community structure. Therefore, it is necessary to understand the role of the snow leopard and its interaction with prey species. Further, elucidating landscape use and co-occurrence of snow leopard and its prey species can be used to assess the differential use of habitat, allowing them to coexist. We used camera trapping and sign survey to study the interactions of snow leopard and its prey species (Siberian Ibex- Capra sibrica and Blue sheep-Pseudois nayaur) in the Spiti valley Himachal Pradesh. Using the occupancy modelling, we examined whether these prey and predator species occur together more or less frequently than would be expected by chance. To understand this, we have used ten covariates considering the ecology of the studied species. Our results suggest habitat covariates, such as LULC16 (barren area), LULC10 (grassland), ASP (aspect), SLP (slope) and DW (distance to water), are important drivers of habitat use for the snow leopard as well as its prey species. Furthermore, we found that the snow leopard detection probability was high if the site was used by its prey species, i.e., ibex and blue sheep. Whereas, in the case of the prey species, the probability of detection was low when the predator (snow leopard) was present and detected. Besides this, our results suggested that both species were less likely to detect together than expected if they were independent (Snow leopard-Ibex, Delta = 0.29, and snow leopard-blue sheep, Delta = 0.28, both the values are <1, i.e., avoidance). Moreover, despite the predation pressure, the differential anti-predation habitat selection and restriction of temporal activities by the prey species when snow leopard is present allows them to co-exist. Therefore, considering the strong link between the habitat use by the snow leopard and its prey species, it is imperative to generate quantitative long-term data on predator-prey densities and the population dynamics of its prey species in the landscape.


Assuntos
Panthera , Animais , Conservação dos Recursos Naturais , Ecologia , Ecossistema , Panthera/fisiologia , Comportamento Predatório , Ovinos
18.
Sci Rep ; 12(1): 12981, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35902737

RESUMO

Studies on time allocation of various activities are crucial to understand which behavioural strategy is the most profitable in a given context, and so why animals behave in a particular way. Such investigations usually focus on a time window when the studied activity is performed, often neglecting how the time devoted to focal activity affects time allocation to following-up behaviours, while that may have its own fitness consequences. In this study, we examined time allocation into three post-foraging activities (entering the nest with food, nest attendance, and colony attendance) in a small seabird species, the little auk (Alle alle). Since little auks alternate foraging trips of different duration (short and long) and purpose (offspring feeding and primarily self-feeding, respectively) we expected that duration of the following up in-colony activities would also vary, being longer after a long absence in the colony (because of greater need of reassessment of the current predation pressure and social interactions in the colony, and re-establishing the bond with the offspring and/or partner and/or neighbours after longer absence). We found that it was not always the case, as time allocation of the post-foraging in-colony activities was primarily year- and sex-specific. It highlights the need to consider year and sex effects in studies of behavioural ecology, as not doing so may lead to spurious conclusions. Interestingly, and despite a great inter-individual variation in time allocation in the post-foraging in-colony activities, little auk individuals were quite repeatable in their behavioural performance, which suggests these activities may reflect birds behavioural profile. Overall, post-foraging in-colony activity of the little auk, although not much dependent on duration/type of the preceding foraging flights, varies with respect to year and sex, and as such may be a proxy of behavioural plasticity of the population.


Assuntos
Charadriiformes , Comportamento Alimentar , Animais , Aves , Ecologia , Feminino , Masculino , Comportamento Predatório
19.
Am Nat ; 200(2): 250-263, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35905408

RESUMO

AbstractCrook published a landmark study on the social organization of weavers (or weaverbirds, family Ploceidae) that contributed to the emergence of sociobiology, behavioral ecology, and phylogenetic comparative methods. By comparing ecology, spatial distribution, and mating systems, Crook suggested that the spatial distribution of food resources and breeding habitats influence weaver aggregation during both the nonbreeding season (flocking vs. solitary foraging) and the breeding season (colonial vs. solitary breeding), and the latter in turn impacts mating systems and sexual selection. Although Crook's study stimulated much follow-up research, his conclusions have not been scrutinized using phylogenetically controlled analyses. We revisited Crook's hypotheses using modern phylogenetic comparative methods on an extended data set of 107 weaver species. We showed that both diet and habitat type are associated with spatial distribution and that the latter predicts mating system, consistent with Crook's propositions. The best-supported phylogenetic path model also supported Crook's arguments and uncovered a direct relationship between nonbreeding distribution and mating system. Taken together, our phylogenetically corrected analyses confirm Crook's conjectures on the roles of ecology in social organizations of weavers; however, our analyses also uncovered an association between nonbreeding distributions and mating systems, which was not envisaged by Crook.


Assuntos
Passeriformes , Seleção Sexual , Animais , Ecologia , Filogenia , Comportamento Sexual Animal
20.
Science ; 377(6604): 416-420, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35862538

RESUMO

Species' geographic ranges are limited by climate and species interactions. Climate is the prevailing explanation for why species live only within narrow elevational ranges in megadiverse biodiverse tropical mountains, but competition can also restrict species' elevational ranges. We test contrasting predictions of these hypotheses by conducting a global comparative test of birds' elevational range sizes within 31 montane regions, using more than 4.4 million citizen science records from eBird to define species' elevational ranges in each region. We find strong support that competition, not climate, is the leading driver of narrow elevational ranges. These results highlight the importance of species interactions in shaping species' ranges in tropical mountains, Earth's hottest biodiversity hotspots.


Assuntos
Altitude , Aves , Comportamento Competitivo , Animais , Biodiversidade , Ecologia , Ecossistema , Clima Tropical
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