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1.
Proc Natl Acad Sci U S A ; 121(17): e2318596121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38621142

RESUMO

While there is increasing recognition that social processes in cities like gentrification have ecological consequences, we lack nuanced understanding of the ways gentrification affects urban biodiversity. We analyzed a large camera trap dataset of mammals (>500 g) to evaluate how gentrification impacts species richness and community composition across 23 US cities. After controlling for the negative effect of impervious cover, gentrified parts of cities had the highest mammal species richness. Change in community composition was associated with gentrification in a few cities, which were mostly located along the West Coast. At the species level, roughly half (11 of 21 mammals) had higher occupancy in gentrified parts of a city, especially when impervious cover was low. Our results indicate that the impacts of gentrification extend to nonhuman animals, which provides further evidence that some aspects of nature in cities, such as wildlife, are chronically inaccessible to marginalized human populations.


Assuntos
Biodiversidade , Segregação Residencial , Animais , Humanos , Cidades , Mamíferos , Animais Selvagens , Ecossistema
2.
Proc Natl Acad Sci U S A ; 121(12): e2312252121, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38466845

RESUMO

The social system of animals involves a complex interplay between physiology, natural history, and the environment. Long relied upon discrete categorizations of "social" and "solitary" inhibit our capacity to understand species and their interactions with the world around them. Here, we use a globally distributed camera trapping dataset to test the drivers of aggregating into groups in a species complex (martens and relatives, family Mustelidae, Order Carnivora) assumed to be obligately solitary. We use a simple quantification, the probability of being detected in a group, that was applied across our globally derived camera trap dataset. Using a series of binomial generalized mixed-effects models applied to a dataset of 16,483 independent detections across 17 countries on four continents we test explicit hypotheses about potential drivers of group formation. We observe a wide range of probabilities of being detected in groups within the solitary model system, with the probability of aggregating in groups varying by more than an order of magnitude. We demonstrate that a species' context-dependent proclivity toward aggregating in groups is underpinned by a range of resource-related factors, primarily the distribution of resources, with increasing patchiness of resources facilitating group formation, as well as interactions between environmental conditions (resource constancy/winter severity) and physiology (energy storage capabilities). The wide variation in propensities to aggregate with conspecifics observed here highlights how continued failure to recognize complexities in the social behaviors of apparently solitary species limits our understanding not only of the individual species but also the causes and consequences of group formation.


Assuntos
Carnívoros , Comportamento Social , Animais , Carnívoros/fisiologia
3.
Glob Chang Biol ; 30(1): e17056, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273542

RESUMO

Ecosystem functions and services are severely threatened by unprecedented global loss in biodiversity. To counteract these trends, it is essential to develop systems to monitor changes in biodiversity for planning, evaluating, and implementing conservation and mitigation actions. However, the implementation of monitoring systems suffers from a trade-off between grain (i.e., the level of detail), extent (i.e., the number of study sites), and temporal repetition. Here, we present an applied and realized networked sensor system for integrated biodiversity monitoring in the Nature 4.0 project as a solution to these challenges, which considers plants and animals not only as targets of investigation, but also as parts of the modular sensor network by carrying sensors. Our networked sensor system consists of three main closely interlinked components with a modular structure: sensors, data transmission, and data storage, which are integrated into pipelines for automated biodiversity monitoring. We present our own real-world examples of applications, share our experiences in operating them, and provide our collected open data. Our flexible, low-cost, and open-source solutions can be applied for monitoring individual and multiple terrestrial plants and animals as well as their interactions. Ultimately, our system can also be applied to area-wide ecosystem mapping tasks, thereby providing an exemplary cost-efficient and powerful solution for biodiversity monitoring. Building upon our experiences in the Nature 4.0 project, we identified ten key challenges that need to be addressed to better understand and counteract the ongoing loss of biodiversity using networked sensor systems. To tackle these challenges, interdisciplinary collaboration, additional research, and practical solutions are necessary to enhance the capability and applicability of networked sensor systems for researchers and practitioners, ultimately further helping to ensure the sustainable management of ecosystems and the provision of ecosystem services.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Plantas
4.
Biol Lett ; 20(6): 20240069, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38889775

RESUMO

Infection risk by pathogenic agents motivates hosts to avoid using resources with high risks. This, in turn, results in increased availability of these resources for other species that are more tolerant of infections. For instance, carcasses of mammalian carnivores are frequently avoided by conspecific or closely related carnivores, allowing them to be almost exclusively used by maggots. This may lead to novel interactions with other species. This study investigated the consumption of maggots from carnivore carcasses by non-corvid passerines. We successfully monitored 66 raccoon carcasses in Hokkaido, Japan, from 2016 to 2019. Vertebrates only scavenged 14 carcasses before maggot dispersal; the other 52 carcasses produced abundant maggots that regularly fed at least 12 species of non-corvid passerines. Surprisingly, predation occurred at a distance from the carcasses, mainly after maggot dispersal for pupation, despite the higher efficiency of feeding on maggot masses on the carcasses. Birds are likely to reduce the potential risk of infection from the carcass and/or from maggots on the carcasses. Overall, only 1% of maggots were consumed. Our results suggest that necrophagous flies could benefit from the infection risk associated with carnivore carcasses, which may decrease scavenging by other carnivores and constrain maggot consumption by insectivorous birds.


Assuntos
Cadeia Alimentar , Passeriformes , Comportamento Predatório , Animais , Passeriformes/fisiologia , Guaxinins/fisiologia , Larva/fisiologia , Japão , Comportamento Alimentar
5.
Environ Manage ; 74(4): 636-647, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38851641

RESUMO

In the Mediterranean, we find a mosaic of natural and cultural landscapes, where a variety of forest management practices created intermediate disturbance regimes that potentially increased biodiversity values. Nonetheless, it is essential to understand the species' long-term response to the dynamic management in agroecosystems, since the species tolerance to disturbance can change throughout the life cycle. Mammalian carnivores can be sensitive to human disturbance and are an essential part of ecosystems due to their regulatory and community structuring effects. We investigated the spatial response of five mesocarnivores species to spatially- and temporally- varying management practices in an agroforestry landscape. More specifically, we assessed the mesocarnivores' temporal changes in space use by implementing multi-season occupancy models in a Bayesian framework, using seasonal camera-trapping surveys for a 2-year period. All species had a weak response of local extinction to forestry management and livestock grazing pressure. For forest-dwelling species, occupancy was higher where productivity of perennial vegetation was high, while colonization between seasons was positively associated with vegetation cover. For habitat generalist species, we found that occupancy in the wet season increased with the distance to cattle exclusion plots. Most of these plots are pine stands which are subject to forestry interventions during winter. During the 2-year period we found seasonal fluctuations in occupancy for all species, with an overall slight decrease for three mesocarnivore species, while for the two forest-dwelling species there was an increase in occupancy between years. The weak species response to management practices supports the importance of traditional management for upholding a diverse mesocarnivore community in agroforestry systems but could also reflect these species' ecological plasticity and resilience to disturbance.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal , Estações do Ano , Agricultura Florestal/métodos , Animais , Conservação dos Recursos Naturais/métodos , Florestas , Biodiversidade , Ecossistema , Agricultura/métodos , Teorema de Bayes
6.
Environ Monit Assess ; 196(3): 258, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349596

RESUMO

In the Azores, complaints about grape loss to birds have become recurrent. Although winegrowers frequently blame the endemic Azores Woodpigeon Columba palumbus azorica, data about the magnitude of grape damage and the species responsible for them are lacking. This study provides detailed information about grape damage caused by vertebrates on Pico Island, home to the main wine-growing area of the region. Vineyards were monitored during the ripening period in 2017 and 2018. Damage was assessed by determining the number of plucked, pecked and bitten grapes for a total of 850 bunches. Camera traps were placed in 113 enclosures providing detection and consumption rates of vertebrate species. GLM analysis was performed to test the effect of grape variety, distance to the woods, year and time before harvest on grape damage and consumption events. Damage was estimated at 10.3% (± 0.9) in 2017 and 8.7% (± 0.9) in 2018 and mostly consisted of plucked grapes. Ten vertebrate species were detected consuming grapes. Overall, 524 consumption events were registered. The Madeira lizard Teira dugesii, the Azores Blackbird Turdus merula azorensis and rodents (rats Rattus sp. and the house mouse Mus musculus) were responsible for most of those events. The Azores Woodpigeon accounted for three consumption events. GLM analysis showed that damage was greater in vines adjacent to woods and lower in traditional white varieties. This study constitutes an important baseline for the implementation of efficient measures to mitigate grape predation and sheds light on the minor role of the Azores Woodpigeon in grape damage.


Assuntos
Monitoramento Ambiental , Vinho , Camundongos , Animais , Ratos , Açores , Fazendas , Vertebrados
7.
Ecol Appl ; 33(7): e2916, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37635645

RESUMO

Outdoor recreation is increasing rapidly on public lands, with potential consequences for wildlife communities. Recreation can induce shifts in wildlife activity and habitat use, but responses vary widely even within the same species, suggesting mitigating factors that remain poorly understood. Both the type of recreation-motorized or nonmotorized-and the distance of wildlife from human disturbance may be important in developing a general understanding of recreation impacts on wildlife and making more informed management decisions. We conducted a camera-trapping survey in the Colville National Forest (CNF) of northeastern Washington in the summers of 2019 and 2020. We collected ~11,000 trap nights of spatially extensive data on nine mid-large mammalian species, simultaneously recording the presence and activity patterns of motorized (primarily vehicles on roads) and nonmotorized (primarily hikers on trails) recreation and wildlife both along trails and roads and off trails and off roads (away from most recreation). We used diel overlap analysis, time lag analysis, and single-season single-species occupancy modeling to examine the impact of recreation on the focal species. Species temporally avoided recreationists either by shifting to more nocturnal hours or delaying return to recently used recreation sites. Most species also responded spatially by altering the use or the intensity of use of camera sites due to recreation, although both positive and negative associations with recreation were documented. Species responded to nonmotorized recreation (e.g., hikers on trails) more often than motorized recreation (e.g., vehicles on roads). Most effects of recreation extended off the trail or road, although in three instances the spatiotemporal response of species to recreation along trails/roads disappeared a short distance away from those features. Our work suggests that a better understanding of landscape-scale impacts of recreation, including fitness consequences, will require additional work to disentangle the effects of different types of recreation and estimate the effective distance at which wildlife responds. Moreover, these results suggest that quiet, nonconsumptive recreation may warrant increased attention from land managers given its potential to influence the spatiotemporal ecology of numerous species.


Assuntos
Ecossistema , Recreação , Humanos , Animais , Florestas , Animais Selvagens , Mamíferos , Veículos Automotores , Conservação dos Recursos Naturais
8.
J Anim Ecol ; 92(9): 1786-1801, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37221666

RESUMO

Understanding the spatial dynamics and drivers of wildlife pathogens is constrained by sampling logistics, with implications for advancing the field of landscape epidemiology and targeted allocation of management resources. However, visually apparent wildlife diseases, when combined with remote-surveillance and distribution modelling technologies, present an opportunity to overcome this landscape-scale problem. Here, we investigated dynamics and drivers of landscape-scale wildlife disease, using clinical signs of sarcoptic mange (caused by Sarcoptes scabiei) in its bare-nosed wombat (BNW; Vombatus ursinus) host. We used 53,089 camera-trap observations from over 3261 locations across the 68,401 km2 area of Tasmania, Australia, combined with landscape data and ensemble species distribution modelling (SDM). We investigated: (1) landscape variables predicted to drive habitat suitability of the host; (2) host and landscape variables associated with clinical signs of disease in the host; and (3) predicted locations and environmental conditions at greatest risk of disease occurrence, including some Bass Strait islands where BNW translocations are proposed. We showed that the Tasmanian landscape, and ecosystems therein, are nearly ubiquitously suited to BNWs. Only high mean annual precipitation reduced habitat suitability for the host. In contrast, clinical signs of sarcoptic mange disease in BNWs were widespread, but heterogeneously distributed across the landscape. Mange (which is environmentally transmitted in BNWs) was most likely to be observed in areas of increased host habitat suitability, lower annual precipitation, near sources of freshwater and where topographic roughness was minimal (e.g. human modified landscapes, such as farmland and intensive land-use areas, shrub and grass lands). Thus, a confluence of host, environmental and anthropogenic variables appear to influence the risk of environmental transmission of S. scabiei. We identified that the Bass Strait Islands are highly suitable for BNWs and predicted a mix of high and low suitability for the pathogen. This study is the largest spatial assessment of sarcoptic mange in any host species, and advances understanding of the landscape epidemiology of environmentally transmitted S. scabiei. This research illustrates how host-pathogen co-suitability can be useful for allocating management resources in the landscape.


Assuntos
Marsupiais , Escabiose , Animais , Humanos , Escabiose/epidemiologia , Efeitos Antropogênicos , Ecossistema , Sarcoptes scabiei , Animais Selvagens
9.
Conserv Biol ; : e14221, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37937455

RESUMO

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning.


Combinación de censos con fototrampas y mapas de extensión de la UICN para incrementar el conocimiento sobre la distribución de las especies Resumen Los mapas confiables de la distribución de las especies son fundamentales para la investigación y conservación de la biodiversidad. Los mapas de distribución de la Unión Internacional para la Conservación de la Naturaleza (UICN) están reconocidos como representaciones de autoridad de los límites geográficos de las especies, aunque no siempre se alinean con los datos actuales de su presencia. En los mapas recientes de área de hábitat (ADH), las áreas que no son hábitat han sido eliminadas de la distribución de la UICN para reducir los errores de comisión, pero su concordancia con la presencia actual de las especies tampoco ha sido analizada. Analizamos la concordancia entre la presencia registrada por los censos de fototrampas y pronosticamos la presencia a partir de los mapas de la UICN y de ADH de 510 especies de mamíferos de talla mediana a grande en 80 áreas de muestreo de fototrampas. Las cámaras detectaron sólo el 39% de las especies esperadas con base en la distribución de la UICN y los mapas de ADH en todas las áreas; el 85% de las disparidades con la UICN ocurrieron dentro de los 200 km a partir del borde de la distribución. Sólo el 4% de la presencia de las especies fue detectada por las cámaras ubicadas fuera de la distribución de la UICN. La probabilidad de disparidad entre las cámaras y la UICN fue significativamente mayor para los mamíferos de talla pequeña y para los especialistas de hábitat en las regiones Neotropical e Indomalaya y en áreas con doseles forestales más bajos. Nuestros hallazgos sugieren que los mapas de distribución y ADH pocas veces subrepresentan las áreas con presencia de las especies, pero con frecuencia pueden sobrerrepresentar la distribución al incluir áreas en donde las especies pueden estar ausentes, en particular los bordes de la distribución. Sugerimos que la combinación de los mapas de distribución con los sensores de biodiversidad en tierra, como las fototrampas, proporciona una base más rica de conocimiento para el mapeo y la planeación de la conservación.

10.
Oecologia ; 202(3): 523-533, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37380736

RESUMO

Nurse plants provide benefits during the early life cycle of the protected plant by reducing the intensity of stressful abiotic conditions. However, nurse plants may influence frugivore visitation and consumption, affecting the initial benefits of this interaction and generating different frugivory patterns during the reproductive phase of the protégé. Despite the importance of nurse plants and frugivory in the structure and composition of ecosystems, they have rarely been evaluated together, and frugivory patterns caused by nurse plants at different spatial and temporal scales are mostly unknown. Pilosocereus leucocephalus produces seeds that are endozoochorically dispersed by birds and mammals, can establish in open spaces devoid of arboreal vegetation (OS), and is associated with the nurse tree Lysiloma acapulcensis. However, the influence of L. acapulcensis on the frugivory patterns of P. leucocephalus is unknown. Therefore, during the fruiting season of P. leucocephalus of 2018, we recorded the visitation rates, effective removal, and removal timescales in 26 individuals located in OS and 15 under L. acapulcensis. Our results indicate that L. acapulcensis increased visits by Euphonia hirundinacea and bats but decreased those of Psilorhinus morio and Campylorhynchus rufinucha. Although L. acapulcensis did not generate differences in fruit removal effectiveness, bats showed the highest effectiveness in OS, followed by birds. L. acapulcensis also had an effect on the fruit removal periods of different frugivorous species at different temporal scales. This shows that the nurse tree generated a complex pattern of frugivory in P. leucocephalus, mainly increasing the initial benefits of the nurse-protégé interaction.


Assuntos
Cactaceae , Quirópteros , Dispersão de Sementes , Humanos , Animais , Ecossistema , Sementes , Frutas , Plantas , Árvores , Aves , Comportamento Alimentar
11.
J Anim Ecol ; 91(1): 46-60, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34689337

RESUMO

Spatiotemporal variation in predation risk arises from interactions between landscape heterogeneity, predator densities and predator hunting mode, generating landscapes of fear for prey species that can have important effects on prey behaviour and ecosystem dynamics. As widespread apex predators, humans present a significant source of risk for hunted animal populations. Spatiotemporal patterns of risk from hunters can overlap or contrast with patterns of risk from other predators. Human infrastructure can also reshape spatial patterns of risk by facilitating or impeding hunter or predator movement, or deterring predators that are themselves wary of humans. We examined how anthropogenic and natural landscape features interact with hunting modes of rifle hunters and mountain lions Puma concolor to generate spatiotemporal patterns of risk for their primary prey. We explored the implications of human-modified landscapes of fear for Columbian black-tailed deer Odocoileus hemionus columbianus in Mendocino County, California. We used historical harvest records, hunter GPS trackers and camera trap records of mountain lions to model patterns of risk for deer. We then used camera traps to examine deer spatial and temporal activity patterns in response to this variation in risk. Hunters and mountain lions exhibited distinct, contrasting patterns of spatiotemporal activity. Risk from rifle hunters, who rely on long lines of sight, was highest in open grasslands and near roads and was confined to the daytime. Risk from mountain lions, an ambush predator, was highest in dense shrubland habitat, farther from developed areas, and during the night and crepuscular periods. Areas of human settlement provided a refuge from both hunters and mountain lions. We found no evidence that deer avoided risk in space at the scale of our observations, but deer adjusted their temporal activity patterns to reduce the risk of encounters with humans and mountain lions in areas of higher risk. Our study demonstrates that interactions between human infrastructure, habitat cover and predator hunting mode can result in distinct spatial patterns of predation risk from hunters and other predators that may lead to trade-offs for prey species. However, distinct diel activity patterns of predators may create vacant hunting domains that reduce costly trade-offs for prey. Our study highlights the importance of temporal partitioning as a mechanism of predation risk avoidance.


Assuntos
Cervos , Puma , Animais , Ecossistema , Medo , Humanos , Comportamento Predatório/fisiologia , Puma/fisiologia
12.
J Anim Ecol ; 91(2): 367-380, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34775595

RESUMO

Studying species interactions and niche segregation under human pressure provides important insights into species adaptation, community functioning and ecosystem stability. Due to their high plasticity in behaviour and diet, urban mesocarnivores are ideal species for studying community assembly in novel communities. We analysed the spatial and temporal species interactions of an urban mesocarnivore community composed of the red fox Vulpes vulpes and the marten Martes sp. as native species, the raccoon Procyon lotor as invasive species, and the cat Felis catus as a domestic species in combination with human disturbance modulated by the SARS-CoV-2 lockdown effect that happened while the study was conducted. We analysed camera trap data and applied a joint species distribution model to understand not only the environmental variables influencing the detection of mesocarnivores and their use intensity of environmental features but also the species' co-occurrences while accounting for environmental variables. We then assessed whether they displayed temporal niche partitioning based on activity analyses, and finally analysed at a smaller temporal scale the time of delay after the detection of another focal species. We found that species were more often detected and displayed a higher use intensity in gardens during the SARS-CoV-2 lockdown period, while showing a shorter temporal delay during the same period, meaning a high human-induced spatiotemporal overlap. All three wild species spatially co-occurred within the urban area, with a positive response of raccoons to cats in detection and use intensity, whereas foxes showed a negative trend towards cats. When assessing the temporal partitioning, we found that all wild species showed overlapping nocturnal activities. All species displayed temporal segregation based on temporal delay. According to the temporal delay analyses, cats were the species avoided the most by all wild species. To conclude, we found that although the wild species were positively associated in space, the avoidance occurred at a smaller temporal scale, and human pressure in addition led to high spatiotemporal overlap. Our study sheds light to the complex patterns underlying the interactions in a mesocarnivore community both spatially and temporally, and the exacerbated effect of human pressure on community dynamics.


Assuntos
Gatos , Raposas , Mustelidae , Guaxinins , Animais , Comportamento Animal , COVID-19 , Cidades , Controle de Doenças Transmissíveis , Ecossistema , Humanos , Análise Espaço-Temporal
13.
Conserv Biol ; 36(3): e13839, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34533235

RESUMO

In the Anthropocene, understanding the impacts of anthropogenic influence on biodiversity and behavior of vulnerable wildlife communities is increasingly relevant to effective conservation. However, comparative studies aimed at disentangling the concurrent effect of different types of human disturbance on multifaceted biodiversity and on activity patterns of mammals are surprisingly rare. We applied a multiregion community model to separately estimate the effects of cumulative human modification (e.g., settlement, agriculture, and transportation) and human presence (aggregated presence of dogs, people, and livestock) on species richness and functional composition of medium- and large-bodied mammals based on camera trap data collected across 45 subtropical montane forests. We divided the detected mammal species into three trophic guilds-carnivores, herbivores, and omnivores-and assessed the nocturnal shifts of each guild in response to anthropogenic activities. Overall, species richness tended to increase (ß coefficient = 0.954) as human modification increased but richness decreased as human presence increased (ß = -1.054). Human modification was associated with significantly lower functional diversity (mean nearest taxon distance [MNTD], ß = -0.134; standardized effect sizes of MNTD, ß = -0.397), community average body mass (ß = -0.240), and proportion of carnivores (ß = -0.580). Human presence was associated with a strongly reduced proportion of herbivores (ß = -0.522), whereas proportion of omnivores significantly increased as human presence (ß = 0.378) and habitat modification (ß = 0.419) increased. In terms of activity patterns, omnivores (ß = 12.103) and carnivores (ß = 9.368) became more nocturnal in response to human modification. Our results suggest that human modification and human presence have differing effects on mammals and demonstrate that anthropogenic disturbances can lead to drastic loss of functional diversity and result in a shift to nocturnal behavior of mammals. Conservation planning should consider concurrent effects of different types of human disturbance on species richness, functional diversity, and behavior of wildlife communities.


Pérdidas en la Diversidad Funcional y Cambios en el Comportamiento Nocturno de los Mamíferos bajo la Perturbación Antropogénica Resumen En el Antropoceno, el conocimiento sobre la influencia antropogénica sobre la biodiversidad y el comportamiento de las comunidades vulnerables de fauna es cada vez más relevante para la conservación efectiva. Sin embargo, sorprende que los estudios comparativos dirigidos a desentrañar el efecto concurrente de los diferentes tipos de perturbación humana sobre la biodiversidad multifacética y sobre los patrones de actividad de los mamíferos son escasos. Aplicamos un modelo de comunidad multirregional para estimar de manera separada los efectos de la modificación humana (p. ej.: establecimientos, agricultura, transporte) y la presencia humana (presencia agregada de perros, gente y ganado) acumuladas sobre la riqueza de especies y la composición funcional de los mamíferos de tamaño mediano y grande con base en datos de fototrampas recolectados en 45 bosques montanos subtropicales. Dividimos las especies de mamíferos detectadas en tres gremios tróficos: carnívoros, herbívoros y omnívoros, y analizamos los cambios nocturnos de cada gremio como respuesta a las actividades antropogénicas. En general, la riqueza de especies tuvo una tendencia al incremento (coeficiente ß = 0.954) conforme aumentaron las modificaciones humanas, pero la riqueza disminuyó conforme incrementó la presencia humana (ß = −1.054). Las modificaciones humanas estuvieron asociadas con una diversidad funcional (distancia promedio al taxón más cercano [DPTC], ß = −0.134; tamaños del efecto estandarizado de la DPTC, ß = −0.397), masa corporal promedio de la comunidad (ß = −0.240) y proporción de carnívoros (ß = −0.580) significativamente más bajas. La presencia humana estuvo asociada con una proporción gravemente reducida de herbívoros (ß = −0.522), mientras que la proporción de omnívoros incrementó significativamente conforme aumentaron la presencia humana (ß = 0.378) y la modificación del hábitat (ß = 0.419). En cuanto a los patrones de actividad, los omnívoros (ß = 12.103) y los carnívoros (ß = 9.368) se volvieron más nocturnos como respuesta a las modificaciones humanas. Nuestros resultados sugieren que las modificaciones humanas y la presencia de personas tienen efectos diferentes sobre los mamíferos y demuestran que las perturbaciones antropogénicas pueden llevar a pérdidas drásticas de la diversidad funcional y resultar en un cambio hacia el comportamiento nocturno en los mamíferos. La planeación de la conservación debería considerar los efectos concurrentes de los diferentes tipos de perturbaciones humanas sobre la riqueza de especies, la diversidad funcional y el comportamiento de las comunidades faunísticas.


Assuntos
Efeitos Antropogênicos , Conservação dos Recursos Naturais , Animais , Animais Selvagens , Biodiversidade , Conservação dos Recursos Naturais/métodos , Cães , Ecossistema , Humanos , Mamíferos/fisiologia
14.
J Insect Sci ; 22(5)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256385

RESUMO

Navel orangeworm, Amyelois transitella (Walker), is a key pest of walnuts, pistachio, and almonds in California. Pheromone mating disruption using timed aerosol dispensers is an increasingly common management technique. Dispenser efficiency may be increased by timing releases with the active mating period of navel orangeworm. Past work found that the peak time of sexual activity for navel orangeworm females is 2 h before sunrise when temperatures are above 18°C. Inference of male responsiveness from data collected in that study was limited by the necessity of using laboratory-reared females as a source of sex pheromone emission to attract males and the inherent limitations of human observers for nocturnal events. Here we used camera traps baited with artificial pheromone to observe male navel orangeworm mating response in the field over two field seasons. Male response to synthetic pheromone exhibited diel patterns broadly similar to females, i.e., they were active for a brief period of 2-3 h before dawn under summer conditions and began responding to pheromone earlier and over a longer period of time during spring and fall. But contrary to the previous findings with females, some males were captured at all hours of the day and night, and there was no evidence of short-term change of pheromone responsiveness in response to temperature. Environmental effects on the response of navel orangeworm males to an artificial pheromone source differ in important ways from the environmental effects on female release of sex pheromone.


Assuntos
Mariposas , Prunus dulcis , Atrativos Sexuais , Humanos , Masculino , Feminino , Animais , Atrativos Sexuais/farmacologia , Mariposas/fisiologia , Feromônios/farmacologia , Aerossóis
15.
Eur J Wildl Res ; 68(6): 69, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213142

RESUMO

Contact between wild animals and farmed livestock may result in disease transmission with huge financial, welfare and ethical consequences. Conflicts between people and wildlife can also arise when species such as wild boar (Sus scrofa) consume crops or dig up pasture. This is a relatively recent problem in England where wild boar populations have become re-established in the last 20 years following a 500-year absence. The aim of this pilot study was to determine if and how often free-living wild boar visited two commercial pig farms near the Forest of Dean in southwest England. We placed 20 motion-sensitive camera traps at potential entry points to, and trails surrounding, the perimeter of two farmyards housing domestic pigs between August 2019 and February 2021, covering a total of 6030 trap nights. Forty wild boar detections were recorded on one farm spread across 27 nights, with a median (range) of 1 (0 to 7) night of wild boar activity per calendar month. Most of these wild boar detections occurred between ten and twenty metres of housed domestic pigs. No wild boar was detected at the other farm. These results confirm wild boar do visit commercial pig farms, and therefore, there is potential for contact and pathogen exchange between wild boar and domestic pigs. The visitation rates derived from this study could be used to parameterise disease transmission models of pathogens common to domestic pigs and wild boars, such as the African swine fever virus, and subsequently to develop mitigation strategies to reduce unwanted contacts.

16.
Proc Biol Sci ; 288(1946): 20202379, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33715442

RESUMO

Apex predator reintroductions have proliferated across southern Africa, yet their ecological effects and proposed umbrella benefits of associated management lack empirical evaluations. Despite a rich theory on top-down ecosystem regulation via mesopredator suppression, a knowledge gap exists relating to the influence of lions (Panthera leo) over Africa's diverse mesocarnivore (less than 20 kg) communities. We investigate how geographical variation in mesocarnivore community richness and occupancy across South African reserves is associated with the presence of lions. An interesting duality emerged: lion reserves held more mesocarnivore-rich communities, yet mesocarnivore occupancy rates and evenness-weighted diversity were lower in the presence of lions. Human population density in the reserve surroundings had a similarly ubiquitous negative effect on mesocarnivore occupancy. The positive association between species richness and lion presence corroborated the umbrella species concept but translated into small differences in community size. Distributional contractions of mesocarnivore species within lion reserves, and potentially corresponding numerical reductions, suggest within-community mesopredator suppression by lions, probably as a result of lethal encounters and responses to a landscape of fear. Our findings offer empirical support for the theoretical understanding of processes underpinning carnivore community assembly and are of conservation relevance under current large-predator orientated management and conservation paradigms.


Assuntos
Carnívoros , Leões , África , Animais , Ecossistema , Geografia , Humanos
17.
Ecol Appl ; 31(2): e02253, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33141996

RESUMO

Understanding how biodiversity responds to urbanization is challenging, due in part to the single-city focus of most urban ecological research. Here, we delineate continent-scale patterns in urban species assemblages by leveraging data from a multi-city camera trap survey and quantify how differences in greenspace availability and average housing density among 10 North American cities relate to the distribution of eight widespread North American mammals. To do so, we deployed camera traps at 569 sites across these ten cities between 18 June and 14 August. Most data came from 2017, though some cities contributed 2016 or 2018 data if it was available. We found that the magnitude and direction of most species' responses to urbanization within a city were associated with landscape-scale differences among cities. For example, eastern gray squirrel (Sciurus carolinensis), fox squirrel (Sciurus niger), and red fox (Vulpes vulpes) responses to urbanization changed from negative to positive once the proportion of green space within a city was >~20%. Likewise, raccoon (Procyon lotor) and Virginia opossum (Didelphis virginiana) responses to urbanization changed from positive to negative once the average housing density of a city exceeded about 700 housing units/km2 . We also found that local species richness within cities consistently declined with urbanization in only the more densely developed cities (>~700 housing units/km2 ). Given our results, it may therefore be possible to design cities to better support biodiversity and reduce the negative influence of urbanization on wildlife by, for example, increasing the amount of green space within a city. Additionally, it may be most important for densely populated cities to find innovative solutions to bolster wildlife resilience because they were the most likely to observe diversity losses of common urban species.


Assuntos
Ecossistema , Urbanização , Animais , Biodiversidade , Cidades , Mamíferos
18.
Ecol Appl ; 31(8): e02436, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34374154

RESUMO

Biological data collection is entering a new era. Community science, satellite remote sensing (SRS), and local forms of remote sensing (e.g., camera traps and acoustic recordings) have enabled biological data to be collected at unprecedented spatial and temporal scales and resolution. There is growing interest in developing observation networks to collect and synthesize data to improve broad-scale ecological monitoring, but no examples of such networks have emerged to inform decision-making by agencies. Here, we present the implementation of one such jurisdictional observation network (JON), Snapshot Wisconsin, which links synoptic environmental data derived from SRS to biodiversity observations collected continuously from a trail camera network to support management decision-making. We use several examples to illustrate that Snapshot Wisconsin improves the spatial, temporal, and biological resolution and extent of information available to support management, filling gaps associated with traditional monitoring and enabling consideration of new management strategies. JONs like Snapshot Wisconsin further strengthen monitoring inference by contributing novel lines of evidence useful for corroboration or integration. SRS provides environmental context that facilitates inference, prediction, and forecasting, and ultimately helps managers formulate, test, and refine conceptual models for the monitored systems. Although these approaches pose challenges, Snapshot Wisconsin demonstrates that expansive observation networks can be tractably managed by agencies to support decision making, providing a powerful new tool for agencies to better achieve their missions and reshape the nature of environmental decision-making.


Assuntos
Biodiversidade , Tecnologia de Sensoriamento Remoto , Monitoramento Ambiental , Modelos Teóricos , Wisconsin
19.
J Anim Ecol ; 90(8): 1973-1984, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942308

RESUMO

Camera traps are an increasingly popular tool to monitor wildlife distributions. However, traditional analytical approaches to camera trap data are difficult to apply to visible wildlife characteristics in single images, such as infection status. Several parasites produce visible signs of infection that could be sampled via camera traps. Sarcoptic mange Sarcoptes scabiei is an ideal disease to study using cameras because it results in visible hair loss and affects a broad host range. Here, we developed a multi-state occupancy model to estimate the occurrence of mange in coyotes Canis latrans across an urban gradient. This model incorporates a secondary detection function for apparent by-image infection status to provide detection-corrected estimates of mange occurrence. We analysed a multi-year camera trap dataset in Chicago, Illinois, United States, to test whether the apparent occurrence of sarcoptic mange in coyotes Canis latrans increases with urbanization or varies through time. We documented visible signs consistent with current or recovering mange infection and variables we hypothesized would improve mange detection: The proportion of the coyote in frame, image blur and whether the image was in colour. We were more likely to detect coyotes with mange in images that were less blurry, in colour, and if a greater proportion of the coyote was visible. Mangy coyote occupancy was significantly higher in urban developed areas with low housing density and higher canopy cover whereas coyote occupancy, mangy or otherwise, decreased with urbanization. By incorporating image quality into our by-image detection function, we provide a robust method to non-invasively survey visible aspects of wildlife health with camera traps. Apparently mangy coyotes were associated with low-density forested neighbourhoods, which may offer vegetated areas while containing sources of anthropogenic resources. This association may contribute to human-wildlife conflict and reinforces posited relationships between infection risk and habitat use. More generally, our model could provide detection-corrected occupancy estimates of visible characteristics that vary by image such as body condition or injuries.


Assuntos
Coiotes , Escabiose , Animais , Animais Selvagens , Humanos , Sarcoptes scabiei , Escabiose/veterinária , Urbanização
20.
Proc Natl Acad Sci U S A ; 115(25): E5716-E5725, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29871948

RESUMO

Having accurate, detailed, and up-to-date information about the location and behavior of animals in the wild would improve our ability to study and conserve ecosystems. We investigate the ability to automatically, accurately, and inexpensively collect such data, which could help catalyze the transformation of many fields of ecology, wildlife biology, zoology, conservation biology, and animal behavior into "big data" sciences. Motion-sensor "camera traps" enable collecting wildlife pictures inexpensively, unobtrusively, and frequently. However, extracting information from these pictures remains an expensive, time-consuming, manual task. We demonstrate that such information can be automatically extracted by deep learning, a cutting-edge type of artificial intelligence. We train deep convolutional neural networks to identify, count, and describe the behaviors of 48 species in the 3.2 million-image Snapshot Serengeti dataset. Our deep neural networks automatically identify animals with >93.8% accuracy, and we expect that number to improve rapidly in years to come. More importantly, if our system classifies only images it is confident about, our system can automate animal identification for 99.3% of the data while still performing at the same 96.6% accuracy as that of crowdsourced teams of human volunteers, saving >8.4 y (i.e., >17,000 h at 40 h/wk) of human labeling effort on this 3.2 million-image dataset. Those efficiency gains highlight the importance of using deep neural networks to automate data extraction from camera-trap images, reducing a roadblock for this widely used technology. Our results suggest that deep learning could enable the inexpensive, unobtrusive, high-volume, and even real-time collection of a wealth of information about vast numbers of animals in the wild.


Assuntos
Animais Selvagens/fisiologia , Comportamento Animal/fisiologia , Algoritmos , Animais , Inteligência Artificial , Ecologia/métodos , Ecossistema , Humanos , Aprendizado de Máquina , Redes Neurais de Computação
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