5 research outputs found
The influence of domestic dogs (Canis familiaris) on the spatial and temporal distribution of tayra (Eira barbara)
No full textO cão doméstico (Canis familiaris) é uma espécie exótica conhecida por ter impactos na fauna nativa, podendo levar outras espécies à segregação espacial e temporal como mecanismo de reduzir interações agonísticas. A irara (Eira barbara), um mustelídeo de porte médio, de ampla distribuição, é umas das espécies que pode ser afetada apresentando segregação espacial ou temporal. Para testar esta hipótese, instalei armadilhas fotográficas em uma paisagem agrícola composta por uma Unidade de Conservação, plantação de café e canavial, uma área urbana e vários domicílios rurais. Calculei os padrões de atividades, seus coeficientes de sobreposição e gerei modelos para explicar a ocupação das espécies e verificar possíveis interferências. Obtive 32 registros de iraras e 100 de cães-domésticos. Em apenas 8 pontos, as duas espécies ocorreram concomitantemente. A sobreposição da atividade foi de 68%; entretanto, nos pontos onde ambas as espécies ocorreram, a porcentagem foi de 43%, sendo que a atividade da irara foi deslocada para o período matutino enquanto os cães-domésticos estiveram ativos ao longo de todo o dia, incluindo muitos registros noturnos. Em relação ao uso do espaço, a irara demonstrou estar positivamente associada a áreas de floresta, e negativamente a áreas de exploração agrícola. Cães ocuparam predominantemente áreas agrícolas, estando negativamente relacionados a áreas florestais. A presença concomitante das duas espécies teve um efeito negativo na ocupação das iraras nas áreas florestais. Além da interferência do cão, que parece interferir no uso da paisagem pela irara, as condições ambientais também são essenciais para descrever a ocupação da espécie subordinada. É possível que seu hábito escansorial seja importante para evitar eventos agonísticos.The domestic dog (Canis familiaris) is an exotic species known to have impacts on native fauna, and may lead other species to spatial and temporal segregation as a mechanism to reduce agonistic interactions. The tayra (Eira barbara), a medium-sized, widely distributed mustelid, is one of the species that can be affected by showing spatial or temporal segregation. To test this hypothesis, I installed camera traps in an agricultural landscape composed of a Conservation Unit, a coffee and sugarcane plantation, an urban area and several rural households. I calculated the activity patterns, their overlapping coefficients and generated models to explain the occupation of the species and verify possible interferences. I obtained 32 records of tayras and 100 of domestic dogs. In only 8 points, the two species occurred concomitantly. Activity overlap was 68%; however, at the points where both species occurred, the percentage was 43%, whereas tayra activity was shifted to the morning period while domestic dogs were active throughout the day, including many nocturnal records. Regarding the use of space, the tayra proved to be positively associated with forest areas, and negatively with agricultural exploration areas. Dogs predominantly occupied agricultural areas, being negatively related to forest areas. In addition to dog interference, which seems to interfere with the tayra's use of the landscape, environmental conditions are also essential to describe the occupation of the subordinate species. It is possible that their scansorial habit is important to avoid agonistic events.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Capes: 00
The effect of domestic dogs on the activity pattern of pacas and agoutis
No full textO cão doméstico (Canis familiaris) é uma espécie exótica que já contribuiu para a extinção de 11 espécies de vertebrados ao redor do mundo, e é considerado uma ameaça para cerca de outras 188. O aumento das populações dos cães domésticos têm levado a uma progressão de estudos em busca de informações sobre suas interações com mamíferos selvagens de vida livre. No entanto, no Brasil ainda há poucos estudos focados no impacto dos cães sobre mamíferos silvestres. Pacas e cutias estão entre as espécies afetadas pelos cães domésticos, tanto pela predação direta, como por alterações no comportamento, em função de perseguição. Assim, avaliei se os cães domésticos afetam o horário de atividade de pacas e cutias em diferentes Unidades de Conservação do estado de São Paulo e Rio de Janeiro. Comparei o horário de atividade de pacas e cutias com o de cães domésticos e de outras espécies, por meio de registros de armadilhas fotográficas instaladas no período de 2011 a 2021. Foi usado diferentes abordagens para avaliar como os cães afetam as atividades da paca e cutia: comparando padrões de atividade com estimativas de densidade de kernel, calculando taxas de atração-evitação e a atividade da paca nas fases lunares. Os resultados mostram que pacas e cutias mantiveram seus padrões de atividade típicos para a espécie. E não mostraram evitação em relação aos cães do que predadores naturais ou espécies não predadoras. Além disso, a atividade da paca e cutia não foi significativamente influenciada pela detecção de cães ou predadores naturais, e fatores como abundância de detecção de cães não afetaram a diferença de tempo entre as passagens das espécies após a detecção do cão. As pacas se mostraram mais ativa em luas de menor incidência lunar. Essa falta de resposta pode resultar em altos custos de energia para alterar os padrões de atividade para homeotérmicos; estratégias anti predação eficazes já usadas contra predadores nativos e cães evitando presas espacialmente em vez de temporalmente. Esse estudo é de extrema importância para compreender a ameaça de cães nas Unidades de Conservação bem como em um futuro planejamento de medidas de manejo e conservação para diversas espécies.The domestic dog (Canis familiaris) is an exotic species that has already contributed to the extinction of 11 vertebrate species worldwide and is considered a threat to about 188 others. The increase in domestic dog populations has led to a growing body of studies seeking information about their interactions with wild free-living mammals. However, in Brazil, there are still few studies focusing on the impact of dogs on wild mammals. Pacas and agoutis are among the species affected by domestic dogs, both by direct predation and by changes in behavior due to persecution. Thus, I assessed whether domestic dogs affect the activity timing of pacas and agoutis in different Conservation Units in the states of São Paulo and Rio de Janeiro. I compared the activity timing of pacas and agoutis with that of domestic dogs and other species using camera trap records collected between 2011 and 2021. Different approaches were used to assess how dogs affect the activity patterns of pacas and agoutis: comparing activity patterns with kernel density estimates, calculating attraction-avoidance rates, and evaluating paca activity across lunar phases. The results show that pacas and agoutis maintained their typical activity patterns for the species and did not show avoidance of dogs compared to natural predators or non-predatory species. Additionally, the activity of pacas and agoutis was not significantly influenced by the detection of dogs or natural predators, and factors such as the abundance of dog detections did not affect the time difference between species’ passages after dog detection. Pacas were more active during phases of the moon with lower lunar illumination. This lack of response may result in high energy costs for altering activity patterns for homeotherms; anti-predation strategies already used against native predators and dogs avoid prey spatially rather than temporally. This study is of great importance for understanding the threat of dogs in Conservation Units as well as for future management and conservation planning for various speciesFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)2021/13039-
The influence of domestic dogs on the spatial and temporal distribution of tayra
No full textThe domestic dog Canis familiaris is an exotic species known to have impacts on native fauna and it may induce spatial and temporal segregation in other species as a mechanism to reduce agonistic interactions. The tayra Eira barbara, a medium-sized, widely distributed mustelid, is one of the species that can be affected. To test this hypothesis, between 2020 and 2022, we installed camera traps in an agricultural landscape composed of a protected area, agro-livestock areas, an urban area, and several rural households. We calculated the activity patterns, their overlapping coefficients and generated models to explain the species's occupancy and verify possible interferences. We obtained 32 records of tayras and 100 of domestic dogs. In only 8 of 73 sampling points, the two species occurred concomitantly. Activity overlap was 68%; however, at the points where both species occurred, the overlap was 43%. Tayra showed to be positively associated with forest areas, and negatively with agricultural exploitation areas. Dogs predominantly occupied agricultural areas and were negatively related to forest areas. In addition to dog interference, which seems to affect tayra's use of the landscape, environmental conditions are also essential in describing the occupancy of the subordinate species. It is possible that their scansorial habit is important to avoid agonistic events.Programa de Pós-Graduação em Biodiversidade Universidade Estadual Paulista-Unesp, SPDepartamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista-Unesp, SPPrograma de Pós-Graduação em Biodiversidade Universidade Estadual Paulista-Unesp, SPDepartamento de Biologia Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista-Unesp, S
Testing the accuracy of wearable technology to assess sleep behaviour in domestic dogs: a prospective tool for animal welfare assessment in kennels
No full textSleep is a physiological process that has been shown to impact both physical and psychological heath of individuals when compromised; hence, it has the potential to be used as an indicator of animal welfare. Nonetheless, evaluating sleep in non-human species normally involves manipulation of the subjects (i.e., placement of electrodes on the cranium), and most studies are conducted in a laboratory setting, which limits the generalisability of information obtained, and the species investigated. In this study, we evaluated an alternative method of assessing sleep behaviour in domestic dogs, using a wearable sensor, and compared the measurements obtained to behavioural observations to evaluate accuracy. Differences between methods ranged from 0.13% to 59.3% for diurnal observations and 0.1% to 95.9% for nocturnal observations for point-by-point observations. Comparisons between methods showed significant differences in certain behaviours, such as inactivity and activity for diurnal recordings. However, total activity and total sleep recorded did not differ statistically between methods. Overall, the wearable technology tested was found to be a useful, and a less-time consuming, tool in comparison to direct behavioural observations for the evaluation of behaviours and their indication of wellbeing in dogs. The agreement between the wearable technology and directly observed data ranged from 75% to 99% for recorded behaviours, and these results are similar to previous findings in the literature
Testing the Accuracy of Wearable Technology to Assess Sleep Behaviour in Domestic Dogs: A Prospective Tool for Animal Welfare Assessment in Kennels
No full textSleep is a physiological process that has been shown to impact both physical and psychological heath of individuals when compromised; hence, it has the potential to be used as an indicator of animal welfare. Nonetheless, evaluating sleep in non-human species normally involves manipulation of the subjects (i.e., placement of electrodes on the cranium), and most studies are conducted in a laboratory setting, which limits the generalisability of information obtained, and the species investigated. In this study, we evaluated an alternative method of assessing sleep behaviour in domestic dogs, using a wearable sensor, and compared the measurements obtained to behavioural observations to evaluate accuracy. Differences between methods ranged from 0.13% to 59.3% for diurnal observations and 0.1% to 95.9% for nocturnal observations for point-by-point observations. Comparisons between methods showed significant differences in certain behaviours, such as inactivity and activity for diurnal recordings. However, total activity and total sleep recorded did not differ statistically between methods. Overall, the wearable technology tested was found to be a useful, and a less-time consuming, tool in comparison to direct behavioural observations for the evaluation of behaviours and their indication of wellbeing in dogs. The agreement between the wearable technology and directly observed data ranged from 75% to 99% for recorded behaviours, and these results are similar to previous findings in the literature
