Browsing by Author "Galvez, Nicolas"
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- ItemForest cover outside protected areas plays an important role in the conservation of the Vulnerable guina Leopardus guigna(2013) Galvez, Nicolas; Hernandez, Felipe; Laker, Jerry; Gilabert, Horacio; Petitpas, Robert; Bonacic Salas, Cristian; Gimona, Alessandro; Hester, Alison; Macdonald, David W.
- ItemLand use intensification coupled with free-roaming dogs as potential defaunation drivers of mesocarnivores in agricultural landscapes(WILEY, 2021) Galvez, Nicolas; Infante, Jose; Fernandez, Adrian; Diaz, Jesus; Petracca, LisanneLand use intensification, by which habitat loss, habitat fragmentation and increased land ownership subdivision occurs, represents one of the largest threats to biodiversity. The extent to which land use intensification affects the presence of native mesocarnivores is largely unexplored, with great implications for all working landscapes where agriculture and native wildlife co-occur. We obtained mesocarnivore detection/non-detection data from 180 4-km(2) sampling units in agricultural landscapes of southern Chile from January to April 2019. We used these data to (a) investigate the associations of private land ownership subdivision, forest fragmentation and forest loss with the occurrence of mesocarnivores using single-species occupancy models, (b) assess patterns of mesocarnivore co-occurrence with free-roaming domestic mesocarnivores (e.g. cats and dogs) using two-species occupancy models and (c) determine whether co-occurrence of native and domestic mesocarnivores led to alterations in species' temporal activity. Land ownership subdivision, rather than habitat loss or fragmentation, had the greatest impact on native mesocarnivore occurrence, with some influence of domestic dogs. Mesocarnivore community occurrence varied from a native to domestic species composition as private land ownership subdivision increased. Native mesocarnivores altered their behaviour temporally when co-occurring with domestics. Lastly, the presence of domestic dogs was associated with an absence of native mesocarnivores, which merits further investigation into the contribution of domestic dogs to a defaunation process in agricultural areas. Policy implications. Our evidence supports focusing efforts in three key dimensions to advance biodiversity conservation in agricultural landscapes. First, private land subdivision represents a robust proxy for measuring anthropogenic impacts on mesocarnivores, and we advocate its use to inform agricultural policy to mitigate a potential defaunation process. Second, there is a need to further engage with landowners and evaluate values, motivation, willingness and action to protect remnant native vegetation and slow land use change. And, lastly, improvements to legislation and conservation marketing strategies on responsible pet ownership are critical to ameliorating the negative impacts of dogs on native wildlife species.
- ItemRavines as conservation strongholds for small wildcats under pressure from free-ranging dogs and cats in Mediterranean landscapes of Chile(TAYLOR & FRANCIS LTD, 2021) Beltrami, Esperanza; Galvez, Nicolas; Osorio, Christian; Kelly, Marcella J.; Morales Moraga, David; Bonacic, CristianThe Chilean Mediterranean ecosystem is threatened by anthropogenic pressures, such as habitat loss by intensive agriculture and urban sprawl. Abandoned dogs (Canis lupus familiaris) and cats (Felis silvestris catus) pose conservation challenges for Chilean wildlife including the pampas cat (Leopardus colocolo) and the guina (Leopardus guigna). We used camera trap data to investigate influences of natural and anthropogenic landscape features on spatiotemporal trends of these species. We also used co-occurrence modeling and kernel density estimation to investigate spatial and temporal patterns overlap of wildcats, free-ranging (FR) dogs, and FR-cats. FR-dogs showed the highest detection and site use probabilities, while guinas had the lowest across 80 camera trap sites. Top models showed no spatial avoidance between species and co-occurrence of wildcats was positively influenced by forest habitat. However, FR-dogs negatively affected detection of wildcats. Ravines surrounded by forest positively influenced guina and pampas cat detection probabilities when dominant species were not present. FR-dogs and wildcats had significantly different temporal activity patterns and low overlap coefficients, while wildcats and FR-cats showed high overlap in activity patterns. We suggest changing current policies to control domestic animals and strategic planning in agricultural areas of central Chile to better conserve native wildcat species.
- ItemRelationship between fragmentation, degradation and native and exotic species richness in an Andean temperate forest of Chile(2011) Rojas, Isabel; Becerra, Pablo; Galvez, Nicolas; Laker, Jerry; Bonacic Salas, Cristian; Hester, Alison
- ItemResponse of mesocarnivores to anthropogenic landscape intensification: activity patterns and guild temporal interactions(OXFORD UNIV PRESS INC, 2021) Galvez, Nicolas; Meniconi, Paola; Infante, Jose; Bonacic, CristianCarnivores face important anthropogenic threats in agricultural areas from habitat loss and fragmentation, disturbance by domestic free-roaming dogs and cats, and direct hunting by humans. Anthropogenic disturbances are shifting the activity patterns of wild animals, likely modifying species interactions. We estimated changes in the activity patterns of the mesocarnivore guild of agricultural landscapes of the La Araucania region in southern Chile in response to land-use intensification, comparing intra- and interspecific activity patterns at low and high levels of forest cover, fragmentation, and land ownership subdivision. Our focal species comprise the guina or kod-kod (Leopardus guigna), two fox species (Lycalopex culpaeus and L. griseus), a skunk (Conepatus chinga), and one native mustelid (Galictis cuja), in addition to free-roaming dogs (Canis lupus familiaris) and cats (Felis catus) and their main mammalian prey species (i.e., Rodentia and Lagomorpha). In 23,373 trap nights, we totaled 21,729 independent records of our focal species. Our results show tendencies toward nocturnality at high land-use intensification, with potential impacts on species fitness. Nocturnal mesocarnivores decreased their diurnal/crepuscular activity, while cathemeral activity shifted to nocturnal activity at high land-use intensification, but only when in sympatry with a competitor. High land-use intensification decreased the activity overlap between native and domestic mesocarnivores but increased the overlap between native mesocarnivores. High intensification also reduced overlap with prey species. Notably, foxes displayed peaks of activity opposing those of dogs, and plasticity in activity pattern when in sympatry with dogs, such as strategies to avoid encounters. We stress the need to suppress the free-roaming and unsupervised activity of dogs to mitigate impacts of high land-use intensification on mesocarnivores.
- ItemRufous-legged Owl (Strix rufipes) and Austral Pygmy Owl (Glaucidium nanum) stand use in a gradient of disrupted and old growth Andean temperate forests, Chile(TAYLOR & FRANCIS LTD, 2012) Ibarra Eliessetch, José Tomás; Galvez, Nicolas; Gimona, Alessandro; Altamirano, Tomas A.; Rojas, Isabel; Hester, Alison; Laker, Jerry; Bonacic, CristianWe studied how human induced structural changes in forests affect stand use of the Rufous-legged Owl (forest-specialist) and the Austral Pygmy Owl (forest-facultative), in a gradient from lowland disrupted forests to protected Andean forests in Chile. We also tested if the calls of one species influenced the calling behaviour of the other. We detected a total of 34 Rufous-legged Owls and 21 Austral Pygmy Owls during the four seasons. Rufous-legged Owls were found principally in old growth Araucaria-Nothofagus stands (32.4%), and Pygmy Owls in old growth evergreen stands (52.4%). For both species there was a seasonal effect on call response, with a drop in responses in autumn and winter. Our models suggested that Rufous-legged Owls inhabit a more specific range of habitat characteristics than Pygmy Owls. The former selected stands with tall trees, relatively low tree density, and high bamboo density. Pygmy Owls selected stands with tall trees and relatively high tree density. There was no evidence that either species influenced the calling behaviour of the other, suggesting no negative association between use of a territory by the two species. Our results emphasize the importance of structural components of old growth forests for both species, but also the relevance of stands surrounding protected areas.
- ItemStraight from the Guin & SIM;as mouth: Diet of a Neotropical carnivore documented through camera traps(2023) Palomo-Munoz, Gabriela; Galvez, Nicolas; Alarcon, Valentina; Minte, Eduardo; Gallardo, Belen; Kramer, ThomasPredators are known to carry prey in their mouth for many purposes, including providing for dependent young or caching. Studying predator diet through the use of remote camera traps has seldom been explored, aside from natural history observations. We provide photographic evidence of prey carrying behavior of the elusive guin & SIM;as (Leopardus guigna) in two study sites in a temperate rainforest of Chilean Patagonia. We recorded 35 photographs and 12 events of guin & SIM;as carrying prey using camera traps across 57 sites between 2019 and 2022. All photographs show a rodent as prey except in one, where based on morphology, we conclude that it is a colocolo opossum, locally known as 'Monito del Monte' (Dromiciops gliroides). All events happened between 2000 and 0800 h, consistent with previous research documenting diel patterns of guin & SIM;as in Chile. We argue that camera traps may offer an alternative to help us understand the feeding ecology and diet, especially when collecting scat becomes difficult (e.g., rugged terrain, sites with heavy rainfall). This work discusses the use of camera traps to study predation events and predator diets. The observations here broaden our understanding of guin & SIM;a predatorprey interactions and can help generate new ways to study diet.