Carnivores 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 Araucanía 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 güiña 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.

1. Land 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.2. 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 cooccurrence of native and domestic mesocarnivores led to alterations in species' temporal activity.3. 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. 4. 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 | 2963

Wildfire regimes are being altered in ecosystems worldwide. The density of reptiles responds to fires and changes to habitat structure. Some of the most vulnerable ecosystems to human-increased fire frequency are old-growth Araucaria araucana forests of the southern Andes. We investigated the effects of wildfires on the density and richness of a lizard community in these ecosystems, considering fire frequency and elapsed time since last fire. During the 2018/2019 southern summer season, we conducted 71 distance sampling transects to detect lizards in Araucaria forests of Chile in four fire “treatments”: (1) unburned control, (2) long-term recovery, (3) short-term recovery, and (4) burned twice. We detected 713 lizards from 7 species. We found that the density and richness of lizards are impacted by wildfire frequency and time of recovery, mediated by the modification of habitat structure. The lizard community varied from a dominant arboreal species (L. pictus) in unburned and long-recovered stands, to a combination of ground-dwelling species (L. lemniscatus and L. araucaniensis) in areas affected by two fires. Araucaria forests provided key habitat features to forest reptiles after fires, but the persistence of these old-growth forests and associated biodiversity may be threatened given the increase in fire frequency.

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