Effects of human impacts on habitat use, activity patterns and ecological relationships among medium and small felids of the Atlantic Forest

Abstract

Competition theory and niche theory suggest that two morphologically similar species may coexist by reducing the overlap of at least one dimension of their ecological niche. The medium and small Neotropical felids are an interesting group of carnivore species for studying intraguild competition. Due to differences in size it is expected that the larger ocelot exert strong interference competition on the smaller felids (southern tiger cat, margay and jaguarundi); which, in turn, may exert exploitative competition among themselves. Moreover, landscape changes due to human activities may alter these interspecific interactions. We studied the habitat use and the spatial and temporal interspecific relations of the medium and small Atlantic Forest felids, in a landscape with different levels of anthropogenic impact. We estimated the detection probability, and occupancy probability of these cats and whether these parameters are affected by environmental and anthropogenic variables or by the estimated occupancy and detection probability of the ocelot. We estimated the overlap in daily activity patterns between pairs of the four species and changes in their activity in response to anthropogenic impact. We also studied the potential changes that may have occurred in the daily activity of the small felids in relation to ocelot's occupancy probability. The probability of habitat use of the small- and medium-size felids was negatively associated to the intensity of landscape use by humans. Co-occurrence models indicated that the probability of habitat use by southern tiger cats decreased with ocelot occupancy probability. This effect was higher as human disturbance increased. Moreover, the ocelot and the southern tiger cat became more nocturnal in sites with higher human access, suggesting that they may be temporally avoiding encounters with humans or dogs. Conservation of medium and small felids in the Atlantic Forest depends not only on the establishment and implementations of protected areas but also on the management of human's land uses.

Cats under cover: Habitat models indicate a high dependency on woodlands by Atlantic Forest felids

“…Local‐scale studies of habitat use show that these four felids avoid areas with high human impact, but the three smaller ones use human‐modified areas more frequently than do ocelots (Di Bitetti, De Angelo, Di Blanco & Paviolo, ; Kasper, Schneider & Oliveira, ; Rinaldi, Rodriguez, Carvalho & Passos, ). The last pattern could result from interference competition exerted by the ocelot on the smaller felids (the “pardalis” effect; de Oliveira et al., ; Cruz et al., ), whereby ocelots may occur in better conserved areas while the small felids are restricted totally or partially to suboptimal habitats (de Oliveira & Pereira, ; de Oliveira et al., ; Di Bitetti et al., ). In the Atlantic Forest of Argentina, the probability of habitat use by ocelots is negatively affected by habitat changes and anthropic pressures and the probability of habitat use by southern tiger cats is negatively affected by ocelot occupancy probability (Cruz et al., ).…”

Feline predator–prey relationships in a semi‐arid biome in Brazil

“…This is consistent with an observation known as 'ocelot effect', where ocelots may have a negative impact on smaller sympatric felids due to the potential for intraguild predation, which may be reflected in an altered distribution of the smaller felids (Oliveira et al, 2010). However, we believe that the spatial segregation of the northern tiger cat and ocelot will only arise in more extensive areas of well-preserved habitat, such as that found in our study area and the mosaic of protected areas surveyed in Argentina (Di Bitetti et al 2010, Cruz et al, 2018. On the contrary, where the landscape was characterized by small and isolated fragments of forest, the northern tiger cat did not segregate spatially from ocelots, but became more active during the day (Massara et al, 2016).…”

“…However, we believe that the spatial segregation of the northern tiger cat and ocelot will only arise in more extensive areas of well‐preserved habitat, such as that found in our study area and the mosaic of protected areas surveyed in Argentina (Di Bitetti et al . , Cruz et al ., ). On the contrary, where the landscape was characterized by small and isolated fragments of forest, the northern tiger cat did not segregate spatially from ocelots, but became more active during the day (Massara et al ., ).…”

“…The presence of one species may interfere with the occurrence of the other, with the subordinate species being obliged to occupy structurally less complex habitats (Palomares & Caro, 1999). Evidence of a process of this type has been found in forested ecosystems in Argentina, where northern tiger cats were more abundant in less well-preserved areas, thus avoiding competition with the ocelot (Di Bitetti et al, 2010, Cruz et al, 2018. A similar situation may be occurring in our study area, where the ocelot occupies habitats with denser vegetation in comparison with the northern tiger cat, which may be restricted to areas of shrub caatinga.…”

Coexistencia de Vulpes macrotis y Canis latrans (Carnivora: Canidae) en la Reserva de la Biosfera de Mapimí, México

“…Para los modelos de ocupación, un sitio se definió como cada estación de cámara-trampa, sin embargo, dado que el campo de muestreo en la cámara solo representa un punto en el espacio geográfico del sitio, más no un área, la ocupación (Ψ) se interpretó como la probabilidad de uso del sitio (Cruz et al, 2018;Farris et al, 2016;MacKenzie et al, 2018). Así mismo, las historias de captura se analizaron agrupadas en 3 días seguidos de fototrampeo.…”