Vegetated microhabitats are critical for avian access to arid zone waterholes

Project: HDR ProjectPhD

Description

Long lasting waterholes provide resources and habitats that are essential for the persistence of many avian species in arid landscapes, especially in hot and dry periods when water demand is high. As air temperatures rise under climate change, pressure on waterhole access for smaller subordinate species is likely to increase as larger predatory birds begin to frequent waterholes more often to hunt. We investigated if vegetated microhabitats facilitate surface water access for terrestrial avian species during periods of high surface water demand when predation risk is high. Camera trap data were collected at six long lasting waterhole sites in West MacDonnell and Watarrka National Parks across three sampling seasons throughout 2018 and 2019. Recorded species were assigned to functional groups, including nectarivores, granivores, carnivores, omnivores and insectivores. Similarities between functional group daily trapping rates (DTRs) (collected by the cameras) and microhabitat variables (determined a priori) were analysed using non-metric multidimensional scaling (NMDS). Nectarivores, small omnivores and small granivores showed significant positive relationships with distance (decreasing) to nearest shrub and percent cover variables. Large granivores, large omnivores, carnivores and insectivores showed no significant relationships with habitat variables collected during the study. With the number of days exceeding 35°C likely to increase under predicted climate change scenarios it is probable that periods of high avian water demand and predation risk will increase in the future. Our results suggest waterholes surrounded by vegetative cover provide subordinate avian species with refuge from predators and increase opportunities to safely access the water during these times.
StatusActive
Effective start/end date1/02/17 → …