Data for: Evaluating the effects of fringing vegetation and predation risk at artificial water sites
Description
Recent literature suggests that many terrestrial birds in arid environments will become increasingly reliant on surface water from sources such as waterholes as air temperatures increase with a warming climate. To do this however, they must often transition away from their preferred foraging habitat and, in doing so, expose themselves to predation. We conducted two field experiments at the Alice Springs Desert Park to test whether the presence of vegetative cover and predation risk affected terrestrial bird visits to experimental water sites placed in the landscape. We predicted that small and intermediate-sized canopy-foraging birds would spend a significantly greater amount of time at vegetated water sites than those in the open, even when perceived predation risk was high. Linear mixed effects models were used to test differences in the mean amount of time per day (seconds) birds spent at vegetated and open sites in each experiment. The presence of a decoy predator did not affect the amount of time birds spent at either vegetated or open sites. This result was likely due to the stationary nature of the decoy predator model used in the predation experiment. Vegetated sites, irrespective of decoy predators, had a significant positive effect on the Western Bowerbird (intermediate canopy forager), while open sites had a significant positive effect on the Zebra Finch (small ground forager). These results show that the habitat various birds have adapted to exploit while foraging for food items, along with other behavioural traits (e.g. flocking behaviour), strongly influences where they will attempt to access surface water when transitioning away from food items. While predation pressure has previously been shown to affect avian decision making when accessing food resources, further investigation is required to determine if predation risks influence prey species attempting to access water sites.