Risk effects cascade up to an obligate scavenger

Area of Science:

• Ecology
• Behavioral Ecology
• Wildlife Conservation

Background:

• Predation risk significantly impacts prey populations, but its effects on scavengers are less understood.
• Obligate scavengers, like Andean condors, face heightened vulnerability while foraging on carrion, often shared with apex predators.
• Understanding how scavengers perceive and respond to risk is vital for conservation efforts.

Purpose of the Study:

• To investigate how predation risk influences the foraging behavior of Andean condors (Vultur gryphus).
• To determine if condors adjust their habitat selection and carrion exploitation strategies in response to puma (Puma concolor) predation risk.
• To explore the role of landscape features in mediating risk for obligate scavengers.

Main Methods:

• Satellite telemetry tracked nine Andean condors to analyze flight paths and habitat selection.
• Camera traps monitored 41 natural carcasses and 25 experimental carrion stations to observe foraging behavior.
• Habitat variables, including vegetation height and slope, were analyzed in relation to condor presence and puma kill sites.

Main Results:

• Condors actively searched for carrion in areas with a high likelihood of puma kills.
• Condors avoided exploiting carrion located in areas with tall vegetation and steep slopes, which are preferred puma stalking habitats.
• Risk management by condors appeared to occur primarily through pre-landing site assessment, prioritizing safe foraging locations.

Conclusions:

• Andean condors exhibit sophisticated risk-assessment behaviors, avoiding foraging sites associated with potential puma threats.
• This study highlights that predation risk effects extend beyond direct predator-prey interactions, significantly impacting obligate scavengers.
• Conservation strategies for Andean condors should consider the landscape's risk structure and the availability of safe foraging opportunities.