Home range and presence of the California Condor <i>Gymnogyps californianus</i> in a protected area in Baja California: seasonal, biological, and food supplementation influences

Summary Obligate avian scavengers, such as the “Critically Endangered” California Condor Gymnogyps californianus , face significant threats from human activities and environmental changes. This study examines the home range and presence of reintroduced California Condors in a protected area in Baja California, Mexico, focusing on the influences of seasonality, biological factors, and food supplementation. Using spatial data collected over 12 months with telemetry equipment, we analysed condor movements within and beyond the boundaries of the Parque Nacional Sierra de San Pedro Mártir. Our findings reveal that condors spend over half their time within the protected area, with an increased presence during winter months. Supplementary feeding programmes significantly increased condor presence within the park, particularly in spring and summer. Home range analyses showed that season significantly influenced home range sizes, with smaller ranges observed during winter compared with other seasons. Additionally, male condors had larger home ranges than females during spring, but no significant sex differences were observed in other seasons. Age did not have a significant effect on home range size. This study emphasises the importance of protected areas and supplementary feeding programmes in condor conservation, highlighting the necessity of continuous monitoring and management to help support this iconic species.