A novel digital telemetry system for tracking wild animals: A field test for studying mate choice in a lekking tropical bird

摘要

1. Radiotelemetry provides a tool for monitoring animals that are difficult to observe directly. Recent technical advances have given rise to new systems that present expanded opportunities for field research. We report the results of the first field test of Encounternet, a new digital radiotelemetry system comprising portable receiver stations and digital tags designed for long-term studies of the social behaviour and ecology of free-living animals. 2. We present results from a series of field tests designed to evaluate the utility of Encounternet for monitoring animals in a neotropical forest, with an emphasis on evaluating mate sampling behaviour in female long-tailed manakins. In this tropical species, females visit leks where males perform elaborate dances on horizontal perches. Females are highly cryptic in both plumage and activities, and therefore, Encounternet might provide unique insights into female behaviour and ecology. 3. Our first two tests revealed that pulse strength and probability of detection decrease with the distance between tag and receiver and that tags placed on a fixed perch near a receiver showed different patterns of reception than more distant tags. Our third test revealed that antenna angle had only a small influence on pulse strength. 4. Blind analysis of simulated bird movements confirmed that the Encounternet system provides reliable information on animal activity. Data from multiple receivers permitted accurate reconstruction of simulated bird movements. Tag detections showed low levels of false negatives and false positives. 5. Female manakins responded well to carrying Encounternet tags attached by an elastic leg harness. Birds flew well upon release and were detected for 7.5 ± 0.8 days after release. Recaptures and re-sightings of females were rare in our large study population, yet there were two occasions where we confirmed that the tag fell off within 1 year. 6. We conclude that Encounternet technology provides an effective tool for monitoring animal ecology and behaviour. We show that it is capable of providing accurate measures of distance and that it is a highly versatile system for studying the ecology and behaviour of free-living animals. We discuss the unique opportunities facilitated by this technology for future ecological and behavioural studies. © 2012 The Authors. Methods in Ecology and Evolution, © 2012 British Ecological Society.