Three decades of wildlife radio telemetry in India: A review

Abstract

From 1983, there have been three decades of the application and development of radio telemetry for wildlife studies in India. In this article, we review 82 studies from India, covering 47 species from four taxonomic classes. We examine and discuss the trends in the selection of study species, habitats and objectives of radio-telemetry studies and the functional success of radio collars and tags. A strong bias for study species and study region is observed and researchers generally tend not to look beyond the traditional research questions. Habitats that are difficult to access, such as the Trans-Himalayas, the Himalayas and north-eastern India, are overlooked. Most of the studies aimed to infer primary information only, such as home range, migration and movement patterns and habitat preference (53.7%, 47.6% and 28.1% studies, respectively). We expect these trends to change with time as the development of technology allows researchers to explore further. We investigated the tracking histories of 483 animals and the records of 496 radio collars or tags, but detailed information could be acquired for only 330 collars or tags. Of the collars, 49% malfunctioned before the end of their anticipated life due to a variety of reasons, early battery drainage being the prevalent cause. The performance of different technologies and collar manufacturers was also analysed but the small sample size was an issue for most of the cases. Argos-based collars and tags generally failed to record most of the locations precisely and failed to transmit them successfully. Issues with permissions and capturing animals for tagging, particular to India, are also discussed. A uniform and centralized system for granting permissions and guidelines for capturing and handling animals would be beneficial to future telemetry studies.