INTRODUCTION: Since 2008 our teams have worked at 6 sites across Amazonia and adjacent habitats to track sandbank-dependent waterbirds, most notably the Orinoco Goose (Neochen jubata) and the Black Skimmer (Rynchops niger).
OBJECTIVES: To document intra-tropical migration strategies used by sandbank-dependent waterbirds in Amazonia; to understand stopover ecology and critical conservation implications in a context of high pressure for development including dams.
METHODS: We have used several technologies with varying degrees of success, including tracking with satellite transmitters, GSM collars, remotely downloaded antennae systems, and ICARUS tags that communicate with the International Space Station. RESULTS: Satellite tracking tag systems have outperformed other methods considerably in our remote fieldsites, so are ultimately worth the high purchase costs to deploy. New migration systems have been uncovered for both the Orinoco Goose and the Black Skimmer. High fidelity to both nesting grounds and certain stopover locations are observed in both species, offering opportunities to contribute to conservation needs. Orinoco Geese differ in their migration strategies regionally, likely as a result of cavity nest site limitation in more open savanna and grassland regions. They have a critical need for safe moulting grounds and are already adapting to many human-dominated landscapes including cattle production areas and ricefields, which may be altering their movement ecology in certain areas. Black Skimmers undertake long-distance migrations in which they may move considerable distances in both latitude and longitude. Individuals from the same breeding populations show highly variable strategies in where to spend the non-breeding season.
IMPLICATIONS: We consider the highly concentrated seasonal concentrations of Orinoco Goose in rice fields to be a potential concern for the conservation of this Near-Threatened bird, as persecution in rice fields is common for other waterbirds with which they associate, and disease transmission may be a growing risk. Global skimmer populations have declined in areas of dam construction, so we also discuss conservation concerns with the proposed the Bem Querer dam on the Rio Branco, Brazil to affect the integrity of this uniquely diverse river system, which we have recently observed to be an important north-south flyway for not only our target study species but also for many other species of waterbirds.
Animal Migration, waterbirds, Amazonia, movement ecology, Flood pulse ecology, rivers