Tiny ‘bird backpacks’ being used to track hummingbird movement

By Elizabeth Hunter

Tiny solar-powered "bird backpacks" are being used to track hummingbirds in a unique new trial.

Researchers from the University of Aberdeen, the Pontificia Universidad Javeriana in Colombia, Queen’s University Belfast and the University of Washington in the United States, teamed up with the Chingaza National Park in Colombia to start the unique project.

To monitor the hummingbirds' movements, tiny trackers were attached to the birds' backs using a harness around their wings and chests like a tiny "bird backpack."

The tag monitors the hummingbirds' movements and locations through a signal-transmitting solar panel and has given researchers a unique insight into the birds' patterns.

Cristina Rueda Uribe, a PhD candidate from the University of Aberdeen's School of Biological Sciences, said: “We are very excited to have successfully implemented a system that is giving us a unique insight into the movements of hummingbirds and other small animals endemic to high mountain ecosystems of the Andes.

“The transmitters we attached to the hummingbirds are tiny!

"They weigh only 0.35g because the largest birds are only around 12-14g. We use a harness that goes around their wings and chest, so the tag sits on their back like a backpack.

"The tag has a solar panel and will transmit signals for the rest of their lifetime, whenever the sun is shining the panel is activated.

“Through this, we have been able to obtain information on foraging routines, home ranges and seasonality.

"This information increases our understanding about biodiversity in tropical mountains and is also useful to protect these species, as well as their key ecosystem roles as pollinators, in the face of ongoing climate and land use change."

The project aims to inform the park's plans to expand and connect to other nearby protected areas.

Previously, it has been impossible to collect movement data for hummingbirds and other small animals in the area, however, the team was able to set up an automated radio telemetry grid at 3,300m above sea level in the Andes of Colombia.

This technology generates fine resolution and continuous location estimates for individual animals, resulting in millions of data points that provide information on species’ habitat requirements, movement patterns and seasonal occurrence, all of which are important to inform landscape-level management practices that avoid local extinctions.

“Our system is the first to use automated radio signals to track movement in high mountain ecosystems of the Andes, and it is one of only a few that has been attempted in wild landscapes where terrain and vegetation are challenging," said Cristina.

"Its success is due to an huge international collaborative effort between scientists, designers, drone pilots, park rangers, and field ornithologists.

"This is such an important step forward as the system is mainly focused on tracking hummingbirds and revealing movement patterns that are key for their role as plant pollinators, in ecosystems that are especially vulnerable to changes in climate and land use.

“I am also excited that this project has motivated local management to use technology for conservation, and it has also inspired researchers to adapt this technology in other locations.

"We are now helping our collaborators to establish a similar grid in lowland forests in the Amazon region.”