Researchers attached tiny “backpack” trackers to hummingbirds in the Colombian Andes to learn more about their movements.
As they report in a paper in the journal Ecology and Evolution, the tracking system will aid conservation efforts in this region by revealing the previously hidden movements of hummingbirds and other small animals.
For the project, researchers teamed up with scientists at the Pontificia Universidad Javeriana in Colombia and officials at Chingaza National Natural Park. The team hopes that data on small animals’ movements will inform plans to expand the park and connect it to other nearby protected areas.
Previously, it was impossible to collect movement data for hummingbirds and other small animals in the region. The team set up an automated radio telemetry grid in the páramo, a high-altitude region in the Andes more than 10,000 feet above sea level.
Their technology generates fine-scale resolution and continuous location estimates for individual animals, collecting in millions of data points that provide information on species’ habitat requirements, movement patterns, and seasonal occurrence, all of which are critical for developing landscape-level management practices and avoiding local extinctions.
“Hummingbirds might not get the same buzz that bees do when it comes to the ecosystem services they provide, but they’re hugely important pollinators all the same,” says coauthor Alyssa Sargent, a University of Washington doctoral student in biology.
“If you think about it in practice, it’s very challenging to protect an animal when you don’t know where or how far it moves each day, or what kinds of habitats it prefers. The fact that these questions are still largely unanswered when it comes to hummingbirds means that there remains a lot of important work to be done!”
The researchers used backpack-like harnesses to attach tiny transmitters to the hummingbirds. Since the birds themselves weigh at most about 10 grams, which is almost as heavy as an Oreo cookie, the transmitters had to be incredibly light—less than 500 milligrams, or the weight of a Tic Tac. The transmitter included a solar panel, providing it power for the bird’s lifetime.
In early 2023, the researchers placed tags on 10 adult hummingbirds from two species, Great Sapphirewing and Bronze-tailed Thornbills, and followed the birds’ movements for up to 100 days.
“Through this, we have been able to obtain information on foraging routines, home ranges, and seasonality,” says lead author Cristina Rueda Uribe, a graduate student at the University of Aberdeen.
“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 study is the first to use automated radio signals in a high-mountain ecosystem to track the movements of animals, according to Rueda Uribe. It is also one of only a handful to try to track animal movements across terrain difficult for humans to trek across. The team plans to compare its findings about high-altitude hummingbird movements to data already collected by the team at the Colibrí Gorriazul Research Center, a separate mid-elevation site in the Andes.
The system prototyped in this study could easily be adapted to learn about small animals’ movements in other ecosystems, which directly impacts communities in the region.
“To know how to best conserve nature, we need to understand it fully, and this is opening the door to heretofore underexplored aspects of these small and elusive animals’ daily choices,” says co-senior author Alejandro Rico-Guevara, an assistant professor of biology and curator of ornithology at the UW Burke Museum of Natural History & Culture.
“This is especially important for the páramo biome, which maintains water sources for other ecosystems down the mountains and for humans as well. It is a tremendous biodiversity hotspot that is comparatively less studied and much more threatened because of climate change and human-driven shifts in land use.”
Additional coauthors on the study are from the Pontificia Universidad Javeriana, the Chingaza National Natural Park, Queen’s University Belfast, and the University of Aberdeen.
Funding for the research came from the UK Biotechnology and Biological Sciences Research Council, the UK Natural Environment Research Council, Walt Halperin Endowed Professorship at the UW, the UW Orians Award for Tropical Studies, the UW Margo and Tom Wyckoff Award, the National Science Foundation, the Rufford Foundation and the University of Aberdeen.
This story is adapted from a press release by the University of Aberdeen.
Source: University of Washington
