Hummingbirds Fitted with Tiny Backpacks for Research
Hummingbirds Fitted with Tiny Backpacks for Research
A hummingbird loaded with a backpack-like “tracker” that provides detailed data on its movements in the high-altitude Andes.
Alyssa Sargent, a doctoral student in biology at the University of Washington, is pushing the boundaries of hummingbird tracking with innovative technology. Her work, which blends wildlife biology with mechanical engineering principles, offers a fascinating glimpse into the lives of these tiny, high-speed birds.
“My expertise largely lies in what I would call onboard devices,” shared Sargent. “That’s a fancy way of saying something that you actually put onto the animal itself in order to learn more about them."
Sargent’s journey into the world of hummingbird tracking began with a fascination for these unique creatures and their conservation.
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A great sapphirewing hummingbird, or Pterophanes cyanopterus. Photo: Pedro Arturo Camargo-Martínez
“They can fly backward and upside down and are the only birds that can truly hover. They come in every color you can imagine and have crazy names like ‘Sunangel’ and ‘Mango,’” she said.
This passion, combined with her experience in field ecology, led her to explore how technology could unlock previously inaccessible insights into hummingbird behavior. Traditional methods of studying birds, which often involve manual tracking and observation, can be inefficient and disruptive.
“We were literally on the ground, trying to see where the bird is nesting,” Sargent said, recalling her experiences in Australia studying fairywrens. “So we’re running around after the bird with our binoculars, and it’s a lot of fun, but it's also not the most efficient way to work with wildlife and can be very disruptive to the habitat."
It is critical to understand the behavior of these small wildlife – including how they mate, compete, and interact – because they often signal distress in a habitat due to their vulnerability. Even the slightest changes in air pressure and temperature can impact these species. But many questions remain, such as how roads and agricultural spaces affect their flight patterns.
“Some work has shown that hummingbirds will avoid spaces that are agricultural, and they’ll preferentially fly through forested areas even if it means they have to fly a lot farther,” Sargent shared.
To further study these behaviors, Sargent leveraged two kinds of wildlife trackers, which she calls “backpacks” because they are harnessed around each wing and sit on the back.
"The backpack is a means to an end. It’s a way to attach the tag more than anything else," she clarified. These backpacks can accommodate various devices, including radio tracking tags and accelerometers. “You can swap out the device on it to study different metrics.”
The research team's tracking system setup. Photo: Alyssa Sargent
The current study utilized a radio tracking device from Cellular Tracking Technologies called ‘LifeTag,’ which is a tiny solar-powered tag specifically designed for small wildlife. The tag emits a radio frequency that pings off several receivers, which are installed across a landscape in a grid formation. When the receiver gets the signal, they are able to triangulate the bird’s position. But the data is not exact.
The tradeoffs of using a solar-powered tag, which requires sunlight to operate, versus a battery-powered tag are not ideal because hummingbirds often live in very dense and complex ecosystems. “It’s like tracking a needle in a haystack,” Sargent said. “Except that needle is moving up to 30 miles per hour.”
Solar-powered tags can deliver data for years, but battery-powered tags are only available for fleeting periods. But, as Sargent explains, the technology they used is already obsolete. Newer, smaller tags, like the “BlūMorpho” and the “BlūBat” from Cellular Tracking Technologies, offer significant improvements in size and battery life. The BlūMorpho tag only weighs 60 milligrams, a dramatic reduction from previous models. These advancements will allow researchers to track smaller hummingbird species and gather more detailed information about their daily lives.
“The main priority is to not harm the animals,” she said. “We always say that ‘the birds come first’, and all the work we do goes through extensive ethical verification.”
While radio tracking has proven valuable, Sargent believes GPS technology holds the key to the future of hummingbird tracking because of its accuracy. However, current GPS tags are too large for most hummingbird species. Miniaturizing GPS tags to a size suitable for hummingbirds would revolutionize the field, providing unprecedented accuracy in tracking these elusive birds.
Sargent's work highlights the crucial role of mechanical engineering in advancing our understanding of the natural world. By developing innovative tracking technologies, engineers are empowering ecologists like Sargent to unlock the secrets of hummingbird behavior and contribute to their conservation.
“We must care about what a little hummingbird is doing,” she said. “Imagine trying to conserve an animal when you have no idea what habitat it’s using, or how far it’s moving every day, or where it's ending up every night. These are important basic life history questions that we must answer to effectively conserve an animal.”
Cassandra Kelly is a technology writer in Columbus, Ohio.
“My expertise largely lies in what I would call onboard devices,” shared Sargent. “That’s a fancy way of saying something that you actually put onto the animal itself in order to learn more about them."
Sargent’s journey into the world of hummingbird tracking began with a fascination for these unique creatures and their conservation.
A great sapphirewing hummingbird, or Pterophanes cyanopterus. Photo: Pedro Arturo Camargo-Martínez
This passion, combined with her experience in field ecology, led her to explore how technology could unlock previously inaccessible insights into hummingbird behavior. Traditional methods of studying birds, which often involve manual tracking and observation, can be inefficient and disruptive.
“We were literally on the ground, trying to see where the bird is nesting,” Sargent said, recalling her experiences in Australia studying fairywrens. “So we’re running around after the bird with our binoculars, and it’s a lot of fun, but it's also not the most efficient way to work with wildlife and can be very disruptive to the habitat."
It is critical to understand the behavior of these small wildlife – including how they mate, compete, and interact – because they often signal distress in a habitat due to their vulnerability. Even the slightest changes in air pressure and temperature can impact these species. But many questions remain, such as how roads and agricultural spaces affect their flight patterns.
“Some work has shown that hummingbirds will avoid spaces that are agricultural, and they’ll preferentially fly through forested areas even if it means they have to fly a lot farther,” Sargent shared.
To further study these behaviors, Sargent leveraged two kinds of wildlife trackers, which she calls “backpacks” because they are harnessed around each wing and sit on the back.
"The backpack is a means to an end. It’s a way to attach the tag more than anything else," she clarified. These backpacks can accommodate various devices, including radio tracking tags and accelerometers. “You can swap out the device on it to study different metrics.”
The research team's tracking system setup. Photo: Alyssa Sargent
The tradeoffs of using a solar-powered tag, which requires sunlight to operate, versus a battery-powered tag are not ideal because hummingbirds often live in very dense and complex ecosystems. “It’s like tracking a needle in a haystack,” Sargent said. “Except that needle is moving up to 30 miles per hour.”
Solar-powered tags can deliver data for years, but battery-powered tags are only available for fleeting periods. But, as Sargent explains, the technology they used is already obsolete. Newer, smaller tags, like the “BlūMorpho” and the “BlūBat” from Cellular Tracking Technologies, offer significant improvements in size and battery life. The BlūMorpho tag only weighs 60 milligrams, a dramatic reduction from previous models. These advancements will allow researchers to track smaller hummingbird species and gather more detailed information about their daily lives.
“The main priority is to not harm the animals,” she said. “We always say that ‘the birds come first’, and all the work we do goes through extensive ethical verification.”
While radio tracking has proven valuable, Sargent believes GPS technology holds the key to the future of hummingbird tracking because of its accuracy. However, current GPS tags are too large for most hummingbird species. Miniaturizing GPS tags to a size suitable for hummingbirds would revolutionize the field, providing unprecedented accuracy in tracking these elusive birds.
Sargent's work highlights the crucial role of mechanical engineering in advancing our understanding of the natural world. By developing innovative tracking technologies, engineers are empowering ecologists like Sargent to unlock the secrets of hummingbird behavior and contribute to their conservation.
“We must care about what a little hummingbird is doing,” she said. “Imagine trying to conserve an animal when you have no idea what habitat it’s using, or how far it’s moving every day, or where it's ending up every night. These are important basic life history questions that we must answer to effectively conserve an animal.”
Cassandra Kelly is a technology writer in Columbus, Ohio.
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