Giants hummingbirds are not just one, but two species

A new study led by Cornell University has found that the giant hummingbird, previously thought to be a single species across western South America, is actually comprised of two distinct species.

The experts differentiated between the northern and southern populations of these hummingbirds, with the former residing year-round in the high Andes and the latter migrating from sea level up to 14,000 feet during non-breeding months. 

Significant differences in giant hummingbirds 

Despite their identical appearances, genetic and behavioral analyses indicate significant differences.

“They’re about eight times the size of a Ruby-throated Hummingbird,” said lead author Jessie Williamson, a postdoctoral fellow at Cornell. “We knew that some giant hummingbirds migrated, but until we sequenced genomes from the two populations, we had never realized just how different they are.”

Senior author Chris Witt, a biologist at the University of New Mexico, highlighted the extent of their difference: “They are as different from each other as chimpanzees are from bonobos. The two species do overlap on their high elevation wintering grounds.” 

“It’s mind-boggling that until now nobody figured out the giant hummingbird mystery, yet these two species have been separate for millions of years.”

Tracking the migratory paths of hummingbirds 

The discovery was initially part of a project to trace the migratory paths of the hummingbirds, using geolocators and satellite transmitters to track individual birds. 

Remarkably, the researchers documented one of the longest hummingbird migrations in the world, with birds traveling up to 5,200 miles from the Chilean coast to the Andes of Peru and back.

Speciation appears to have been driven by shifts in migratory behavior, though it is unclear whether this trait was gained or lost. 

Northern and southern giant hummingbird 

Previously, the giant hummingbird was the only recognized species on this branch of the hummingbird family tree, which contrasts sharply with its closest relatives that have diversified into 165 distinct species.

The researchers have proposed naming the two species the northern giant hummingbird and southern giant hummingbird, with the latter retaining the Latin name Patagona gigas and the former newly dubbed Patagona chaski, “chaski” being a Quechua word meaning “messenger.”

The study benefited significantly from the support and local knowledge of communities in Peru and Chile, particularly the village in Peru where co-author Emil Bautista resides. Capturing these birds for study proved to be exceptionally challenging due to their keen awareness and territorial behavior.

Despite these difficulties, both populations of the giant hummingbird are currently stable and are commonly seen within their ranges, sometimes even visiting backyard nectar feeders. 

Future research 

Going forward, the team plans to investigate the interactions between these two species, particularly in their shared wintering grounds.

“We have to figure out where these two forms come together and how they interact,” Witt said. “Do they compete, is one dominant over the other, how might they partition resources, and do they mix or spatially segregate within the winter range? Lots of interesting questions to pursue!”

“I’m really interested in how southern giant hummingbirds make such dramatic shifts in elevation during migration. They travel from sea level to the high Andes in just a few weeks. They’re like miniature mountain climbers. How do they change their physiology to facilitate these movements?” Williamson concluded.

More about giant hummingbirds 

Giant hummingbirds, known scientifically as Patagona gigas, hold the title of the largest member of the hummingbird family. They can reach a length of about 23 centimeters, making them considerably bigger than the more typically sized hummingbirds most are familiar with. 

Native to the Andes Mountains, they thrive in environments ranging from semi-desert to mountainous areas in countries like Peru, Chile, Bolivia, and Argentina.

Wing beats

These birds are distinct not only for their size but also for their relatively slow wing beats, especially when compared to their smaller counterparts who are known for their rapid flapping. 

Giant hummingbirds can beat their wings at a rate of about 12 to 15 times per second, which is leisurely by hummingbird standards. This wing beat allows them to hover effectively, a trait synonymous with hummingbirds, as they feed on nectar from a variety of flowers.

Body size

Their larger body size also impacts their feeding habits. Giant hummingbirds consume more nectar than the average hummingbird to sustain their energy levels. 

Moreover, they have adapted to a high-altitude environment, which affects the types of flowers they pollinate and their overall role in the ecosystem. 

Despite their size, they maintain the iridescent plumage characteristic of hummingbirds, although their colors might not be as vibrant as some of the more tropical species.

Ecological role

Giant hummingbirds also produce a distinctive, buzzing call that can be heard over long distances, a feature that makes them quite noticeable in their natural habitat. They play a crucial role in their ecosystems, pollinating plants that are adapted to their presence and size. 

Like all hummingbirds, they are vital for the health of their native habitats, contributing to the biodiversity that sustains these environments.

The study is published in the journal Proceedings of the National Academy of Sciences.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–