The Giant Hummingbird of western South America has been discovered to actually be two separate species by an international group of researchers. The northern population of these birds remains in the high Andes year-round, while the southern population migrates from sea level up to 14,000 feet for the nonbreeding months. Despite appearing identical, their genomes and behaviors tell a different story. This discovery was published in the Proceedings of the National Academy of Sciences and sheds light on the unique characteristics of these birds.
Lead author Jessie Williamson describes the Giant Hummingbirds as amazing birds, about eight times the size of a Ruby-throated Hummingbird. The genomes of the two populations were sequenced, revealing their significant differences. Senior author Chris Witt compares the distinction between the two species to that of chimpanzees and bonobos, highlighting their long-standing separation. The mystery of the Giant Hummingbirds has baffled researchers until now, with the two species existing in isolation for millions of years.
The researchers initially set out to track the migratory patterns of the Giant Hummingbirds and were surprised to find that some individuals traveled up to 5,200 miles from the Chilean coast to the Andes of Peru and back. This migration is considered one of the longest in the world for hummingbirds. The shift in migratory behavior played a crucial role in driving the speciation of these birds, although it remains uncertain whether one species gained migratory behavior or the other lost it.
The proposed common names for the two species are the Northern Giant Hummingbird and Southern Giant Hummingbird. The southern migrant species will retain the Latin name Patagona gigas, while the resident northern population is suggested to be named Patagona chaski, with “chaski” meaning “messenger” in Quechua. The researchers relied on support and local knowledge from landowners and villages in Peru and Chile for their fieldwork, with some challenges faced in capturing Giant Hummingbirds due to their observant nature.
Currently, the populations of Giant Hummingbirds, both north and south, are stable and common within their ranges. Some individuals even visit backyard nectar feeders. The researchers plan to continue studying these enigmatic birds to understand how the two species interact, compete for resources, and coexist within their winter ranges. They are particularly interested in learning more about the dramatic shifts in elevation during migration by the Southern Giant Hummingbirds and how they physiologically adapt to these movements like miniature mountain climbers.