An Indonesian bird first observed 15 years ago is a species previously unknown to science, a new study confirms.

An elusive bird, spotted on the island of Sulawesi (map) in 1997, now has an official name: the Sulawesi streaked flycatcher (Muscicapa sodhii).

Ben King, a bird-watching guide, and his clients were the first to notice the bird, which had a distinctive streaked throat and looked smaller than a related species, the gray-streaked flycatcher (M. griseisticta). (See photo: "New Bird Found in Indonesia.")

Several years later, that sighting inspired bird expert Frank Rheindt of the National University of Singapore and colleagues to travel to Sulawesi in 2011 and 2012 to search for the enigmatic animal.

But the bird's unassuming, high-canopy lifestyle made it tough to find, and the team didn't spot a specimen until 2012, according to the study, published November 24 in the journal PLOS ONE.

"After traveling to an area where it had previously been reported, it took many days of dedicated searching to find one in the first place," said study co-author Rheindt.

Co-author Pamela Rasmussen of Michigan State University, in East Lansing, received funding for the expedition from the National Geographic Society's Committee for Research and Exploration.

Bird of a Different Feather

Careful examination of birds brought to the study team by local hunters revealed the Sulawesi streaked flycatcher differs from other flycatchers in its feathers, body structure, song, and genetic makeup.

The new species is distinguished by its mottled throat markings, strongly hooked bill, and shorter wings and tail. Its song is similar to that of other Asian flycatchers, with whistles, chirps, and trills, but it is slightly higher pitched. (See an interactive map of birds threatened around the world.)

While its plumage is most similar to that of the gray-streaked flycatcher, genetic analysis revealed the Sulawesi streaked flycatcher is more closely related to the Asian brown flycatcher (M. dauurica siamensis).

The new species also appears to be widespread, likely because it does not need pristine forest to survive and can tolerate living in habitats disturbed by human activity.

These factors suggest the species is not currently threatened with extinction, but the researchers emphasize that this could change with increasing deforestation on the island. (See "The 1,300 Bird Species Facing Extinction Signal Threats to Human Health.")

"How Little We Know"

In addition to the flycatcher, several new bird species have been discovered in Sulawesi, a global hot spot for avians. The island is home to at least 42 species found nowhere else on Earth.

Despite its abundance of native species, the birds of Sulawesi are relatively unknown. Approximately 98 percent of the world's birds have been described. (See National Geographic's backyard bird identifier.)

"Birds are the most well-known animal class on earth, so the fact that a novel bird species can still be found on the well-explored island of Sulawesi in the 21st century," Rheindt said, "demonstrates how little we actually know about our planet."