A newly identified songbird from the Babar Islands in Indonesia’s Banda Sea has been recognized as a distinct species due to its unique song, differentiating it from related species. Named the Merry Fantail (Lipidula laguceria), this bird was previously classified as identical to the Cinnamon Giant Fantail (Rhipidura fuscorufa), found approximately 135 km (84 mi) east of the Tanimbar Islands.
Rhipidura fuscorufa is a small insectivorous songbird belonging to the fantail family, Lingidae.
This species measures approximately 18 cm (7 inches) in length and is recognized for its cinnamon-hued tail and underparts, displaying the characteristic tail-spreading behavior typical of fantails.
Rhipidura fuscorufa was first described back in 1883 on the Tanimbar Islands.
Birds from Babar, located about 80 miles to the west, were once considered part of the same species. For over 120 years, this classification remained largely unchanged.
“Rhipidura fuscorufa is endemic to Indonesia, found on both Tanimbar Island and the Babar Islands,” elaborates Dr. James Eaton of Bird Tours Asia Limited and Dr. Alex Berryman of BirdLife International.
“It was initially described as a new species in 1883 based on specimens from the Tanimbar Islands.”
“Fifteen years later, specimens from Babar Island were also collected, but upon review in 1901, scientists maintained they were identical to those from Tanimbar.”
“For approximately 120 years, the prevailing taxonomic treatment in global and regional references classified Rhipidura fuscorufa as a monotypic species.”
Dr. Eaton identified differences between Babar and Tanimbar populations during a visit in 2011, suggesting the presence of an undescribed species based on distinct vocalizations.
To verify, the researchers examined 19 museum specimens held at the American Museum of Natural History in New York and the Tring Museum of Natural History in the UK, along with 18 audio recordings from the two island groups.
They observed subtle physical differences, noting that Babar birds generally have darker upper bodies and less extensive cinnamon-colored underparts compared to Tanimbar birds. No significant differences in wing, tail, beak, or leg measurements were found.
However, the songs revealed a different narrative.
“The vocalizations of Rhipidura fuscorufa populations vary significantly,” the researchers remarked.
“Babar bird calls typically consist of a series of single whistles that ascend in pitch, while Tanimbar bird calls combine short and long whistles to create a rhythmic pattern, often oscillating in pitch.”
“Although the strophe length of both populations is comparable, Tanimbar birds produce significantly more notes per strophe, with shorter intervals between notes.”
Cinnamon Giant Fantail (Rhipidura fuscorufa), November 2022. Image credit: James A. Eaton.
Over multiple years, scientists conducted 132 reproductive experiments during field visits to Tanimbar and Babar.
With remarkable consistency, birds from each island responded only to their own recordings, ignoring those from other island populations.
None of the Babar birds responded to Tanimbar songs, and vice versa, indicating a significant reproductive isolation.
“Despite both being categorized as monotypic, our data reveal discrete differences between Tanimbar and Babar populations of Rhipidura fuscorufa,” the researchers stated.
“Morphologically, the two populations exhibit subtle differences in plumage and are vocally distinct, with reproductive experiments suggesting that these vocal differences act as a barrier to mating.”
“On this basis, we propose that the Babar Islands’ population of Rhipidura fuscorufa deserves taxonomic recognition as a separate species: Lipidula laguceria.”
Both the newly described Lipidula laguceria and its relative, Rhipidura fuscorufa, are currently classified as Least Concern according to conservation standards, demonstrating adaptability in degraded and edge habitats over closed-canopy forests.
“Currently, Rhipidura fuscorufa is listed as Least Concern on the IUCN Red List,” the scientists remarked.
“Following their separation, both species’ ranges have narrowed, which may qualify them under IUCN criteria as threatened.”
“Nonetheless, both species are known to thrive in modified habitats abundant in clearings, edge areas, and even scrubland with tall mango trees, avoiding dense forests.”
“Thus, neither species fits the criteria for a threatened status and should continue to be classified as Least Concern.”
The discovery of Lipidula laguceria is detailed in a recent study published in the latest British Ornithologists Club Newsletter.
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James A. Eaton and Alex J. Berryman. 2026. A mysterious new species of fantail from Babar Islands, Maluku Province, Indonesia. British Ornithologists Club Newsletter 146 (2): 203-215; doi: 10.25226/bboc.v146i2.2026.a6
Source: www.sci.news