Shy Cloud Forest Birds Identified as New Species

CAMBRIDGE, England, August 24, 2005 (ENS) - Two Colombian birds, from a family sometimes called the feathered mice of the forest, have been identified by their songs as species new to science. Logging in their cloud forest habitat is threatening the survival of both species.

The two new species are birds from the Cordillera Central mountains of Colombia - both of them in the Tapaculo family in the genus Scytalopus.

Unidentified tapaculos have been observed in the northern Cordillera Central for a decade, but it took an expert at bird identification who examined recordings of their songs to identify the new species.

Dr. Niels Krabbe, a research associate at the Zoological Museum, University of Copenhagen, Denmark, analyzed recordings made in the forest and found a new pattern that indicates a separate species that has been named Stiles’s Tapaculo, Scytalopus stilesi.

Danish ornithologist Dr. Niels Krabbe, is co-author of "Birds of Ecuador," which includes both photos and recorded sounds. (Photo courtesy Bird Songs International)

Further analysis of eight specimens taken in 2002 show the species is genetically distinct.

The species Stiles’s tapaculo is found throughout a 300 kilometer (200 mile) stretch of the Cordillera Central where it occupies cloud forests between 1,420 and 2,130 meters (4,650 and 6,988 feet) in altitude.

In this limited area it is a common understorey bird and is known from 21 localities, including several protected areas, according to BirdLife International based in Cambridge, England, which announced the discoveries today.

In an article in "The Auk," Dr. Krabbe and his team say the Stiles’s Tapaculo is found in continuous mature-forest remnants, large primary-forest fragments, riparian forests, and tall secondary-forest patches.

The team used a geographic information system (GIS) approach to model the potential distribution of the new species and assess its conservation status under the IUCN-World Conservation Union criteria.

"Scytalopus stilesi does not qualify as threatened according to those criteria, but it should be regarded as near threatened," Krabbe wrote. "The new species coexists with numerous threatened bird species that are in need of more effective conservation."

"The mid-elevation premontane wet forests to which the new species is restricted have been subject to severe deforestation and fragmentation," Krabbe and his team write.

The second new species is the Upper Magdalena tapaculo, S. rodriguezi. Its discovery is similar to Stiles’s tapaculo, since the presence of an unknown tapaculo in the Finca Merenberg mountains of the southern Cordillera Central has been known since the 1980s.

The Upper Magdalena tapaculo was identified by recordings of its distinctive call. (Photo by Paul Salaman courtesy BirdLife International)

"It was frustrating, waiting for years knowing there were new species to be discovered and protected," says Paul Salaman of Fundación ProAves, one of the expedition members who describes the Upper Magdalena tapaculo.

"Then we learned it was safe to visit the Finca Merenberg mountains and soon found the new species in dense understorey of primary forest. In appearance it’s very like other Scytalopus tapaculos, but has a distinctive voice," Salaman says.

The song is amongst the simplest of any Scytalopus, consisting of a single note repeated at a pace of four to five per second, usually given in strings of two to five phrases.

Currently the Upper Magdalena tapaculo is known from two localities on the east slope of the Cordillera Central at 2,000–2,300 meter elevation.

The species’ presumed area of occupancy is heavily deforested and its remaining suitable forest habitat may cover 169 square kilometers (65 square miles) or less.

One of the locations where the Upper Magdalena tapaculo is found, Merenberg Reserve, was Colombia’s first private protected area, although the site is known to be rapidly deteriorating through selective logging.

The authors have recommended the Upper Magdalena tapaculo be classified as Endangered.

Most tapaculos are dark colored and live in thick forest undergrowth, making them difficult to study in the field. They have subtle plumage variations, some of them age-related, although there is much individual variation, as well as differences between species.

Some taxonomists regard Scytalopus tapaculos as the most complicated of all Neotropical genera, BirdLife explains. Voice is the most important aid to their identification, and study of birds in the northern Andes has led to the description of three new species, and the elevation of several former subspecies to specific level in Ecuador.