Scientists conducted an unprecedented expedition to three inaccessible islands in Indonesia and found 10 new species and subspecies of songbirds.
Written by: TIM Vernimmen
The Togian Jungle Flying Finch is a new bird subspecies discovered by scientists on Battudaka Island in the Togian Islands. Photo by JAMES EATON, BIRDTOUR ASIA
Many birds are brightly colored, active during the day, often chirping, and are easy to spot and identify. Over the past two decades, an average of fewer than six new species of birds have been found worldwide each year.
However, 2020 will be different, as scientists have just announced the discovery of 10 new bird species and subspecies in three Indonesian islands east of Sulawesi.
Frank Rheindt, an ornithologist at the National University of Singapore and head of the new study, said in 2013 and 2014, scientists spent six weeks collecting specimens of these amazing birds on the mountainous islands of Tagliabo, Perum and Batudaka, which are thought to be the hideouts of unknown birds. One reason for this is that 19th-century explorers didn't spend much time on the islands, such as the British naturalist Alfred Russel Wallace.
"We also want to visit those islands in the deep sea. Because those islands weren't connected to any other landmass during the Ice Age, they were a place of hope for discovering species that didn't exist elsewhere," said Rheindt, whose study was published this week in the journal Science.
Scientists are particularly concerned about the Taryaab Black Spotted Locust Warbler, whose habitat may have shrunk to several square kilometers due to wildfires and deforestation. Photo by JAMES EATON, BIRDTOUR ASIA
Many tropical forest birds avoid open areas, so "an ocean or even a road can stop them from migrating from one forest to another," he said. The few birds that happen to appear on isolated islands may spawn new species, such as those blown into the sea by storms.
Two of the newly discovered birds are willow warblers, a small insect-feeding songbird that spread across the Old World. Other birds include the Tagliabu Honey Bird, a honey-eating bird that feeds on many different species of nectar and fruits; and the Perren fantail pigeon, a bird that spreads its tail feathers when depressed or frightened.
Mochamad Indrawan, a field biologist at the University of Indonesia, was the first to discover and report on the Perlen fantail pigeon, but he was not involved in the new study.
"I really agree with the scientists' description of the new species, which is very useful. However, this is the era of extinction, the era of climate change, so I hope we can do more to protect these birds," said Indrawan, who has been working with communities on the island to protect their forests for nearly 30 years.
Different chirps
During the expedition, Rheindt and colleagues relied on a reliable method to track birds: calls. Scientists heard some birds chirping days before they discovered them.
Rheindt and his colleagues were on their first hike through the mountains of Taryab Island when they encountered heavy rain and considered returning. "All of a sudden I heard a typical insect-like cry, a black-spotted locust warbler I had never heard before," he recalled.
They had to climb a little further distance to find the little brown bird, which is now named the Taryabe Black Spotted Locust Warbler.
The team collected specimens of the birds and then returned to the lab to carefully describe their appearance and anatomy. The researchers also analyzed the birds' DNA and recorded chirps to confirm that the birds were indeed different from any known species and could be named new species or subspecies.
Nowhere to go
The birds are unlikely to live elsewhere and are therefore vulnerable to extinction, especially due to wildfires and deforestation, which has been rampant, the authors said.
Rheindt pays particular attention to the black-spotted locust warbler.
"We only found this bird in a small patch of dwarf vegetation on the mountain, where it is vulnerable to wildfires. As the temperature rises and the degree of drought increases, so does the risk of fire, and the bird has nowhere to go any higher. ”
Dewi Prawiradilaga, a biologist at the Indonesian Institute of Scientific Research, a collaborator in the study, added: "We must be optimistic that the new discoveries will help protect the safety of these birds and their habitats. ”
She hopes the Indonesian government will consider protecting the newly discovered species and subspecies.