Otus brookii brookii, a subspecies of the Rajah scops-owl (Otus brookii) that had been lost to science since 1892, has been discovered alive and photographed in the montane forests of Mount Kinabalu in Borneo, Malaysia.
“It was a pretty rapid progression of emotions when I first saw the owl — absolute shock and excitement that we’d found this mythical bird, then pure anxiety that I had to document it as fast as I could,” said Dr. Andy Boyce, an ecologist in the Conservation Ecology Center at the Smithsonian Conservation Biology Institute and the Montana Cooperative Wildlife Research Unit at the University of Montana.
“Based on size, eye color and habitat, I knew it was the Bornean Rajah scops-owl.”
“What’s more, taking into account this bird’s specific plumage characters, known speciation patterns within the Otus genus and phylogeographic patterns of montane birds in Borneo and Sumatra, Otus brookii brookii is likely its own unique species and further study is needed.”
Dr. Boyce and colleagues rediscovered Otus brookii brookii in May 2016 in the montane forests of Mount Kinabalu on the island of Borneo at an elevation of 1,650 m.
The researchers also captured the first photographs of this subspecies in the wild.
“Unfortunately, we are only good at conserving what we know and what we name,” Dr. Boyce said.
“If this rare bird is endemic only to Borneo and is its own species, conservation action is more likely.”
“Our sole sighting during this intensive study confirms this owl lives in mature montane forests, likely above or below the survey area.”
“Those elevations are already threatened by habitat loss due to climate change, deforestation and palm oil development.”
“To protect this bird, we need a firm understanding of its habitat and ecology.”
Almost all data on the Rajah scops-owl is of the Sumatran subspecies. The vocalizations, distribution, breeding biology and population size of the Bornean subspecies are totally unknown.
Despite the lack of information on the species and subspecies, and the apparent rarity of the Bornean subspecies, the Rajah scops-owl was designated a species of Least Concern by the IUCN.
“Almost all basic elements of this species’ ecology remain unknown, including vocalizations, distribution, breeding biology, and population size,” the scientists said.
“Additionally, phylogeographic patterns of montane birds in Borneo and Sumatra, as well as plumage characters, suggest that Otus brookii brookii may be deserving of species classification.”
“However, the rarity of Otus brookii brookii has made quantitative phylogenetic analysis impossible.”
“Properly resolving the ecology, distribution, and taxonomic standing of Otus brookii brookii could have important conservation implications.”
The team’s paper was published in The Wilson Journal of Ornithology.
Emily Card et al. 2021. Rediscovery of Rajah Scops-Owl (Otus brookii brookii) on the island of Borneo. The Wilson Journal of Ornithology 132 (3): 769-773; doi: 10.1676/20-50