Brett Smith for redOrbit.com – Your Universe Online
After years of study in a remote section of the Philippines, researchers can now confirm a victory for biodiversity, the discovery of two new owl species.
According to the current issue of Forktail, the yearly Journal of Asian Ornithology, the dual discovery was a huge payoff for the team of researchers that included Pam Rasmussen, a Michigan State University professor of zoology.
“More than 15 years ago, we realized that new subspecies of Ninox hawk-owls existed in the Philippines,” she said. “But it wasn´t until last year that we obtained enough recordings that we could confirm that they were not just subspecies, but two new species of owls.”
One of the new species, the Camiguin Hawk-owl, was found only on the small island of Camiguin Sur, which is located in the middle of the archipelago just north of the large Philippine island of Mindanao. Scientists have known about the owl for years, but simply thought it was a different form of an already existing species, Rasmussen said in a web video.
The new species is the only known owl to have blue-grey eyes and has a unique voice that is quite different than the owls of nearby Mindanao. The evening song of the Camiguin Hawk-owl contains a distinctive growling bass line. Zoologists have observed two of the owls communicating in short barking duets that start with a growl.
“We knew it was a distinct taxa,” Rasmussen added. “We didn´t realize it was at the species level.”
The second new discovery was also deemed unique because of its vocalizations. The Cebu Hawk-owl was thought to be extinct, due to deforestation that has ravaged the natural habitats of the island. It had also never been considered a distinct species. Like the Camiguin Hawk-owl, a study of the bird´s vocalizations mostly confirmed that it was a new species.
“The owls don’t learn their songs, which are genetically programmed in their DNA and are used to attract mates or defend their territory; so if they’re very different, they must be new species,” Rasmussen explained. “When we first heard the songs of both owls, we were amazed because they were so distinctly different that we realized they were new species.”
The research team that worked on the report included Rob Hutchinson from Birdtour Asia, who found the Camiguin owl when he received the group´s first batch of comprehensive audio recordings. The team also incorporated individuals from BirdLife International, the Oriental Bird Club, and the Philippines Biodiversity Conservation Foundation.
The description of new species by ornithologists has become quite rare, in fact Rasmussen and her team said they couldn’t remember the last time two were described in the same paper. The scientists said the owls likely avoided recognition as unique species for so long because the group displays multifaceted variations in appearance and both of their songs were unknown.
The birds´ remoteness also played a factor as both of their home islands are out of the way for ornithologists and birders, who typically invest their time in larger islands that host more species.
The Philippines can now add two more species to its staggering list of biodiversity. Conservation International considers the 7,000-island archipelago one of the world´s most biodiverse “hotspots.”