|Platymantis polillensis, a forest frog only found in Luzon that was considered critically endangered by the IUCN. Photo by Rafe M. Brown, University of Kansas; ZooKeys
MANILA, Philippines - New animal species could be living in the Sierra Madre mountain range in Luzon, scientists said.
More than 101 species were documented in Sierra Madre by a team led by American scientist Rafe Brown of the University of Kansas, according to a scientific paper published February 7 in the journal ZooKeys.
Brown said more than a third of the species discovered could be new to science.
"Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning)," he said.
He urged a more extensive study of the northern Philippines to determine the new species.
"This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study," Brown said.
The research team, which included American, Filipino, and Dutch scientists, found 29 amphibians, 30 lizards, 35 snakes, 2 freshwater turtles, 3 marine turtles, and two crocodilians in their study of the Sierra Madre mountains.
The study was based on several surveys in the towns of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao in Cagayan Province, as well as Cabagan, San Mariano, and Palanan in Isabela. It also used historical museum records.
Brown said majority of the animal species surveyed in the Sierra Madre mountains can only be found in the Philippines.
"The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined," he added.
The species found in the mountain range include two forest frogs that have been earlier declared endangered by the International Union for Conservation of Nature (IUCN).
Other amphibians in the area are also on the IUCN's "near threatened" list.
The Philippine cobra, the Philippine cylindrical snake, and a venomous pit viper species were among the 35 species of snakes found by researchers.
They also discussed the Philippine freshwater crocodile that is endemic to the country.
"Conservation of Luzon's vertebrate biodiversity—in particular the more spectacular Philippine evolutionary radiations and complex ecological communities supported by the remaining forested areas of Luzon—remains an on-going effort, challenged by rapid development, large-scale extractive logging and mining industries and conversion of natural habitats into agricultural lands driven by a burgeoning human population," Brown said.
He said some forest regions close to the country's large cities in Luzon remain among the least studied.
"In the northern Sierra Madre where, despite the fact that large areas are protected on paper, threats to the remaining large tracts of forested areas have been clearly identified," Brown said.
He said a major challenge will be to monitor the animal species and their ecosystem through time to assess their responses to land use changes, climate change, resource extraction, introduced species, emerging infectious disease, and habitat degradation.
"Tremendous opportunities exist for future studies in taxonomy, biogeography, ecology and conservation of northern Luzon’s amphibians and reptiles," he added.