Description wikipedia

The Sierra Madre ground warbler (Robsonius thompsoni) is a species of passerine bird in the family Locustellidae. It is endemic to the island of Luzon in the Philippines, where it is found in the northeastern and eastern foothills of the Sierra Madre. Its habitat is in tropical moist lowland and the lower reaches of tropical montane forest. It was formerly conspecific and forms a species complex with the Cordillera ground warbler and Bicol ground warbler, which are some of most elusive birds in the country due to their extremely shy nature.While not officially threatened, its population is said to be declining due to habitat destruction through deforestation.