Rare bird species found here include the Ceylon frogmouth and great Indian hornbill. The 2006 winter bird survey discovered the long-legged buzzard, a new species of raptor at Sispara, the park's highest peak. The survey found 10 endangered species recorded in the IUCN Red List including the red winged crested cuckoo, Malabar pied hornbill and pale harrier. The area is home to 15 endemic species including the black-and-orange flycatcher. It recorded 138 species of birds including 17 species that were newly observed in the Silent Valley area. The most abundant bird was the black bulbul.