Rufous-necked hornbill

The rufous-necked hornbill (Aceros nipalensis) is a very large hornbill, measuring 90 to 100 cm in length.
The male rufous-necked hornbill is slightly larger and weighs 2500 grams whereas the female weighs around 2200 grams. These species are sexually dimorphic, the male has reddish brown head, neck and underparts. The upperparts in male are black and the black wing has white-tipped outer primaries.
The female rufous-necked hornbill has black head, neck and underparts. The juveniles have plumage similar to males but their bills lack dark ridges. The tail in adult is long and the basal half is black and the distal half is white.
The bill is pale yellow in adult and has a row of vertical dark ridges on the upper mandible. The casque is almost absent. There is red gular skin. The irises are brownish red and orbital skin is pale blue. Their call is a loud barking “kok..kok” sound. The rufous-necked hornbill species are distributed in India, Nepal, Bhutan, China (southern Yunnan and south-east Tibet), Myanmar, Laos, Thailand and Vietnam. It is probably extinct in Nepal and almost extinct in Vietnam.
In India, these rufous-necked hornbill species are distributed in the states of northern West Bengal, Assam, Arunachal Pradesh, Meghalaya, Nagaland, Manipur and Mizoram.
The Important Bird and Biodiversity Areas (IBA) of the rufous-necked hornbill species in China are Yarlung Zangbo Daxiagu Nature Reserve, Xishuangbanna, Nabanhe Nature Reserve and Lhakhang. The IBA in Vietnam are Pu Mat and Che Tao.
The natural ecosystems of these hornbill species include tropical and subtropical moist montane forests, tropical and subtropical moist lowland forests, dense evergreen forests, broadleaved forests, deciduous foothill forests and dry woodlands. The diet of these rufous-necked hornbill species is mostly fruits. Berries, drupes, fruits of Lauraceae spp., Moraceae spp., Meliaceae spp. and Annonaceae spp. are their primary food.