The wreathed hornbill is listed in IUCN Red List as Vulnerable and as an Appendix II species in CITES. Under national regulation, wreathed hornbill is protected under Regulation of Minister of Environment and Forestry No. 20 of 2018, Law No. 5 of 1990 and Government Regulation No. 7 of 1999.
In Indonesia, wreathed hornbill occurs in Kalimantan, Sumatra, Java and Bali (including a number of offshore islands). The species lives in lowland forests and hills up to 2,000 m asl. Its range extends to southern Bhutan, eastern India, southwestern China, Southeast Asia, and the Malay Peninsula.
Wreathed hornbill measures 75-85 cm in length. Male wreathed hornbill weighs 1.6-3.6 kg while female weighs 1.3-2.7 kg. Its back, wings, and abdomen are black with a metallic green tinge and a long white tail. Its long beak is pale white to yellowish. Its casque has low folds and clear, vertical dark orange-brown wrinkles on both upper and lower mandibles.
The feet are grayish green. Male wreathed hornbill has a brick red crown and nape with white to cream-colored face and neck. Its circumorbital skin is red with pink eyelids. The male’s iris is dark red with a narrow blue ring. Underneath the bill is a yellow, featherless gular pouch with broken blue-black lines across the middle.
Female wreathed hornbill is smaller in size. Its head and neck are black with a blue gular pouch, with similar black lines as the male. The female’s circumorbital skin is red with dark brown iris and a narrow blue ring.
The wreathed hornbill eats fruits including figs and fruits of the walnut family, ironwood, and mahogany trees. In Kalimantan, its primary food is lipid-rich fruits available during certain fruiting seasons. This hornbill species also eats small animals including bird eggs, small birds, tree frogs, and small bats, snakes, lizards, and invertebrates.
During the breeding season, wreathed hornbills need large and tall trees with natural cavities. The hole is then plastered by the female using its feces and food remains. The female lays 2 eggs but usually only 1 chick survives into adulthood. The species spends 111-137 days nesting: 13-14 days to prepare the nest and lay eggs, 40 days incubation, and 90 days raising the chicks.
In Kalimantan the breeding season lasts from January to May when fruit is abundant. Meanwhile breeding season in Sumatra is year-long except for December, and January, July-September in Java.
Wreathed hornbill cannot tolerate habitat loss and require vast and protected territory. The species is hunted locally and its population is expected to decline 30-49% in the next three generations. Therefore, the species is proposed to be uplisted to Vulnerable in the IUCN Red List.
The wreathed hornbill has a unique call that sounds like repeated, short and raspy barks. When flying, its wing flaps are loud and can be heard from 1 km away. The wing flaps are quieter when the feathers are wet. This species does not glide or soar as much as other hornbill species when flying.