HNHC Volume 1, Number 1 Ardiantiono et al. Hornbill density estimates and fruit availability in a lowland tropical rainforest site of Leuser Landscape, Indonesia: preliminary data towards long-term monitoring Kinnaird & G. O’Brien Genetic monogamy in Von der Decken’s and Northern Red-billed hornbills Sibarani et al. Long-term monitoring of nesting behavior and nesting habitat of four sympatric hornbill species in a Sumatran lowland tropical rainforest of Bukit Barisan Selatan National Park Chan Sighting records of hornbills in western Brunei Darussalam Chittenden Trumpeter hornbill (Bycanistes bucinator) bill colouration Kinley et al. Nest cavity availability determines breeding in hornbills: Rufous-necked hornbill nest at breast height in Bhutan Zheng at al. Flocking of hornbills observed in Tongbiguan Nature Reserve, Yunnan, China Jain & Lee Update from the Helmeted Hornbill Working Group Datta & Kemp IUCN HSG Update and Activities