Rhinoceros Hornbills (Buceros rhinoceros) are a vulnerable species with declining populations in Thailand, Sabah, Sarawak and Peninsular Malaysia, Kalimantan, Sumatra and Java, Indonesia and Brunei. The species is threatened by hunting and loss of habitat to logging, plantations and agriculture. 16 zoological institutions, including Chester Zoo, hold this species in captivity and are participating in the European Endangered Species Programme (EEP) in order to create and maintain a genetically viable and sustainable safety-net population in captivity.
Chester Zoo last successfully bred Rhinoceros Hornbills and contributed to the EEP population in 2006. Over the past 2 years Chester has taken a holistic approach in adjusting the management and husbandry techniques for this species with a view to improving their welfare and reproductive success while collecting valuable data on their behaviour, preferences and the reproductive process.
A series of enclosure changes, dietary adjustments and the introduction of positive reinforcement training, recognising the birds’ individual differences, have resulted in improved physical condition of their founding Rhinoceros Hornbill pair. This has led to the successful rearing of two invaluable Rhinoceros Hornbills chicks at Chester Zoo in 2019.
The main aim of this project was to successfully breed Rhinoceros Hornbills at Chester Zoo after a long non-breeding period, focusing on the founding pair. During this time, staff gathered as much information on their needs, preferences, behaviour and reproductive process as possible. They also aimed to improve the welfare of our birds, as measured through their physical condition (general fitness, plumage, colour and condition of casque and skin), their expression of natural behaviours and their interactions with their environment, their keepers and one another.
Rhinoceros hornbills are currently listed as vulnerable by the IUCN but wild populations are suspected to undergo a large reduction over the next three generations as their lowland primary forest habitat is being lost to human activities such as logging and agriculture. These birds are also subject to illegal hunting. With low rates of reproductive success in captivity, the goal to retain 90 % of gene diversity at the end of 100 years is not possible without an increase of the reproductive rate, especially for the living founders who have not yet bred. Meaning, every successful breeding is an extremely valuable addition to the EEP population.
Gathering data on seasonal dietary provisions, courtship, nesting behaviour and chick development will help us to replicate success in the future. Information on husbandry and management of this species could contribute to the EAZA Hornbill Husbandry Guidelines. Data on the environmental parameters from artificial nest boxes used at Chester Zoo can contribute to their in-situ partnership.
Chester Zoo won a Gold in the BIAZA Animal Husbandry, Care and Breeding category of the annual awards 2020 for this work.