Re-introduction of the oriental pied hornbill in its historical range in Singapore

Summary

The southern oriental pied hornbill (Anthracoceros albirostris convexus), extinct in Singapore for over a century until a pair was found nesting on outlying Pulau Ubin in 1994, remained confined there when the Singapore Hornbill Project began in 2004 to study its breeding biology and extend its range to the urbanized mainland. The team, working with the National Parks Board, developed artificial nest boxes excluding predators like civet cats and pythons, first tested successfully on captive birds before installing them at enriched mainland sites; nests were also equipped with HD cameras and environmental sensors enabling detailed study of the breeding cycle, revealing previously undocumented infanticide-cannibalism. Growth was supported by two further releases of captive-bred birds donated by Wildlife Reserves Singapore and by translocating individuals from the Ubin stock to maintain genetic diversity, with genetic studies by the National University of Singapore; a couple of males were also GPS-tagged to study movement. After six years, the population exceeded 100 birds with 10 confirmed breeding pairs, most starting in artificial nests before shifting to natural cavities, suggesting it may self-regulate around nest-site availability without further intensive management, though genetic diversity will need ongoing monitoring. Difficulties included finding suitable habitat and food in a highly urbanized environment and educating residents to avoid conflict with or capture of the birds. The project rates itself successful, crediting sustained government and partner support, effective habitat enrichment, positive public reception, high-tech monitoring equipment, and a stable team over the full six-year effort.