Invasive Birds in Japan

Abstract

Introduction of exotic birds has been increasing throughout the world. We conducted inquiry investigations in order to reveal the spread of introduced bird species in Japan. Forty-three exotic species are known to breed or are regarded as breeding. The Feral Pigeon (Columba livia), Chinese Bamboo Partridge (Bambusicola thoracica), Red-billed Leiothrix (Leiothrix lutea), Budgerigar (Melopsittacus undulatus) and Red Avadavat (Amandava amandava) are widely distributed. The Rose-ringed Parakeet (Psittacula krameri manillensis), Common Peafowl (Pavo cristatus), Light-vented Bulbul (Pycnonotus sinensis), Melodious Laughing Thrush (Garrulax canorus), Crested Myna (Acridotheres cristatellus) and Black-billed Magpie (Pica pica sericea) are locally common, though they have limited ranges. Sightings of other species were sporadic and regionally limited. Most of introduced birds in Japan are escaped caged birds. About two thirds are from tropical regions, and show diet generalism as omnivores, granivores and frugivorous or herbivorous insectivores. Light-vented Bulbuls, Feral Pigeons and Common Peafowl exerted crop damage. Although adverse effects by exotic birds are not prominent yet, there is great concern that exotic birds will become a threat to native biota and habitats in future.