Using citizen-science reports to document range expansion of the introduced Chinese Water Dragon (Physignathus cocincinus) in Hong Kong

Abstract

The first incursion of Chinese Water Gragons (Physignathus cocincinus) in Hong Kong occurred in October 2004 on Tsing Yi Island. This study identified a further 54 citizen-science reports of dragons in different locations of Hong Kong. Although there were no subsequent reports from Tsing Yi Island, there were recurring reports in five other locations. In Aberdeen, reports started in 2010, concentrating on the grounds of Ocean Park. There were also numerous reports from the Kam Shan Country Park since 2010, the Pok Fu Lam Reservoir since 2011, the Lion Rock Country Park since 2012, and the Sha Tin District since 2014. Dragons were mostly observed in natural areas, but also in urban areas. The highest number of sightings were reported in April. Combinations of males and females were identified in four of the locations with numerous reports, suggesting that these populations are self-sustaining.