Status survey and conservation action plan for Chinese grassbird Graminicola striatus in Hong Kong, China

Abstract

The aim of this study was to provide a status survey and conservation action plan for Chinese Grassbird Graminicola striatus in Hong Kong. Chinese Grassbird is currently listed as ‘Near Threatened’ on the IUCN Red List of Threatened Species. However, its status is likely to be more endangered if a new assessment will be done. It is because the current status was based on the assessment of ‘Graminicola bengalensis’ which has been recently spilt into Chinese Grassbird and Indian Grassbird (G. bengalensis) due to their different genetics, morphology, vocalization and geographical distribution. This study is the first conservation action plan for the Chinese Grassbird in the world.

A territory-wide survey was conducted to assess the population of Chinese Grassbird in Hong Kong. A total of 101 birds were estimated from 19 sites. Based on the actual count and density of birds of surveyed grassland (km²), a total of 305 birds were estimated for these 19 sites. The result also showed that larger grassland sites support significantly more Chinese Grassbirds. Most Chinese Grassbirds were recorded between 401 and 800 metres and recorded at taller grasses of between 0.8and 1.3metres. Grassland was its major habitat and most birds were found foraging in grasslands dominated by Arundinella setosa, Indocalamus sinicus, Miscanthus sinensis or Lepidosperma chinense.

Chinese Grassbirdis a narrowly distributed species based on current knowledge of its global distribution. The whole global population is presumably not more than 5000 birds. Although Hong Kong is considered a stronghold of this species, the local population was estimated to be no more than 305birds approximately. The population shall be declining and is more vulnerable to extinction due to its intrinsic ecological limitations, natural vegetation succession and reforestation, the effects of climate change, interspecific and intraspecific competitions, natural predators’ effects, grazing by increasing feral cattle population and other anthropogenic activities. A set of recommendations were made in the conservation action plan in order to save this species from extinction. The most imminent task is to identify the key grasslands that hold significant numbers of Chinese Grassbirds and maintain them as grassland. Grassland corridors should also be maintained whenever possible between these focal areas. 360