Abstract:The Blue-crowned Laughingthrush, Garrulax courtoisi, quite recently split from G. galbanus to be a separate species, is hence an endemic bird to southern China, with two rather isolated subspecies, the dominant in SE China and the race simaoensis in SW China. And, due to so small of its far known population as well as so tiny of the viable breeding habitats that those birds preferring for nesting, the Blue-crowned Laughingthrush is listed amongst the Critically Endantgered (CR). According to the results of our field studies since 2000, the dominant race of the bird, courtoisi, is mainly restricted to Wuyuan of NE Jiangxi, SE China, particularly during the breeding season, nesting in flocks in trees in and/or around those lowland villages and towns showing high collaboration in its breeding efforts. Ususally, and statistically, for a good breeding season, number of nests of the first clutch for a breeding flock would be no more than 1/3 of the number of birds in the flock, and less than 1/5 of the second if their first clutch failed, no third clutch ever observed; and, as to be the best result, those chicks of the year which can get enough developed for leaving the breeding site with the adults would be no more than 1/4 of the number of the adults in the flock, while, some flocks in some years would have no chicks at all, mostly due to predation but sometimes also due to human disturbance. It is currently confirmed that the whole colony of the dominant, courtoisi, consisting of 9 breeding flocks, with over 300 individuals in total of its population, showing a trend of slightly increasing in the last 5 years. Whereas, until now, though constant seeking effort being undertaken for more than 10 years, no flocks or even individuals of the race simaoensis could have been virtually re-found in all the known localities and in relatively larger surroundings, both in S Yunnan and in W Guangxi, of SW China.