The China Bird Net have several posts of bird hunting in China Mainland. The poisoning of duck in Heilunjiang is describe in this post. Even if you cannot read Chinese, there are photos that show you the scale of the problem.
http://www.chinabirdnet.org/BBS/ ... 1071&highlight=
http://www.chinabirdnet.org/BBS/ ... 1068&highlight=
HF Cheung