In 2006, China's Yangtze River Dolphin was declared extinct.
Today there are approximately 2,500 Chinese white dolphins - also known as the Indo-Pacific humpback dolphin - living in the Pearl River Delta area. It is estimated that the number of dolphins has fallen by more than half in just seven years.
In Hong Kong waters the numbers have steadily decreased, from 160 dolphins in 2003 to about 75 in 2010.
The dolphins? Pearl River Delta habitat, in the waters off China?s industrial heartland of Hong Kong, Macau and Guangdong province, is under threat from what could be two of the world?s largest engineering projects. The first is a 50-kilometer-long bridge and highway network that is being constructed to develop economic connectivity in China?s industrial heartland. The second is a proposal to build a third runway at the Hong Kong International Airport, which is close to operating at full capacity.
In this photo essay, Ivan Broadhead examines the dolphins' chance for survival in the face of these odds.