The Bill Williams River National Wildlife Refuge is found at the far reaches of southeastern Lake Havasu. Rumored to contain the largest surviving cottonwood-willow woodlands of the lower Colorado River, the Refuge covers 6,000 acres. Perhaps most importantly, the Bill Williams River serves as a comfortable refuge to over 300 species of birds and waterfowl. There is a number of endangered species currently in propagation, including the razorback sucker fish and bony-tail chubs—which are indigenous to the Bill Williams River. Additionally, the Audubon Society named the Refuge an area of global significance in 2011.