These birds are declining in Florida. What is causing their numbers to decrease?
These are White Ibis. Their numbers have been decreasing, and the University of Florida just released a study showing that it is due to mercury contamination in their food supply. The mercury interferes with their reproductive cycle. Instead of forming a pair bond with a female Ibis, the mercury causes the male Ibis to form a pair bond with another male instead. They build a nest, and spend a month taking turns sitting on the nest, which of course has no eggs. Pollution controls have lowered the mercury levels, but it is still high enough to cause problems in many areas.