EPA Administrator Gina McCarthy's gift to America on its birthday was to share an Earth Day video about how the EPA is committed to saving the bald eagle, one of the nation's most cherished symbols of freedom.

In a tweet sent out Saturday, "Wishing everyone a happy 4th of July!" McCarthy posted a link to an April 22 YouTube video touting the EPA's 43-year-old ban on DDT, a controversial pesticide that was attributed to decreasing numbers of bald eagles in the United States.

"DDT, a dangerous pesticide, once pushed the bald eagle to the brink of extinction," read words appearing on the 30-second video, featuring the backdrop of a screeching bald eagle. "We helped change that. Because here at EPA, Earth Day is every day."

The video is referring to the EPA's 1972 ban on the controversial pesticide DDT, announced by then-EPA Administrator William Ruckelshaus.

In 1963 there were 487 nesting pairs of bald eagles remaining in the United States and the species was in danger of extinction, according to a fact sheet from the U.S. Fish and Wildlife Service, last revised in 2007. Habitat loss, shootings, and DDT were cited as contributors to the national bird's demise.

By 2007, the Service saw progress in bald eagle rehabilitation, estimating that there were at least 9,789 nesting pairs of bald eagles in the contiguous United States.