Is it too ironic that endangered species would be united snugly with the cause of preventing unwanted pregnancies? Not for the Center for Biological Diversity, which every year highlights the link between population growth and species extinction by giving away tens of thousands of condoms decorated with endangered animals and quirky slogans.

Can't Refrain? Remember the Whooping Crane / Fumbling in the Dark? Think of the Monarch

Across the country today, 500 volunteers will give away 50,000 free Endangered Species Condoms at Earth Day events and on campuses across the country, and in venues from tea shops to tattoo parlors. "Nothing sparks a conversation like handing someone a condom, especially when it comes with a slogan like ‘Before it gets hotter…remember the sea otter,'" said Stephanie Feldstein, population and sustainability director at the Center.

More than a half million Endangered Species Condoms have been distributed since 2009 at events like Earth Day and World Population Day, and on Valentines Day.

Since the first Earth Day in 1970, global population has nearly doubled, while wildlife populations have plummeted. The Center's campaign promotes universal access to family planning, contraception and reproductive healthcare, education and empowerment for women and girls.

Sadly, you can't buy 'em anywhere–you'll just have to get lucky.