Kerry Kriger is the founder and executive director of Save the Frogs, an amphibian advocacy organization.
"About one-third of the world's amphibian species are on the verge of extinction. And 200 species have gone extinct in the last 30 years," he says.
Kriger says there are lots of reasons for that: "Habitat destruction. Climate change. Taking them out of the wild for frog legs, dissections, to use them as pets, pollution."
Sam Lindsay and his mom, Marianna, got up before dawn to catch a train from New Jersey so they could attend the rally. Lindsay says, but worth it.
"I like frogs. They're my favorite kind of animal. And frogs need to be saved.
Kriger says frogs are crucial to the earth's ecosystem.
"Lots of animals eat and depend on frogs as a food source," he says. "Frogs disappear, lots of other wildlife disappears."