Eureka! These frothy fistfuls of frog eggs can mean only one thing. The California red-legged frog is finally back in the Santa Monica Mountains.

The discovery has researchers jumping for joy. Nobody—or almost nobody—has seen a California red-legged frog in those mountains for nearly 100 years. That’s partly because in the 1920s and 1930s, ranchers introduced a foreign species to the area. This stranger is a three-inch-long crayfish. People use it for fish bait. The crayfish eats insects, eggs, fish, and tadpoles. When it showed up, the red-legged frogs nearly disappeared from the mountains.

The researchers have been trying to bring the frogs back. In 2014, Park Service workers introduced 350 eggs to the area. They took the eggs from a population of rare, red-legged frogs in nearby mountains. The workers knew how creation works. In God’s reliable design, frogs can live and reproduce on their own. So the workers placed the eggs in a protective pen in a stream. Eventually, the eggs hatched. Now the eggs have become mature young frogs. They are probably the parents of the nine masses of new eggs that were found.

The new eggs mean this: The number of red-legged frogs might continue to grow without human help. When the researchers heard about the egg find, they shouted. They whooped. They high-fived. But they didn’t tell the eggs’ exact hiding spot. That’s their way of saying, “Baby frogs growing. Do not disturb!”