Hundreds of endangered tadpoles are growing up in a nursery in Long Beach, California, in the United States. Their carers have one goal: help them become strong enough to return to mountain streams.
At the Aquarium of the Pacific, staff feed the young mountain yellow-legged frogs, check their development and prepare them for life outside their tanks.
The work recently reached a milestone. More than 1,000 frogs raised at the aquarium have now returned to the wild through a conservation programme involving zoos and government agencies.
In August, teams released 653 southern mountain yellow-legged frogs into California’s San Gabriel Mountains. The aquarium had raised 394 of them. All came from the Los Angeles Zoo’s breeding programme.
The animals need help because their mountain homes have become increasingly dangerous. Trout introduced by people eat tadpoles, while a fungal disease threatens the frogs. Wildfires and the mudslides that follow can also damage their streams.
The aquarium joined the recovery effort after the Bobcat Fire in 2020, helping care for tadpoles rescued from affected areas.
Inside the nursery, staff feed tadpoles four or five times a day. They spread food on small plates so the animals can graze much as they would on rocks in a stream, The Associated Press reported.
As the tadpoles develop legs and lose their tails, their needs change. Young frogs eat insects, and carers vary the water flow to help them build strength and get used to different conditions.
Raising the animals through this early stage gives them a better chance when they enter the wild. Larger, more developed frogs are less vulnerable to predators than small tadpoles.
The August releases took place on two days, with teams returning the frogs to streams in their native habitat. They added to nearly 7,000 Los Angeles Zoo-bred frogs released since the wider recovery programme began.
The nursery’s success depends on what happens next: these young frogs surviving, growing and eventually producing a new generation in the mountains.
