It's baby season for endangered species at the Philadelphia Zoo

The Philadelphia Zoo has been a leader in animal conservation in the United States.

As we get closer to the 5oth anniversary of Earth Day, we celebrate the Zoo's work protecting and preserving endangered species.

Spring is the season of beautiful blooms at the Philadelphia Zoo and new babies.

"This is the first bear cub born here in over 20 years," says Lauren Etkins, lead bear keeper.

Sloth bears are one of the most popular animals at the zoo.

"They are so energetic, and they have such great just natural behavior," says Donna Evernham, Curator Carnivores and Ungulates. "And then you add this cup into the mix."

That high energy cub's mom, Kayla, dealing with familiar new mom issues.

"Her hair was everywhere," Etkins says. "Her nails were all overgrown. She couldn't take care of them. And she looked tired."

But she is a doting mom and the two have a very close bond.

These births are part of the species survival plan, or s-s-p, a worldwide network of zoo's working together to enhance species conservation.

"That's to make sure we have genetic diversity for threatened and endangered species for the next hundred years," says Evernham.

Sloth bears are considered vulnerable in the wild because of their threatened habitat.

"Right now in the United States (zoos), there's only about 46 slough bears. So, this is a pretty big deal for us. And for the sloth bear population" Everham adds.

Philadelphia was at the forefront of SSP for the Guam kingfisher and the Guam rail.

The Guam rail and Guam Kingfisher were both declared extinct in the wild after the brown tree snake decimated their populations on Guam," says Ian Gereg, Curator of Birds, Reptiles and Amphibians. "We've had successful hatches of over a dozen Guam kingfishers and a half dozen Guam rails."

The Guam rail is no longer considered extinct and both animals are being reintroduced into the wild.

"That's what we live for. Talk about bucket lists. That's a bucket list moment," says Toni Flowers, Lead bird keeper.

The Zoo's primate preserves recently announced two baby black and white ruffed lemurs. The two babies join four brothers all born to father Hewey and mom Kiaka.

And they could be exploring the Zoo 360 trails by midsummer.

"We're going to have a total of eight ruffed tailed lemurs running this trail and making all kinds of noise," Brown says.

The zoo staff is still working hard and without any guests visiting they are trying to raise money to keep all the animals healthy and safe. If you'd like to help you can visit their https://philadelphiazoo.org/and support their Spring Back Fund.