PROVIDENCE, R.I. (WPRI) — The population at Roger Williams Park Zoo has grown by two.

Two red wolf pups, the world’s most endangered canid species, were born on April 29 at the zoo as part of the red wolf breeding program. 

They are the second litter of the parents Brave and Diego and the newest siblings to Saluda.

While the pups have been observed nursing and appear to be steadily gaining weight, the zoo says the next month is a critical time for their development.

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While Diego and Saluda may be visible in their habitat, the zoo says the two new pups and Brave will continue to spend most of their time in the den.

Guests may be able to catch a glimpse of the pups when they begin to venture outside of the den. Until then, the zoo says you can see updates on their progress on their Facebook and Instagram pages.

As of February, the zoo says there were approximately 235 red wolves in 49 Red Wolf SAFE facilities across the country. The birth of these pups is critical for the survival of this critically endangered species.

Red wolves were listed as extinct by 1980.