A dog made the discovery of a lifetime when it discovered an animal believed to be extinct after it wasn’t seen for nearly 90 years.

The collie had been deployed by the Endangered Wildlife Trust (EWT) as a scent detection dog in a yearslong and nearly hopeless pursuit of finding traces of the De Winton’s golden mole. This shimmering mole rarely appears above ground and was last seen in 1936.

The blind moles live almost entirely underground and don’t leave behind tunnels like other species of moles. They appear to “swim” through the sand, according to a press release from EWT, and their extremely sensitive hearing alerts them to vibrations above ground, allowing them to burrow into the ground without being seen.