​Highline Lake is surrounded by the high-altitude desert that stretches from the Western Slope of the Rockies to the Eastern Slope of the Sierra Nevadas. Most of the mammals in the park are nocturnal and only come out at night, but you can see squirrels, rabbits, prairie dogs, mule deer, and lizards and snakes of several varieties during the day. Migrating birds often stop to rest at Highline Lake, while some spend the entire winter season here.

Bird, plant and wildlife guides are available at the park book store or on Highline Lake State Park's iNaturalist app observations for Android and iPhone. iNaturalist is a free online social network and citizen science platform that allows users to record and share observations of biodiversity. By uploading photos or sounds of wild organisms, you can get help identifying species from a global community of naturalists and even an automated identification tool. Using iNaturalist helps you learn about local nature, connect with other enthusiasts, and most importantly, contribute valuable scientific data to biodiversity research and conservation efforts worldwide.