This beautiful state park is one of the best places to bird near Denver. It would be easy to spend most of a day birding here, and the best time to visit tends to be in late spring through summer. An extensive trail system runs through the canyon and allows access to a variety of habitats including scrub oak woodlands, montane forest, and grasslands. Canyon Wrens sing and White-throated Swifts fly above as as you walk in the canyon. Trails continue through scrub oak woodlands, where you can spot Ovenbird and Common Poorwill. The montane forest is rich with Stellar’s Jay and Cordillerean Flycatcher and in the grasslands, look for Western Meadowlark and Vesper Sparrow.
Many birds nest and raise their young in the park; a unique dry-land heronry even once occurred in the park, where Great Blue Heron nested. Several raptors may be observed as well, including Swainson’s Hawk, Cooper’s Hawk, Red-tailed Hawk, and several falcon species, such as American Kestrel. Also keep your eye out for Lazuli Bunting, Virginia’s Warbler, Woodhouse’s Scrub-Jay, Plumbeous Vireo, and Bushtit.
Castlewood is home to one of Colorado’s larger Turkey Vulture populations; they are a common sight riding thermal updrafts created as the rocks warm each morning. The park celebrates their return from migration with Welcome Back Turkey Vulture Day each spring. A State Parks pass is required for entry.