The Hill Country is argued to be one of the best birding spots in Texas. The scissor-tailed flycatcher, hooded oriole, greater roadrunner, painted bunting, blue bunting, and more recently the Green Jay and Caracara are gems for visiting ornithologists. Just in time to accommodate this new industry at the Annandale, green jay populations have flourished throughout the Hill Country and South Texas Brushlands in recent years. These colorful and charismatic birds might be considered the epitome of a tropical bird that has become established north of the Rio Grande. It is one of the most sought after birds that birders come to Texas to see; a target species for thousands of birders who flock to South Texas annually.

Uvalde County contains habitat considered suitable for ten federally threatened or endangered fauna species.

Of these, the golden-cheeked warbler have nests in the northern portion of the ranch. This striking bird depends on stands of mature ashe juniper mixed with deciduous trees.

In addition, the black-capped vireo has been spotted on occasion at the ranch, west of the Frio River. These tiny birds are suffering considerably due to the numerous cowbirds in the area, so efforts to preserve their habitat is a high priority.

Habitat for both the black-capped vireo and the golden-cheeked warbler were included as non-development zones in the third conservation easement. These non-development zones should ensure that the threat of habitat degradation is no longer a danger to the threatened and endangered species within the Annandale.