This is 100% roadside birding. You are traveling the dirt-surfaced County Road A-1, also known as Laguna Madre Road, six and two-thirds miles between fenced prairie on either side, all private pastureland except for south of the road for a third of a mile at the hotspot's eastern end;  that eastern property is part of Maxwell National Wildlife Refuge.  

Descriptions of this hotspot may appear at first glance to be confusing, because CR-A1 travels both east-west and north-south, making right-angle turns. Starting at the northwest part of the Refuge, the CR-A1 route goes west from Lake 13 Road two-thirds mile, north 1 mile, west 1.5 miles (not quite to the entrance to Laguna Madre, and then south 3.5 miles to NM-505. To bird in the reverse (clockwise) direction, you would first travel 5 miles west on NM-505 from its intersection with NM-445, then take CR-A1 north.