Bentson State Park is another location birders visit in Texas' Lower Rio Grand Valley. For us the disadvantage of this park was their admission fee; our senior Federal passes did not allow us free access to state parks. We visited Bentson twice and listed a few different birds. One is the Golden-fronted Woodpecker, a tropical American species that ranges north through Texas to Oklahoma.
Not only does this woodpecker look similar to Red-bellied Woodpecker, the two species hybridize. Golden-fronted Woodpeckers have expanded northward. Apparently hybridization occurs where contact between the two species is recent (Husak and Maxwell 1998). Surprisingly, neither the interbreeding, nor this woodpeckers' biology in general, has been well-studied by ornithologists.