Brownsvilles Resaca de la Palma State Park boasts the largest tract of native habitat in the World Birding Center network. A "Band-celled Sister" butterfly.Etched by ancient curves of the Rio Grande, its 1200 semi- tropical acres provide a quiet retreat from the hustle and bustle of an international urban center only a few miles away. Through the cooperation of local, state and federal land management agencies, a wilderness preserved from days gone by is open to nature adventurers for the first time.