LAGUNA ATASCOSA. Laguna Atascosa is a saltwater lake in the southwestern region of Laguna Atascosa National Wildlife Refuge three miles west of Laguna Madre and five miles north of Bayview in northwestern Cameron County. Laguna Atascosa is four to five feet deep at its deepest. Needle Island is at its center (at 26°14' N, 97°23' W), and Cayo Atascoso serves as an outlet into Laguna Madre. The surrounding terrain is flat to rolling and is surfaced by soils ranging from dark calcareous clay to mottled organic-rich mud with concentrations of shell. Mesquite, grasses, and cacti grow in the area.