What is "la grulla"

Population (2000): 1211
Housing Units (2000): 468
Land area (2000): 0.583829 sq. miles (1.512110 sq. km)
Water area (2000): 0.001101 sq. miles (0.002851 sq. km)
Total area (2000): 0.584930 sq. miles (1.514961 sq. km)
FIPS code: 40288
Located within: Texas (TX), FIPS 48
Location: 26.269278 N, 98.647067 W
ZIP Codes (1990):
Note: some ZIP codes may be omitted esp. for suburbs.
Headwords: