Heybud, that 50 acre minimum may be for your county : "The ratios chosen by the county are based on the region in which the county is located. According to the ratios set up by the Texas Parks and Wildlife recommendations, the smallest tract of land that could qualify for an exemption would be 12.5 acres, except for some exceptions. Landowners who had a wildlife exemption prior to Jan. 1, 2001 will be grandfathered regardless if they meet the ratios or not."
p.s. Awesome pond !