Seven charges of Nitromon Primer S were exploded at six stations on the Aucilla River. Results of three explosions, each consisting of ten pounds of explosive, at Station No. 1 killed at least 842 shortnose gar, 300 longnose gar and three channel catfish. The successive treatments at this station indicated a reduction of longnose gar in the area. More shortnose gar were destroyed in the third explosion than in the first and second. Variation occurred in the results at other stations. It was noted gar concentrations could be detected by their surfacing activity. At all stations where this activity was noted, large numbers of gar were killed without destroying many fish of other species. At stations where this activity was not noted, frequently, numerous fish of other species were destroyed.