During the fall of 1969 a helicopter was evaluated for censusing waterfowl in Louisiana by comparing it with a Cessna 210 airplane. The comparisons indicated that while a helicopter equipped with flotation gear was a safe and highly effective vehicle for censusing waterfowl, twice as much actual flight time was required to complete the same amount of work and operational costs were double those for the airplane. About 1.5 times as many waterfowl were recorded from the helicopter as from the Cessna. However, statistical analysis indicated the difference between aircraft in the total number of ducks recorded was not significant. In contrast, significantly more mottled ducks (Anas fulvigula maculosa) were recorded with the helicopter, indicating it was more effective than the Cessna for counting this species. A test of interaction between aircraft and months was not significant; thus, each type aircraft measured the same rate of change in total duck numbers from August-September to November. This suggests that both aircraft are equally effective in measuring large changes in waterfowl populations by the transect sampling system. The helicopter provided advantages over the Cessna in visibility, slower air speed, and creates a noise level that induces inactive ducks to move. Its light fuel load, slow cruising speed and operational costs were major disadvantages. Considering the results of this study, the Louisiana Wild Life and Fisheries Commission plans to continue using the Cessna 210 for waterfowl inventories. There are plans to improve it for this type of work with a Robertson STOL Conversion. This will reduce a 21O's stall speed from 70 mph to about 40 mph and allow safe flying at 60 mph. Small helicopters will hopefully be used more often in situations requiring their unique flying abilities.
