6 THE- AUDUBON? BU TG Baie 
order of those used commercially in Reelfoot Lake, Tennessee. About 500 
pounds of healthy carp were in the net, although the DDT had only been 
out for about 48 hours. 
Twenty-four hours after the October spraying, where the pilot had 
made three runs over the same channel west of the headquarters building, 
and, combined with a strong breeze which had drifted the heavy oil spray 
into one shore, some loss of fish life was noted. One 12-pound carp, 
evidently affected by DDT, ran ashore and was placed in a small pond 
for observation along with three toothed herrings (Hisdon tergisus). The 
carp recovered in two days while the herring succumbed. At the same 
place shiners came ashore, but in a bucket of water dipped from along the 
shore these likewise recovered after 24 hours. Several other “sick” fish 
were noted along the shore. One effect of the DDT might be said to make 
fish more readily available to fish eaters. DDT must have piled up along 
this shore at the rate of several pounds per acre. 
Summary 
From these tests, with the careful preparation made by the Sixth 
Service Command, results show that mosquitoes can be readily controlled 
with 5 per cent DDT in No. 2 fuel oil sprayed by planes at the rate of 
between 0.2 and 0.5 pounds per acre. At these levels, provided the spraying 
is accomplished by experienced pilots who are familiar with the area 
covered and with favorable climatic conditions, little harm will result to 
fish and wildlife. After August 1, few nests of birds are occupied. As 
the Anopheles breeding season in this Upper Mississippi area normally 
begins at this time, spraying from August to October—at 30-day intervals 
—is relatively safe. If there is agitation for controlling “nuisance” 
mosquitoes as early as May or June, then bird nesting populations would 
be affected through removing the food supply. 
Certain species of fish, notably toothed herring and several species of 
shiners and dace, are killed at rates of 0.5 pounds of DDT per acre in 
agitated waters. In one case, while the quantity was not known, fish killed 
were at an accumulated rate several times that normally applied. 
Crayfish are readily killed at 0.5 pounds per acre and this may also 
have an effect on raccoon populations. This knowledge, however, may be 
of practical benefit in controlling crayfish in the South where they cause 
heavy losses to certain agricultural crops. 
CONCLUSIONS 
Results of the extensive application of DDT by airplane, without 
question show this to be an effective method in controlling mosquitoes. 
The possibilities of uniform application under proper weather conditions on 
river bottom forested lands has much to commend it over other methods 
applied from the ground. Relative costs on a private operational basis may 
prove to be the factor limiting the treatment of large areas. The possi- 
bility of commercial treatment of summer resorts is now a possibility with 
planes available on Government surplus property lists. Extensive coverages 
