249 



The Value of 0. aenesaens as a Biocontrol Agent 



In manure having the desired moisture range, 0. aenesaens may aid 

 in house fly control if laboratory results are indicative of field re- 

 sults. At the tilling site, larvae of Ophyra sp. were only found singly 

 or in pairs, and never in pockets or hot spots like M. domestiaa. This 

 type of behavior would limit the value of Opkyra as a house fly predator, 



if a manure, management program is drying manure enough to provide 

 good house fly control, this would also preclude the development of 

 other diptera such, as Ophyra, whose moisture requirements are similar to 

 those of M. domestioa. 



Adults of Ophyra were never noticed at the tilling site except in 

 light trap catches (Table 40) . In large numbers, these flies can be 

 especially bothersome. Adults are particularly bold and are not intimi- 

 dated by the usual methods employed to chase flies from clothing or body 

 surfaces (P. G. Koehier, personal communication) . 



Rearing Ophyra aenesaens in the Laboratory 



Ophyra aenesaens was colonized and reared with the same relative 

 ease as M. domestiaa. Life cycle from larva to adult averaged 14 days 

 at 29-4 C and the average life span for males and females was 16.5 to 

 20 days respectively. These results were almost numerically the same 

 as those of Johnson and Venard (1957). 



When kept in the growth chamber at 29.4 C, larvae of 0. aenesaens 

 raised the temperature of their growth medium to 42.4 C on day 2. The 

 temperature dropped daily and reached 30.0 C on day 7. When Johnson and 

 Venard (1957) found larvae of 0. aenesaens in the field, temperatures of 

 larvae media ranged from 35.6 C to 41.1 C. 



