Plague vector studies. IV. A comparison of insecticide application techniques for flea control on ground squirrels.

Abstract

An evaluation of the long term residual life of Dieldrin based on the flea index indicated that from the second month through the twelfth month post-treatment the flea index was less than 0.4 fleas per squirrel in 3 of the treated fields, while the control index ranged from 60.5 to 419.5 fleas per host. From the third to the sixth day post-treatment the flea mortality was higher in study areas treated by direct burrow application of Dieldrin (96.3% and 98.0%) than in those study areas where application was by the surface or area method (92.6% and 95.8%). Burrow treatment resulted in a more rapid knockdown of fleas than did surface treatment. These data are based on 89,028 fleas collected from 1423 California Ground Squirrels; the 3 species present of fleas were Diamanus montanus, Hoplopsyllus anomalus , and Echidnophaga gallinacea.