The behavior of nose bot flies (Cephenemyia apicata and C. jellisoni) when attacking black-tailed deer (Odocoileus hemionus columbianus) and the resulting reactions of the deer

Larviposition behavior by Cephenemyia jellisoni involved a covert, inaudible hovering–"stalking" flight with attacking females usually remaining undetected until the moment of larviposition. In contrast. C. apicata landed on or near deer and became objects of attraction eliciting the curiosity of deer and causing them to orient to the fly in a position vulnerable to larviposition. The final phase of attack by C. jellisoni was initiated from a blind spot in front of. and below, the deer's nose, whereas visible C. apicata attacked from perched positions. After flies squirted larvae into deer's nostrils, deer jerked back their heads and sneezed as they simultaneously shook their heads and lowered their noses to the ground. A series of other post-larviposition behavioral responses of deer are described, as is their characteristic fly alert position and behavior. Encounters with C. apicata and C. jellisoni females that larviposited in their nostrils led to the recognition of these flies by educated deer and to their responding with anti-nose-bot-fly behavior resulting in their evading females attempting to tarviposit. Deer did not respond to flies presented for them to smell, but when tethered C. jellisoni hovered in view of experienced deer, deer exhibited the characteristic evasive reactions provoked when wild flies were spotted. Deer also responded similarly when Cephenemyia larvae were "finger inoculated" into their nostrils.

NOTES ON THE LIFE HISTORY AND MORPHOLOGY OF CEPHENEMYIA JELLISONI TOWNSEND AND LIPOPTENA DEPRESSA SAY, TWO DIPTEROUS PARASITES OF THE COLUMBIAN BLACK-TAILED DEER (ODOCOILEUS HEMIONUS COLUMBIANUS (RICHARDSON))

Material derived from deer taken on southern Vancouver Island, B.C., represents all larval stages of the nostril fly, Cephenemyia jellisoni Townsend. Description is given of the external morphology of the three larval stages and the puparium of this fly. The tracheary system of the first instar, and the cephalopharyngeal apparatus of all three are described and figured.In November and December first instar larvae were found in the nasopharynx of the host where they remained until after the moult. Until they reach maturity, second and third instar larvae occupy the retropharyngeal recesses of the deer. They leave the host by way of the nostrils and pupate in the ground.Observations on the life history and behaviour of Lipoptena depressa Say, both on and off the host, are given. It is postulated that the life span on the host varies from 8 to 13 months and that during this period from four to seven larvae are produced. Larvae do not pupate on the host but fall to the ground as soon as they are liberated. Infestations on a single host may consist of more than 2000 flies; under such circumstances the deer evinces discomfort. As yet this fly is not known to be involved in the life cycle of any internal parasite of the deer.