Ecology of Mosquitoes in the Wichita Mountains Wildlife Refuge1

Abstract

Because of the unusual topography, climatic conditions, isolated semi-natural conditions, and biotic associations in the Refuge, the mosquito fauna includes a wide variety of eastern and western species of mosquitoes, which fact would suggest that the Refuge is an area of transition or ecotone. Thirty-three species of mosquitoes distributed among 2 subfamilies and 10 genera were collected. The largest numbers of larval collections were made from tree-hole (22.6%), pooled-stream (19.6%), and rockhole (13.6%) habitats. The most abundant larval mosquitoes collected were Aedes triscriatus (Say) and A. atropalpus (Coquillett). The most abundant species of adult mosquitoes collected were Culex erraticus (Dyar & Knab) and Anopheles quadrimaculatus Say. Species associated with the transient type larval habitats usually completed their larval development in relatively short periods. However, the developmental period of Psorophora discolor (Coquillett) was considerably longer. Larvae associated with the transient type larval habitats were nearly always species of Aedes or Psorophora. The permanent type larval habitats, particularly impoundments, provided a relatively small number of C. erraticus and Anopheles quadrimaculatus larvae. Larvae were most abundant in this type habitat when aquatic vegetation and intermittent shade were present. A comparison with light-trap collection records gathered in 1947, indicates that the incidence of A. quadrimaculatus has increased considerably, whereas, that of C. tarsalis Coquillett has decreased sharply. Aedesatropalpus and A. zoosophus Dyar & Knab are much more abundant at the Refuge than previously indicated in the literature. Laboratory experiments suggest that the seasonal periodicity of tree-hole species of mosquitoes appears to be directly related to temperature rather than length of photoperiod.