Most of the species of flies which commonly enter houses or restaurants and therefore are possible vectors of disease are attracted to baits composed of entrails, garbage, or feces. These flies can usually be collected by placing fly traps over such baits. Rather detailed population studies have been made of many of these common, saprophagous species. On the other hand, the writers noticed that certain museum collections contained very interesting, uncommon, or undescribed species of muscoid flies, principally Sarcophagidae, and that many of these specimens bore a mountain locality label. The writers, therefore, chose nearby Stone Mountain as a site for operating fly traps to determine if these rarer species could be collected in this manner. Thirtyfour trap collections were made about the base and upon the sides of the mountain from April 14 to May 31, 1952. These collections yielded over 21,000 flies, of which nearly 1,100 were sarcophagids and only 11 males and 20 females were considered to represent uncommon species. On May 2, while one of the writers set traps the other climbed to the summit of Stone Mountain and in a 60-minute period collected 31 sarcophagids, of which 29 were males of uncommon species. This is equivalent to 29 specimens of uncommon species per man-hour, compared with 0.076 such flies per trap-hour. Another expression is that 85 percent of the netted flies and only 0.14 percent of the trapped flies were unusual sarcophagids. With this initial discovery, trapping in the vicinity of the mountain was abandoned, and the summit of Stone Mountain was visited 13 times in May and June. Other summits were also visited on one or more occasions, beginning with the following dates: Kennesaw Mountain, June 12; Rabun Bald, June 20; and Mount Enotah, July 13. In addition, seven other summits in northern Georgia. were visited a total of nine times during July and August. By late June, collecting at Stone and Kennesaw Mountains had become unprofitable, probably due to extreme drought conditions, so there are practically no records from these mountains during July and August. In the environs of Rabun Bald and Mt. Enotah, some rainfall occurred, and collecting was concentrated there during this period. In the fall, collecting was continued on Stone and Kennesaw Mountains, Rabun Bald, and Mount Enotah, at two to four week intervals until the last week of October. Prior to late June, traps were set out overnight, but often most of the collections were destroyed by ants, the baits were stolen by mammals, or the traps were otherwise disturbed. By early July, it was decided to make trap collections during the same period that net collections were made. It was extremely useful, for purpose of comparing and evaluating the results of the two modes of sampling fly populations, to have the collection periods coincide. This paper contains a comparison of the collections made by net and by baited trap on mountain tops in Georgia during 1952. Collecting was continued in the spring of 1953 to complete records for a full year. This paper is considered to be a preliminary report, since the 1953 data have not been tabulated and indentifications of the 1952 specimens have not been completed. A final report awaits the completion of this work and the description of the new species.
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