The biting habits of Leptoconops bequaerti. I. Methods; standardization of technique; preferences for individuals, limbs and positions.
Abstract
The following is based partly on the authors' summary. As adhesive traps have been ineffective in providing estimates of populations of biting flies in Jamaica and light-traps are difficult and expensive to operate, a detailed study was made near Falmouth of the biting habits of Jamaican Ceratopogonids [cf. RAE B 57 453, 609] in order to develop a standardised quantitative technique for measuring their biting rates, suitable for use in the study of both circadian and seasonal cycles of abundance. Studies made on Leptoconops becquaerti (Kieff.) are described in this paper. Catching periods were of 15 min. separated by 5-min. intervals [cf. 57 453], Data were obtained from two experiments carried out in October and December 1959 to standardise techniques (one at Florida beach where catches were carried out during four or eight periods starting 80 minutes after dawn and the other at White Bay with catches just before sunset) and from 19 regular weekly catches, each of three periods, starting 40-60 minutes after dawn on Florida beach between February and July 1960 and four 24-hour trials in January 1960 on Florida beach, in which the techniques were applied. Four men made catches from an exposed limb, and a fifth made meteorological readings. The methods used and the analysis and presentation of the data are described in detail. Females of L. becquaerti were taken four times as often on the leg as on the arm. In a comparison between the collectors, two (K and L), who were both light-skinned, were equally attractive and caught about 30% more than a third (C), who was dark-skinned. All three caught significantly more than the fourth (S), who was also dark-skinned. L. becquaerti was equally abundant in each of the four positions at both sites. Correction factors for limbs and collectors are given for use in other experiments. The findings for L. becquaerti are compared with observations on Culicoides barbosai Wirth & Blanton [57 453] and C. furens (Poey) [57 609].