Muhigwa J B, Saini R K, Hassanali A
International Centre for Insect Physiology and Ecology, Nairobi, Kenya.
J Med Entomol. 1998 Mar;35(2):148-52. doi: 10.1093/jmedent/35.2.148.
The effect of fly abundance on the catch index of traps and that of rain as a source of variation in fly abundance were investigated for Glossina fuscipes fuscipes Newstead around Lake Victoria, western Kenya, using odor-baited and color-improved traps. There was a significant inverse relationship between the catch index of experimental traps and abundance of flies; the catch index being the ratio of catch in the experimental trap per catch in a reference trap. At low tsetse abundance (< 10 flies per trap per day) there was a 3-fold increase of the catch of females in the experimental trap compared with the control. Rainfall alone explained 22-87% of the total variation of fly abundance. It is suggested that fly abundance should be considered in evaluating baits for G. f. fuscipes or when using traps for monitoring. The relative depression of the catch index at high abundance may be related to avoidance of conspecifics. Flies entered standard traps in an inverse proportion to the number observed at the trap. Females approached traps in greater numbers when fewer decoys (dead flies) were placed on traps.
在肯尼亚西部维多利亚湖周边，使用气味诱饵和改良颜色的诱捕器，研究了苍蝇数量对诱捕器捕获指数的影响，以及降雨作为苍蝇数量变化来源的影响。实验诱捕器的捕获指数与苍蝇数量之间存在显著的负相关关系；捕获指数是实验诱捕器捕获量与参考诱捕器捕获量的比值。在采采蝇数量较低时（每天每个诱捕器少于10只苍蝇），与对照组相比，实验诱捕器中雌性采采蝇的捕获量增加了3倍。仅降雨就解释了苍蝇数量总变化的22%至87%。建议在评估fuscipes fuscipes诱饵或使用诱捕器进行监测时，应考虑苍蝇数量。在高数量时捕获指数的相对降低可能与避免同种个体有关。苍蝇进入标准诱捕器的比例与在诱捕器处观察到的数量成反比。当诱捕器上放置的诱饵（死苍蝇）较少时，雌性苍蝇接近诱捕器的数量更多。
