Tropical African ticks are found on their hosts throughout the year, but at varying infestation levels. These population changes, for most of the time, have been associated with climatic changes. Their development is inversely related to temperature. Several workers reported that development failed for a number of tick species at temperatures below 15°C, suggesting a possible lower temperature threshold for tick development. The upper development limit for most of the tropical rhipicephalids appear to be 37°C.
Ticks are particularly susceptible to attack during lethargic pre-moulting and the weak post-moulting period. Many biological features enable them, however, to survive especially well. They lay numerous eggs and withstand a comparatively wide temperature and humidity range with greater ease. They survive for months or years without food.
Their degree of host specificity varies from genus to genus or within subgroups of various genera. The requirement of two or more kinds of hosts often with divergent habits, limits their distribution to certain faunal areas.
This paper reviews our current knowledge on development and survival of ixodid ticks under tropical field conditions including some laboratory studies.