Abstract It has been shown that rodent extermination measures are most effective when carried out throughout an entire affected area, mainly during the calendar period that coincides with the diapause in reproduction. Efforts aimed at reducing a rodent population to an acceptable size must be proportional to how effectively the rodents resist damaging factors. There is a positive correlation between population complexity and resistance, which means that as many independent methods as possible must be devised to combat the main groups within the structure. The number of methods may be rigorously defined if the target groups have been identified. For each targeted (discriminatory) extermination method, we can expect rodents to exhibit a specialized adaptive mechanism, whereas we can expect a less specialized one for each nondiscriminatory method. The probability of reducing the number of synanthropic rodents at a controlled site is proportional to the effectiveness of the product and the vulnerability indicators of the population. The probability that the size of a synanthropic rodent population will be restored at a controlled site is proportional to the size of the living environment, the increase in population due to reproduction and immigration, and the rate at which reproductive groups are formed. It is inversely proportional to the size of the living environment at neighboring sites as well as the distance between the controlled facility and neighboring populated sites. Stable habitats are associated with more predictable results of extermination efforts.
Key Words Synanthropic rodents populations, independent extermination methods, target groups, restoration of number, size of the living environment