The proper adjustment of temperature and/or ambient humidity can be effective against pests. However, dead remains will still be present, polluting the area, and must be removed.
This form of control is mainly useful against arthropods (insects, etc.). In contrast, rodents have the ability to adapt rapidly in a greater range of temperature variations maintaining their homeostasis. Their decomposition may cause an additional problem to the infested area, complicating the use of this method.
Traps are effective in reducing the levels of pest population, although complete elimination is unlikely to be achieved.
Additionally, traps are used in surveys for sampling and pest identification, as well as for determining the extent, degree and sometimes source of infestation. They may also be used for biomonitoring premises to determine if or when a problem arises.
In the case of arthropods, such as cockroaches and stored product insects, traps are used almost solely for biomonitoring purposes. For combating house flies in particular, electric fly killers combined with glue traps give satisfactory results.
For rodents, traps can be very useful under the following circumstances:
in large infestations, as an initial stage of control
in places where rodenticides are not appropriate or not allowed such as food preparation areas
when a fast and effective control method is needed such as the control of accidental rodent intruders (e.g. through an open door)
However, if traps are used extensively, after the death of a few rodents, ‘trap shyness’ may develop. This does not apply to insects, which do not display such learning behaviour.
Traps are positioned at appropriate points and checked frequently whilst trapped pests are disposed of. Particular attention is paid to rodent traps, where based on legislation and moral ethics, they should be checked frequently for avoidance of suffering.
There are several types of traps, the most common being mechanical for live catching or killing, glue traps, electronic fly killers, etc. Most traps use attractants such as light, colour, food, odour, carbon dioxide (CO2) and pheromones.