Destruction of Habitat. Movement may occur during construction. As habitat is destroyed, the millipedes will seek other sites. After long periods of rain, standing water may force millipedes from low lying areas. Although any of the above may be involved, population pressure is probably the main reason for mass movements of millipedes.
Movement is always at night.
A person may clean up in the afternoon and by the next morning hundreds have again accumulated. They may enter though weep holes, around service lines or around loose fitting windows or doors. Once they enter the house, they will soon die due to the dry conditions which occur in most air conditioned buildings. Although there may some odor associated with these animals, the number one problem is probably one of nuisance B just the thought of thousands of anything occurring on ones property is somewhat unsettling. In one case, a family had been living at a location south of Tupelo for seven to eight years and had never seen a millipede, much less several thousand a night.