Experiments on overwintering and subsequent survival of adult Tribolium castaneum were carried out in a metal shed located in the National Food Research Institute, Tsukuba, Ibaraki, Japan. T. castaneum adults reared at 30°C were used in the study. Two experimental conditions were tested: with and without water supplement. The survival curves for the two conditions were the same. Overwinter survival rates of adults were 10% or less at the first year and 50% or more at the second year for both conditions. Offspring were observed even after the second overwintering. The longest living adult died before the third winter.

The Yokohama municipal government requested the Kanagawa Pest Control Association (KPCA) to control rats in an urban area (21 ha) in Yokohama. The KPCA conducted campaigns from January 2009 to March 2011 (three years) by setting traps and warfarin block baits outside buildings. Our campaigns motivated the residents to sanitize their environment by covering rat holes with asphalt or cement, and setting planters, vending machines, or refuse containers where people used to dump trash. The average consumption of nonpoisonous block bait in 10 divisions of the area decreased from 1.51±1.19 kg in 2009 to 0.21±0.25 kg in 2011 in the pre-baiting process. The latter was significantly less (Kruskal-Wallis test, H=10.2, d.f.= 2, P<0.05). This indicated a remarkably reduced population of the Norway rat, Rattus norvegicus.

Cockroaches were collected with sticky traps in 32 places in Minato-ku, Tokyo, from July to October 2010. Cockroaches were found at 24 places (75%). Only one species, Smoky-brown cockroaches, was captured. A total of 263 individuals consisting of 31 adults (6 females, 24 males, 1 sex unknown) and 232 nymphs was captured. Nymph was the most abundant age class among Smoky-brown cockroaches (88.2%). No cockroaches were captured around planters near high-rise buildings, near doorways, or near construction sites.