Landscape Factors Associated with Subterranean Termite (Isoptera: Rhinotermitidae) Treatments and Colony Structure in Residential Subdivisions

摘要

Subterranean termites (Isoptera: Reticulitermes ) are common structural pests, but it is not well known how landscape factors are associated with urban colonization. This study examined patterns of subterranean termite colonization in 13 mid-Missouri residential subdivisions. Ten- and 20-year-old homes built on historically agricultural and forested landscapes were inspected for treatment by termiticide application or bait stations. Contemporary and historical aerial imagery were analyzed using GIS software, and patterns of colonization were compared among subdivisions. The genetic structure of termite colonies collected in undeveloped landscapes and residential subdivisions was compared using microsatellite DNA. Twenty-year-old subdivisions had significantly higher treatment proportions than 10-year-old subdivisions. At year 10, historically forested subdivisions had a higher treatment proportion than historically agricultural subdivisions. By year 20, there was no significant difference in treatment proportion between historical landscape types, indicating that subdivisions built on agricultural landscapes eventually catch up to subdivisions built on forest landscapes. Although there was not strong statistical support, treated homes in historically agricultural subdivisions tended to be close to forest patches, but there was less of an association in historically forested subdivisions. Colonies in undeveloped landscapes were more inbred compared to colonies in residential subdivisions, indicating that colonies sampled in subdivisions had fewer secondary reproductive and were potentially younger than those sampled in undeveloped landscapes. This study provides some correlative support for the role of dispersing alates as urban colonizers, because treatments were often located at relatively long distances from undisturbed forest patches in historically agricultural subdivisions.