Anthropogenic drivers of gypsy moth spread

Abstract

The gypsy moth, Lymantria dispar (L.), is a polyphagous defoliator introduced to Medford, Massachusetts in 1869. It has spread to over 860,000 km 2 in North America, but this still only represents of its susceptible host range in the United States. To delay defoliation in the remaining susceptible host range, the government maintains a barrier zone and a quarantine, reflecting a presumption that anthropogenic factors are important in the spread of gypsy moth. We develop a model framework that relates these factors along with biophysical characteristics to a county's susceptibility to gypsy moth invasion. We then compile a dataset for counties within 200 km of the infested area and use trap catch data from 1999 to 2007 to estimate the probability of gypsy moth presence. As expected, gypsy moth is more likely to be found close to the population front and to traps that recorded moths in the previous year. However, when controlling for these factors, our most robust finding is that the use of wood for home heating and energy is consistently positively correlated with the presence of gypsy moth. In contrast, the movement of wood products by industry, which is actively regulated by state and federal governments, is rarely correlated with the presence of gypsy moth. This is consistent with effective regulation of the movement of goods by industry, but not by the public. Our findings provide empirical support for the importance and challenge of firewood as a vector for non-native forest insects.

The Speed of Invasion: Rates of Spread for Thirteen Exotic Forest Insects and Diseases

“…In this analysis, new infestations were included regardless of the mode of transmission and consequently the estimates include human facilitated movement. Recent work has highlighted the importance of human facilitated movement, such as spread of infested firewood, particularly in long-distance dispersal [63,64].…”

Identification of invasion status using a habitat invasibility assessment model: The case of Prosopis species in the dry zone of Myanmar

“…Spatial zoning of invasion status based on a habitat invasibility assessment model is useful for planning the management of invasive species (Bigsby et al, 2011). Our study suggests that Prosopis invasions will continue to increase in the central dry zone of Myanmar unless propagule control measures are initiated soon.…”

Alien Species and Insect Conservation

“…However, it still occupies only about a quarter of its possibly susceptible range there (Bigsby et al 2011 ). The Gypsy moth ( Lymantria dispar , Lymantriidae) has spread widely in North America since it was introduced in 1869, and has become one of the region's most important forestry pests.…”