Details of this species in Colorado Status: Not specified
Invasiveness: Invasive
Occurrence: Established
Source: Seery et al. 2003; Collinge et al. 2005 Arrival Date:
Introduction: Unknown Species Notes for this Location:
Management Notes for this Location:
Seery et al. (2003) tested the effectiveness of deltamethrin, a synthetic pyrethroid similar to permethrin. Deltadust was found to significantly reduce flea populations within prairie dog burrows and on the animals themselves. It also had a significant residual effect, with flea populations at non-detectable levels after 84 days. Furthermore, Deltadust seemed to suppress an epizootic of plague at another area on Rocky Mountain Arsenal during the summer of 2000. There were no losses of prairie dogs on the treated colonies, while populations were decimated in the adjacent untreated colonies. The authors conclude that Deltadust is an effective insecticide for control of flea populations in prairie dog colonies, and is an important tool for managing plague epizootics in these animals (Seery et al. 2003).A number of authors have proposed a trophic-cascade hypothesis for human plague that hypothesizes high precipitation increases plant productivity, which increases rodent and flea populations 1-2 years later. Increased rodent populations lead to higher contact rates between host and vector and higher rates of transmission to humans (e.g. Enscore et al. 2002 in Collinge et al. 2005). Collinge et al investigated whether this trophic cascade model fitted for prairie dog populations in Montana and Colorado. They found evidence in support of the temperature-modulated trophic-cascade hypothesis for plague occurrence in the Montana study area, but no evidence supporting this hypothesis in Colorado. However this may be due to a lack of data or differences in landscape features that affect plague transmission. Plague in prairie dogs has previously been considered highly unpredictable in space and time. However models produced by Collinge and colleagues (2005) that relate climate and plague occurrence in the Montana study area suggest that it may be possible, with further research, to reveal strong relationships between climate and plague occurrence and make predictions about patterns of plague occurrence in certain areas. In areas where climate in more variable, such as Colorado, other factors may better predict plague occurrence in prairie dogs (Collinge et al. 2005). Impacts:
Pathogenic: At Rocky Mountain Arsenal National Wildlife Refuge, plague epizootics causing 95-99% prairie dog mortality have been documented since the mid-1970s, affecting as little as a few hectares to large scale epizootics of 1,000 ha (United States Fish and Wildlife Service, unpublished data in Seery et al. 2003). Prairie dogs are considered a high priority species in this prairie ecosystem as they provide a prey base for a variety of predators in the ecosystem as well as habitat infrastructure to burrowing owls and mountain plovers through their burrowing activities Last Modified: 19/02/2010 2:39:33 p.m.
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