Intermountain journal of sciences : IJS最新文献

We examined the influence of rock cover, as an indicator of presumable retreat site availability on the abundance of deer mice (Peromyscus maniculatus) and prevalence of Sin Nombre virus (SNV) using long-term live trapping and habitat data from three live trapping grids and a short-term (three month), spatially replicated study across three slopes in Cascade County, Montana. In our long-term study, we found that deer mice were more abundant at a live-trapping grid with greater rock cover, than two grids with less rock cover. There was a non-significant trend(P = 0.053) for deer mice to be more abundant in rocky sites in the short term study. In the long-term study, average SNV antibody prevalence among deer mice was slightly greater (5.0 vs. 3.5 % on average) at the live trapping grid with more rock cover, than the grid with less rock cover. We were unable to demonstrate differences in SNV antibody prevalence among treatments in the short-term study. Further studies are needed to elucidate the multiple determinants of deer mouse abundance and SNV prevalence in grassland ecosystem and other habitat types.

We examined the effects of grazing on deer mouse (Peromyscus maniculatus) movements into buildings using passive integrated transponder (PIT) technology and small simulated buildings located on 0.6-ha treatment (grazing) and control (no grazing) plots. Twelve experimental 9-day trials were conducted over the course of the study. During these trials, mouse movements into buildings were monitored during three time periods (each 3 days in length). In the treatment plots these time periods corresponded to pre-grazing, grazing, and post grazing by horses. The number of individual deer mice entering buildings over time decreased in both the grazed and control plots during the 9 days of each experiment. The number of entrances per/individual among the pre-grazing, grazing and post grazing periods was different between control and treated plots for both males and females. The distribution of entrances/individual among the three periods differed between males and females in both grazed and control plots. The habitat modification caused by grazing appeared to reduce deer mouse activity (entrances/individual) in buildings but does not affect the number of mice entering buildings. Reducing vegetative cover by grazing or mowing may not affect the number of mice investigating small structures but grazing creates different activity patterns in the structures for neighboring deer mice.

Deer mice (Peromyscus maniculatus) are the principal reservoir host of Sin Nombre virus (SNV). Deer mice use a wide variety of habitats including peridomestic settings in and around human dwellings, their presence in and around homes has been implicated as a risk factor for acquiring Hantavirus Pulmonary Syndrome. Deer mice are believed to enter buildings in order to gain access to a variety of resources including food, bedding material, and better thermal microclimates. However, no one has experimentally tested which factors influence mice use of buildings. We conducted experiments using small simulated buildings to determine the effects of two factors, i.e., food and bedding material, on mouse activity in these buildings. We also examined if these effects varied with time of year. We found that deer mice entered our buildings regardless of the presence or absence of food or bedding. However, the amount of activity in buildings was affected by what they contained. We found significantly higher indices of activity in buildings containing food compared to both empty buildings (control) and buildings containing bedding material. Time of year did not affect activity in buildings.