Home range variability, spatial aggregation, and excursions of Akodon azarae and Oligoryzomys flavescens in Pampean agroecosystems

Abstract

Rodents are reservoirs of various types of hantavirus, some of which are agents of hantavirus pulmonary syndrome in humans. Each hantavirus is associated with a single rodent host species but successive spill‐over events may eventually lead to host‐switching and new species’ becoming host of a given pathogen. This study aims to gain an understanding of the spatial ecology of two hantavirus‐host species, Akodon azarae, and Oligoryzomys flavescens, by identifying factors modulating their home range sizes and stability, and by evaluating intra‐ and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in sympatry. For this, eleven capture‐mark‐recapture surveys were carried out, spanning 22 months. We found that A. azarae males have larger and more mobile home ranges than females, independently of the season. Consequently, males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the environment. Contrasting, O. flavescens individuals showed negligible displacements of their home range through time, which could limit the range of hantavirus spread in host populations. Since O. flavescens is host to Lechiguanas hantavirus (pathogenic to humans) this result encompasses epidemiological relevance, for it may imply the existence of local foci of infection. Additionally, individuals of both species performed excursions outside their home ranges. These events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non‐infected rodent populations, favoring the persistence of the virus in nature.

Variations in home range and core area of red-backed voles (Myodes regulus) in response to various ecological factors

“…In contrast with the home range, given that small rodents must consistently gather food in preparation for the winter 50 , 53 , M. regulus appeared to occupy a broad core area to improve its odds of findings adequate food sources within regions with a high density of conspecifics. The home range and core of male voles were wider than those of females, which was consistent with the findings of previous studies 1 , 54 . In breeding season, Myodes species show differences in spatial distributions between male and female because of different reproductive strategies between sex 4 .…”

“…Knowledge of animal distribution is crucial for the management of invasive and endemic species and disease transmission within various ecosystems 1 , 2 . The distribution of wildlife is largely determined by the responses available in a given area, with individuals favoring locations where they can find food, shelter, nesting grounds, and mates 3 .…”

Modelling relative abundance of Oligoryzomys flavescens, an Orthohantavirus reservoir, in an endemic hantavirus pulmonary syndrome zone

“…In Buenos Aires, O. flavescens is a ubiquitous mouse that is present throughout almost all the province with the exception of its southernmost area (Gómez Villafañe et al, 2019). Though much has been studied about the ecology of this species in some particular sites (Busch & Kravetz, 1992;Gorosito et al, 2020;Maroli et al, 2018;Maroli et al, 2020;Mills et al, 1992;Muschetto et al, 2018), and there have been some insights on the variations in the structure of rodent assemblages in the region (González Fischer et al, 2012, its abundance and habitat associations throughout its distributional area are not well known. As well as for other cricetid rodents of the region, its abundance has been associated with environmental and climatic factors such as precipitation, temperature, land use and tree cover (Andreo et al, 2009;Fraschina et al, 2012;González Fischer et al, 2012;Vadell & Gómez Villafañe, 2016;Vadell et al, 2017;Maroli et al, 2021).…”