Impact of climate change on the small mammal community of the Yukon boreal forest

Abstract

Long‐term monitoring is critical to determine the stability and sustainability of wildlife populations, and if change has occurred, why. We have followed population density changes in the small mammal community in the boreal forest of the southern Yukon for 46 years with density estimates by live trapping on 3–5 unmanipulated grids in spring and autumn. This community consists of 10 species and was responsible for 9% of the energy flow in the herbivore component of this ecosystem from 1986 to 1996, but this increased to 38% from 2003 to 2014. Small mammals, although small in size, are large in the transfer of energy from plants to predators and decomposers. Four species form the bulk of the biomass. There was a shift in the dominant species from the 1970s to the 2000s, with Myodes rutilus increasing in relative abundance by 22% and Peromyscus maniculatus decreasing by 22%. From 2007 to 2018, Myodes comprised 63% of the catch, Peromyscus 20%, and Microtus species 17%. Possible causes of these changes involve climate change, which is increasing primary production in this boreal forest, and an associated increase in the abundance of 3 rodent predators, marten (Martes americana), ermine (Mustela ermine) and coyotes (Canis latrans). Following and understanding these and potential future changes will require long‐term monitoring studies on a large scale to measure metapopulation dynamics. The small mammal community in northern Canada is being affected by climate change and cannot remain stable. Changes will be critically dependent on food–web interactions that are species‐specific.

Bilberry seed production explains spatiotemporal synchronicity in bank vole population fluctuations in Norway

“…There is no doubt that predators affect prey abundance, but in our view, their contribution is most likely to enhance or dampen population cycles, depending on type of predator (specialist or generalist) and the availability of alternative prey. Temporal asynchrony in the fluctuation pattern of sympatric rodent species is not unusual (Framstad, 2020; Hörnfeldt, 1994; Krebs, Boonstra, Gilbert, Kenney, & Boutin, 2019; Selås, 2020), a pattern not in accordance with the specialist predation hypothesis. Also the fact that rodent cycles exist in the absence of small mustelids (Graham & Lambin, 2002; Krebs et al, 2002; Menyushina, Ehrich, Henden, Ims, & Ovsyanikov, 2012) refutes predation as a universal explanation (Oli, 2019).…”

Rodent management and cereal production in Asia: Balancing food security and conservation

“…As well as potential socio‐political opposition to the environmental release of gene drive technology to manage rodent pests, another essential consideration is how will wild rodent populations in agricultural landscapes respond to new methods of control. Will all species respond the same? Climate change: A 46‐year study of small mammal populations in the Boreal forest in northern Canada indicates that there have been long term shifts in the relative abundance of the four main species and marked changes in the energy flow in the herbivore populations contributed by the small mammals, and that these may be related to changes in the climate 109 . Unfortunately, we do not have long term monitoring of rodent populations in agricultural systems in Asia to assess effects of climate change at this level.…”

“…Climate change: A 46‐year study of small mammal populations in the Boreal forest in northern Canada indicates that there have been long term shifts in the relative abundance of the four main species and marked changes in the energy flow in the herbivore populations contributed by the small mammals, and that these may be related to changes in the climate 109 . Unfortunately, we do not have long term monitoring of rodent populations in agricultural systems in Asia to assess effects of climate change at this level.…”

Timing outweighs magnitude of rainfall in shaping population dynamics of a small mammal species in steppe grassland

“…The global surface air temperature has increased by about 1° during the past century and is projected to exceed 1.5 to 2 °C by the end of the 21st century ( 1 ). Climate change has caused profound impacts on the Earth’s ecosystems, such as local extinctions ( 2 ), range shifts ( 3 ), and population fluctuations ( 4 , 5 ) of many species. Many organisms have advanced the timing of phenological events in response to climate warming, such as earlier leaf-out in plants, earlier emergence of insects, or accelerated egg hatching dates for birds ( 6 ).…”