Small mammal monitoring protocol for the Central Alaska Network: Protocol narrative version 1.0

Flamme, Melane; Schmidt, Joshua; MacCluskie, Maggie; Miller, Scott

The National Park Service (NPS) has developed a long-term ecological monitoring program known as “Vital Signs Monitoring” to provide the minimum infrastructure and enable more than 270 national park units, organized into 32 networks nationwide, to identify and implement long-term monitoring of their highest-priority indicators of natural resource condition. The Vital Signs Monitoring Program is a major component of the National Park Service’s strategy to improve park management through greater reliance on scientific information. This protocol details the justification and procedures for Small Mammal monitoring, a Vital Sign selected by the Central Alaska Network (CAKN). The CAKN includes three park units in interior Alaska: Denali National Park and Preserve (DENA), Yukon-Charley Rivers National Preserve (YUCH) and Wrangell-St. Elias National Park and Preserve (WRST) (Figure 1). The CAKN developed its monitoring program to encompass several trophic levels of park ecosystems so that the program would be as robust as possible to detecting change constituent vital signs (MacCluskie and Oakley 2005). Small mammals, including voles of the genera Microtus and Myodes (formerly Clethrionomys), are useful for long-term monitoring because they consume seeds, fungi and invertebrates, provide a key prey resource for raptors and carnivorous mammals, and play an important ecological role by having the ability to influence species above and below them in the food chain (Boonstra et al. 2001; Boutin et al. 2001). While they are not highly visible in the boreal forest, their collective biomass contributes a larger proportion to the animal community than that of grizzly bears (Boonstra et al. 2001). Consequently, changes in the abundance or density of small mammals may subsequently affect the species that prey upon them. From these data and other studies, we know that population dynamics of small mammals vary across latitudes. Additionally, the relative abundance of small mammal species is directly related to local composition of plant species. Thus, any park-wide changes in weather or plant species composition or primary productivity will likely affect small-mammal distribution and patterns of abundance (Bangs 1984; Hornfeldt et al. 1986; Carrier and Krebs 2002; Olofsson et al. 2012; Schmidt et al. 2017). The objective of CAKN Small Mammal monitoring project is to: Document long-term trends in small mammal population dynamics on the DENA Rock Creek legacy plots, including temporal patterns of density and abundance, of three target species of voles, Myodes (formerly Clethrionomys) rutilus, Microtus oeconomus and Microtus miurus. The population dynamics of small mammals can be feasibly estimated by small field crews using basic equipment and traveling on foot (Rexstad 1996). Life history characteristics of small mammals, including short life spans, high reproductive rates, and forays of less than 2 miles (4km), cause population numbers to be reflective of local conditions. The combination of these circumstances makes small mammal populations useful for monitoring to detect local changes in boreal ecosystems (Rexstad and Debevec 2008). Small mammal populations, including the target species of voles (northern red-backed vole, Myodes [formerly Clethrionomys] rutilus, tundra vole, Microtus oeconomus, and singing vole, Microtus miurus) are monitored annually in DENA at the Rock Creek legacy plots using mark-recapture methods via live-trapping techniques. The Small Mammal monitoring protocol consists of a narrative (this document), Data Quality Standards and Standard Operating Procedures (SOPs) that outline specific aspects of the monitoring protocol.

Small mammal monitoring protocol for the Central Alaska Network: Protocol narrative version 1.0

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