The bioturbation of Olympic marmots (Marmota olympus) and their impacts on soil properties

Abstract

Although much research has examined the characteristics of Olympic marmot behavior and habitat, most studies mention the direct bioturbation effects of these marmots incidentally in an effort to examine other phenomena. A better understanding of marmot impacts on soil properties can provide a baseline for examining additional phenomena that are influenced by marmot activity. Soil surface and subsurface temperature, compaction, and moisture were measured in situ on abandoned marmot burrows in northeastern Olympic National Park, Washington. Soil samples were collected to analyze texture, pH, salinity, P, K, and organic matter content. Results indicated that soil compaction and organic matter were significantly reduced on abandoned marmot burrows when compared to undisturbed sites. Surface temperatures were typically warmer on marmot-disturbed soils, and subsurface temperatures were cooler. Soil moisture, texture, pH, salinity, and macronutrients were surprisingly similar on both disturbed and undisturbed soils. Findings suggest that Olympic marmots affect both physical and chemical soil characteristics, but additional research will be needed to evaluate the duration and extent of their impacts.

Keywords:

• Olympic marmot
• bioturbation
• ecosystem engineering
• zoogeomorphology
• pedobioturbation

Acknowledgements

Thanks to the personnel at Olympic National Park, Washington for allowing access to the park. Dr Sue Cox-Griffin is thanked for sharing location data of burrows.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

This work was partially supported by the Sandra E. Estaville Dissertation Research Scholarship, Department of Geography, Texas State University.