William R. Clark Marsha A. Sovada A.S. Wiewel 2007 <p><span>We compared track-tube sampling with mark–recapture livetrapping and evaluated a track-tube index, defined as the number of track tubes with identifiable small mammal tracks during a 4-night period, as a predictor of small mammal abundance estimates in North Dakota grasslands. Meadow voles (</span><i>Microtus pennsylvanicus</i><span>) were the most commonly recorded species by both methods, but were underrepresented in track-tube sampling, whereas 13-lined ground squirrels (</span><i>Spermophilus tridecemlineatus</i><span>) and Franklin's ground squirrels (</span><i>S. franklinii</i><span>) were overrepresented in track-tube sampling. Estimates of average species richness were lower from track tubes than from livetrapping. Regression models revealed that the track-tube index was at best a moderately good predictor of small mammal population estimates because both the form (linear versus curvilinear) and slope of the relationship varied between years. In addition, 95% prediction intervals indicated low precision when predicting population estimates from new track-tube index observations. Track tubes required less time and expense than mark–recapture and eliminated handling of small mammals. Using track tubes along with mark–recapture in a double sampling for regression framework would have potential value when attempting to estimate abundance of small mammals over large areas.</span></p> application/pdf 10.1644/06-MAMM-A-098R1.1 en Oxford Assessing small mammal abundance with track-tube indices and mark-recapture population estimates article