Study ID 357

Small Mammal Trapping Webs on the Central Plains Experimental Range

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Realm: Terrestrial
Climate: Temperate
Biome: Temperate grasslands, savannas and shrublands
Central latitude: 40.828890
Central longitude: -104.758200
Duration: 13 years, from 1994 to 2006

1104 records

10 distinct species

Across the time series Onychomys leucogaster is the most frequently occurring species


Stapp, P. (2013) SGS-LTER Long-Term Monitoring Project: Small Mammals on Trapping Webs on the Central Plains Experimental Range, Nunn, Colorado, USA 1994 -2006, ARS Study Number 118. Environmental Data Initiative. Available at:, accessed 2017.


In 1994 we implemented a sampling scheme to monitor long-term changes in relative abundance of small mammals in representative habitats of shortgrass steppe. We live-trapped nocturnal rodents twice each year (spring late summer) on trapping webs in upland prairie (GRASS) and saltbush-dominated (SHRUB) habitats. Three 3.14-ha webs were established in each habitat. Each web had 124 Sherman traps which were spaced 10-m apart on 12 100-m spokes with 30 degrees between spokes. Four traps were set in the center of the web. Traps were set for four consecutive nights in each trapping session. Traps are baited with a mix of peanut butter and oats set in the evening and checked (and closed) at dawn. We recorded sex age and weight upon first capture of all individuals. In the early years of the study individuals were batch-marked (Sharpie colored felt markers) to distinguish recaptures from new individuals providing the minimum information necessary to use distance-sampling methods to estimate density. Most nocturnal species are now usually marked with aluminum ear tags although we continue to mark very small (pocket mice) or small-eared (voles) species only with felt pens. For ear-tagged animals we distinguish new captures (N) from individuals marked during previous sessions (old O) versus those that are recaptured (R) on 2nd 3rd or 4th nights of a trapping session. The location of one trapping web was changed from 13NE (1994-1997) to 13SW (1998- present) because of concerns about intensive cattle use in the pasture as well as activity of CPER Site Manager?s cats. bird abundance calculated from annual censuses on 4 similar transects and bird abundance per km^2 exprapolated from these counts Unit of abundance = IndCountInt, Unit of biomass = NA