Prairie dogs are keystone species that impact both animals and plants in grassland habitats. They are a food resource for secondary consumers such as badgers, foxes, and raptors. Also, the mounds that they construct are home to many arthropod and reptile species that otherwise might not survive in grasslands. Both Gunnison’s and black-tailed prairie dogs can increase the number of plant species in grasslands and landscape heterogeneity with their ecosystem engineering that creates disturbed patches on the landscape. Gunnison’s prairie dogs, which were native herbivores at the Sevilleta National Wildlife Refuge (NWR) before their populations disappeared, were reintroduced at the Sevilleta NWR in 1997, 2005, and 2008. In 1998, a Gunnison’s prairie dog colony naturally established along the northern border on the east side of the Refuge. The naturally occurring colony and the colony that was reintroduced in 1997 have since then severely declined or gone locally extinct. Still, with the removal of cattle from the Sevilleta in 1973, the reintroductions of Gunnison’s prairie dogs in 2005 and 2008 provides an interesting opportunity to study how a native keystone herbivore affects a grassland habitat without the pressures and competition from livestock.
Three psuedo-replicates in a paired plot design: 1)plots where prairie dogs have been reintroduced and 2)control plots.Sampling Design
Each 100 x 100m plot contains 36 sample units (quads) that are 20m apart in a 6 x 6 grid. These quads are numbered in a zig zag pattern starting in the NE corner of the plot where the first six quads go north to south, the next six plots that are west of the first quads go south to north, and so on for the remaining quads on the plot. These quads are marked by a numbered rebar stake.Field/laboratory Procedures
A 50 x 50 cm quadrat separated into twenty-five 10 x 10 cm squares are placed southeast of a small white pvc pipe that marks permanent subplots. Then, percent covers and highest height are estimated for each plant species into palmtop computers. Species occupying less than 1%, a quarter of a 10 x 10 cm square, are recorded 0.1 %. When estimating plant species percent covers yellow and green plant material are included in the measurement. Individual plants that are completely gray, containing no yellow or green foliage, are not assessed in the percent cover estimate. For highest height, the ‘average’ height of the foliage for perennialspecies is recorded and for annual plant species the height to the top of the inflorescence, flowers and fruits,is recorded. The estimate of percent cover of disturbance from prairie dogs is the same as the plant cover estimates. Finally, all prairie dog fecal pellets that are in the quadrat, subplot, are counted.
Data were qa/qced and obvious errors were corrected. A column for height was added to the data since we added to the protocol a height measurement in 2009. We also added in 2008 prairie dog fecal counts and in 2009 prairie dog disturbance measurements. Previous data were explored to renter past height measurements along with adding disturbance and prairie dog fecal pellet counts to the data. These measurements were not recorded for all years. 11 January 2010 tlk
More information about who is involved with the samples/data: Mike Friggens 1999-September 2001Karen Wetherill February 7, 2000-Augst 2009Terri Koontz February 2000-August 2003 August 2006-PresentShana Pennington February 2000-August 2000Heather Simpson August 2000-August 2002Chris Roberts September 2001-August 2002Caleb Hickman September 9, 2002-November 15, 2004Seth Munson September 9, 2002-June 2004Maya Kapoor August 9, 2003-January 21, 2005 March 2010-March 2011Tessa Edelen August 15, 2004-August 15, 2005Charity Hall January 31, 2005-January 3, 2006Yang Xia January 31, 2005-PresentMichell Thomey September 3, 2005-August 2008Jay McLeod January 2006-August 2006Amaris Swann August 25, 2008-Jan 2013John Mulhouse August 2009-PresentAmanda Boutz August 2009-May 2010Stephanie Baker October 2010-PresentMegan McClung April 2013-Present
Additional Study Area Information
Study Area Name: Prairie Dog Town
Study Area Location: The study area is about 655 ha (~2.5 sq mi) in size and approximately1 km due west from the foothills of the Los Pinos Mountains. The study is also just north of the Blue Grama Core Site.Elevation: 1670 mSoils: sandy loam and sandy clay loamSite history: historically large prairie dog colonies inhabited the study area