small mammals

Gunnison's Prairie Dog Restoration Experiment (GPDREx): Population Dynamics within Grasslands at the Sevilleta National Widlife Refuge, New Mexico

Abstract: 

Prairie dogs (Cynomys spp.) are burrowing rodents considered to be ecosystem engineers and keystone species of the central grasslands of North America. Yet, prairie dog populations have declined by an estimated 98% throughout their historic range. This dramatic decline has resulted in the widespread loss of their important ecological role throughout this grassland system. The 92,060 ha Sevilleta NWR in central New Mexico includes more than 54,000 ha of native grassland. Gunnison’s prairie dogs (C. gunnisoni) were reported to occupy ~15,000 ha of what is now the SNWR during the 1960’s, prior to their systematic eradication. In 2010, we collaborated with local agencies and conservation organizations to restore the functional role of prairie dogs to the grassland system. Gunnison’s prairie dogs were reintroduced to a site that was occupied by prairie dogs 40 years ago.  This work is part of a larger, long-term study where we are studying the ecological effects of prairie dogs as they re-colonize the grassland ecosystem.

Data set ID: 

236

Additional Project roles: 

401

Core Areas: 

Keywords: 

Methods: 

Experimental Design

Four replicate paired 16 ha plots were established in spring 2010. Each pair consists of a treatment plot with prairie dogs (reintroduced), which are plots B and D and a control plot with no prairie dogs (plots A and C). The closest distance between adjacent plots, either within a block or between blocks, is 200 m (Figure 1). The treatment and control within each pair were randomly assigned. Each plot is a 400x400 m on 9x9 grid array with systematically located sample locations for 81 vegetation quadrats. There are also 4 more plots, E and H are control plots and F and G are treatment plots. F and G have been equipped with artificial burrows and are release sites. However, E and H were not set up to do vegetation quads.

Trapping Period

Prairie dogs will be sampled using capture-recapture methods in the summer (3rd week of June) each year and spring (last week of March) and fall when possible.

Pre-baiting Procedure

Set 150 traps within each 300m x 300m trapping area. Place traps in pairs near active burrows at least 4 days prior to trapping. At this time trap doors should be wired open (make certain all traps are properly wired open) with bait trailing from the outside into the back of (or through) the trap. Traps should be baited with sweet feed. Make sure that all traps are functioning properly by testing the trap door sensitivity and adjusting with pliers if needed. Pre-bait traps every morning for 3 days total. All pairs of traps should be numbered with one pin flag for each pair (1-75). All trap pairs should also be GPSed by their number and have maps made for ease of locating traps during trapping.

Trapping Procedures

On the morning of the first trapping day, well before sunrise, the wire should be removed from the traps and the traps then set and baited to capture animals. This can also be done the day before trapping begins. Prairie dogs should be trapped for 3 consecutive mornings.Each morning of trapping, make sure that the traps are all opened well before sunrise, so animals are not disturbed by human activity. This is very important. Traps should only be left opened during the early morning period, until about 10:00 or 11:00 am, depending on the weather conditions and time of year. Prairie dog activity declines by 10:00-11:00, so even if the weather conditions are fine for continued trapping, trap success after this time will decline. Traps should be collected by around 9:00 am, depending on the weather conditions and time of year, and all trapped animals should be brought to a common processing station. The team walks the plot to make sure and check every trap for dogs. As dogs are found trapped, a piece of masking tape is attached to the front of the trap, labeled with the trap number so that that animal can be released where it was trapped. Animals at the processing site should be kept at all times in the shade and carrots should be given to provide moisture during the heat and stress. Once animals have been processed they should be released into their burrow, at the location of their capture. All traps should then be closed for the day. To make sure all are closed, one person should close all the traps from one of the plots and mark the number on the GPS sheet to note the trap has been closed. This can also be done as a team effort, but traps need to be checked twice to make sure they are all closed.

Data sources: 

sev236_pdog_captures_20150630.txt

Gunnison's Prairie Dog Relocation Project: Population Dynamics within Grasslands at the Sevilleta National Widlife Refuge, New Mexico (2005-2014)

Abstract: 

The Sevilleta Gunnison’s Prairie Dog (Cynomys gunnisoni) Restoration project examines keystone consumer (herbivore) effects on grassland in concert with ecological restoration of a “species of greatest conservation need in New Mexico” (NMG&F Comprehensive Wildlife Conservation Strategy, 2007). SevLTER partners directly with Sevilleta National Wildlife Refuge, New Mexico Game and Fish, USFS Rocky Mountain Research Station and non-profit Prairie Dog Pals on this ambitious effort to re-establish Gunnison’s prairie dogs to blue grama dominated (Bouteloua gracilis) Great Plains grassland at the foothills of the Los Pinos Mountains on Sevilleta. While engaged in wildlife management aimed at translocation of approximately 3000 individual prairie dogs, ultimately establishing 5-6 colonies over a 500 ha area, SevLTER is focusing resources on monitoring population dynamics of reintroduced prairie dogs and their effects on vegetation production and diversity, soil disturbance and grasshopper community composition. In this experiment, prairie dogs act as the treatment on a grassland site where the species was extirpated 40 years ago. The long term nature of the project lies in the course of re-establishing prairie dogs combined with the ultimate research goal of describing the functional role of Gunnison’s prairie dogs in an arid grassland ecosystem: first we are challenged to develop and document an economical and efficient management strategy which maximizes reintroduction success and colony survival; second we are tasked with monitoring prairie dog dynamics and their effects on the grassland throughout re-establishment and into a future state, when presumably management intervention will have subsided and we characterize the ecosystem as ‘restored’ – both in the face of highly variable abiotic inputs such as precipitation and temperature and biotic impacts such as predation.

Data set ID: 

257

Core Areas: 

Keywords: 

Data sources: 

sev257_pdog_trapping_20140116

Methods: 

Sampling Period

Prairie dogs will be sampled using mark-re-sight methods in the spring (last week of March) and summer (3rd week of June) each year.  The justification for this sampling period is to understand overwinter survival and offspring recruitment.

Mark Re-sight Methodology

Prebaiting and Observation Towers

Prior to any trapping, traps in the field are checked to make sure all wooden covers are in place, if not, traps should be repaired as needed.  Set 100 traps within each 100m x 100m trapping area.  Place traps near active burrows 4 days prior to trapping.  At this time trap doors are wired open (make certain all traps are properly wired open) with bait trailing from the outside into the back of (or through) the trap. Traps are baited with sweet feed. Make sure that all traps are functioning properly by testing the trap door sensitivity and adjusting with pliers if needed. Pre-bait traps every morning for 3 sequential days total. All traps should be GPSed and have an adjacent numbered flag and tape with a corresponding number located on the trap. 

Trapping

On the morning of the fourth day, well before sunrise, the wires are removed from the traps and the traps then set and baited to capture animals. The traps are all opened well before sunrise, so animals are not disturbed by human activity.  This is very important.  Prairie dogs are trapped for 3 consecutive mornings.  Traps are only left opened during the early morning period, until about 10:00 or 11:00 am, depending on the weather conditions and time of year.  Prairie dog activity declines by 10:00-11:00, so even if the weather conditions are fine for continued trapping, trap success after this time will decline dramatically.  Traps are collected by around 9:00 am, depending on the weather conditions and time of year, and all trapped animals are brought to a common processing station. At the processing station the trap location, ear tag number, sex, weight, and age of the animal are recorded. It is indicated if the animal is new or a re-capture during this trapping period.  If no ear tags are present, new ear tags are clipped to both ears, and the numbers recorded. If one ear tag is missing, another is added to the ear with no tag, and the number recorded. All animals are marked with Nyanzol black dye.  For our purposes, it is not necessary to mark each animal with numbers.  The goal is to make sure each animal has a clear black mark on its back. Animals at the processing site are kept at all times in the shade and carrots should be given to provide moisture during the heat and stress.  Once animals have been processed they are released into their burrow, at the location of their capture. All traps are closed for the day.  To make sure all are closed, one person  closes all the traps from one of the plots and mark the number on the GPS sheet to note the trap has been closed.

Additional information: 

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 m

Soils: sandy loam and sandy clay loam

Site history: historically large prairie dog colonies inhabited the study area

Gunnison’s Prairie Dog Use of Resource Pulses in a Chihuahuan Desert Grassland at the Sevilleta National Wildlife Refuge, New Mexico: Re-sight Scan Data

Abstract: 

Seasonal environments experience cyclical or unpredictable pulses in plant growth that provide important resources for animal populations, and may affect the diversity and persistence of animal communities that utilize these resources. The timing of breeding cycles and other biological activities must be compatible with the availability of critical resources for animal species to exploit these resource pulses; failure to match animal needs with available energy can cause population declines. Adult Gunnison’s prairie dogs emerge from hibernation and breed in early spring, when plant growth is linked to cool-season precipitation and is primarily represented by the more nutritious and digestible plants that utilize the C3 photosynthetic pathway. In contrast, summer rainfall stimulates growth of less nutritious plants using the C4 photosynthetic pathway. Prairie dogs should therefore produce young during times of increased productivity from C3 plants, while pre-hibernation accumulation of body fat should rely more heavily upon C4 plants.  If seasonal availability of high-quality food sources is important to Gunnison’s prairie dog population growth, projected changes in climate that alter the intensity or timing of these resource pulses could result in loss or decline of prairie dog populations.  This project will test the hypothesis that population characteristics of Gunnison's prairie dog, an imperiled grassland herbivore, are associated with climate-based influences on pulses of plant growth.

Data set ID: 

242

Core Areas: 

Additional Project roles: 

40
41

Keywords: 

Methods: 

Gunnison’s prairie dogs will be monitored at 6 colonies, with 3 colonies each occurring with the range of prairie and montane populations. Colonies for study within the prairie populations occur at Sevilleta National Wildlife Refuge (n = 3 prairie populations) and at Vermejo Park Ranch (n = 3 montane populations).  Live-trapping of prairie dogs will be conducted during 3 periods of the active seasons—following emergence (April), after juveniles have risen to the surface (mid-to-late June), and pre-immergence (beginning in August).  Trapping will occur for 3-day periods, following pre-baiting with open traps.  At capture, sex and body mass of each individual will be recorded.  Blood and subcutaneous body fat samples will be collected nondestructively for analysis of isotopic composition.  Prairie dogs will be marked with dye, and released on site immediately following processing.  After trapping periods at each site have concluded, population counts will be conducted during 2-3 re-sighting (or recapture) periods for each prairie dog colony.  Resighting observation periods will be ~3 hours in length, and consist of 2-6 systematic scans of the entire colony, beginning and ending from marked points outside of the colony boundary.  During each observation period, prairie dogs will be counted, recorded as marked or unmarked, and location on the colony noted.  

Vegetation cover and composition measurements will be collected (or obtained at Sevilleta, where such data is already being collected) during pre- and post-monsoon periods of the active season.  Total cover will be measured by plant species (or to genus if species is indeterminable). Total cover will be measured at 12 grid points per colony using Daubenmire frames (0.5 m x 0.5 m), and at 12 grid locations 200-800 m outside of each colony boundary.  Adjacent to each Daubenmire frame, a 20 cm x 30 cm sample of vegetation will be clipped and dried for determination of volumetric moisture content of vegetation.  

Primary productivity variables (cover, moisture content) will be tested for correlations to individual and population-level condition indicators in prairie dogs.  Carbon isotope ratios (δ13C) from prairie dog blood and fat samples will be analyzed on a continuous flow isotope ratio mass spectrometer.  The relative contribution of C3 and C4 plants to the diet of each individual will be determined based upon δ13C ratios for C3 and C4 plants in the study area and a 2-endpiont mixing model, and will be calculated for each individual animal, population and season.  Population estimates will be calculated using mark-resight estimates, and compared to maximum above-ground counts.  The influence of resource pulses on prairie dog population parameters will be tested by comparing the vegetation cover, moisture content, and ratio of total C3:C4 plant cover to the ratio of C3:C4 plants in prairie dog diets, population estimates, and juvenile:adult ratios as an index to population recruitment.   

Instrumentation: 

*Instrument Name: Continuous flow isotope ratio mass spectrometer

*Manufacturer: Thermo-Finnigan IRMS  Delta Plus 

*Instrument Name: Elemental Analyzer

*Manufacturer: Costech

*Model Number: ECS4010

Additional information: 

Other Field Crew Members: Talbot, William; Duran, Ricardo; Gilbert, Eliza; Donovan, Michael; Nichols, Erv; Sevilleta LTER prairie dog field crew led by Koontz, Terri; Sevilleta NWR prairie dog field crew led by Erz, Jon.

Tissue samples are analyzed for stable carbon isotope ratios in stable isotope laboratory operated by Dr. Zachary Sharp and Dr. Nicu-Viorel Atudorei of the Department of Earth and Planetary Sciences, University of New Mexico.

Keystone species have large impacts on community and ecosystem properties, and create important ecological interactions with other species.  Prairie dogs (Cynomys spp.) and banner-tailed kangaroo rats (Dipodomys spectabilis) are considered keystone species of grassland ecosystems, and create a mosaic of unique habitats on the landscape.

Our objective was to evaluate the effects of kangaroo rat mounds on species diversity and composition at a semiarid-arid grassland ecotone. We expected that source populations of plants occurring on kangaroo rat mounds have important influences on species composition of vegetation at the landscape scale, and that these influences differ by grassland type.

Gunnison's Prairie Dog Use of Resource Pulses in a Chihuahuan Desert Grassland at the Sevilleta National Wildlife Refuge, New Mexico: Capture Data

Abstract: 

Seasonal environments experience cyclical or unpredictable pulses in plant growth that provide important resources for animal populations, and may affect the diversity and persistence of animal communities that utilize these resources. The timing of breeding cycles and other biological activities must be compatible with the availability of critical resources for animal species to exploit these resource pulses; failure to match animal needs with available energy can cause population declines. Adult Gunnison’s prairie dogs emerge from hibernation and breed in early spring, when plant growth is linked to cool-season precipitation and is primarily represented by the more nutritious and digestible plants that utilize the C3 photosynthetic pathway. In contrast, summer rainfall stimulates growth of less nutritious plants using the C4 photosynthetic pathway. Prairie dogs should therefore produce young during times of increased productivity from C3 plants, while pre-hibernation accumulation of body fat should rely more heavily upon C4 plants. If seasonal availability of high-quality food sources is important to Gunnison’s prairie dog population growth, projected changes in climate that alter the intensity or timing of these resource pulses could result in loss or decline of prairie dog populations. This project will test the hypothesis that population characteristics of Gunnison's prairie dog, an imperiled grassland herbivore, are associated with climate-based influences on pulses of plant growth.

Data set ID: 

241

Core Areas: 

Additional Project roles: 

37
38
39

Keywords: 

Methods: 

Gunnison’s prairie dogs will be monitored at 6 colonies, with 3 colonies each occurring with the range of prairie and montane populations. Colonies for study within the prairie populations occur at Sevilleta National Wildlife Refuge (n = 3 prairie populations) and at Vermejo Park Ranch (n = 3 montane populations). Live-trapping of prairie dogs will be conducted during 3 periods of the active seasons—following emergence (April), after juveniles have risen to the surface (mid-to-late June), and pre-immergence (beginning in August). Trapping will occur for 3-day periods, following pre-baiting with open traps. At capture, sex and body mass of each individual will be recorded. Blood and subcutaneous body fat samples will be collected nondestructively for analysis of isotopic composition. Prairie dogs will be marked with dye, and released on site immediately following processing. After trapping periods at each site have concluded, population counts will be conducted during 2-3 re-sighting (or recapture) periods for each prairie dog colony. Resighting observation periods will be ~3 hours in length, and consist of 2-6 systematic scans of the entire colony, beginning and ending from marked points outside of the colony boundary. During each observation period, prairie dogs will be counted, recorded as marked or unmarked, and location on the colony noted. Vegetation cover and composition measurements will be collected (or obtained at Sevilleta, where such data is already being collected) during pre- and post-monsoon periods of the active season. Total cover will be measured by plant species (or to genus if species is indeterminable). Total cover will be measured at 12 grid points per colony using Daubenmire frames (0.5 m x 0.5 m), and at 12 grid locations 200-800 m outside of each colony boundary. Adjacent to each Daubenmire frame, a 20 cm x 30 cm sample of vegetation will be clipped and dried for determination of volumetric moisture content of vegetation. Primary productivity variables (cover, moisture content) will be tested for correlations to individual and population-level condition indicators in prairie dogs. Carbon isotope ratios (δ13C) from prairie dog blood and fat samples will be analyzed on a continuous flow isotope ratio mass spectrometer. The relative contribution of C3 and C4 plants to the diet of each individual will be determined based upon δ13C ratios for C3 and C4 plants in the study area and a 2-endpiont mixing model, and will be calculated for each individual animal, population and season. Population estimates will be calculated using mark-resight estimates, and compared to maximum above-ground counts. The influence of resource pulses on prairie dog population parameters will be tested by comparing the vegetation cover, moisture content, and ratio of total C3:C4 plant cover to the ratio of C3:C4 plants in prairie dog diets, population estimates, and juvenile:adult ratios as an index to population recruitment.

Instrumentation: 

Instrument Name: Continuous flow isotope ratio mass spectrometer Manufacturer: Thermo-Finnigan IRMS Delta Plus Model Number: Instrument Name: Elemental Analyzer Manufacturer: Costech Model Number: ECS4010

Additional information: 

Field Crew: Hayes, Chuck; Talbot, William; Duran, Ricardo; Gilbert, Eliza; Donovan, Michael; Nichols, Erv; Sevilleta LTER prairie dog field crew led by Koontz, Terri; Sevilleta NWR prairie dog field crew led by Erz, Jon.

Small Mammal Exclosure Study (SMES) Rabbit Feces Data from Chihuahuan Desert Grassland and Shrubland at the Sevilleta National Wildlife Refuge, New Mexico (1995-2005)

Abstract: 

The purpose of this study is to determine whether or not the activities of small mammals regulate plant community structure, plant species diversity, and spatial vegetation patterns in Chihuahuan Desert shrublands and grasslands. What role if any do indigenous small mammal consumers have in maintaining desertified landscapes in the Chihuahuan Desert? Additionally, how do the effects of small mammals interact with changing climate to affect vegetation patterns over time?

This is data for numbers rabbit fecal pellets counted on each of the Small Mammal Exclosure Study (SMES) plots. Rabbit fecal pellets were counted from each of the 36 one-meter2 quadrats twice each year when vegetation was measured.

Data set ID: 

91

Core Areas: 

Keywords: 

Purpose: 

The purpose of this study is to determine whether or not the activities of small mammals regulate plant community structure, plant species diversity, and spatial vegetation patterns in Chihuahuan Desert shrublands and grasslands. What role if any do indigenous small mammal consumers have in maintaining desertified landscapes in the Chihuahuan Desert? Additionally, how do the effects of small mammals interact with changing climate to affect vegetation patterns over time? This study will provide long-term experimental tests of the roles of consumers on ecosystem pattern and process across a latitudinal climate gradient. The following questions or hypotheses will be addressed.

1) Do small mammals influence patterns of plant species composition and diversity, vegetation structure, and spatial patterns of vegetation canopy cover and biomass in Chihuahuan Desert shrublands and grasslands? Are small mammals keystone species that determine plant species composition and physiognomy of Chihuahuan Desert communities? Do small mammals have a significant role in maintaining the existence of shrub islands and spatial heterogeneity of creosotebush shrub communities?  

2) Do small mammals affect the taxonomic composition and spatial pattern of vegetation similarly or differently in grassland communities as compared to shrub communities? How do patterns compare between grassland and shrubland sites, and how do these relatively small scale patterns relate to overall landscape vegetation patterns?

3) Do small mammals interact with short-term (annual) and  long-term (decades) climate change to affect temporal changes in vegetation spatial patterns and species composition?

4) Do small mammals interact with other herbivore and granivore consumers enough to affect the species composition and abundance’s of other consumers such as ants and grasshoppers?

Data sources: 

sev091_smesrabbit_20160308.csv

Methods: 

Experimental Design: 

There are 2 study sites, the Five Points grassland site, and the Rio Salado creosotebush site. Each study site is 1 km by 0.5 km in area. Three rodent trapping webs and four replicate experimental blocks of plots are randomly located at each study site to measure vegetation responses to the exclusion of small mammals. Each block of plots is 96 meters on each side. Each block of plots consists of 4 experimental study plots, each occupying 1/4 of each block. The blocks of study plots are all oriented on a site in a X/Y coordinate system, with the top to the north. Treatments within each block include one unfenced control plot (Treatment: C), one plot fenced with hardware cloth and poultry wire to exclude rodents and rabbits (Treatment: R), and one plot fenced only with poultry wire to exclude rabbits (Treatment: L). The three treatments were randomly assigned to each of the four possible plots in each block independently, and their arrangements differ from block to block. Each of the three plots in a replicate block are separated by 20 meters. 

Each experimental measurement plot measures 36 meters by 36 meters. A grid of 36 sampling points are positioned at 5.8-meter intervals on a systematically located 6 by 6 point grid within each plot. A permanent one-meter by one-meter vegetation measurement quadrat is located at each of the 36 points. The 36 quadrats are numbered 1-36, starting with number 1 in the top left corner (north-west) of each plot (top being north), and running left (west) to right (east), then down (south) one row, and then right (east) to left (west), and so on Quadrat/rebar number one is in the northwest corner of each plot, and numbers 1-6 are across the north side of the plot west to east, then quadrat/rebar number 7 is just south of quadrat/rebar number 6, and rebar numbers increase 7-12 east to west, and so on. 3-inch nails were originally placed in the top left (north-west) corner of each quadrat. These may be difficult to see. A 3-meter wide buffer area is situated between the grid of 36 points and the perimeter of each plot.

While measuring vegetation on each quad, the total number of rabbit feces (pellets) that  were see on each quadrat was counted and recorded.

Maintenance: 

07/07/03  - Checked data for missing data points, doubles, and errors. Missing data points were recorded using periods (.), duplicates of data points were removed, and errors were corrected.  If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Removed Species, Comments, and Per fields.  Tape field was changed to ID# and observations made in the Per field were moved to the new ID# field.  No observations were made in the tape field.  EC field was added and NA was recorded in this field for this year.  Date MM/DD/YY field was changed to just DATE.  Other changes in the fields include PLT to PLOT, BLK to BLOCK, and CNT to COUNT. 

- Missing all Plots for Block 1 at the Grassland site for the spring except BLOCK 1 PLOT 1 TRT L.  Other Plots that are missing are Site G Block 2 Plot 3 Treatment C, Site G Block 3 Plot 3 Treatment R, and Site G Block 4 Plot 2 Treatment C. These plots are from the spring field season.  All plots are present for the fall, but with several data points missing.

-Missing plots are Site G Block 1 Plot 2 Treatment R and Site G Block 2 Plot 1 Treatment L.  These plots are from the fall field season.  All plots are present for spring field season. 

- Any empty cells were filled in with either a period for missing data or an NA for not applicable.

- Quads 32-36 were originally classified as Trt C in the fall at the Creosote site for Blk 3 Plt 2.  Changed the Trt to Trt R.

- Quads 10-16 were originally classified as TRT C in the fall at the Grass Site for BLOCK 4 PLOT 1.  Changed the TRT to TRT R.

- For the fall field season at the Grass Site, BLOCK 2 PLOT 4 TRT R QUAD 7 was classified as Creosote, changed to Grass Site. 

- Quads 21-24 were originally classified as Trt C in the spring at the Grass site for Blk 4 Plt 3.  Changed the Trt to Trt L.

- Quads 10-17 were originally classified as TRT C in the spring at the Creosote Site for BLOCK 2 PLOT 2, changed the TRT to TRT L.

- Spring Field Season Changes

For BLOCK 1 PLOT 2 TRT R and BLOCK 2 PLOT 1 TRT L all quads classified as Creosote Site, changed to Grass Site.

For quads 1-18 at the Creosote Site for BLOCK 2 PLOT 1 TRT C, originally classified as PLOT 4, changed to PLOT 1.

For Creosote Site BLOCK 4 PLOT 2 TRT C: Quads 1-4, 28-35 originally PLOT 1 changed to PLOT 2 Quads 5-19 originally PLOT 3 changed to PLOT 2

- Fall Field Season Changes

For quads 1-18 at the Creosote Site for BLOCK 1 PLOT 4 TRT R, originally classified as PLOT 3, changed to PLOT 4.

- Spring Field Season Changes

For Grass Site BLOCK 1 PLOT 4 TRT C Quads 1-30, originally classified as BLOCK 2, changed to BLOCK 1.

For Grass Site BLOCK 3 PLOT 4 TRT C Quads 20-36, originally classified as BLOCK 4 PLOT 3, changed to BLOCK 3 PLOT 4.  

- Fall Field Season Changes

For Creosote Site BLOCK 2 PLOT 2 TRT L, date changed from 10/09/00 to 11/09/00 for quads 26-36.

For Grass Site BLOCK 1 PLOT 4 TRT C, date changed from 10/06/00 to 11/06/00 for quads 23-29.    

 - Any empty cells were filled in with either a period for missing data or an NA for not applicable.

 - Terri Koontz

07/14/03  - Modified metadata to correct format.

- Terri Koontz

07/21/03  - Spring Field Season Changes

For Grass Site BLOCK 2 PLOT 1 TRT L, there were two observations for some quads that had different dates (05/02/95, 05/03/95, and 05/04/95).  All data points with either 05/02/95 or 05/03/95 were changed to BLOCK 1 PLOT 1 TRT L.  This was done because one other plot for BLOCK 2 had some quads with this same date.  Also, it seemed logical that BLOCK 1 would have been measured first.

- Terri Koontz

07/29/03  – For fall at the Grass Site BLOCK 1 PLOT 4 TRT C QUADS 10-18 had double observations.  For one set of observations, the BLOCK was changed to BLOCK 3.  This was determined by looking at another year for vegetation data to see which set had similar values and species composition for BLOCK 3.

 - Terri Koontz

07/30/03  - Quads 11-14 were originally classified as TRT C in the spring at the Creosote Site for BLOCK 3 PLOT 4, changed TRT to TRT L.

- Terri Koontz

07/22/03  - Checked data for missing data points, doubles, and errors. Missing data points were recorded using periods (.), duplicates of data points were removed, and errors were corrected.  If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Date MM/DD/YY field was changed to just DATE.

- Fall Field Season Changes

Changed dates to reflect that data was measured in 2001 and not in the 1970s.

Changed in the ID# field ‘1’ to SMESVQF01CR1, ‘2’ to SMESVQF01CR2, and ‘3’ to SMESVQF01CR3.

For Creosote BLOCK 2 PLOT 3 TRT R QUADS 34 and 36, originally BLOCK 1 PLOT 3 TRT R, changed BLOCK 1 to BLOCK 2. 

For Grass BLOCK 3 PLOT 4 TRT C, originally recorded as Creosote Site, changed to Grass Site.

For Grass BLOCK 4 PLOT 2 TRT C, originally recorded as Creosote Site, changed to Grass Site.

- Any empty cells were filled in with either a period for missing data or an NA for not applicable.

- Terri Koontz

03/14/06  - Checked data for missing data points, doubles, and errors. Missing data points were recorded using -999 (human Error), duplicates of data points were removed, and errors were corrected. If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Date MM/DD/YY field was changed to just DATE. BLOCK field was changed to BLK.

- Changed dates to reflect that data was measured in 2002 and not in the 1970s.

- Changed to "1" in the EC field with comments.

- Any empty cells were filled in with -999 (human Error) for missing data or an NA for not applicable.

- Yang Xia

03/15/06  - For the Spring field season at the Creosote site, Plots missing are BLK 1 Plot 1 Trt C and BLK 3 Plot 3 Trt C. These plots are added to the dataset as missing values.

- Metadata was modified to correct format.

- Yang Xia

03/23/06  - changed start date from september 1995 to May 1995 in the research Hypotheses, since the data collection was starting on 05/02/95. 

- Yang Xia

05/02/06  - Checked data for missing data points, doubles, and errors. Missing data points were recorded using -999 (human Error), duplicates of data points were removed, and errors were corrected. If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Date MM/DD/YY field was changed to just DATE. BLOCK field was changed to BLK.

- Changed dates to reflect that data was measured in 2003 and not in the 1970s. for the data of measured in August, changed to October. 

- Changed to "1" in the EC field with comments.

- Any empty cells were filled in with -999 (human Error) for missing data or an NA for not applicable.

- Yang Xia

06/12/06  - Checked data for missing data points, doubles, and errors.  Missing data points were recorded using -999 (human Error), duplicates of data points were removed, and errors were corrected. If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Date MM/DD/YY field was changed to just DATE. BLOCK field was changed to BLK.

- Changed dates to reflect that data was measured in 2004 and not in the 1970s and 1990s. 

- Changed to "1" in the EC field with comments.

- Any empty cells were filled in with -999 (human Error) for missing data or an NA for not applicable.

- Yang Xia

06/14/06  - Modified metadata to correct format.

- For Creosote Site in the Spring, changed BLOCK 4 PLOT 1 TRT C QUAD 17-21 to BLOCK 4 PLOT 1 TRL L QUAD 17-21.

- For Grassland in the Spring, changed BLOCK 4 PLOT 1 TRT C QUAD 31-36 TO BLOCK 4 PLOT 1 TRT R QUAD 31-36.

- Yang Xia

06/26/06  - Checked data for missing data points, doubles, and errors. Missing data points were recorded using -999 (human Error), duplicates of data points were removed, and errors were corrected. If a data point contained a measurement of zero and a measurement with a count, the zero observation was removed.

- Date MM/DD/YY field was changed to just DATE. BLOCK field was changed to BLK. Tapeid was changed ID #.

- Any empty cells were filled in with -999 (human Error) for missing data or an NA for not applicable.

- Yang Xia

07/03/06  - Modified metadata to correct format. 

- An NA for not applicable in the EC field for 2005.

- Yang Xia

Additional information: 

Additional Information on the personnel associated with the Data Collection / Data Processing

Sevilleta Field Crew Employee History

Megan McClung, April 2013-present, Stephanie Baker, October 2010-Present, John Mulhouse, August 2009-Present, Amaris Swann, August 25, 2008-January 2013, Maya Kapoor, August 9, 2003-January 21, 2005 and April 2010-March 2011, Terri Koontz, February 2000-August 2003 and August 2006-August 2010, Yang Xia, January 31, 2005-April 2009, Karen Wetherill, February 7, 2000-August 2009, Michell Thomey, September 3, 2005-August 2008, Jay McLeod, January 2006-August 2006, Charity Hall, January 31, 2005-January 3, 2006, Tessa Edelen, August 15, 2004-August 15, 2005, Seth Munson, September 9, 2002-June 2004, Caleb Hickman, September 9, 2002-November 15, 2004, Heather Simpson, August 2000-August 2002, Chris Roberts, September 2001-August 2002, Mike Friggens, 1999-September 2001, Shana Penington, February 2000-August 2000.

Gunnison's Prairie Dog Relocation Project: Vegetation Cover Data from the Sevilleta National Wildife Refuge, New Mexico (2005-2013)

Abstract: 

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.

Core Areas: 

Data set ID: 

212

Keywords: 

Methods: 

Experimental Design

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 sources: 

sev212_pdogvegcover_20130509.txt

Maintenance: 

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

Additional information: 

More information about who is involved with the samples/data:

Mike Friggens 1999-September 2001
Karen Wetherill February 7, 2000-Augst 2009
Terri Koontz February 2000-August 2003
August 2006-Present
Shana Pennington February 2000-August 2000
Heather Simpson August 2000-August 2002
Chris Roberts September 2001-August 2002
Caleb Hickman September 9, 2002-November 15, 2004
Seth Munson September 9, 2002-June 2004
Maya Kapoor August 9, 2003-January 21, 2005
March 2010-March 2011
Tessa Edelen August 15, 2004-August 15, 2005
Charity Hall January 31, 2005-January 3, 2006
Yang Xia January 31, 2005-Present
Michell Thomey September 3, 2005-August 2008
Jay McLeod January 2006-August 2006
Amaris Swann August 25, 2008-Jan 2013
John Mulhouse August 2009-Present
Amanda Boutz August 2009-May 2010
Stephanie Baker October 2010-Present
Megan 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 m

Soils: sandy loam and sandy clay loam

Site history: historically large prairie dog colonies inhabited the study area

Burn Exclosure Rodent Population Study at the Sevilleta National Wildlife Refuge, New Mexico (1991-1993)

Abstract: 

Small mammal densities were estimated from small mammal recapture data in burned and unburned grassland.

Data set ID: 

15

Additional Project roles: 

53

Core Areas: 

Keywords: 

Methods: 

Web trapping design:

Experimental units were established in a 4 x 4 grid as part of a burn and antelope exclosure experiment. Small mammals were trapped in fireblocks 1, 2, 3, and 4. Each fireblock contains four webs, for a total of 16 webs. Small mammal densities are estimated from recapture data.

Within each location four webs were established. Each web contains twelve 100m transects radiating from a central point in a spoke like fashion. Four "Sherman" traps were placed around this central point. Twelve traps are placed along each of the radiating lines, the first four are placed at 5m intervals, and the remaining eight placed at 10m intervals. Rebar were used to mark the location of trap placement. Each rebar was tagged with a number from 1 to 145, with trap number 1 at the north facing spoke and radiating out to trap number 12, with each spoke following with successive numbers increasing in a clockwise fashion. Trap number 145 includes the four traps placed in the center of the web. Traps were placed adjacent to rebar unless a shaded area could be found within a meter or so along an arc of equal radius from the center. The webs are separated by distances from approx. 100m to 600m. Within each fireblock, each web is marked with a number from 1-4.

Trapping times:

Each summer was divided into two periods: period 1 and period 2.
Mammals were trapped as follows:

1991: period 1: NA
         period 2: September 4 - October 4
1992: period 1: April 15 - May 8
         period 2: August 4 - September 17
1993: period 1: April 6 - 29
         period 2: September ??

Each location was trapped in the same order for each period.
The order is as follows:

1. Fireblock 1
2. Fireblock 2
3. Fireblock 3
4. Fireblock 4

Each trapping session consisted of placing and baiting traps on Monday, then checking the traps at dawn on both Tuesday (night 1), Wednesday (night 2), and Thursday (night 3). The traps were collected on Thursday after being checked for animals. A small handful of rolled oats was placed into each trap, with small amounts placed outside trap door. Animals were removed form closed traps with the aid of plastic bags. They were then identified to species. Weight was determined to the nearest gram using a pesola scale. Body, tail, foot, and ear measurements were taken for Peromyscus. Body and tail measurements were taken for Onychomys, Perognathus, and Reithrodomtomys. All measurments were taken to the nearest millimeter using a plastic ruler. Reproductive status was determined by examination of the genitalia. The animal was also sexed, aged, and marked. Marking was done to each animal on the first nights capture for each individual animal.

Data sources: 

sev015_burnxrodentpop_10191995.txt

Maintenance: 

File created by Susan McKelvey 3/29/93. File supplemented by Rosemary Vigil 24 June 1993. Checked Oct 20, 1995; James Brunt

Quality Assurance: 

Data Entry

1. Data were entered at Biology Annex using data entry program "mammal-entry"
2. Data were checked for errors by comparing original data sheets with the
data entered into the computer.
3. After all errors were corrected, a dbf file was created using a Sun machine.
(/research/local/mammal/bin/SASmam2dbf filename > filename.dbf) This
modifies the comments, leaving out comments noted as "na".
4. A rdb file was then created using "arc2rdb filename.dbf > filename.rdb".
5. The rdb file was then checked for errors using "check < filename.rdb".
6. After errors were corrected, the rdb file was sorted using "sort
filename | uniq -c | page" to check that every entry was unique.
7. Duplications were investigated and corrected.
8. Dbf and rdb files were then copied to /research/archive/dbwork/vertebrate/
mammal/burnplot
9. From sevilleta, at burnplot>, the rdb file was run through a program called
webDist to create an input file as such: " webDist filename.rdb location
period > conventional input name. (naming conventions: site-season-year.in)
10.Input file was copied into /research/archive/dbwork/vertebrate/mammal/
burnplot
11.From a PC, the input file was run through a distance program in order to
get densities. (from dos: L:, cd distance, dist i=L:\burnplot/filename.in
o=L:\burnplot\filename.out)
12.Densities were cbtained from the output file and put into /mammal/data/
density-data/mammal_densities.data.burn which is a table containing the
following: year season location web n density stderr cv lcl ucl.
13.At this point, nothing further has been done.

Effects of Kangaroo Rats on Plant Species Dominance in a Chihuahuan Desert Grassland at the Sevilleta National Wildlife Refuge, New Mexico (1988)

Abstract: 

Our objective was to evaluate the effects of burrowing activities by banner-tail kangaroo rats (Dipodomys spectabilis Merriam) on plant community structure and species dominance for two patch types at an ecotone between shortgrass steppe and desert grasslands in New Mexico, USA. Ten mounds produced by kangaroo rats were selected in patches dominated by Bouteloua gracilis (the dominant in shortgrass steppe communities) and ten mounds were selected in patches dominated by Bouteloua eriopoda (the dominant in Chihuahuan desert grasslands). Plant cover and density by species were sampled from three locations associated with each mound: the mound proper, the edge of the mound in the transition area, and the off-mound vegetation. Similar cover of B. eriopoda for the edges of mounds in both patch types indicates the ability of this species to respond to animal disturbances regardless of the amount of cover in the surrounding undisturbed vegetation. By contrast, cover of B. gracilis was low for all mounds and mound edges in patches dominated by this species. Much higher cover of B. eriopoda on mound edges compared to the undisturbed vegetation in B. gracilis- dominated patches indicates that kangaroo rats have important positive effects on this species. Lower cover of perennial grasses and higher cover of forbs, shrubs, and succulents on the edges of mounds in B. eriopoda - dominated patches compared to patches dominated by B. gracilis indicate the importance of surrounding vegetation to plant responses on disturbed areas. Our results show that kangaroo rats have important effects on both species dominance and composition for different patch types, and may provide a mechanism for small-scale dominance patterns at an ecotonal boundary; thus providing further support for their role as keystone species in desert grasslands.

Core Areas: 

Data set ID: 

144

Additional Project roles: 

190

Keywords: 

Data sources: 

sev144_kratdominance_08052003.txt

Methods: 

Study Description

Kangaroo rats have dramatic affects on vegetation structure in a number of patch types or landscape units including those dominated by various species of grasses and shrubs. As a result of these large effects on the vegetation relative to their low abundance, bannertail kangaroo rats have been identified as keystone species. At the ecotone between Chihuahuan desert grasslands and shortgrass steppe communities in central New Mexico, kangaroo rats affect patches dominated by Bouteloua eriopoda (Torr.) Torr. (black grama), the dominant grass in Chihuahuan desert grasslands, or Bouteloua gracilis (H. B. K.) Lag ex Steud. (blue grama), the dominant grass in shortgrass steppe communities. These two species differ in their life history traits, especially in response to disturbances that may affect their ability to dominate in the presence of small disturbances, such as mounds produced by banner-tail kangaroo rats. B. eriopoda is a short-lived grass that may respond rapidly to disturbance through the production of long stolons. By contrast, B. gracilis is a long-lived, slow-growing bunchgrass with limited ability to respond to disturbance either vegetatively or through seedling establishment. Differences in species or lifeform composition of patches dominated by one or the other Bouteloua species may result in patch-specific patterns in vegetation associated with mounds.
Study Begin Date: 1-Jun-1998
Study End Date: 1-Aug-1998

Research Methods

Study Methods: Mound selection: Banner-tail kangaroo rat mounds were selected from within patches dominated by either B. eriopoda or B. gracilis where dominance was based on average cover > 750f total plant cover. We identified a total of eight patches, four dominated by each Bouteloua species, from within a 400m x 1000 m area; each patch was ca 200 m x 200m in size. From within each patch, we identified five active kangaroo rat mounds where activity was determined by unobstructed entrances to burrows and/or fresh fecal material near a mound. Only active mounds were used in this study in order to minimize variation in vegetation and soil properties due to recovery processes that begin after a mound is abandoned. Although mound age could not be determined, mounds are sufficiently long-lived (> 30y) that differences in age are unlikely to affect vegetation dynamics. We then randomly selected a total of ten mounds to be sampled in each patch type. The area of each mound was estimated by measuring its outer length in two cardinal directions (north-south, east-west), and assuming an elliptical shape. Because average mound size was similar in B. eriopoda (11.3 m2) and B. gracilis (12.0 m2), mound size was not needed as a covariate in our analyses.

Vegetation sampling: Average mound radius was used to locate the center of each mound. Vegetation was sampled in July along four transects radiating within 5o of the four cardinal directions from the center of each mound, and extending to a distance of 25 meters away in vegetation considered typical of the patch type between mounds. Variation in the direction was necessary to avoid nearby mounds. Data were collected using a 2.0-m2 quadrat placed at nine locations along each transect (in m from the mound center): 0.0, 1.5, 3.0, 5.0, 7.5, 10.0, 15.0, 20.0, and 25.0. Distance between quadrats was short near the mound to allow intense sampling of this area and to increase sample size; most of the length of each transect was contained in the typical patch vegetation, thus longer distances between quadrats were used. Each quadrat was recorded as occurring at one of three locations: on the mound ("mound"), at the edge of the mound in the transition area ("edge"), or off the mound in typical vegetation between mounds ("off-mound"). Locations were defined based upon the frequency and intensity of burrowing activities of kangaroo rats as well as the amount of bare ground. Mound locations were characterized by frequent, unobstructed entrances to burrows, predominantly bare ground, and elevated topography. Edges were defined as the transitional area surrounding mounds that contained few burrows with an intermediate amount of bare ground. Off-mound vegetation was characterized by no burrowing activity and low amounts of bare ground.

For each quadrat, canopy cover only (to the nearest 1%) was estimated for bare ground and litter combined, and by species for perennial grasses where vegetative spread by tillers or stolons makes identification of individuals difficult, thus density estimates are imprecise. Data were collected by species for B. eriopoda, B. gracilis, and other frequently occurring grasses including Hilaria jamesii, Sporobolus flexuosus, and Aristida purpurea; all other perennial grasses were combined into one cover estimate for each quadrat. Canopy cover (%) and density (no./2 m2) were estimated for species where individual plants are easily determined, including shrubs (Gutierrezia sarothrae, Ephedra viridis) and succulents (Yucca glauca, Opuntia spp.). Cover and density of annual and perennial forbs and sub-shrubs including Psilostrophe tagetina, Glandularia wrightii, Hymenopappus filifolius, Sphaeralcea spp., Machaeranthera pinnitifida, Solanum elaeagnifolium, Plantago patagonica, Salsola kali, Astragalus spp., Chaetopappa ericoides, Cryptantha crassisepala, and Kraschninnikovia lanata were determined as a group for each quadrat due to low frequencies of occurrence. Because sampling was conducted in the middle of the growing season (July), cover of all species are likely under estimates of peak growth for that year.

Statistical analyses: The data were analyzed using analysis of variance to test for the significance of patch type (B. eriopoda- or B. gracilis - dominated) and sampling location (mound, edge, off-mound) on cover or density of the vegetation. The design included patch type as the between subjects factor and location as the within subject factor. Dependent variables were analyzed separately, and included cover of five species or species-groups: (1) B. eriopoda; (2) B. gracilis; (3) other grasses combined; (4) forbs, shrubs and succulents combined; and (5) the total. Species-groups were used for grasses other than the two Bouteloua species, and for forbs, shrubs and succulents due to small sample sizes for individual species. Density of the forbs, shrubs, and succulents group was also analyzed. Least significant difference (LSD) means comparison tests were used to identify significantly different means at the 0.05 level. Two separate means comparisons tests were conducted for each response variable. Effects of patch type were determined by comparing cover or density of each species or group within the three locations. A similar analysis was conducted for determining effects of location on cover or density within each patch type.

Maintenance: 

July 25, 2003 -- File created by Kristin Vanderbilt from Excel metadata and data files submitted by Deb Peters. -- KLV

Additional information: 

Additional Information on the personnel associated with the Data Collection / Data Processing

Other field crew members: Jon Erz & Teresa Seamster

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