Transcript Small Mammal Population and Diversity in Relation

Summer 2013
Ty Werdel
Chadron State College
Wildlife Management
 Prairie
Dogs (Cynomys) are considered
ecosystem engineers and a keystone
species
 Impact abiotic and biotic features
• Influence environmental heterogeneity, plant
succession, hydrology, nutrient cycling,
landscape architecture, and biodiversity
 Historical
Range (1800)
 Historically
occupied millions of hectares
of land
• Populations have declined by 90%-98%
• Range disappearing due to encroachment on
habitat and eradication
 Implications
of Losing an Ecosystem
Engineer
• Many vertebrate species have been shown to
depend on prairie dogs for habitat and survival.
• Result in loss of species diversity in grasslands
• Endangered or Species of Concern:
 Prairie
Dog’s Impact on Small Mammals
• Utilize prairie dog burrows for dens, shelter, and
predator avoidance
• Species richness, diversity, and abundance has
been shown to increase in areas with prairie
dogs
• Certain species are adapted to live in areas with
short grass and bare ground.
 What
is the effect of C. gunnisoni on small
mammal species diversity and
abundance on Sevilleta NWR?

Refuge Purpose for Reintroduction
• Native, Eradicated, Reintroduced
• Establish habitat for the prairie dog and for the many life
forms that depend on its system

Reintroduction History
• Reintroduction within Sevilleta National Wildlife Refuge in
2010
 4-16
ha Vegetation Plots
• Plot A- Control
• Plot B- Prairie Dog Reintroduction
• Plot C-Control
• Plot D- Prairie Dog Reintroduction
• Traps Placed in 9 ha Grid
• 169 Traps
• Arranged 25 M apart
1
Plot/Week
 4 Weeks
• Control Plots
 A- June 3-7
 C- June 10-14
• Treatment Plots
 B- June 17-21
 D- June 24-28
PROCEDURE:

Trapped/Baited 5
Consecutive Days Per
Week
• Monday-Friday
PROCESSING:

Data Was Collected
Regarding: Species, Sex,
Age, Weight, and
Measurements
• Individuals marked

Heteromyidae

• Kangaroo Rats
 Dipodomys merriami
 Dipodomys ordii
 Dipodomys Spectabilis
• Pocket Mice
 Perognathus flavus

Sciuridae
• Ground Squirrels
 Spermophilus spilosoma
Merriam’s
Kangaroo
Rat
Silky
Pocket
Mouse
Cricetidae
• Woodrats
 Neotoma micropus
• Grasshopper Mice
 Onychomys leucogaster
 Onychomys arenicola
• Mice
 Peromyscus boylii
 Peromyscus maniculatus
Brush
Mouse
9
8
8
Total Species
7
7
7
6
6
5
4
3
2
1
0
A
B
C
Plot
D
120
Total Individuals
100
80
60
96
90
70
68
40
20
0
A
B
C
Plot
D
Average Total Individuals
100
80
93
60
40
69
20
0
Control
Treatment
P-Value: 0.3168
Not Significant
70
63
61
Total Individuals
60
50
Plot
41 42
A
40
B
C
30
D
20
20
12
8
10
3
5
9
8
6 6
1 2 2
1
1
2
2
7
4
3
1
4 5
2 3
0
DIME DIOR
DISP
NEMI ONAR ONLE PEBO PEMA PGFV
Species
SPSP
70
63
61
Total Individuals
60
50
Plot
41 42
A
40
B
C
30
D
20
20
12
8
10
3
5
9
8
6 6
1 2 2
1
1
2
2
7
4
3
1
4 5
2 3
0
DIME DIOR
DISP
NEMI ONAR ONLE PEBO PEMA PGFV
Species
SPSP
70
63
61
Total Individuals
60
50
Plot
41 42
A
40
B
C
30
D
20
20
12
8
10
3
5
9
8
6 6
1 2 2
1
1
2
2
7
4
3
1
4 5
2 3
0
DIME DIOR
DISP
NEMI ONAR ONLE PEBO PEMA PGFV
Species
SPSP
70
63
61
Total Individuals
60
50
Plot
41 42
A
40
B
C
30
D
20
20
12
8
10
3
5
9
8
6 6
1 2 2
1
1
2
2
7
4
3
1
4 5
2 3
0
DIME DIOR
DISP
NEMI ONAR ONLE PEBO PEMA PGFV
Species
SPSP
 Small
Mammal Species Richness
• Doesn’t seem to be a correlation between
species richness and control or treatment sites
 Small
Mammal Abundance
• No significant difference
• Seems to be a trend favoring abundance on
treatment plots versus control plots
 Previous
Research
• Short term studies may not show significant data
• Prairie dogs may have a different effect on
different grassland types
• Black-tailed vs. Gunnison’s
 Abundance
of Small Mammals Low:
• Only 1 Trapping Period Per Site
• Season of Trapping
• Drought vs. Monsoon
• Low mammal activity

Data Not Significant:
• Low abundance over all plots
• Less variation between plots
 Baseline
Data
• 1st year being researched
• Build upon this data
 Methods
• Extend trapping periods
• Increase amount of traps
• Trap during different seasons
 Concentrate
on
Specific Species
• Perognathus flavus
• Dipodomys merriami
• Peromyscus
 GIS/Spatial
Mapping
• Vegetation
• Prairie Dog Burrows
• Trap Data
 Special Thank You
to:
• Jon Erz
• Stephanie Baker
• Amaris Swann
• U.S. Fish and Wildlife Interns
• REU Students