alexis a. suazo research assistant public lands institute university of nevada las vegas
TRANSCRIPT
Alexis A. SuazoAlexis A. Suazo
Research AssistantResearch Assistant
Public Lands InstitutePublic Lands Institute
University of Nevada Las VegasUniversity of Nevada Las Vegas
Current Projects
• Control Methods for Sahara mustard (Brassica tournefortii )
• Spatial distribution during early invasion• Role of native granivorous rodents • Ants and beetles as potential bio-
indicators of restored habitats
Sahara mustard
Control methods
Sah
ara
mu
star
d (
seed
ling
s m
2 )
0
20
40
60
80
100 Water
Disturbance Water + disturbance
Control
Spatial distribution
Rodent / Seed interactions
Seed predation
Burial depth (cm)
2 5 10
Rec
ove
red
see
d p
acke
ts (
%)
0
20
40
60
80
Open Shrub
Insects
Responses of small mammals to restoration and management techniques of Florida scrub at Cape
Canaveral Air Force Station, Florida
Florida- Coastal Scrub
After Burning
Remnant scrub
• Coastal development and fire suppression
• Reduced to small fragmented, isolated patches
Degraded habitat
Urban interface
Management
Combination of mechanical treatment followed by
prescribed burning
Species Responses
Breininger et al. 1995Conservation Biology 9:1442-1453
• Treatments are effective
• Florida scrub-jays
What about other species
• PlantsLots of studies from Archbold Biological Stations
• Amphibians and ReptilesGopher tortoise (Gopherus polyphemus) populations are
declining in some protected areas
McCoy et al. 2006
Biological Conservation 128:120-127
• Small mammals Very little is known
Small mammal research
• Objective 1 Document the effects of mechanical fuel reduction, prescribed-
burning, and mechanical fuel reduction/prescribed-burning combination treatments on small mammal relative abundance
• Objective 2 Examine whether individual body mass and reproductive condition varied
among treatments
• Objective 3 Examine relationships between Florida scrub-jay and small mammal
populations
Broader Application of Research
• Based line data for long-term monitoring
• Adaptive Management
• Aid in planning and management of habitat for multiple species
• Incorporate management techniques in recovery of listed species
Small mammals• Southeastern beach mice
(Peromyscus polionotus niveiventris)• Endemic • Federally listed• Habitat specialist
Cotton mice• Peromyscus gossypinus• Common • Habitat generalist
Cotton rats
• Sigmodon hispidus
• Common
• Habitat specialist
Study Area
Cape Canaveral Air Force Station (CCAFS) near Titusville, FL
Coastal Scrub
• Dominant community type• Degraded • 50 yrs of fire suppression• Restoration began in 1995
Burned (N = 5) Cut (N = 6)
Cut & Burned & Checkerboarded (N = 4) Fire suppressed (N = 3)
Methods
Fire suppressed
Cut
Burned
Cut & Burned & Checkerboarded
Small Mammal Trapping
Individual identification
Data Analysis
• Used repeated measures analysis of variance (RM- ANOVA) to test for treatment effects• Seasons were the repeated variable• Response variablesfirst-time captures
body mass
•Used a G-testreproductive condition
Data Analysis Cont.
• Used correlation to examine relationships between FL scrub-jays and southeastern beach mice
• Used Bonferroni Multiple Comparison test to differentiate between means
• Data met parametric assumptions• Test P< 0.05, were statistically significant
Seasonal abundance
Peromyscus polionotus Peromyscus polionotus niveiventrisniveiventris (black)P. gossypinusP. gossypinus (gray)Sigmodon hispidusSigmodon hispidus (open)
Treatment abundance
P. p. niveiventrisP. p. niveiventris (black)
P. gossypinusP. gossypinus (gray)
Sigmodon hispidusSigmodon hispidus (open)
Treatment responseP. p. niveiventrisP. p. niveiventris P. gossypinusP. gossypinus
Fall Winter Spring Summer
Fall Winter Spring Summer
Fall Winter Spring Summer
Season * treatment, F 9, 42 = 2.66, P = 0.015
Treatment, F 3, 14 = 4.79, P = 0.017
Season * Treatment, F9, 39 = 1.58, P = 0.15
Treatment, F 3, 14 = 1.54, P = 0.246
Body mass Fall Winter Spring Summer
P. p. niveiventrisP. p. niveiventris
P. gossypinusP. gossypinus
S. hispidusS. hispidus
33
11
33
55
448888
66
77
44
11
77
66
33
22
991212
242417171111
88
77
33
1111
8810101212
44
22997777993232
20202222
ReproductionP. p. niveiventrisP. p. niveiventris (males)
P. gossypinusP. gossypinus (males)
P. p. niveiventrisP. p. niveiventris (females)
P. gossypinusP. gossypinus (females)
Non-reproductive Reproductive
Non-reproductive Reproductive
ReproductionP. p. niveiventrisP. p. niveiventris (males) P. p. niveiventrisP. p. niveiventris (females)
P. gossypinusP. gossypinus (males) P. gossypinusP. gossypinus (females)
Non-reproductive Reproductive
Non-reproductive Reproductive
G = 8.148, d. f. = 3, P < 0.05
Florida scrub-jayFlorida scrub-jay groups
using compartmentsSoutheastern beach
mouse
CompartmentArea (ha)(burned)
2004Census
Breeding Season Nesting Fledging Number of first-time captures
4 93(40) 10 8 8 0 24
7 15(15) 4 7 6 4 12
37 7(7) 2 3 1 2 20
*48 19(0) 1 3 3 11 4
*67 8(0) 0 2 0 0 3
69 24(0) 2 3 1 0 11
81 13(0) 3 4 1 0 4
87 23(12) 1 2 1 3 26
101 12(0) 1 5 2 0 5
*102 4(0) 0 4 0 N/A 7
*104 6(0) 5 3 4 4 11
115 12(12) 0 2 0 0 1
55 34(0) 0 0 0 0 2
118 9(0) 0 1 1 0 16
Florida scrub-jay data are from Stevens and Knight 2003-2004 annual report
* Cut but unburned
Relationships
r = 0.51, P < 0.05
Conclusion Objective 1 Document treatment effects
Land management activities influenced small mammal populations
Objective 2 Treatment effects on body mass and reproductive condition No significant responses were found
Objective 3 Florida scrub-jay and small mammal populations relations Positive correlation was found, suggesting that both species benefit from
management activities