alexis a. suazo research assistant public lands institute university of nevada las vegas

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