Please note: this presentation has not received Director

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Please note this presentation has not received
Directors approval and is subject to revision.
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USGS American Alligator and Amphibian Research in
the Everglades

• Kenneth G. Rice

USGS Center for Water and Restoration Studies
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Collaboration

• Co-Pis
• Logistical support
• Students
• Temporary hires

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Do Alligators Need Restoration?
Longer Age to Maturity
Lower Growth Rates
Smaller Clutch Size
Decreased Population Size
Increased Nest Flooding
Skewed Size Distribution
Higher Mercury Levels
Decreased Nest Production
Large Canal Populations
Fewer Alligator Holes
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Population Models
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Vital Rates/Parameters

• Spatial, temporal, and hydrological gradients.
• Model Parameters.
• Movement/spatial dynamics
• Habitat use
• Thermoregulation
• Condition
• Growth
• Survival

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Telemetry
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Adult home range and movement
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Alligator Habitat Use
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Monitoring

• Across space and time.
• 8 populations in South Florida.
• Parameters
• Population Trends
• Size Distributions
• Condition
• Growth
• Mercury and other contaminants
• Blood characteristics and health
• Food habits

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Body Condition
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Growth

• Collaborators
• Allan Woodward

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Skeletochronology
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Field Activities FY04

• Alligator monitoring program.
• Density, Size distribution, Condition.
• Correction factors.
• Alligator holes.
• Mapping.
• Ecological characterization.
• Juvenile movement.
• GPS telemetry
• Habitat use in Big Cypress

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Models

• Production Index
• M. Palmer, UT
• Stage/Age-based Population Model
• D. Slone, USDA

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ATLSS Alligator Population Model

• Stage/Age Structured Matrix Model
• Runs on PC in Matlab

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User Interface
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Daily water levels (SFWMD and ATLSS)
Yearly nesting submodel (ATLSS API)
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Alligator densities, Calibration data
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Alligator population densities metadata on
condition
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Basic model cycle
Starting alligator densities
Survival and Development
Alligator habitat area
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Virtual Night-Light Survey Airboat Trails
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Model CalibrationVirtual Night-Light Surveys
Shark Slough
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Model Calibration(Water Conservation Area 2A)
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Alt D13R compared with 1995 Base
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Alt D13R compared with F2050
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Alt D13R compared with 1995 Base in a dry year
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Egg production of Alt D13R compared with 1995
Base in a wet year
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APM FY04

• Continue validation.
• Project modeling.
• New areas/hydrologic models.
• Canal models.

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3 speciesPig frog, Southern Toad, Leopard Frog
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Testing Restoration Hypotheses
B
A
B
A
B
Restoration Target
Current Conditions
In 5 years
E
Monitoring
E
D
C
D
C
D
C
Hypothesis
Restoration Success
Restoration Gain
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Thanks!!