# Presentation: 180486

## DESERT 

**	****TORTOISE **
**	****	****	****CONCEPTUAL**
**	****	****	****	****	****	****MODEL**

**U.S. FISH & WILDLIFE SERVICE**

**                                     ****PHILIP A. MEDICA**

##     ACKNOWLEDGMENTS

- Todd Esque, U.S. Geological Survey, Las Vegas Field 	Station, Las Vegas, NV
- John Hamill, U.S. Department of Interior, Barstow, CA
- Debra Hughson, National Park Service,
- 	Mojave National Preserve, Barstow, CA
- Robert Fulton, California State University,  Desert 	Studies Center, Zzyzx, CA
- Jim Andre’, University of California, Riverside, 	Granite Mountain Desert Research Center, 	Kelso, CA

## OBJECTIVE:

**	****The objective of the Desert Tortoise Conceptual Model**
**is to guide the development of a multifaceted, ecologically **
**adaptive, predictive tool.  This model will assist in predicting **
**the population fluctuations with varying environmental inputs**
**that impact survivorship, reproduction, longevity, as well as **
**population structure and function.**
**	**
**	****This Model will assist in the evaluation of desert tortoise recovery rangewide, and will be  usable as a predictive tool for the evaluation of management practices.**

##   DESERT

**  ****DESERT**
**     ****TORTOISE **
**        ****POPULATIONS**

**ABIOTIC**
**   ****FACTORS**

**BIOTIC**
**   ****FACTORS**

## ABIOTIC

**ABIOTIC**
**  ****FACTORS**

**ABIOTIC**
**FACTORS**

**SOLAR**
**RADIATION**

**  ****RAINFALL**

**TEMPERATURE**

**     ****ENSO &  PDSO**

**GEOMORPHOLOGY**

**    ****CATASTROPHIC **
**            ****EVENTS**

**ELEVATION**

**SLOPE**

**AGE**

**ASPECT**

**SUBSTRATE**

**WIND/DUST**

## SUBSTRATE

**SUBSTRATE**

**SOIL**
**TYPE**

**CHEMICAL**
**COMPOSITION**

**CRYPTO-**
**BIOTIC**
**CRUST**

**BURROWING**
**QUALITIES**

**TEXTURE**

**STRUCTURE**

## BIOTIC FACTORS

**BIOTIC FACTORS**

**DESERT TORTOISE HABITAT COMPONENTS**

**MICROORGANISMS**

**PREDATORS**

**NATURAL  HISTORY**

**DISEASE**

**PARASITES**

**VEGETATION**

##    TORTOISE

-    **TORTOISE**
**   ****NATURAL **
**    ****HISTORY**

**LONGEVITY**

**SEX/AGE RATIO**

**MORTALITY**

**NATALITY**

**FOOD/WATER**

**ACTIVITY**

**BEHAVIOR**

**DISPERSAL**

**GENETICS**

**MORPHOLOGY**

**GROWTH**

**HOME RANGE**

**       ****HABITAT**
**    ****SELECTION**

**    ****PARASITES**

**PREDATORS**

**POPULATION DENSITY**

**REPRODUCTIVE POTENTIAL**

## REPRODUCTIVE

**REPRODUCTIVE**
**   ****POTENTIAL**

**CLUTCH**

**    ****FREQUENCY**

**AGE/SIZE**

**AT**

**SEXUAL MATURITY**

**  ****LONGEVITY**

**CLUTCH SIZE**

##      HUMAN RELATED IMPACTS UPON

**      ****DESERT TORTOISE POPULATIONS**

**TORTOISE**

**AGRICULTURE**
**COLLECTION**
**DESERTIFICATION**
**DUMPS/LANDFILLS**
**EXOTICS**
**FIRE**
**GRAZING**
**GENETIC ISOLATION**
**HABITAT**
**    ****FRAGMENTATION **
**MINING**

**NOISE**
**OHV’S**
**POLLUTION**
**RECREATION**
**RELEASE OF **
**     ****CAPTIVES**
**RESEARCERS**
**ROADS**
**SHOOTING**
**URBANIZATION**

## Slide 11

##     From:  S. Payne. 1974. Terrestrial model:  Animal Processes (Version III).  U.S. IBP Desert Biome Report

**    ****From:  S. Payne. 1974. Terrestrial model:  Animal Processes (Version III).  U.S. IBP Desert Biome Report**

## Desert

**Desert**
**Tortoise**
**Population**

**Abiotic**
**Factors**

**Ephemeral**
**Plants**

**    ****Tortoise**
**Reproduction**

**Parasites**
**Diseases**

**Natality**

**Mortality**

**Decomposers**