dwyer SAC 2005 v2

Ecological Models and Ecosystem Health: 

Ecological Models and Ecosystem Health Greg Dwyer, Cathy Pfister, Tim Wootton, Bret Elderd, Mei Wang, Marc Coram, and Vanja Dukic Although the research described herein has been funded wholly or in part by the United States Environmental Protection Agency through STAR Cooperative Agreement #R-82940201-0 to the University of Chicago, it has not been subjected to the Agency’s required peer and policy review and therefore does not necessarily reflect the views of the agency, and no official endorsement should be inferred.

2003-2008 US EPA Strategic Plan: 

2003-2008 US EPA Strategic Plan Goal 4: Healthy Communities and Ecosystems 4.1: Identifying and assessing potential risks from chemicals, pesticides, and microorganisms. 4.2: Sustain, clean up, and restore communities and the ecological systems that support them 4.3: Protect, sustain, and restore the health of natural habitats and ecosystems. 4.4 Enhance science and research.

EPA FY2004 Annual ReportGoal 4 Strategic Objectives: 

EPA FY2004 Annual Report Goal 4 Strategic Objectives Prevent and reduce pesticide, chemical and genetically-engineered biological risks to humans, communities and ecosystems. Protect, sustain, and restore the health of natural habitats and ecosystems.

CISES Ecology Group Projects: 

CISES Ecology Group Projects Matrix Population Models and Ecological Stressors: Cathy Pfister, Mei Wang, Bret Elderd Disease Dynamics & Ecosystem Health: Greg Dwyer, Marc Coram, Vanja Dukic, Bret Elderd Complex Effects in Ecosystems: Tim Wootton, incoming post-doc

Population Growth and Stressors: 

Population Growth and Stressors Are stressors causing population declines? Approach: estimate changes in l due to stressors, project population size

Structured Population Models: 

Size-Structured Population Model Structured Population Models

Structured Population Models: Publications: 

Structured Population Models: Publications Pfister, C. and M. Wang. Beyond size: the demographic impacts of individual variation in growth rates. Accepted pending minor revision at Ecology. Elderd, B and D. Doak. Using matrix models to quantify effects of human disturbances on plant populations. In review, Ecol. Letters. Sun, L. and M. Wang.  An algorithm for a decomposition of weighted digraphs: with applications to life cycle analysis in ecology. In review, Journal of J. Math Bio. G. Dwyer and W.F. Morris. Resource-dependent movement and the spread of biological invasions. In revision at The American Naturalist

Partial Life-Cycle Models & EPA: 

Partial Life-Cycle Models & EPA Collaborators: Bret Elderd, CISES, & Jason Grear, USEPA, Atlantic Ecology Division. Basic idea: How much explanatory power do we lose if we have only a rough idea of how survival and fecundity vary with ages or stages? Applications: mercury exposure in loons, PCB exposure in intertidal fish.

Species Interactions and Ecosystem Health: 

Species Interactions and Ecosystem Health Are species interactions changing due to human activities? Approach: estimate changes in a12 due to stressors or other anthropogenic effects, project population sizes

Slide10: 

Simple Epidemic Model Virus particles Uninfected Hosts Infection Death or Recovery If S(0) > g/b, an epidemic occurs

Disease Models & EPA: 

Disease Models & EPA Contacts: Anne Fairbrother, Jennifer Orme-Zavaleta, Western Ecology Division, USEPA, Corvallis, OR Applications: Emergent diseases, including chronic wasting disease and West Nile virus

Multispecies Models in Ecology: Sensitivity Analysis: 

Multispecies Models in Ecology: Sensitivity Analysis Deterministic Model a12 Predictions as affected by variability in a single parameter a21 a22 a22 Point Estimates of params { Vary one param by, say, +/- 20%

Multispecies Models in Ecology: Bayesian Approach: 

Multispecies Models in Ecology: Bayesian Approach Likelihood Of Stochastic Model a11 Distribution of predictions a21 a22 a12 Priors {

Multi-Species Models, Present and Future: 

Multi-Species Models, Present and Future Today: Vanja Dukic: A Bayesian Approach Marc Coram: Stochastic Disease Models Future: Tim Wootton and incoming post-doc: many-species models Population Growth and Stressors: Bret Elderd: Partial life-cycle models