INTEGRATING DISEASE INTO POPULATION VIABILITY ANALYSIS

(Leah Gerber, Andy Dobson, Kevin Lafferty)

Introduction (LEAH)

Disease is important for Conservation

PVA has ignored disease

Key concepts in PVA (LEAH)

Demographics

Variation in abundance over time

Sensitivity analysis

Management actions

Threats

Vital rates

Survival

Reproduction

Emmigration/Immigration

Key concepts in Epidemiology (KEVIN)

Deterministic approach

Host density threshold

Target host

Intermediate host

Effect of generalist/reservior

Change in resistance (genetic diversity/pollution)

Change in parasite vital rates

Change in parasite death

Change in infected host death

How has disease been incorporated in PVAs (ANDY/LEAH?)

% with disease

stochastic treatment

need to include our knowledge of disease dynamics for more precise predictions

 

Model Exercise (not sure we will do this?)

Deterministic vs stochastic or no treatment of disease

Relative Allee’s

Frag vs Degrade

Generalist vs specialist

Impacts (pollution, etc.)

Does disease increase or decrease range of uncertainty?

Less uncertain, more precise predictions of time to extinction, therefore more useful for conservation decisions

Random mortality variable drawn from uniform distribution (no data, but disease), No random draw (no disease), disease cycles are known/deterministic ??

Case Study (ANDY?)

Real example of PVA created for a species where disease is a likely issue

 

 

NOTES FROM ANDY:

Assess vulnerability to disease using PVA

Emphasize use of PVA in asssessing management actions relative to disease

How to specify a detailed module for pathogens – need data on population effects of disease

Categorize disease effects on different taxa

Simple way to include disease in models?