Interactive Dynamics of Wildlife Populations, Human Health and - - PowerPoint PPT Presentation

▶
interactive dynamics of wildlife populations human health
SMART_READER_LITE
LIVE PREVIEW

Interactive Dynamics of Wildlife Populations, Human Health and - - PowerPoint PPT Presentation

Oct 26, 2022 164 likes •364 views

Interactive Dynamics of Wildlife Populations, Human Health and Household Wealth Matthew D. Potts mdpotts@berkeley.edu www.pottsgroup.org 1 Objectives Illustrate that the inclusion of human health in simple bioeconomic models of wildlife

slide-1
SLIDE 1

Interactive Dynamics of Wildlife Populations, Human Health and Household Wealth

Matthew D. Potts mdpotts@berkeley.edu www.pottsgroup.org

1

slide-2
SLIDE 2

Objectives

  • Illustrate that the inclusion of human health in

simple bioeconomic models of wildlife harvesting can significantly alter model behavior.

  • Demonstrate the functional form of feedbacks

matter in models of coupled natural human systems.

slide-3
SLIDE 3

Acknowledgments

  • Collaborators: Elaina Marshalek, Ryan Marsh,

Samuel Evans, Lauren Withey

  • Biodiversity, Health and Livelihoods

Team: Berkeley, Tanzania, Madgascar & Ghana

  • NSF Funding: GEO-115057, CNH: Interactive

Dynamics of Wildlife Populations, Human Health and Household Wealth in Rural Africa.

3

slide-4
SLIDE 4

Biodiversity & Livelihoods

Wildlife is the primary source of animal protein and income for more than 1 billion people (Milner-Guilland et. al. 2003).

4

How do we identify feasible strategies to improve peoples livelihoods and conserve biodiversity?

  • J. Brashares
  • J. Brashares
slide-5
SLIDE 5

Wildlife Consumption & Wealth Distance to Wildlife Effects

5

Biodiversity & Livelihoods

Research has clearly demonstrated linkages between wealth, income and wildlife consumption.

slide-6
SLIDE 6

Biodiversity & Health

Global Anemia Prevalence

6

slide-7
SLIDE 7

Impact of Bushmeat on Hemoglobin

Bushmeat could contribute app. 60-80% of what iron supplements accomplish If access to bushmeat is lost, there will be a 30% increase in the incidence of anemia

  • C. Golden - Madagascar

7

Biodiversity & Health

slide-8
SLIDE 8

Biodiversity, Health & Livelihoods

Guiding Questions

  • How does the inclusion of health in

bioeconomic models of wildlife harvesting effect wildlife population dynamics and

  • verall household well-being?
  • What impact does the inclusion of health

effects have on management strategies aimed at either conserving wildlife or improving overall household well-being?

8

slide-9
SLIDE 9

Modeling Approach

  • Track utility and nutritional status of a “representative” subsistence

household in a developing country.

  • In each time period, households allocates labor to hunting and

agriculture so as to maximize utility in that period (not forward looking).

  • Nutritional status determines total amount of labor available and is

updated period to period.

  • Wildlife population follows logistic growth with off take determined by

hunting activity.

  • Human population growing through time.
  • Wildlife population goes extinct when population falls below 20% of

carrying capacity.

9

slide-10
SLIDE 10

Twelve Model Variations

Labor dependence on nutritional status

I. No impact

  • II. Impacts total labor
  • III. Impacts total labor & farm

labor

Management Interventions

I. None (NM)

  • II. Improve agricultural yields (Ag)
  • III. Conserve game (G)
  • IV. Restrict access to game & improve

agricultural yields (Ag & G)

10

X

slide-11
SLIDE 11

Nitty Gritty Model Details

Key Variables Utility Function Constraints State Equations Labor State Equations

11

slide-12
SLIDE 12

Results

(Implemented & Solved in GAMS)

12

slide-13
SLIDE 13

Time

13

Labor Allocation

Management Intervention

None Increase Ag Conserve Game Ag & Conservation

Labor dependence on nutritional status

No Impact Total Labor Total & Farm Labor Time

Both health effects & management interventions alter patterns of labor allocation.

100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0

Farm labor Hunting

slide-14
SLIDE 14

Time

14

Nutrition Value

Management Intervention

None Increase Ag Conserve Game Ag & Conservation

Labor dependence on nutritional status

No Impact Total Labor Total & Farm Labor Time

100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0 100 200 300 400 0.0 0.2 0.4 0.6 0.8 1.0

Management intervention do improve health in short run.

slide-15
SLIDE 15

Time

15

Time to Collapse of Game Population

Management Intervention

None Increase Ag Conserve Game Ag & Conservation

Labor dependence on nutritional status

No Impact Total Labor Total & Farm Labor Time

100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500 100 200 300 400 100 200 300 400 500

Conserving game with health effects does not prevent game collapse.

slide-16
SLIDE 16

Conclusions

  • Incorporation of nutritional status and linking it

to labor availability and allocation can dramatically change the time to extinction of wild game species.

  • Efficacy of management interventions depends
  • n assumptions about household health and

labor allocation.

16

slide-17
SLIDE 17

General thoughts on modeling coupled natural-human systems

Two Key Issues

  • Feedbacks
  • Mean vs.

Variance

slide-18
SLIDE 18

Thank You! Questions?

18