Angela Watkins Jason Noble and C. Patrick Doncaster.

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An agent-based model of jaguar movements through conservation corridors Angela Watkins Jason Noble and C. Patrick Doncaster

Transcript of Angela Watkins Jason Noble and C. Patrick Doncaster.

Page 1: Angela Watkins Jason Noble and C. Patrick Doncaster.

An agent-based model of jaguar movements through

conservation corridorsAngela Watkins

Jason Noble and C. Patrick Doncaster

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Background Aims Methodology The Model Results Conclusion Current Work

Order of Events

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Background

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The most important threats to global biodiversity

Less habitat means fewer individuals

Populations become increasingly isolated

Habitat loss and fragmentation

Pictures taken from advocacy.britannica.com, dailyreckoning.com.au, king.portlandschools.org

respectively.

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Connect local sub-populations Reduce the risk of local extinctions

Effective conservation requires the description of a landscape from an

individual species’ perspective in order to measure, understand and conserve

‘functional habitat connectivity’

Corridors, Connectivity and Conservation

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Largest cat in the Americas, third largest in the world

Apex predator and keystone species Territorial and solitary Preferred habitat:

◦ Tropical rainforest◦ Subtropical rainforest

Jaguar

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Jaguar range

Historic Range

Current Range

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Link between two protected areas

Critical area linking populations to the north and the south

Subject to urban expansion

Central Belize Corridor

Jaguar Corridors

Jaguar Populations

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Aims

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Build a simple agent-based model of jaguar movement

Explore the effect of landscape structure on the population

Investigate how corridors can connect discrete habitat patches

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Methodology

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Individual agents represent individual organisms

Interactions between individuals

Interactions between individuals and the landscape

Agents encoded with rules that mimic simplified real behaviours

Agent-based simulations

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Least-cost models

Habitat maps used to ‘cost’ the landscape

Species-specific

‘Organisms use a route of least resistance’

Taken from: Rabinowitz, A. & Zeller, K. A. (2010) A range-wide model of landscape connectivity and conservation for the

Jaguar, Panthera Onca. Biological Conservation 143: 939-945.

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The Model

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Model landscapes

3 controls

3 non-connected

3 connected

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Cost Values

Habitat Cost

Forest 1

Edge 5

Non-forest 25

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9-cell Moore neighbourhoods

Sex-specific movement rates◦ Males - 100%, females – 70%

Sex-specific territoriality◦ Pheromones add a cost to the cell

5% random moves

Model parameters

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Results

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Clearly identified territories and habitat choice

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No strong difference in average landscape cost value

Map Layout

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Connected corridors promote movement between patches

Map Layout

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Conclusions

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Plausible territorial behaviour

Not all corridors are the same

Critical feature for cost: amount of habitat

Key difference:

capacity to promote migration from one patch to another

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Current Work

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Integrate model with real-world GIS data Validate agent movement with empirical

data

Aims

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Least-cost route choice Pheromones Male preference for trails Female avoidance of males? Difference in movement inside vs.

outside Cockscomb? Male vs. female movement rates

Key Parameters

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SupervisorsJason Noble and C. Patrick Doncaster

Jaguar Corridor InitiativeBart Harmsen and Rebecca Foster

This work was supported by an EPSRC Doctoral Training Centre grant (EP/G03690X/1).

Acknowledgements

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Any questions?