The Interactions between Landscapes and Individuals

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The Interactions between Landscapes and
Individuals Behaviors associated with spatial
properties of environments 1) Foraging 2)
Habitat Selection 3) Reproductive Strategies 4)
Inter-individual interactions Is any of this
appropriate to nonanimals?
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Foraging Ecology The Holling disk equation
Holling, C. 1959. Canadian Entomology 91
385-398
What variables might be affected by spatial
properties of landscapes?
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The Marginal Value Theorem Charnov, E. 1976.
Optimal foraging theory the marginal value
theorem. Theoretical Population Biology
9129-136 How to pick a patch and when to leave
it 1) Assume random movement within a patch with
a finite number of prey
Cumulative Reward
Time in patch
Slope of tangent to curve is instantaneous reward
rate - When does it pay to leave?
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How does the distance between patches affect time
spent within a patch? Potential value of a patch
is
Cumulative Reward
tt
0
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Nonrandom within patch search?
Cumulative Reward
Factors which affect tt Optimal search patterns
(spanning trees) Spatial memory Cognitive
maps Other ecological processes, predator
avoidance, mating system, territory management
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Effect of patch density on average travel time
between randomly dispersed patches
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Search Paths
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Relationship between Variogram and Fractal
Dimension
slope m0, D2
slope m1.8, D1.1
ln (variogram(h))
slope m2, D1
ln(h)
Limits to Fractal dimensions D Process 1-2 traces
or paths 2-3 surfaces or maps 3-4 volumes or
objects
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Patterns of Habitat Utilization Swihart and
Slade. 1985. Testing for independence of
observations in animal movements Ecology
1176-1184. Swihart, Slade, Bergstrom 1988.
Relating body-size to the rate of home range use
in mammals. Ecology 69 393-399.
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Behavior and Ecological Landscapes

• Information about the landscape and used by the
  individual
• Evolved knowledge i.e., adaptation to landscape
  features
• Perception and information gathered
• Scale of information
• Rules for movement are there optimal rules?

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An Individuals Landscape
But See Robinson and Falls. Robinson, W. L. and
Falls, J. B. 1965. A study of homing of meadow
mice. American Midland Naturalist 73 188-224.
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Effect of Perceptual Landscape on Dispersal
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Applying this to real organisms Zollner and
Nudds model Fox and Grey squirrels in
Illinois Fox squirrels have larger perceptive
range than greys. Fox squirrels are found in
isolated woodlots, greys usually are not.
Presence of powerlines and/or fencelines were
quite important Corridors?
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Butterfly turn angles from Haddad 1999. American
Naturalist