| dc.description.abstract | Animal travel between habitat patches affects populations, communities and ecosystems.
There are three levels of organization of edge properties, and each of these can affect
animals. At the lowest level are the different habitats on each side of an edge, then
there is the edge itself, and finally, at the highest level of organization, is the
geometry or structure of the edge. This study used computer simulations to (1) find out
whether effects of edge shapes on animal behavior can arise as emergent properties
solely due to reactions to edges in general, without the animals reacting to the shapes
of the edges, and to (2) generate predictions to allow field and experimental studies to
test mechanisms of edge shape response. Individual animals were modeled traveling inside
a habitat patch that had different kinds of edge shapes (convex, concave and straight).
When animals responded edges of patches, this created an emergent property of responding
to the shape of the edge. The response was mostly to absolute width of the shapes, and
not the narrowness of them. When animals were attracted to edges, then they tended to
collect in convexities and disperse from concavities, and the opposite happened when
animals avoided edges. Most of the responses occurred within a distance of 40% of the
perceptual range from the tip of the shapes. Predictions were produced for
directionality at various locations and combinations of treatments, to be used for
testing edge behavior mechanisms. These results suggest that edge shapes tend to either
concentrate or disperse animals, simply because the animals are either attracted to or
avoid edges, with an effect as great as 3 times the normal density. Thus edge shape
could affect processes like pollination, seed predation and dispersal and predator
abundance. | en_US |
