Deer vigilance and movement behavior in response to edge density and connectivity

Animal behavior is an important component of individual, population, and
community responses to anthropogenic habitat alteration.  For
example, antipredator behavior (e.g., vigilance) and animal movement
behavior may both be important behavioral responses to the increased
density of habitat edges and changes in patch connectivity that
characterize highly modified habitats. Importantly, edge density and
connectivity might interact, and this interaction is likely to mediate
animal behavior: linear, edge-rich landscape features often provide
structural connectivity between patches, but the functional connectedness
of patches for animal use could depend upon how edge density modifies
animal vigilance and movement. Using remote cameras in large-scale
experimental landscapes that manipulate edge density (high- vs.
low-density edges) and patch connectivity (isolated or connected patches)
we examined the effects of edge density and connectivity on the
antipredator behavior and movement behavior of white-tailed deer
(Odocoileus virginianus).  Deer vigilance was 1.38 times greater
near high-density edges compared to low-density edges, regardless of
whether patches were connected or isolated.  Deer were also more
likely to move parallel to connected high-density edges than all other
edge types, suggesting that connectivity promotes movement along
high-density edges. These results suggest that increases in edge density
that accompany human fragmentation of existing habitats may give rise to
large-scale changes in antipredator behavior of deer. These results also
suggest that conservation strategies that simultaneously manipulate edge
density and connectivity (i.e., habitat corridors) may have multiple
effects on different aspects of deer behavior: linear habitat corridors
were areas of high vigilance, but also areas where deer movement behavior
implied increased movement along the habitat edge.