|
be where
a mixed hardwood forest meets an open pasture or a mature forest meets a
thicket or a young forest.
The
reason that edge is so important to wildlife is that most wildlife
species depend on more than one habitat type to meet their basic needs
of food, cover, water, and space. Food must be present throughout the
entire year. Cover is needed for things such as resting, escaping
predators, protection from bad weather and nesting or the rearing of
young. Water doesn’t always have to be in the form of ponds, lakes or
streams. Sometimes an animal can obtain moisture from the food that it
eats or, in the case of some birds and small mammals, by drinking
dewdrops. The amount of space needed varies widely from one species to
the next.
In
most cases, a single habitat type can meet one or possibly two of these
requirements but usually not all of them. In some cases a particular
habitat may meet certain requirements only during a particular time of
year. For example, a mature oak forest may provide an abundance of
acorns, an excellent food source for white-tailed deer during the fall,
but little other food is available during the rest of the year. A large
soybean field can seasonally provide an abundance of food; but often
times, little cover is available in the center portions of the field
which results in most species being unable to utilize that food.
Typically,
as you increase the number of habitat types in a given area and the
total amount of edge between them, you also see an increase in the total
numbers of a particular species that can utilize the area. In addition,
this change tends to also increase the total number of different species
that the area can support. This phenomenon is commonly known as the
"edge effect."
The
edge effect is most pronounced in species that have small home ranges,
such as bobwhite quail, rabbits and some species of songbirds. These
animals typically have home ranges that cover only a few acres. Animals
such as white-tailed deer, wild turkey and black bears require less edge
per unit of area because of their larger home ranges. A large home range
allows these animals to move greater distances to find the habitat types
necessary to meet their basic biological needs.
Edge
and the effects that it produces are important to anyone interested in
managing for wildlife — from homeowners who are interested in creating
a small backyard habitat for bird watching, to the avid hunter
interested in improving his property or leased lands for white-tailed
deer, turkey or quail.
Interspersion
of different habitat types and the edges that they create are key to
successfully establishing and maintaining healthy and abundant wildlife
populations.
For
more information on creating or enhancing wildlife habitats, please
contact Ron Eakes, Wildlife Biologist, Wildlife and Freshwater Fisheries
Division, 21438 Harris Station Road, Tanner, AL 35671. |
