Habitats
Habitats: A Fact Sheet Series on Managing Lands for Wildlife
University of Maine Cooperative Extension Bulletin #7132
Principles for Creating a Backyard Wildlife Habitat
It’s easy to create a landscape for your own enjoyment and, at the same time, provide for the needs of wildlife. This fact sheet will introduce you to nine principles that will help you do just that: the four basic wildlife needs; function and form; diversity; seasonality; arrangement; protection; native plants and seed origins; climate and plant hardiness zones; and soils and topography.
The Four Basic Wildlife Needs: Food, Water, Cover and Space
Food: Food supplies energy and nutrients. Each wildlife species has its own nutritional needs, which change from one season to another and as an individual animal goes through its life cycle. Your plantings can provide a variety of foods, such as fruits and berries, grains and seeds, nuts and acorns, browse plants which include twigs and buds of shrubs and trees, forage plants which include grasses and legumes, and aquatic plants. Insects and other invertebrates, attracted to flowers, shrubs and trees, are also food for wildlife. Grit is used by many birds as part of their digestion. Flowering plants first provide nectar, then seeds or fruits. In some instances, the same plants hold their seed or fruit into fall or winter.
Profile: Alternate-leaf Dogwood
Alternate-leaf dogwood (Cornus alternifolia) flowers provide nectar for insects. Fruit and buds are used by many bird species and some mammals. This plant is also used for shelter and nesting by birds.
Water: This is essential to all forms of life. If you have a watery habitat on your property, preserve it. If not, consider how you might provide water. You might create a pond or use birdbaths as a source of water in your yard. Heated birdbaths provide water when most other sources are frozen. Food provides some of the water necessary to wildlife, but a good drink of clean water is always welcome. Birdbaths should be no more than three inches deep, and have a rough, sloping bottom to provide good footing.
Cover: Trees, shrubs, grasses and flowering plants provide shelter or cover for wildlife, as do rock piles, brush piles, cavities in trees and birdhouses. Wildlife use cover to protect themselves from the elements, to hide from predators and to rest or sleep. They also use cover for nesting and rearing their young.
Space: Many species of wildlife are territorial, defending an area that contains the food, water and cover they need. Species that are not territorial occupy a home range within which they perform daily functions and find food, water and cover. The amount of space needed for a territory or home range varies with the species, the quality of the habitat and the time of year. Have you noticed that many birds are solitary or paired in summer and flock together in winter? Keep in mind that territories and home ranges may include, but often extend beyond, your yard.
Function and Form
When choosing plants for your yard, consider their function or role, as well as their form or appearance. Ask yourself, "Will it provide food or shelter, will it add to the diversity of the habitat?" You may have limits as to what you can plant because of the size of your yard or the cost, so choose plants that serve more than one function.
Diversity
Diversity or variety in your habitat will promote a healthy landscape and attract diverse wildlife species. Aim for plant species and structural diversity, as well as a variety of non-living materials.
Plant species diversity: The presence of many plant species makes it less likely that insects or disease will cause severe problems. Having many species of trees, shrubs, perennial and annual flowers and grasses in your yard will also attract more varied wildlife. Diverse plants provide a wide range of foods that are available throughout the year.
Plant structural diversity: The shape and size of different plants combine to create structure in your landscape horizontally and vertically. Horizontal structure, side-to-side, can be thought of in terms of edges, those places where one habitat type meets another, such as a lawn meeting a line of trees. You can increase the diversity of the edge by widening the ecotone, the zone of transition between habitat types. For example, you could plant small shrubs such as butterfly bush, tall shrubs such as serviceberry, and small trees such as crabapple to the edge between a lawn and a line of trees, as shown in the illustration. You can widen the ecotone in a flower garden by planting species of increasing heights. This may be low-growing plants, such as sedum and marigolds, in front of medium height plants, such columbine and liatris, with tall plants, such as phlox and yarrow, located behind.
You can add to the vertical diversity of your landscaping by adding more layers of vegetation between the ground and the tree tops. Wildlife species that feed, nest or find shelter at different levels will be able to meet their needs. Vertical diversity may be added by enhancing the ecotone, as already described, or by planting species of varying heights and growth habits in arrangements that are appealing to you. Of course, you will use plants appropriate to the scale of your yard.
Diversity of non-living materials: There is more to wildlife habitat diversity than living plants. Standing or fallen dead trees provide cavities, food and perches. Brush piles and rock piles or stone walls provide hiding, nesting and feeding sites. Grit and dust baths are used by birds to aid digestion and keep clean. Buildings provide nest sites and perches, and places for butterflies and moths to hibernate. Nest and winter roosting boxes can be erected to supplement natural cavities, and feeders add to the food supply. Water, in any form, is essential.