“Our ability to perceive quality in nature begins, as in art, with the pretty. It expands through successive stages of the beautiful to values as yet uncaptured by language.” Aldo Leopold
No doubt, by creating a landscape that offers the same utility to wildlife as natural habitat, you will enjoy a greater diversity of wildlife species year around. But the real satisfaction is coming to understand the components of wildlife habitat and how wildlife depend those components. By coming to understand wildlife habitat, you will learn firsthand, and hands on, how to comprehend land from wildlife’s perspective. You will become an ecologist in every sense of the word.
An urban wildlife habitat should accomplish two things. It should meet your needs, such as aesthetics, maintenance and cost, as well as meet the needs of wildlife: cover, food, water and space.
Understanding Cover for Wildlife
The importance of cover to wildlife is often overlooked but cannot be understated. Sufficient cover allows animals to avoid predators and offers safe places for nesting, brooding or avoiding inclement weather. Escape cover for birds, for instance, should be dense and close to where they access food or water. Nesting cover varies. It might dense vegetation for ground-nesting species like Canada geese or killdeer. For cavity nesters like wrens, bluebirds or wood ducks, standing dead trees or artificial nesting boxes can offer nesting cover. Brooding cover is critical for species like bobwhite quail, ruffed grouse and wild turkey, whose young are mobile and must forage for insects as soon as they hatch. In essence, cover types are structurally different and wildlife use them in different ways. In most urban cases escape cover should be the focus: consider a food source like a single bird feeder; that feeder will concentrate birds, and predators will quickly learn to focus on that location. If the feeder is close to adequate escape cover, it will be more heavily used by birds, since they can quickly dive into the safety of brush before a predator can close the deal.
The arrangement of cover also matters. Cover should be multi-dimensional; that is, diverse horizontally across your landscape and diverse vertically from understory to mid-story to tree canopy.
Different species of wildlife, birds in particular, will utilize different vertical levels of vegetation. Species such as sparrows and wrens spend most of their time within ten or fifteen feet of the ground, whereas some species, like the threatened cerulean warbler, generally stay high in the canopy. Providing different levels of vertical vegetation – vertical diversity – will make your habitat desirable to more species.
Forest openings create horizontal diversity by breaking up mature forests, creating diversity across the landscape. Forest openings like fields and meadows are areas where the most sunlight reaches the ground and allows
grasses and broad-leafed forbs to flourish, offering excellent cover and a storehouse of seeds and protein-rich insects. Species like the eastern meadowlark, purple martins, swallows and flycatchers depend on these areas. Openings also create valuable edge habitat. You’ll notice also that unmanicured forest openings, like fallow fields or powerlines, do not have a crisp transition from grass to forest. Instead the vegetation is very dense along the edge. The transition from knee-high grass and weeds, to thick saplings and vines, to mature forest, is gradual. That gradual, layered transition from one habitat type to another is called an ecotone and is heavily favored by wildlife.
Cover for Wildlife in your Landscape
In your lawn, hedge rows and beds of dense vegetation can offer ideal escape cover for wildlife and be an appealing profile to you landscape design. Vegetated fence rows are another opportunity to incorporate cover for wildlife.
When deciding on what to plant as a hedge row, consider whether or not the plants will offer sufficient cover year around. For instance, hydrangeas and some Virburnum species, which are common deciduous ornamentals, offer great cover during the summer but poor cover during the winter (though, that’s not to say they should never be planted). American hollies are native evergreens, regularly used as ornamental hedges, and offer excellent cover year-around. Other ideal hedge plants include Eastern red cedar, Japanese honeysuckle and wax myrtle, all of which offer a food source as well.
Keeping “soft edges” on hedge rows enhances the hedge’s utility as escape cover, while tightly trimmed hedge rows are slightly more difficult for birds to penetrate quickly into the safety of the branches. In addition, thorny plants such as blackberry present even more of an impediment to would-be predators.
There are numerous native plant species that are attractive landscaping specimens and valuable to wildlife. Using native plant species has several benefits. Native species, being already adapted to your region’s climate will require little or no watering, fertilizer or other special care. In addition, native wildlife is generally adapted to seeking out native food items. Referring to the resources at the end of this article, as well as consulting a local plant nursery, preferably one that offers native plant species, will give you a lot of options and allow you to use your own creativity.
Many wildlife species depend on standing dead trees for both food and cover. However in urban settings, dead trees are most often removed to reduce liability and enhance aesthetics; if you can leave a few, do so. If not, offering nesting boxes for cavity nesters can help offset the deficit of natural cavities. Nesting boxes should face away from each other to
avoid competition (female blue birds for instance can be wildly aggressive if the openings face each other). Many commercial bird houses are available, but metal or plastic bird houses should be avoided, as they tend to retain heat more than wooden boxes which can lead to “cooked nests”.
If possible, a portion of your landscape should be converted to a tall, grassy,meadow-type habitat. The grass should be mowed or weedeated downtwice a year, once in early summer and again in late summer, to reset natural succession and discourage woody plant vegetation. One drawback in many urban settings is that unmowed grass suggests a neglected lawn. However, by thoughtfully orienting and mantaining your meadow habitat you can create an aesthetically pleasing layer to your landscape’s arrangement. Dispersing native wildflowers among the grass
will add a splash of color to your landscape as well as attract butterflies and hummingbirds. A few native, low maintenance wildflower species to consider include:
- Black-eyed Susan
- Purple coneflower
- Butterfly weed
- Standing cypress
- Sage (Salvia coccinea)
- Cardinal flower
- Sweet goldenrod
Food for Wildlife
Food items should be diverse and available year around. Incorporating plants that produce fruit at different times of the year will ensure that wildlife are able to meet nutritional demands even during stress periods such as late winter. It is convenient that many plant species that offer great cover for wildlife also offer excellent food sources. This can save space in your yard and keep food and cover close together. Native plant species should be the first resort. A few attractive, native (to the southeast) species of fruiting trees and shrubs that will provide food from mid-summer will into fall include American Beautyberry, Hearts-A-Busting, Dogwood, Black Cherry and Sugar Berry. As a winter food source, consider American Holly and Eastern Red Cedar. Again, there are a lot of options depending on your region and soil conditions so researching and consulting plant nursery will allow you to determine which plant species are best for your landscape.
Insects are equally important food items. This is where your meadow type
habitat can play a crucial role since the tall grass holds more insects than short mow. Amply higher in protein than fruits, insects are a critical part of birds’ diet, especially during the spring when females rely on insects to feed their rapidly growing young who require a protein-rich diet. Some species, such as wrens, most warblers, phoebes, great-crested and blue-gray flycatchers prefer insects year-around. During the summer months you will likely notice bats feed just above these areas to glean small insects that spend the hottest
hours of the day among the cover of tall grasses. Tall grasses largely benefit insects in the order Orthoptera, which includes crickets, grasshoppers, katydids and more. Insect pests such as mosquitoes, roaches and termites will not be similarly encouraged by tall grass.
Warblers are brilliantly colored species that migrate back and forth over the southeast from their wintering grounds in the neo-tropics to their breeding grounds in the northeastern US and Canada. They are also habitat specialists, meaning that they prefer specific habitat types, especially specific food items, as opposed to most resident backyard bird species who are habitat generalists. Warblers are almost exclusively insectivorous and especially benefit from vertical diversity. Tree species such as oak and beech generally offer more caterpillars than other tree species and will be more attractive to warblers than a bird feeder. Warbler sightings can be an indicator of how successful your backyard habitat is, but not always.
Feeders can be an excellent supplementary food source, especially during winter when both vegetable and animal food items are hard to come by. But
feeders have their drawbacks and should be a supplement to, not a substitute for, wild food items. Feeders concentrate birds, provoking aggression within and among species as well as making them more vulnerable to predators. Using several feeders, placed at different heights and in different parts of your landscape can decrease competition and, of course, placing them close to escape cover can decrease predation. The most common types of seed available are millet, black oil sunflower and thistle seed. Blends, usually containing peanuts, black oil sunflowers and millet, are not bad but offering those seeds separately in different feeders can help to curtail competition since different species often prefer different types of seed. For finches, Niger or thistle seed is preferred to all other seeds. Suet, a mix of fat, seeds and nuts can be an excellent supplement. Suet is high in protein and energy and will often attract birds that are typically insectivorous, especially during winter when insects are not as abundant. Move your feeders every few weeks to avoid a build-up of droppings beneath the feeder which can represent a health hazard.
Be judicious with pesticides. While mosquito and fire ant control can be a reasonable objective, consider that if an insecticide kills mosquitoes or fire ants it is likely just as toxic to other insects. Bifenthrin is a very effective insecticide and one of the most common active ingredients in over-the-counter insecticides. Bifenthrin is not a selective insecticide and if it is applied indiscriminately all non-target insect species are effected. Bifenthrin’s impact on the declining honeybee population is of considerable concern. To control fire ants, consider applying the insecticide directly to nests (in accordance with application directions), as opposed to broadcasting evenly over the lawn.
Water should always be nearby. A natural water source like a creek or pond is ideal because they require little or no maintenance and will always provide fresh water. Artificial water features are great as well, though they’re often expensive to install. Bird baths work perfectly well as long as the water is changed every few days. If you have the space, offering two or three bird baths can decrease competition by providing more of the resource. Again, keep the baths close to escape cover.
If you are lucky enough to have a natural water source connected to your landscape you may have additional wildlife viewing opportunities, as some species like belted kingfishers, hooded warblers, prothonotary warblers, great blue herons, etc. require natural water sources. Preserving dense vegetation along the bank will encourage wildlife to visit, reduce erosion, and preserve water quality by naturally filtering runoff.
Space is another important wildlife habitat component. The amount of space an animal needs depends largely on how far it has to travel to meet its daily nutritional requirements. The area an animal travels on a daily basis to meet those demands is called its home range. For migratory species, home range can include tens of thousands of miles; for a whitetail deer a few hundred acres can be sufficient; for a robin or sparrow, just a few acres might do. When food, water and cover are close by, wildlife needn’t travel as far to meet their nutritional demands. Most urban landscape initiatives are restricted to relatively small property boundaries, so getting neighbors involved in wildlife friendly landscaping might increase desirable habitat size from a few small disconnected properties to a large, subdivision-wide wildlife initiative.
Fertilizers, while frowned upon by some “experts”, can be an asset. Applied properly, fertilizer has been shown to increase the nutritional quality, abundance of vegetation and fruit production, palatability, and digestibility of many plant species. However, applied improperly, fertilizer can lead to compromised water quality and other environmental concerns, not to mention the cost. Fertilizer should only be applied in accordance with the results of a soil test. There are numerous facilities that offer soil analysis at a negligible cost, as well as easy-to-follow online resources for interpreting the results from your soil test.
Urban Wildlife and Predation
When you have created your wildlife habitat, you will have created a place where wildlife is likely to congregate, and as prey congregates, so do predators. Some predation is inevitable, however offering sufficient cover will keep the playing field level between predator and prey. In many cases, pets are the main predators of urban wildlife.
Finally, enjoy getting dirt under your fingernails and working with the landscape, not against it. Remember that in the end, your initiatives are well conceived and will likely add up to more than just good intentions.
Hunter S. Bridges