“Is the deer crossing the road, or is the road crossing the forest?”
To survive, most wild fauna must be on the move—to find food, water, safe shelter and breeding sites, mates, and, for some species, to migrate. But wildlife habitat is increasingly destroyed, degraded, or fragmented into small, isolated patches—by human-made barriers such as buildings, fences, lawns, and roads—which intensify their struggle to survive.
Habitat loss is one of the main threats to wildlife. More people and development mean less natural habitat, while inaction on the climate crisis forces animals to relocate. Today, more than ever, habitat connectivity needs to be restored and wild ones’ daily and seasonal movements or migrations protected.
Habitat connectivity is defined as the degree to which the landscape helps or hinders animals’ movements, as well as other ecological processes, such as seed dispersal. Whether they’re called conservation corridors, green corridors, habitat corridors, or wildlife pathways, their purpose is identical: To provide native habitat as seamlessly as possible, so that wildlife populations may be connected instead of separated. Even in deteriorated landscapes, such corridors boost biodiversity, allow genetic exchange between populations, and may even help ease the reestablishment of populations that have been decimated, isolated, or previously extirpated.
Recognizing that every front, back and side yard—even those within urban areas—is part of an intricate ecosystem that could support a great number of species is the first step toward encouraging rich, natural diversity. When “real” or “naturescaped” yards link directly to others like them, they help mitigate some of the effects of fragmentation, a huge threat to biodiversity. In general, urban and suburban areas are highly fragmented. Wildlife corridors are essential, especially for animals with large ranges.
You might be wondering, “Aren’t large-scale habitat connectivity projects happening?” or “Isn’t my yard too small to help much?” Yes, and no: The big projects are vital and projects such as underpasses and overpasses that help wildlife cross busy roads (that kill or injure many millions of animals each year) are multiplying, thanks to recent legislation in some states, as well as the federal Wildlife Crossings Pilot Program that provides funding. But also crucial are all the little spaces that—even if they’re not in the path of pronghorn or monarch butterflies—when added up, create interconnected networks. As I wrote in my book, “To be most beneficial, gardens need to connect—to each other and to the larger world—to provide continuous passage for wildlife and allow each garden to work and blend harmoniously with others nearby. A single naturalistic garden has benefits, but when in proximity to others like it, its worth multiplies.” Studies show that “the role of corridors is crucial for enhancing biodiversity in green spaces such as domestic gardens … results clarify the effectiveness of corridors in urban landscapes and have direct implications for the ecological management of cities.”
What to do? Whether you’re an avid gardener or someone who cares about dwindling wildlife, you can take positive action to help your property, balcony, or communal green spaces act as safe stepping stones within a green corridor that supports wildlife. It’s something that we can do despite (or perhaps because of) the heinous weakening of environmental protections by certain politicians over the past few years. And, it’s effective, rewarding, and usually fairly easy if you plan ahead.
Some basic tips:
Grow a diversity of locally native plants, and be sure to remove exotic invasive plants as much as possible beforehand (incrementally if they are used by wildlife). Your yard doesn’t have to be exclusively native, but when planted appropriately, the trees and shrubs that evolved in your area are especially important for supplying food, shelter, and possibly nesting sites.
Don’t fence them out (or in). When we moved into our house, one of the first things we did outdoors was remove two gates to our backyard. They served no purpose and I wanted to make it easy for four-legged fauna to come and go. While there are situations where fencing is helpful (for a dog run, to protect a veggie garden, or to prevent a little one from wandering off), many urban and suburban back yards are separated by tall, unattractive fencing that does nothing useful except provide some privacy.
Instead of impassible fencing (that also greatly diminishes air circulation around plants and, in the case of wooden fencing, wastes trees), think living, breathing native shrubs—either in an unpruned hedgerow or more naturalistic plantings—to provide privacy. Besides being much more aesthetically pleasing, shrubs alone provide food and shelter for wildlife, shade and carbon sequestration, and contribute greatly to green corridors. Unlike fencing, shrubs provide privacy but allow small animals to pass under, through, or along, from garden to garden. If your yard is tiny and you must add a narrow barrier, consider wooden lattice fencing with large openings, upon which (noninvasive) vines could grow (but don’t do this if you live where megafauna could get caught in it).
Some types of fencing can brutally kill or ensnare wildlife (and even people), often at nighttime. Avoid metal rail fencing, any spiked fencing, and all plastic netting. When not in use, take down volleyball and soccer netting.
Rethink manicured yards. Highly pruned, overly tidy, leafless, lawn-centric yards sustain very little life and are high-maintenance. Instead, create a chemical-free native wildlife garden that is more relaxed (some might say “messy”) and has the ability to support much more life. If you’re worried about what the neighbors will say, add some signs of human intention in the front: (a) Create interesting structure by varying the heights of plants so there is a connection from tall trees to ground cover—this not only looks nice, it’s great for wildlife; (b) Choose shrubs that can grow to their full potential without crowding each other out, hiding your doors or windows, or encroaching into pathways—all of which will eventually require harsh pruning; (c) Instead of one plant here, one plant there, plan for a rhythm by growing perennials in drifts or uneven clusters, and then repeat them elsewhere in your yard (this is also highly beneficial to wildlife like pollinators who need multiple plants to feed on); (d) Consider adding step stone paths, bird baths, strategically placed half-buried rocks, sculpture, or nest boxes (if appropriate), but don’t overdo it—few “focal points” are better than many. Don’t add landscape lighting, which is deleterious to living things.
Avoid “ecological traps” and minimize danger. When we grow native plants, minimize lighting, leave the leaves, add a water source and other positive elements to our yards, one of the wonderful outcomes is the increase in wild visitors. But no matter how well-meaning our actions are, “ecological traps” may be created when we make our yards welcoming to wildlife but don’t address the human-induced hazards that lurk nearby. When we design for biodiversity we must consider not just adding habitat, but also what we might inadvertently set them up for, such as being preyed upon by cats or dogs, or injured or killed by windows or some other hazard in our yard. Of course we don’t want to eliminate windows or companion animals, so we have to embrace adaptations that allow us to keep them and protect wild ones at the same time.
In other posts I’ve addressed the disastrous effect that reflective windows have on birds as well as the consequences of light pollution. Another lethal issue is free-roaming cats. Certainly not all cats are avid hunters, but many are, and it’s up to us to take responsibility for their actions. If you already have a kitty who’s been spending a lot of time outdoors, it’s going to be difficult—or even cruel—to suddenly lock him up and throw away the key. Cats are obligate carnivores, so it’s not their fault that they hunt, or want to. For those with unbreakable habits, consider limiting outdoor adventures during baby bird season (late spring to mid-summer) and at those times of the day when birds are actively feeding (typically early morning and late afternoon), and use hanging birdbaths instead of grounded ones. The next time you adopt a new cat, keep them safely indoors but offer a place to get fresh air, like a catio. Dogs, of course, may also be problematic, especially in areas where sensitive wildlife live or nest on the ground, such as fragile amphibians and reptiles.
Minimize hardscape. Unnatural hardscape does nothing for wildlife. Every time we remove hardscape and replace it with, say, regional native plants, dead wood, a water source and other beneficial elements, we help wildlife thrive. Minimizing it in your yard also helps reduce stormwater pollution, improve water quality, and mitigate the impacts of climate chaos.
Urge urban planners and park space advocates to plant native species. Despite native plants’ benefit to ecosystems and humans, they aren’t often added. A typical city park, for example, contains large expanses of lawn and some isolated trees (often non-native). Ecosystems are much more complex and may include tall trees, smaller trees, large and small shrubs, perennials and grasses, dead wood and fallen leaves, which support a large number of species. Creating native beds surrounding single trees, or at least within designated areas, will add complex layers without eliminating picnic space.
Finally, talk with your neighbors. Imagine if everyone’s yard was connected—botanically speaking—to the one next door, preferably without fences and gates. Then imagine that these connections continue from neighborhood to neighborhood and go on for miles, finally reaching a large natural area that’s even more supportive. Some neighbors may find your ideology beyond their grasp, but others may surprise you. Some people simply may not know about the deadly hazards of development and exotic plants, and speaking with them—or at least setting an example—may help to open their eyes and hearts.