How to Minimize ‘Ecological Traps’ Within Naturalistic Gardens

 

When we add local native plants to our yards and work to mimic healthy habitats, one of the wonderful consequences is the increase in wildlife we see. But no matter how well-meaning our actions are, “ecological traps” may be created when we make our yards attractive to wildlife but don’t address all the inherent dangers that can lead to reduced survival or reproduction. If human-induced hazards — such as reflective windows, introduced predators, light pollution, dirty bird feeders — kill or injure them, it’s obviously not advantageous. To minimize danger to wild fauna that unknowingly select attractive but inferior habitats in which to feed, shelter, or reproduce, we need to consider and address what we might set them up for when we purposely design ecologically-attractive landscapes, as well as embrace adaptations that allow us to protect wild ones at the same time.

It’s easy to figure out some ecological traps, such as those created by gardeners who use insecticides on plants that attract insects, or brutal traps or poisons intended to kill rodents that can also trap or harm other animals. But there are many other less obvious ways that gardeners may attract wildlife into gardens, only to ultimately harm their chances of successful reproduction or survival.

For birds, after habitat loss and degradation, free-roaming cats and window collisions are the greatest human-related causes of fatalities. In another post I’ve addressed the disastrous effect that reflective windows can have on birds. Regarding cats, certainly not all are keen hunters, but many are, so it’s up to us to take responsibility for their actions. (Dogs can also be problematic, especially in areas where sensitive wildlife live or nest on the ground, including fragile amphibians and reptiles.) Domestic cats reportedly kill billions of birds a year, in addition to reptiles, small mammals, insects and amphibians. So what’s a responsible animal lover to do? If you already have a feline who’s been spending a lot of time outdoors, it’s going to be difficult—or even cruel—to suddenly lock Kitty up and throw away the key. Cats are carnivorous predators, 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 to mid-morning and late afternoons, although keep in mind that while there’s usually a lull in activity at mid-day, some smaller birds and juveniles might visit feeders then). 

The next time you adopt a new cat, make them into a “house cat” early on (especially if they’re young and have never been outdoors or just had a “taste” of it for a short time) and, if feasible, offer a place for them to get fresh air and sunshine, like a catio. (I honestly do not know what we’d do without ours!) Catios can also keep them healthier, since studies reveal that feline hyperthyroidism is caused, at least party, by the dust from flame retardants in bedding and electronic devices. If a neighbor’s cat is the problem, it might be best to not use feeders at all.

Other backyard “traps” include:
> Light pollution: Outdoor lights (especially those attractive to insects, such as moths) can disrupt flight paths and lead to exhaustion or death. Please see this post for information on how to minimize insect mortality, as well as migratory bird mortality, plus other serious problems associated with unnatural and unnecessary lighting.
> Using pesticides (insecticides, herbicides, fungicides,rodenticides) that kill insects, including pollinators, or taint food for other wildlife and possibly poison them.  
> Inadequate bird nest boxes or lack of protection: Nest boxes that lack proper protection from predators or are placed in exposed locations can lead to nest failure. Choosing the correct entrance hole size for the species is sometimes all that’s needed. Also, nest boxes not cleaned annually can lead to disease—it’s helpful to disassemble the box soon after the birds have fledged and clean it well; I like to then place the pieces of wood in the hot sun for a couple of days.

> Hazards for ground-nesting birds. Some species, such as towhees, killdeer, and some sparrows and juncos, nest on the ground or close to it, so even in the best habitat it’s natural for some nests to fail due to location and predation. If you do notice such a nest and your bird feeder is attracting crows, cats, dogs, or raccoons, take it down until the birds leave the nest.

> Poor placement of bird feeders and/or bird baths that attract predators. While providing food for birds can be beneficial, always place feeders and baths in a place that allows birds an effortless flight to a nearby tall shrub or tree, where they can escape or avoid potential predators. Placing them within a few feet of windows or at least 30 away will help prevent collisions with reflective glass.  Hanging bird baths are best in areas where carnivorous animals are seen frequently. 

> Infrequent cleaning of bird feeders. 
Dirty, poorly maintained feeders can lead to the spread of disease.
> Drawing too much attention to a nest, such as a cup-nest (built by birds such as robins and warblers) in a shrub or tree. Give the birds plenty of space, avoid outdoor lighting and loud noise, and keep kids and companion animals away.

> Allowing tall grass to attract ground-nesting species and then mowing it during nesting season, which can destroy the nests and possibly nestlings. 
> Fencing that blocks wildlife corridors and, as I wrote in the Green Corridors Begin at Home post, types of fencing that 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.
> Flowering plants and other habitat near busy roads: While roadside habitat is not always harmful, (studies show that it depends on traffic intensity, the distance of plants to a roadway, the frequency of mowing and pesticide spraying, and the availability of alternative habitats nearby), “pollinator-conscious management practices can help roadsides become more of a boon and less of a bane.” Since we lack the data needed to understand the overall impact of roadside vegetation on pollinator populations, we need to be very cautious and focus on pollinator plantings grown in safer areas whenever possible.
> Non-native plants: Some non-native plants can be attractive to wildlife but may not provide adequate nutrition or shelter, leading to an ecological trap, according to the National Wildlife Federation. This also applies to cultivars (a.k.a. “nativars”), which are cultivated varieties of native species (not natural varieties found in nature) that have been cross-bred and/or hybridized by breeders looking for certain characteristics (like plant size or flower or leaf characteristics). Studies show that while some are fine, many aren’t as attractive and useful; their pollen, nectar or fruit may be deficient in nutrients (which is especially bad for migrating birds who need quality nutrients that provide a lot of energy). And some may actually lack nectar or their flowers are so complex that pollinators can’t even use them. Studies on native cultivars in the northeast and at OSU found that the more manipulated the cultivars became, the less attractive they were to pollinators. And since the interactions between insects and plants are so complex and because we don’t have an exact list of which are adequate and which aren’t, it’s safest to minimize the use of cultivars and stick with true native species.
> Leaf-blowers, for many reasons: Their powerful blasts destroy essential wildlife habitat (such as leaf cover for overwintering arthropods and amphibians), kill or injure them, stir up harmful dust and air pollutants, and remove leaves, mulch and topsoil, which can cause erosion and harm soil health. Their noise frightens animals and disrupts communication. Gas-powered blowers expel huge amounts of fine particulate matter, volatile organic compounds, and nitrogen oxides, intensifying smog and respiratory issues. 

In a proverbial nutshell, reversing biodiversity loss must involve both growing local native plants and protecting the wild ones by supplying a safe space for them … if we fail to do the latter we cannot claim to help.

 

© Eileen M. Stark 2026

Just the Thicket … For Wildlife Habitat


If you’re looking for ways to counteract — in a small but significant way — the relentless destruction of the natural world and want to turn your yard into a place that supports the wildlife community, or you already garden for biodiversity, you probably know that appropriate habitat — food, water, space, cover — is essential. Food is best supplied by regional native plants that produce insects, nectar, pollen, fruit, and/or seeds, while water comes either from natural sources or human-made birdbaths or ponds. Adequate space is important to prevent competition for food, cover, and nesting sites. Cover, or shelter, is as crucial as the others because wild fauna need places that not only shield them from inclement weather, but also hide them from predators (and people). Predatory animals themselves often need cover to successfully obtain prey. A lack of cover is a limiting factor for many wildlife populations.

Increased biodiversity comes with careful planning and placement of cover habitat supplied both vertically and horizontally with small and large native shrubs and trees. Those with particularly dense foliage may also provide valuable nesting habitat, as well as privacy for you, or even a windbreak if strategically placed.

Thickets are a great way to provide cover for relatively small animals, due to their tendency to be impenetrable to large species. They may be dense groups of trees or shrubs, usually dominated by one or a few species that tend to be multi-stemmed and often densely twiggy, or they may be formed by a single species that either enlarges via underground suckering stems or sheds large numbers of seeds that have the ability to grow beneath or close to the parent plant. Thickets of the latter type may also be spread by human disturbance. 

Even when leafless, red-twig dogwood (Cornus sericea) attracts birds.


Because thickets tend to fill quite a bit of space, they usually are not suitable for very small gardens, since they will tend to “take over” a small space, either fairly quickly or over many years, depending on the species. But if you have a fairly large yard or an acreage, native thickets create mini-ecosystems within which essential food and cover are supplied for a large number of beneficiaries, from insects and birds to reptiles, amphibians and mammals, depending on the location. They’ll also conserve soil moisture and may slow — or even prevent — erosion on slopes. And, when well established, thickets keep out many invasive weeds (note: always remove weeds well before planting any type of native plants). Many of these plants also can provide food for us, but I suggest you share with wild visitors.

Thickets often get a bad rap because they don’t look particularly neat and orderly, but if you garden for wildlife you know that messy and naturalistic is much better for the wild ones. To tidy up shrubs that tend to develop into thickets, gardeners often clip out suckers and sprouts for appearance’s sake, but that’s to the disadvantage of wild visitors.

Pollinators love thickets!

Although thickets (especially thorny ones) may not be suitable for most front yards, in back yards or other areas, they can be wonderful wildlife magnets. And when located as far from human activity as possible, they also lend tranquility in an urban environment. Though my yard is just one sixth of an acre, I have several thickets—one that’s composed of snowberry and clustered rose, several of tall Oregon grape, and a large clump of thimbleberry. It seems there’s almost always something going on: A little bird or two flitting around branches looking for food, a ground feeding bird foraging within fallen leaves, pollinators hard at work, or — during nesting season — a bird vocally establishing his territory. Flowers’ pollen and nectar attract a variety of native pollinators in springtime, fruits or seeds become available later in the year, and the rose offers a place for mourning cloak butterfly larvae to develop.

Choosing thicket species
In nature, thicket-developing plants grow in forested areas, as well as open areas such as historic savannas (a grassland with trees scattered at least 100 feet apart), upland prairies (another type of grassland) or wet prairies. Needless to say, savanna/prairie plants require more sunlight than forest thicket species. Since humans have converted most savanna and prairie habitat to agriculture and livestock grazing, those thicket species aren’t having an easy time; they’re mostly forced to live on forest edges and fence rows and are threatened by invasive species.

Prairie or savanna thickets naturally would be surrounded and complemented by native herbaceous plants and grasses that are members of a plant community, which together would create a highly supportive ecosystem. Forest species also would naturally occur with ‘associates’ that interact and flourish together.

Thorny native thickets, such as this Rosa pisocarpa, offer a place for birds to rest as well as forage.


Here are some plants that typically will form thickets in the Pacific Northwest, west of the Cascades (but it’s not an exhaustive list). Choose species that would naturally occur in your area; check native status to county level here.

For sun to part sun: Douglas hawthorn (Cragateus douglasii), Red-twig dogwood (Cornus sericea), California hazelnut (Corylus cornuta var. californica), Western crabapple (Malus fusca), Western serviceberry (Amelanchier alnifolia), Ninebark (Physocarpus capitatus), Tall Oregon grape (Mahonia aquifolium), Bitter cherry (Prunus emarginata var. mollis), willows such as Salix scouleriana, S. lucida, S. hookeriana, and S. sitchensis, red-flowering currant (Ribes sanguineum), wild roses (Rosa nutkana, R. pisocarpa), Douglas spiraea (Spiraea douglasii*), white spiraea (Spiraea betulifolia var. lucida), Thimbleberry (Rubus parviflorus*), Salmonberry (Rubus spectabilis*).

For part shade to shade: Red elderberry (Sambucus racemosa), Snowberry (Symphoricarpos albus), Osoberry (Oemleria cerasiformis), Salal (Gautheria shallon).

* may spread rapidly.

Fox sparrow foraging beneath a thicket stays safe.



© 2020 Eileen M. Stark

Damselflies: Live Fast and Die Young

northern bluet

This bright and handsome damselfly, resting on a stem of a columbine plant in my garden, is a male Northern bluet (Enallagma annexum), one of 466 species of damselflies and dragonflies found in North America. They make up the two main subdivisions of a very distinctive group of insects known as Odonata (Greek for tooth), which refers to their powerful and sharply toothed jaws, adapted for biting and chewing their prey.

Damselflies can be distinguished from dragonflies by their smaller size and their position when at rest: Damselflies typically hold their bodies horizontally, with their tear drop-shaped wings neatly and elegantly folded together over their abdomen, while dragonflies generally hold their wings flatly, outstretched and perpendicular to their body.

I’ve wondered about the common names. Since “damsel” conjures up an image of a fair maiden—most likely in distress—I imagine that the damselfly was so named because it is more delicate looking than a dragonfly and isn’t as tough and strong a flyer. Plus, proverbial dragons kept damsels in their caves, didn’t they? But now we need to ask, why are dragonflies called what they are? According to a 1958 book by Eden Emanuel entitled Folklore of the Dragonfly, it’s theorized that the common name emerged due to an ancient Romanian folktale, in which the devil turned a beautiful horse ridden by a saint into a giant flying insect. The Romanians supposedly called this giant insect (when translated into English) “St. George’s Horse” or “Devil’s Horse.” Peasants probably considered the Devil’s Horse a giant fly, and it’s surmised that they started referring to it as “Devil’s Fly.” Emanuel concluded that the Romanian name for Devil’s Fly was erroneously translated into English as Dragon Fly and this then evolved into the present-day “dragonfly.”

Gradual Metamorphosis

The female Northern bluet is generally greenish-yellow or tan, with a black abdomen. She lays her eggs in submerged vegetation; upon hatching—typically late spring to early fall—the young nymphs (or naiads) are small and wingless, but fully functional, so they don’t go through larval or pupal stages like most other insects do. Nymphs spend their time (often years) underwater in bogs, lakes, ponds, or rivers, where they molt (shed their skin) about a dozen times while growing. Fierce predators of aquatic organisms, they hide in submerged vegetation and attack the larvae of smaller insects such as mosquitoes and mayflies. When they are about an inch long, they crawl out of the water onto rocks or grasses and such. After a brief sunbath, their skin splits down the back and they struggle to pull themselves out of their shabby old skin one last time. Voila! Metamorphosis complete, they are now all grown up and it’s time to inflate their new wings and abdomen and harden fresh legs, all of which likely takes a lot of energy. Adults generally live less than two weeks, breeding and feeding—just enough time to live fast and die young.

Like dragonflies, damselflies’ large, bulging eyes have thousands of honeycomb-shaped lenses that give them an ability to see in all directions and make them formidable predators of other insects. Adults are swift aerial hunters, typically preying on mosquitoes, small moths, and various flies. Fascinating research shows that Odonata don’t dive and turn in reaction to their prey’s movements—instead, they are able to predict those movements before they happen. But what goes around comes around: Both damselfly nymphs and adults are consumed by birds, frogs, fish, and, yes, dragonflies.  Northern bluet

Conservation

Dragonflies and damselflies go way back, pre-dating dinosaurs by at least 75 million years. Fossils of ancient ancestors dating roughly 300 million years ago were gigantic—the largest insects ever to live—with wingspans of about 30 inches! Northern bluets are somewhat common damselflies, often found near freshwater—streams, rivers, and other watery places (even human-made ponds)—but their dependence on it makes them very vulnerable.

All damselflies and dragonflies are good indicators of the diversity and health of aquatic ecosystems, their presence suggesting that a body of water is fairly unpolluted. Destruction or alteration of wetland habitats, pollution, and pesticides are the greatest threats to Odonata species worldwide. Without clean water they cannot breed, and without insect life they cannot eat. Needless to say, as long as humans continue to allow alteration of their habitat through climate chaos, there will likely be a severe threat to future populations.

On pleasant, sunny days I often notice dragonflies and damselflies patrolling my organic, “real” garden. Should these brainy little hunters find their way into yours, consider yourself very fortunate!

 

© 2015 Eileen M. Stark

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