- May 29, 2018
As you explore wildlife landscaping recommendations, you will find a common theme around mowing. Conservationists are always encouraging people to mow their lawns less often or not to mow their fields from May to August. What is that all about?
To sum it up: RESOURCES FOR WILDLIFE. Our lawns provide important nectar and pollen for pollinators which is lost or minimized when we mow. Fields (grasslands and meadows) also act as important food and breeding locations for numerous wildlife. Keep reading to learn more about the species you can protect by modifying your mowing practices.
Delayed mowing allows for grasses and forbs to mature and flower, providing much needed pollen, nectar, and seed resources to native bees, butterflies, and birds. Additionally, the mature plants provide the habitat needed for nesting, egg laying, and shelter.
In the early spring, “weeds” like the common dandelion (Taraxacum officinale) and white clover (Trifolium repens) start to grow and bloom. This is a valuable nectar source for early active pollinators. Mowing your lawn less often, allows these so called weeds to bloom and provide important resources to bees and butterflies that need them early and throughout the season. In fact, research has shown that these two weed species can provide resources for over 50 species of pollinators including bumble bees (Bombus spp.), butterflies (Lepidoptera spp.), hoverflies (Syrphidae spp.), and honey bees (Apis mellifera) to name a fewopen_in_new.
The monarch (Danaus plexippus), a specialist, is an example of a species that benefits from conservation mowing practices. Milkweed (Asclepias) populations have decreased over the years due to agricultural management and development. Milkweed, as hinted at by its name, is considered a weed, in part, because it can be poisonous to livestock. Mowing and removal are traditional in agricultural practice, which in turn, reduces the ability for monarchs to reproduce and complete their life cycle. Allowing milkweed plants to mature, produces food for both the monarch larva and adult butterfly.
North America has over 450 breeding bird species.open_in_new Of those, grassland birds have experienced the largest declines in populations over the last 40 years.open_in_new Their population declines are linked with habitat disturbance‒including mowing regimes. Pictured above is a Field Sparrow (Spizella pusilla) nest found in a working farm field in Virginia. Field Sparrows have lost nearly half their population since 1970 and are expected to lose up to half of their current population in less than 40 years. Modifying harvest, mowing, or grazing schedules can increase nest success and can help Field Sparrows, and many other species, recover.
Mowing earlier in the spring (before May) or later in the summer (August), not only increases nesting success, but also gives fledgling birds one less obstacle to face as they navigate life outside the nest. Think of fledglings like teenagers, they are able to leave the home on their own but are still under the close watch of their parents–not yet having all the skills (or flight feathers) needed to make it on their own. The fledgling stage is different in every bird species, but typically fledglings hang around after leaving the nest.open_in_new Delaying mowing practices will help these birds make it to adulthood.
Consider searching for nests before starting any management practices during the breeding season. Most grassland birds build their nests on the ground or within a couple inches of the ground.open_in_new Breeding birds are more likely to flush from a nest in the morning and early in the breeding season‒while still on eggs‒therefore making nests easier to find.
The top conservation action to help these species is to maintain grasslands with mowing techniques that support nesting and fledging survival.
Once the eggs have hatched, most adult birds‒like the Common Yellowthroat (Geothlypis trichas) pictured above‒fool predators.open_in_new To hide their nest location, some birds walk into and out of the nest with food, so that where they disappear or reappear from the vegetation is not the location of the nest. Most nests will look like grass clumps and/or large accumulation of dead plant material. Below are some examples of bird species that nest in grasslands and need our help.
Eastern (<em, pictured above) and Western Meadowlark (Sturnella neglecta) populations have declined 89%open_in_new and 48%open_in_new respectively since 1966. With over 73% of these two species habitat in private ownership, habitat loss and poor land management, like mowing or harvesting during breeding season, contribute to population declines.
The backward wearing tuxedo bird, also known as the Bobolink (Dolichonyx oryzivorus) has seen a 67% decline in populations over the past 50 years and they are listed on the 2016 State of North America’s Birds’ Watch List‒which lists birds that are in the greatest risk of extinction.open_in_new The top conservation action to help this species is to maintain grasslands with mowing techniques that support nesting and fledging survival.
Once a common game species, the Northern Bobwhite (Colinus virginianus) has experienced a steep decline in populations (85%) in the past 50 years. Much of this decline is due to habitat degradation and conversion. While mowing and grazing help to maintain the grasslands Bobwhites rely on, when conducted during nesting season they often destroy their ground nests. The population decline of the Northern Bobwhite also incurs an economic cost. Once a highly-prized game species, now populations are so low, hunting, and the money associated with licenses and equipment, are no longer available to communities that depended on that influx of cash.
White-tailed Deer (Odocoileus virginianus) are common throughout most of North America because of their ability to inhabitat many different types of habitats.open_in_new Grasslands and working fields provide important nutritional resources and cover for fawns and mothers at this vulnerable time in their life. Fawns are able to walk within hours of birth; but, for the first couple weeks after birth, the mother will hide the baby while she forages alone.open_in_new The fawn is programmed to lay still and freeze while waiting for its mother to return. If danger arises, including danger from a mower/ tractor, the fawn will often not move, making it vulnerable to injury.
The Cottontail Rabbit Genus (Sylvilagus) is made up of around 20 species of cottontail rabbits, with the Eastern Cottontail Rabbit (Sylvilagus floridanis) being the most widely distributed species in the Americas. Pictured above, is an example of the shallow ground nest of the Eastern Cottontail Rabbit that looks like a brown patch of grass/lawn. These nests can be extremely hard to identify because, let’s face it, most of our lawns can look this way at times. The nest pictured above was observed that “the ground was moving” therefore professional were called. But as the saying goes, breeding like rabbits, cottontails are known to breed three to four times a year and babies mature to reproductive age after two to three months. Their nests can easily be disturbed or destroyed if you do not know what to look for.
Frogs and toads have great camouflage and are known to sit and wait, or flee at the last moment. They are great yard guests to have, as they help manage pests such as mosquitos, slugs, flies, etc.. However, these animals are often caught in the crosshairs of mowers along their journey of resource acquisition. Their survival techniques, which are designed to evade predators, make them susceptible to injury when we mow.
Another example of a common species in our yards and fields is the Eastern Box Turtle (Terrapene carolina). Much like the frogs and toads, the defensive mechanism for box turtles is to retreat into their carapass, or shell, until the danger has subsided. It is important to keep a watchful eye when mowing for this species, as they will not flee, but rather remain in the mower’s path, which can result in serious injury or death. This species is not nationally recognized as a species of concern, but many states do list it, so please keep an eye out–a yellow-orange patterned-looking rock or root‒for turtles while you mow.
One last species that is a great yard species to have is a garter snake (Thamnophis)‒also known as the gardener snake or ribbon snake. I know many of you just shuddered at the fact of a snake in your yard, but garter snakes, and really all snakes, are another pest-controlling animal. They feed on many animals we don’t want in our gardens and yards including mice, ants, crickets, and slugs. Like frogs and toads, they retreat, but can be trapped in our mowing patterns and left with no escape.
Whether it’s your lawn or your back 40, mowing practices are simple, dare we say, lazy management action that can benefit many important species in our landscape. Who knew by eliminating or minimizing mowing from May to August you could benefit so many species of wildlife. Be a part of the solution for protecting our valuable grassland wildlife‒mow less and enjoy your habitat visitors more!