To celebrate Earth Day on the
heels of the newly published 3,675-page UN ICC Intergovernmental Panel on
Climate Change 2022, we present an impassioned essay by Doug Tallamy, the
T. A. Baker professor of agriculture in the department of entomology and
wildlife ecology at the University of Delaware, who has authored 106 research
publications and taught insect-related courses for 41 years. His books include Bringing
Nature Home Press in 2007, The Living Landscape, with Rick Darke, in
2014, New York Times bestseller Nature's Best Hope, in 2020, and The
Nature of Oaks in 2021, the same year he cofounded Homegrown National Park
with Michelle Alfandari. Tallamy has been awarded recognition by The Garden
Writer’s Association, Audubon, The National Wildlife Federation, The Garden
Club of America and The American Horticultural Association.
Recently, the World Wildlife Fund
(WWF) reported that since 1970, Planet Earth has lost two-thirds of its
wildlife. This jaw-dropping news joins a litany of other recent reports about
our steady march toward the sixth great extinction event on our home, Planet
Earth: from the global decline of insects to the loss of 3 billion North
American birds in the last 50 years to the failure of the 150-nation global
biodiversity initiative to meet any of its 10-year goals, and finally to the
United Nations prediction that 1 million species will go extinct in the next 20
years. You could hardly be blamed for concluding that the demise of our fellow Earthlings
is inevitable. But to that I exclaim, “Not in my yard!”
Mention “wildlife”, and most
people conjure up images of charismatic megafauna like lions and tigers and
bears (oh my!); camels, rhinos and eagles; wolverines, jaguars, and Burmese
pythons. Yet wildlife is far more than the few large mammal species that
adorned our childhood picture books. The vast majority of Earth’s animal
species are insects and other invertebrates, as well as the insectivores, like
birds, salamanders, foxes, possums, racoons, rodents, spiders and lizards that
eat them, and we humans will not survive long on this planet without these tiny
creatures. As the late E.O. Wilson famously explained long ago: insects are the
little things that run the world. Without insect pollinators, 80 percent
of all plants, and 90 percent of all flowering plants, would
disappear, as would the food webs that support mammals, reptiles, amphibians,
birds and freshwater fishes. What’s more, the Earth would rot, as bacteria and
fungi replace insect decomposers that rapidly recycle nutrients. Wilson’s
message was clear: there will be no lions, tigers or bears; birds, bats,
bunnies or other animals or even humans in a world without insects.
Despite Wilson’s warnings, we
have waged war on many insects and ignored the basic needs of the rest for so
long that now most insects are in trouble. By one measure, the little things
that support our world have declined globally by 45 percent! Insects are not the only
important forms of wildlife, but nearly all of the more charismatic species
depend on them. The simple truth is, we cannot reverse wildlife losses without
reversing insect declines.
For the past four years I have been
photographing the moth species that live on our property (I haven’t gotten to
the butterflies yet). This year, I reached 1,140 species. That’s right: at
least 1,140 (and counting) moth species make their living on our 10-acre patch
of southeastern Pennsylvania. That is 44 percent
of all of the moth species that have been recorded in the 2.4 million acres
that comprise Pennsylvania; 44 percent
on just 1/240,000th of the land area! And because many of those moths and the
caterpillars they developed from are essential bird food, 60 species of birds
have been able to breed on our property: a full 38 percent of all the
terrestrial birds that breed in Pennsylvania. And who knows how many additional
bird species have used our land as a refueling site during fall and spring
migration?
Our property is not a preserve
that has been protected for a century. Just the opposite. Not long ago, it was
part of a small farm whose successive owners had worked the land hard for 300
years. Before we moved in, the vegetation was a tangle of invasive Asian plants
that the owners had mowed and called ‘hay’. Very few trees and native shrubs
grew here, and most of the resident birds were introduced starlings and house
sparrows that could thrive on exhausted farmland. The caterpillars that sustain
96 percent of North
American terrestrial bird species were largely absent.
But today, rather than having
lost two-thirds of its wildlife as WWF suggests, our 10 acres has increased the
number of its resident species by at least that much. And it did not take
decades for those increases to occur. The depleted agricultural wasteland of
two decades ago has become a hotspot for local wildlife. How did this happen?
The seemingly astounding rebound
in species on our property was actually neither astounding nor accidental. It
was a predictable response by the natural world to our purposeful restoration
of nature’s foundation: native plants. The moths I am counting have returned
because the native plants they require are now here, as well. And those plants
are thriving on our property because along with the wind and the local blue
jays, we have planted them. We also have removed the tangle of Asian invasive
species so that our native plants have enough space, light and water to grow.
The birds and other vertebrates
that live on our land can do so not just because of the moths our plants
produce, but also because of the fruits and nuts our oaks, black walnuts,
hickories, filberts, blackberries, serviceberries, dogwoods, persimmons, black
cherries, pawpaws, chokeberries, viburnums and black gums make each year.
Winter birds like juncos and white-throated sparrows migrate to our yard
because of the copious amounts of seeds produced by our native grasses,
sweetgums, sycamores, evening primroses, asters, wild lettuce, black-eyed
Susans, and goldenrods. Red-shouldered hawks, Cooper’s hawks, and sharp-shinned
hawks regularly hunt here because their prey is so abundant. And it is hard to
walk anywhere in the spring and summer without encountering the cutest little
gray tree frogs imaginable.
We have planted native plants
because 90 percent
of the caterpillar species that transfer more of the sun’s energy from plants
to other animals than any other plant-eaters are unable to develop on
non-native plants—those Asian ornamentals we habitually decorate our yards
with. Most insects can only use plants after they have evolved adaptations that
counter the chemical and physical defenses of those plants. Such adaptations
take eons to appear, eliminating the chance that decorative plants from other
continents can serve as viable host plants for most of our insects. Those
plants simply have not been here nearly long enough for North American insects
to adapt to them, even though many have been here hundreds of years. When we
allow non-native plants to replace native plant communities, either as
well-behaved ornamentals or invasive species that ecologically castrate local
ecosystems, caterpillar populations decline by up to 96 percent.
Will our 10-acre restoration
alone be able to reverse global declines in wildlife? Of course not, but if
ecologically appropriate plant choices were consistently made by homeowners,
land managers and municipalities everywhere, the habitat value of all
non-agricultural land would be measurably enhanced, just as it has been on our
property in Pennsylvania. Most ag lands can be improved as well by liberal use
of pollinator strips and hedgerows rich in native plant species. Aided by
groups like the National Wildlife Federation, National Audubon, Wild Ones, Grow
Native, the Wild Seed project, the Missouri Prairie Foundation and the
California and Florida Native Plant Societies, such transformations are well
underway across the country, and just as on our property, the results are
beginning to defy global wildlife trends.
Returning native plants to our
landscapes provides essential energy for species-rich food webs on any scale,
be it 10-acre parcels like ours in Pennsylvania, half-acre suburban lots like
Margy and Dan Terpstra’s, near St Louis (
Tinyurl.com/HummerHaven), one-tenth-acre
city lots like Pam Karlson’s, in Chicago (
Tinyurl.com/Bio-FriendlyGardens), or
even the three-foot-wide strip of nature along Manhattan’s High Line (
Tinyurl.com/WildBeesOnHighLine).
The loss of biodiversity is a
global crisis, but it is a crisis with a grassroots solution. Somewhere along
the line, we assigned Earth stewardship to just a few specialists: a handful of
ecologists and conservation biologists. The rest of us have had cultural
permission to destroy the natural world whenever and wherever we wanted, using
oxymoronic words like ‘development’ and ‘progress’ as rationalizations. The
United Nations has designated Biosphere Reserves as places of ecological
significance, but that language suggests that there are places on Planet Earth
with no ecological significance. Not so! Every square inch of the planet has
ecological significance, including our yards.
The ecological approach to
landscaping that I have described here is nothing more than basic Earth
stewardship, but it is stewardship that empowers us all to become forces in
conservation. Replace part of your lawn with ecologically powerful native
plants; remove those ornamentals that have proven to be invasive; and plant a
pollinator garden. Even if you don’t own land, you can make a difference by
volunteering to help your local land conservancy manage its properties or
simply by helping someone who does own property. Either as property owners or
volunteers, each of us has the power—and we clearly have the responsibility—to
enhance the ecological value of local landscapes. My yard’s message is loud and
clear: most wildlife losses are reversable! Humans can coexist with the natural
world, at the same time, in the same place. Whether we decide to do so will
determine nature’s fate and ultimately, our own. In that sense, we all are
nature’s best hope!
