Beauty in the Brambles
A Primer for Seeing Your Wild Shrub Habitat in a New Light
“It’s not just the gardeners. It’s not just the tree huggers....Each of us carries an inherent responsibility to preserve the quality of Earth’s ecosystems....The conservation of Earth’s resources, including its living biological systems, must become part of the everyday culture of us all, worldwide.”
-Doug Tallamy from ‘Nature’s Best Hope’
THE PROBLEM
In the United States, we lose roughly 150 acres of natural land every hour. That’s the equivalent of losing more than the entirety of Shenandoah National Park every year (Land Trust Alliance).
Since 1970, bird populations in the U.S. and Canada have declined by 29%, or almost 3 billion birds, signaling a widespread ecological crisis. The largest factor driving these declines is likely the widespread loss and degradation of habitat (Science, 2019).
Early successional shrub habitats are particularly important for maintaining the diversity of native plants and animals. Unfortunately, they are one of the most endangered ecosystems in the United States, often being cleared for visual appeal.
WHAT IS EARLY SUCCESSIONAL SHRUB HABITAT?
Early successional shrub habitat, also known as young forest, is a transitional habitat dominated by shrubs, a few small trees (less than 20 feet tall), vines, grasses, and wildflowers. Created by natural disturbance like fire, flooding, beavers, or storms, it is a temporary habitat that exists about a decade after a meadow gets overgrown but before mature woodland is established.
SHRUBS ARE FOR BIRDS
Seeing the beauty in the brambles.
Shrub habitats, because they receive more sun exposure than mature forests, are rich sources of wildlife forage: insects, fruits, seeds, berries, and nuts. As “nature’s pantry,” these open habitats provide year-round food and cover for mammals like deer, insects like pollinating bees and butterflies, and myriad bird species from Brown Thrashers to Eastern Towhees.
Hogwarts for Baby Birds | Shrub habitat boosts breeding bird populations even in small patches. Not only do typical shrubland dependent birds nest directly in the habitat, but even forest birds—like Ovenbirds and Wood Thrush—hone in on early successional havens after leaving their nests in the woods. Studies show that juvenile birds favor these brushy tangles over open woodlands because of the higher density of food and cover from predators during their vulnerable, formative months.
Gas Stations for Migration | Many migratory birds use early successional shrub habitats as vital stopover sites during their strenuous migratory journeys. Others, like White-throated Sparrows, take advantage of the rich accessible food sources all winter long.
Over 70% of the bird species that rely on shrub habitat are declining.
That 60% of baby birds do not make it through their first year of life?
Early successional shrub habitat is like a preschool for birds. Just as human kids must learn basic life skills in their first taste of independence, many young birds spend time in shrub habitat after leaving the nest. Without this transition, many baby birds don’t make it.
That migration is the most dangerous part of a bird’s life?
Many birds spend a third of their lives in the most perilous period: migration. Mortality rates during migration are up to 15 times higher than during any other point in their lives. Research shows that quality stopover habitat, like wild shrub habitat, can greatly increase a bird’s chances at survival.
That even some owls depend on early successional shrub habitat?
Owls like the Eastern Screech Owl need a variety of habitats for hunting, and others like the Northern Saw-whet Owl will even roost in low shrubs, hidden away from predators, while sleeping during the day.
That even common songbirds are declining wit the loss of shrub habitat in Pennsylvania?
Using special research techniques like radiotransmitting tags, ornithologists have been able to prove species’ affinity to early successional shrub habitat. You may have heard an Eastern Towhee insisting that you, “Drink your tea!!” as you walked by a dense hedgerow. This species is considered commo but steeply declining alongside the decline o shrub habitat. In Southeastern PA, Eastern Towhees may choose not to migrate during a more favorable winter. This shows the importance of shrub habitat throughout the entire year as birds choose to stay at their breeding sites.
THE SOLUTION
Embracing Messiness
Early successional shrub habitat is more varied than you may think. It’s the brushy understory of a sparse, young forest that your neighbor just cleared in the name of “cleaning up the woods”; it’s the patch of shrubs in your yard you may have considered clearing because it looks unkempt; it’s the thicket at the edge of a woodlot that your township recently brush hogged. Unfortunately, our neat and tidy aesthetic is at odds with Mother Nature’s love of “messy”.
We must recognize the critical value that threatened shrub habitats hold for birds and wildlife. Once we understand the ecological value they possess, their unconventional beauty becomes more evident. Preserving and creating this “in-between” habitat becomes second nature.
Over 80% of the land in Pennsylvania is privately owned. This means that, collectively, our own properties and yards will have the biggest impact on bird habitat conservation.
