This article by naturalist Mary Sonis appeared in the Chapel Hill News on November 23, 2015.
Bolin Creek saw a great turnout of migrating warblers this fall along with a solid showing of many resident species. As the birds move south to their wintering grounds, the creek offers an invitation that is irresistible to wildlife, and especially to our warblers – water.
Every day from 4 to 6 p.m., I headed out with a camera and chair, and set up my viewing station along the creek. The sound of water flowing over rocks produces of soft murmur that can be heard by any passerby. It is this sound that draws the birds. From the safely of the dense undergrowth, birds cautiously make their way down the trees and find a variety of tiny shallow rock pools. It is there that they bathe and drink at the end of the day.
Some tiny pools are so sought after that birds line up to take their turn. The diminutive Northern Parula Warbler might be driven off by a more determined (and larger) Black and White Warbler, while a migrating Chestnut-sided Warbler on its journey from the Northeast, lands without hesitation, and ignores the fray. An entire family of resident American Redstarts appears daily. Two siblings practice their flying skills by chasing each other in and out of the creek zone, often zipping by my head as if to show off their newfound acrobatic skills. The more sedate parents call the youngsters in and make their own cautious forays to a small crevice between the rocks that holds a scant half-inch of water.
What is it about this habitat that is so appealing to wildlife?
A riparian zone is the area of vegetation that borders a creek or stream. It is often a dense, impenetrable area of tangled greenery. It shades the creek, soaks up water after floods, absorbs toxins in the water, prevents erosion, and provides a protection zone for wildlife.
At creek’s edge a beaver family builds a lodge that is nestled only a few feet from the path of high school runners. It is so close a region that the beavers lift their heads when they hear a passing runner or dog walker. Box Turtles forage the moist leaf litter in search of invertebrates, and find their own soaking pools in the ruts and puddles along the main dirt path. Spotted Salamanders spend their lives buried deep beneath rotting logs in the forest and creek border, making their yearly journey to the vernal pools on the path to lay their eggs when soaking spring rains flood the trail in February.
There is only one thing that won’t fit along the Bolin Creek Trail. Pavement.
For warblers, the riparian border offers a perfect habitat. There are plenty of insects to be gleaned from the leaves, hidden sites for nests, water for drinking or bathing and finally, vegetative cover to protect the warblers from predation by the owls and hawks that patrol the creek.
A riparian border is the golden area of any creek.
It is not surprising that this creek trail also draws large numbers of humans to the Carolina North Forest. It is a beautiful trail that local residents have used for years as a peaceful spot to walk their dogs. Our outstanding Chapel Hill High School cross country running team makes their way down the path at 4 o’clock, the same time that the warblers arrive. On sunny fall afternoons, science classes from Smith Middle School can be found studying water ecology at creek’s edge. Mountain bikers join the activity as they negotiate the roots and dips along the trail.
Surprisingly, it all works. Runners, hikers, naturalists, and mountain bikers all share the beauty of this small stretch of land that winds its way from Wilson Park to Chapel Hill High School.
There is only one thing that won’t fit along the Bolin Creek Trail. Pavement. Some groups in Carrboro are advocating for a paved greenway along the creek in Carrboro. In order to meet state Department of Transportation standards, this paved path would require a buffer of 10 feet on either side. Unfortunately, that buffer would cut into the riparian zone.
This is the golden area that we can’t afford to lose. No buffer, no birds. No erosion control, no shade, no carbon absorbing trees, no Box Turtles lingering in a cool patch of muddy water on a sunny day. Is the cost too high to create yet another paved commuting route for bikers? Let the Carrboro Board of Aldermen know what this trail means to our community. Let them know if you’ve taken your children on nature walks along Bolin creek to see our Barred owls. Let them know if you want your teenagers to run that trail with dirt beneath their feet, and warblers calling in the canopy.
Mary Sonis is a naturalist, photographer and writer in Carrboro. You can reach her at firstname.lastname@example.org