Bird watching is more than fun, it has a vital scientific purpose
“In order to see birds, it is necessary to become part of the silence.” – Robert Lynd
“One can’t teach a cat not to catch birds.” – Albert Einstein
“The bird is gone, and in what meadow does it now sing?” – Philip K. Dick
We had arrived! Four small bags were affixed to a rope above us. Lizzie Diener, an avian field technician, removed one, and carefully opened it, retrieving a small bird. The tufted titmouse indignantly protested while being identified as to breed, fitted with a leg band, then aged according to plumage, measured, sexed, and blown on gently to check for body fat content and brood patches.
Each piece of information was carefully noted. “This bird has been laying eggs,” Lizzie said as she placed her in a small tube and set it on a small scale for weighing. This last piece of information was collected before release back into the woods. Lizzie repeated the process with a cardinal, a white-eyed vireo and an Eastern phoebe. These birds had just contributed to science.
Zoo staff members had come from the Tennessee River Gorge Trust (TRGT) North Chattanooga office on a beautiful day. “It’s hard to believe, but our research location is only five miles from downtown Chattanooga,” said Rick Huffines, TRGT Executive Director. He didn’t mention ‘as the crow flies.’ It was surely further travelling down Cash Canyon Road with pavement deteriorating to dirt with ruts. Eventually we walked to the open-air pavilion, cabins, tent platforms, restroom and oh yeah, a small generator for lighting.
“Are you ready to run the mist nets?” asked Lizzie. “We do it every 40 minutes,” she told us. Off we went down the hill to check for birds caught in the hard-to-see nets of thin black thread strung among the trees at various levels. No luck this visit, but walking in the woods with a view of the Tennessee River was rejuvenating.
In addition to general bird monitoring, research is being conducted with the Louisiana waterthrush and worm-eating warbler, both species of concern with declining populations in Tennessee. Holland Youngman researches the worm-eating warblers for her UTC Masters Degree. This migrant warbler needs steep slopes in mature deciduous forests and dense undergrowth. Caterpillars are the pièce de résistance.
The Louisiana waterthrush isn’t a thrush. It’s a warbler. This bird of forest streams is large as warblers go. The Louisiana waterthrush needs large forests and very clean water. They suffer from macroinvertebrates decline, four-wheel siltation, and algae blooms. It pokes along gravelly water edges bobbing its tail while looking for macroinvertebrates. After wintering in Mexico or Central or South America, it returns in spring.
This spring, Lizzie and her husband John worked with waterthrushes to pilot test a new geolocator—a device that allows bird travels to be tracked—harness design. Sixteen thrushes were caught and harnessed. Next spring, the Dieners hope to retrieve harnesses with the geolocators that will tell where the birds have travelled. Data collected will be sent to the USGS Bird Banding Laboratory to build a life cycle dataset
Why is this research important? Remember the canary in the coal mine? When the canary died, coal miners knew it was time to get out as oxygen was disappearing. Birds are an indicator species signaling human and planet health. North American Bird Conservation Initiative says 37 percent of 1,154 migratory bird species in North America are at risk of extinction. Breeding bird populations in eastern forests are declining with urban development and forest fragmentation. Picky birds are literally losing ground.
Avian research helps us know what actions to take. Much of Tennessee's forestland is privately owned. Owners greatly benefit birds by keeping large blocks of forest managed sustainably. In addition to habitat loss, the biggest reason for decline is cats followed by windows, automobiles, power lines, communication towers, and pesticide spraying. (In comparison few bird deaths come from wind turbines.)
What can you do? Keep your cats indoors. Enjoy a cup of bird-friendly coffee. Enter bird sightings in a citizen-science program such as eBird. Buy duck stamps. Support bird research.
Sandra Kurtz is an environmental community activist and is presently working through the Urban Century Institute. You can visit her website to learn more at enviroedu.net
Tufted Timouse photo by Basar