Researchers studying and working to understand the migration habits and tendencies of one remarkable bird.
One late afternoon last October, Alex Fish and I headed to a woodlot owned by the University of Maine, just a short drive from campus. The property is a few hundred acres, and was clearcut before being donated to the University. Now the forest holds a nice mix of aspen and other hardwoods with some scattered conifers and can be quite productive as a ruffed grouse cover. But with alder lowlands and a long stretch of river bottom that provide plenty of moist soils, this property is also a great cover for woodcock. This evening we were after woodcock.
Although it’s a cover I regularly hunt, our goal tonight was to catch birds for research. The property is relatively long and narrow with a single gated access road, which widens in a few places where logs were staged during the last harvest. We knew from experience that woodcock would often fly into these old log landings to roost at night. We set a series of mist nets in one of the old landings, and settled in to wait for dusk when woodcock would make their evening flights.
Studying the Woodcock Migration
Since 2017, Alex, myself, and Dr. Amber Roth, also a faculty member at the University of Maine, have been coordinating the Eastern Woodcock Migration Research Cooperative. We work with cooperating state and federal agencies, other university partners, and conservation organizations like the Ruffed Grouse Society and American Woodcock Society, to better understand woodcock migration. This is all made possible because of improved technology for GPS-tracking woodcock, which allows us to fill some serious knowledge gaps. Alex will be completing his Ph.D. in Wildlife Ecology using the data we collect.
This work is all made possible by new advances in GPS technology. We use transmitters that are in many ways similar to a GPS tracking collar on a bird dog. But to fit a small bird like a woodcock, the transmitters we use are miniaturized—about the size and weight of a grape—and instead of sending locations to a handheld GPS, data from our transmitters are relayed to us by a network of orbiting satellites and the internet. This is a major advancement in our ability to study woodcock migration because we don’t need to rely on finding the bird again to learn from it.
On this particular night, luck brought one woodcock to our hands. Her weight, the length of her bill, and the width of her outermost wing feathers told us she was a female. The patterning and shape of her inner wing feathers told us she was at least one year old, i.e.,an adult bird. I handled the bird as Alex carefully fit the GPS transmitter to her rump using an elastic harness that fit snuggly around the bird’s legs. Our banding permit, issued by the US Fish and Wildlife Service, dictates that tags can weigh no more than 4 percent of a bird’s body mass. With this girl weighing in at 205 grams, the 6.3-gram transmitter fell well below that benchmark.
The bird’s transmitter would record one location each day until the end of the year, allowing us to watch and learn about her south-bound migration from the comfort of our office at the University, regardless of how far she ventured from Maine. We’d know with a great deal of accuracy when she left on each leg of her migration and how many days she stopped in between flights. Thanks to the high precision of the GPS tag and satellite imagery available on Google Earth, we’d also know with a great deal of precision what type of habitat she used along the way. This level of detailed information has only become possible in the last decade.
Monitoring the Woodcock Migration
The woodcock remained on the University property for less than two weeks before heading south. She left sometime during the night of October 23rd, and weather records from nearby Bangor show that night was the first in weeks with a northerly wind. Cloudy skies and light rain may have given her an extra level of cover during her nocturnal flight. She flew a relatively short distance that first night, travelling just over 75 miles to spend the day near Wiscasset, Maine. The next night she continued on, flying another 140 miles and stopping just east of Boston. There, she set up shop in a small woodlot in between two fairways on a golf course. After nine days of rest, she continued onward, travelling another 90 miles to central Connecticut where she spent another 11 days resting before making a nearly 300-mile jump that took her to inside the Beltway of Washington D. C., where she spent six days on the forest edge surrounding a community center.
From D.C., our woodcock continued on nearly 100 miles into northern Virginia where she spent a single day, then another 210 miles to western North Carolina where she rested for two days, and a last leg of just over 100 miles to western South Carolina, where she appeared to settle in to an area of active forestry. The last signal we received from her was on December 13th. This woodcock migrated a total distance of just over 1000 miles during a period of 47 days.
I chose the story of this particular bird because I couldn’t help but feel connected to her. She had made her home just a few miles from my own, after all, in a cover I hunt, owned by my employer. But even though the feat of animal migration is always remarkable, in terms of woodcock migration this particular bird was fairly average. During the first two years of our project we’ve put GPS transmitters on more than 130 woodcock, and we’ve collected migration data from 113 of them. During fall migration the average woodcock travels 870 miles between its breeding and wintering areas. The average distance they fly in a single night of migration is 160 miles, and they take between 25-30 days to do it, typically stopping 4 or 5 times along the way. We know that spring migration tends to be a bit more prolonged, but with distances in about the same ballpark.
So far our total distance record goes to a male woodcock from eastern Maine who migrated more than 1,500 miles to winter in southern Alabama. Our efficiency award also goes to a woodcock from Maine that migrated more than 1,100 miles to North Carolina in just six days. The farthest a bird has traveled in a single night was just shy of 500 miles (498 miles, to be exact).
Learning from the Woodcock Migration
We often see migrant birds using a variety of different habitats, including the more traditional forested woodcock covers. But they also stop with regularity in areas you might not expect such as urban areas (including downtown Manhattan), a surprising number of golf courses, interstate highway medians, corn fields, and back yards.
As I write this, Alex is in western New York working with our collaborators from the NY DEC to capture more birds, which we will combine with a sample from four other states and three Canadian provinces to follow the fall migration of 2019. This winter, we’ll be working with cooperators across the mid-Atlantic and southeastern U.S. to capture more birds on their wintering grounds and follow them north during spring migration in 2020.
You can learn more about the project by visiting www.woodcockmigration.org. There you can also find a list of our project cooperators, learn more about the GPS technology, and download technical reports from our first two years of research. We will begin posting regular updates on the status of fall migration around October 15th.
The Ruffed Grouse Society and American Woodcock Society, thanks to the generosity of it’s members and donors, have been proudly and financially supporting the Eastern Woodcock Migration Research Cooperative. During the spring of 2019 a special fundraising campaign was held which successfully procured funds for additional transmitters to be placed on migrating woodcock. Donors received a custom American Woodcock Society vest and one lucky donor (Peter Hubbell) received a Fausti Caledon 20 GA O/U Shotgun which was also generously donated by RGS | AWS Member Steven Wilson.