A Revolution in Migration Research
The Motus Wildlife Tracking System (motus.org) is revolutionizing the study of winged migration by revealing intimate, never-before-seen details about migration routes, timing, flight speed, stopover behavior, the locations of critical migratory and overwintering habitat, and more. In 2020, the Harris Center joined this cutting-edge, international research effort by installing a Motus receiving station on our Granite Lake Headwaters property in Stoddard.
How It Works
Motus (Latin for “motion”) is comprised of small, lightweight radio transmitters (nanotags) that are affixed to shorebirds, songbirds, small owls, bats, and even butterflies, along with a network of antennas that detect the radio signals whenever a tagged animal flies within range. Any tagged bird, bat, or insect that flies within 10 miles or so of our station in Stoddard will be recorded. This station is sustainably powered by a solar panel, and transmits data via cell phone signal. Data can typically be viewed within days at motus.org.
Species Spotlight: Wood Thrush
One of eleven Wood Thrushes tagged with nanotransmitters in the Monadnock Region in 2024. (photo © Phil Brown)
The flute-like song of the Wood Thrush is a familiar sound in Northeastern hardwood forests, but in recent years it has become less common: Wood Thrush populations in North America have declined by more than 50% since 1970. They are now considered a priority species for conservation efforts in New Hampshire and many other states. A new United States Fish and Wildlife Service (USFWS) project is using the Motus network to track the migration of Wood Thrushes to and from their wintering areas in Mexico and Central America, with the hope of providing data that can be used to protect this bellwether species.
The USFWS initiative is ambitious in scale: in 2024, biologists affixed Motus transmitters to nearly 600 Wood Thrushes at breeding sites in 24 states and Ontario, along with an additional 100 birds on their wintering grounds in Central America — the largest single-species Motus project to date.
In May 2024, in partnership with NH Audubon and Antioch University New England, the Granite State’s very first tagged Wood Thrush was banded a stone’s throw from the Motus tower on the Harris Center’s Granite Lake Headwaters property. In the following weeks, ten additional Wood Thrushes were tagged in the Monadnock Region. From now on, these birds will be logged anytime they pass within range of a Motus station on any continent, yielding vital data on their migratory routes, survival, and conservation needs. This is just the beginning: our team is gearing up to tag more Wood Thrushes in the SuperSanctuary in the spring and summer of 2025. You can help guide their efforts by reporting your Wood Thrush sightings to eBird!
What Sets Motus Apart?
For more than 100 years, scientists have been using bird banding – in which individual birds are captured, fitted with a metal band containing a unique number, and released back into the wild – to learn more about our feathered neighbors. Banding has provided vital insight into avian ecology, but it has one significant limitation: in most instances, banded birds need to be recaptured in order to yield this information, and the chances of re-sighting a banded bird are incredibly low.
In the last few decades, GPS and satellite transmitters — such as the ones used in our Broad-winged Hawk tracking project with Hawk Mountain — have led to more detailed data on bird movements and, in many cases, allowed biologists to retrieve data without recapturing individual birds. However, these technologies can only be used with larger species, which can support the added weight of the transmitters. By contrast, Motus nanotags can be safely attached to a diversity of smaller species, including songbirds, bats, and dragonflies. To date, more than 400 species worldwide have been tagged through the Motus network.
A map of existing and proposed Motus receiving stations in New England, including four new east-west “fencelines” designed to detect tagged birds as they fly north-south. Click on the map to open a larger, interactive view. (map © Motus New England)
New England Motus
Initial Motus efforts focused largely on the Atlantic, Gulf, and Great Lakes coastlines, but the New England Motus project aims to establish a series of 50 receiving stations in east-west “fencelines” that will detect tagged wildlife as they migrate north-south through interior Connecticut, Maine, Massachusetts, Rhode Island, Vermont, and New Hampshire. The Granite Lake Headwaters station was the first of these 50!
Project Partners
Partners on the New England project include NH Fish and Game, NH Audubon, Mass Audubon, Maine Audubon, the Maine Department of Inland Fisheries and Wildlife, the Massachusetts Division of Fisheries & Wildlife, the Carnegie Museum of Natural History, and the Willistown Conservation Trust.
Contact Us
For more information on the Harris Center’s Motus station, please contact Brett Amy Thelen by email.
