Tracking American Woodcock



Fall 2018 Migration - Satellite Tags (Coming soon, old map displayed below.)

Cutting-Edge Satellite Research: The GoogleEarth® maps on this page show the migratory paths of American woodcock outfitted with satellite transmitters (PTTs) as part of research conducted by the USGS Arkansas Cooperative Fish and Wildlife Research Unit, USGS Minnesota Cooperative Fish and Wildlife Research Unit, and the U.S. Fish and Wildlife Service. Other cooperators providing assistance and funding are the Ruffed Grouse Society and American Woodcock Society, Texas Parks & Wildlife Department, The Glassen Foundation, Michigan Department of Natural Resources, Louisiana Department of Wildlife & Fisheries, the University of Arkansas, and Woodcock Limited.
Migration Maps: The lines on these maps show the migration paths of individual American woodcock. The colored dot represents the most recent location of that bird. The dot may not appear if no new locations have been received for several days. This happens when the solar-powered transmitter is unable to charge or successfully transmit due to weather or the thick cover used by the woodcock.
Clicking on the dots or on a point along the migration path will display the location date. Clicking the calendar icon on the right side of the map opens up a calendar. Clicking a date on the calendar will move the dots to the birds’ locations on that date.
Learning Essential Information About Woodcock: The goal of this project is to address questions on many aspects of woodcock migration such as the timing of migration, the rate and distance traveled, and what routes and stopover areas woodcock use during migration. Managers will be able to use these data to identify priority areas to focus future habitat management and conservation efforts for migratory woodcock.
Technology Used: This project uses two types of tags, a solar-powered satellite transmitter and a battery-powered combination GPS receiver and satellite transmitter. The satellite transmitter, commonly referred to as a PTT, transmits messages every two and a half days. The 48 hours on, 10 hours off cycle is used to ensure there is sufficient charge to successfully transmit multiple messages in each “on” period. A satellite passing 850 kilometers overhead receives these messages and relays them to a receiving station on Earth. The woodcock’s location is estimated by measuring the amount of Doppler shift between subsequent messages. The Doppler effect causes the wavelength of the transmission to appear shorter as the source (the PTT) and the observer (the satellite) move closer together, and longer when the source and observer move farther apart. This effect is most noticeable in the sound of a passing car horn. After processing, these locations are made available to researchers and immediately display on this website.
During fall 2015 and spring 2016 a combination GPS receiver and satellite transmitter was also used. This lightweight tag has half the mass of the solar PTT, but only functions for one migration season. The tag is battery powered and only has enough charge to collect thirty locations. The GPS tags were programmed to triangulate the woodcock’s position every three days using messages transmitted by GPS satellites. These locations are stored onboard the tag. Once the season is complete, the tag then transmits all the stored GPS locations to a satellite in one burst. This website then displays the GPS locations at the end of the migration season.
Project History: Pilot work began in fall 2013 and spring 2014, with six satellite transmitters being deployed in Minnesota (1), Louisiana (4), and Arkansas (1). An owl killed one woodcock soon after its release in Louisiana, but the other five successfully migrated. Following the migration of these woodcock, researchers continued the project deploying three additional PTTs during fall 2014 at Sherburne National Wildlife Refuge, Minnesota. Eighteen PTTs were deployed the following winter during January 2015 in Texas (7) and Louisiana (11).

In fall 2015, we began to deploy the new lightweight GPS units in addition to the solar-powered PTTs that have been in use since the beginning of the study. In all, twenty units were deployed in Michigan (11), Minnesota (4), New Jersey (2), and Wisconsin (3).
In January and February 2016, an additional twenty-eight transmitters (17 PTTs and 11 GPS units) were deployed in Louisiana (21) and Texas (7).
No additional transmitters were deployed in fall 2016. Migratory movements during fall 2016 of woodcock tagged in previous seasons are displayed above.
For more information on the specifics of the research and these maps, please contact Joe Moore, graduate assistant at the University of Arkansas. 
 Rev. 9/23/16

Spring 2017 Migration - Satellite Tags

Spring 2016 Migration - Satellite Tags

Spring 2016 Migration - GPS Tags

Fall 2015 Migration - GPS Tags

Fall 2015 Migration - Satellite Tags

Spring 2015 Migration

Fall 2014 Migration

Fall 2013 and Spring 2014 Migration


Mission Statement

Established in 1961, the Ruffed Grouse Society is North America's foremost conservation organization dedicated to preserving our sporting traditions by creating healthy forest habitat for ruffed grouse, American woodcock and other wildlife. RGS works with landowners and government agencies to develop critical habitat utilizing scientific management practices.

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