Migration

Update 5 August 2019: Spring migration came to an end around early June. A few woodcock have continued to send us locations throughout the summer, and some of these individuals have made relatively long movements after they completed their spring breeding attempts. The most interesting example is a female that seemed to nest in Michigan, and then in mid-June moved >400 miles north into central Ontario.

Spring migration was fascinating to watch, and it is incredible to think that woodcock marked throughout eastern North America have used almost every state or province throughout the species' range. We cannot wait to start capturing birds next fall and track birds for Fall 2019 and Spring 2020.

Of interest and excitement to us, a number of our woodcock marked in the southeast and mid-Atlantic this winter have initiated westerly migration routes, which is relatively uncommon in the literature. Notice the fan-shaped migration coming out of southeastern South Carolina. Another woodcock marked on the eastern shore of Maryland migrated west, across two of the great lakes and is currently in Wisconsin. All locations on the map below were collected during spring migration of 2019. Scroll further down for additional maps from Fall 2018 and from our pilot field season in Fall 2017, and for some examples of interesting woodcock behavior that represent the types of data we will use to address our project research objectives..

This map depicts migration paths of our GPS-tagged American Woodcock as they made their way from wintering areas northward during spring migration. The map includes data from birds marked during September and October 2018 at northern breeding areas, as well as birds marked during winter 2018/19 in southern wintering sites. These data will allow us to characterize important migration routes and stopover sites throughout eastern North America.

This map depicts the migration paths of our satellite-tagged American Woodcock during their fall migrations of 2017 and 2018, color-coded to the state or province in which they were marked. This highlights the significant variation in migration paths taken by individual woodcock captured in the same location. All data were collected during September-December in either 2017 or 2018, and the stopover locations of birds we followed during 2018 are showed below. Map created by Erin Pickett.

STOPOVER

During migration animals often stop to rest and refuel before continuing on their journey. This is referred to as stopover, and one question we seek to answer is how frequently and for what duration woodcock engage in stopover during their migration. The images below show two examples of stopovers from our data collected to date.

Example of a single stopover point in eastern Virginia used by a woodcock captured in upstate New York. The woodcock remained at the site for a day and then continued migration to North Carolina.

Example of a series of points collected during a 6-day stopover in southern Ohio by a woodcock captured in northwestern Pennsylvania. This woodcock continued migration to northern Tennessee following this stopover.

Migration Paths

Our satellite transmitters generally give us daily information on each woodcock during its migration, which allows us to reconstruct migratory paths for each bird. This will allow us to evaluate whether birds from different regions of eastern North America follow similar migration strategies, or if there is variation. The image below gives an example of migration paths from two birds marked in Canada that used different strategies for navigating their way around the Great Lakes.

Habitat Use

A major goal of our project is to understand how woodcock use habitat before, during, and after migration. So far we've found that woodcock exhibit a variety of habitat use behaviors, and below we give two examples.

This woodcock in central New York is exhibiting pretty classic habitat use prior to migration - its clearly using young brushy forest cover and a mix of age classes.

This woodcock, which was originally marked in central Maine, used a small golf course woodlot in eastern Massachusetts as habitat during an 8-day stopover.