Purple Martins

Conserving Purple Martins and Studying Natal Dispersal

The Lehigh Valley Audubon Society, The Acopian Center for Ornithology at Muhlenberg College, and Northampton County Parks and Recreation have worked hard to bring Purple Martins back to the Lehigh Valley over the past few years in places like Lake Minsi. With these colonies now boasting large numbers of breeding martins, the question arises: where will the newly hatched Purple Martin chicks nest? Some will return to the colony where they were born, if there are empty nesting gourds. Many of these birds, once they return to the Lehigh Valley for their first breeding season, will have to find somewhere else to nest. Where will these martins go?

Photo of Purple Martin Tower Information Sign

This phenomenon is called natal dispersal. It is the permanent relocation of a Purple Martin during the breeding season, and it is an important part of how the birds find new nesting colonies. Natal dispersal remains a mystery for martin enthusiasts and researchers alike, and we’re trying to answer this question.

In conjunction with the University of Delaware and the Purple Martin Conservation Association, we are studying how far and frequently Purple Martins disperse from their breeding site. This information will be critical in the establishment of new colonies.

Purple Martin chicks are being color banded in the Lehigh Valley to track this natal dispersal. Each martin chick gets a color band that ties it to the colony where it hatched. Then, we can “resight” this bird in the field the next year, and see how far the bird has dispersed, based on where that bird is re-found. More banding from our collaborators is starting in southeastern and northwestern Pennsylvania. All of the martins across the state are color banded with a unique combination of colors, so we’ll know exactly where each banded bird we find originated.

Because Purple Martins can disperse so widely, we need your help looking for dispersed birds! Whether you have Purple Martins nesting on your property or in a local park, you can participate in this research project by looking for small, colored bands on the legs of Purple Martins. If you see a color banded bird at your colony, please let us know! First, record what color band or bands you see, the relative position of each band, and which leg the bands were on. If you have a camera, take some pictures! The easiest way to submit your sightings is with this web form: https://bit.ly/PA_Martin_Study. If you have pictures of a color banded bird at your colony, you can send them to Will Krohn, the graduate student at the University of Delaware helping conduct this research, at wkrohn@udel.edu. If you can’t complete the online form, you can also call Will at 484-702-1276.

Read more about recent LVAS Purple Martin towers.

Support our conservation efforts in the Lehigh Valley by becoming a member of our chapter, volunteering with us &/or donating.

Engage with LVAS, Help Maintain and Monitor Purple Martin Condos

We’ll need more help this year with installation labor, monitoring, maintenance, winter storage, and, of course, all the banding and data collection done each nesting season.

There were NO Purple Martins nesting at Minsi Lake before 2020. Thanks to Lehigh Valley Audubon Society (LVAS) volunteers, a large and growing Purple Martin colony can now be seen at Minsi Lake.

In 2024, the Northampton County Parks and Recreation and LVAS partnership managed 108 condos in six nesting towers—five at Minsi Lake Park and one at Louise Moore Park. Occupancy during nesting season in the Minsi Lake condos was over 90% with nesting pairs in 80 of the 90 condo units, including 36 new units.

Interested in volunteering? Email James Wilson, Recreation & Conservation Specialist for Northampton County Parks, at jwilson@norcop.gov to help with this Purple Martin project.

Complete the LVAS Volunteering Form to let us know what other volunteer opportunities might interest you.

Read more about Purple Martins at Minsi Lake.

Purple Martins at Minsi Lake

Jim Wilson, Recreation & Conservation Specialist, Northampton County Parks

Originally Published in July - September 2024 Quarterly Newsletter of The Lehigh Valley Audubon Society

There were no Purple Martins nesting at Minsi Lake before 2020.

Purple Martin project at Minsi Lake

Since Northampton County Parks Martin Habitat Partnership initiative with LVAS was begun in 2020 with Mike McCartney, Scott Burnett, and Tim Kita, the success of this species at Minsi Lake has been phenomenal. Thanks to LVAS volunteers, a large and growing Purple Martin colony can now be seen at Minsi.

Over the past five years, five 18-unit condo towers have been installed. Occupancy this nesting season in those condos (36 of which are new this season) is over 90% with nesting pairs in 80 of the 90 condo units. At Minsi Lake, it really is a build it and they will come situation. The lake provides an ideal habitat for these birds of greatest conservation need—a shallow, warm water lake teeming with dragonflies and other food sources.

There is lakeside space at Minsi for eight more 18-unit Purple Martin nesting towers.

Northampton County Parks and Recreation will fund three more towers at the Lake for next year’s nesting season, and Friends of Minsi Lake will have funding for the remaining five towers.

The expanded Purple Martin project at Minsi Lake means more volunteers will be needed to maintain and monitor the nesting condos over time. The Northampton County Parks and Recreation and LVAS partnership now manages 108 condos in six nesting towers—five at Minsi Lake Park and one at Louise Moore Park. Next year, they’ll be tasked with 144 units, which the small team of dedicated volunteers have agreed to do. If the Purple Martins indicate there’s continued need for nesting cavities at Minsi, up to five more towers will be provided the following year—for a total of 13 Purple Martin condo towers and 234 units to maintain and monitor from March through September.

Maintenance involves removing the PVC nesting gourds from their towers after each season, hosing them out and storing them at a nearby Parks and Rec facility. The gourds are then brought back to the lake in late winter. Pine straw is placed in each condo and the condos are attached to the towers in numeric order for recording nesting data in each unit throughout the spring and summer.

Monitoring during the nesting season requires one or two volunteers to visually check each of the 18 condos hanging from the towers by lowering and raising the racks. Observations are then recorded on a datasheet that is eventually shared with several national databases to track Purple Martins and the community and citizen conservation science needed to sustain them here in the East.

After hatching, only federally licensed bird banders can physically handle and weigh, measure and band the Purple Martin chicks when they are several weeks old. Volunteers are still needed to shuttle chicks in baskets back and forth from their nests to the banding station set up next to the towers.

Northampton County Parks and Recreation needs LVAS continued support to help with installation labor, monitoring, maintenance, winter storage, and, of course, all the banding and data collection done each nesting season. If anyone is interested in volunteering their time to this project in 2025 and subsequent years, please send an email to James Wilson, Recreation & Conservation Specialist for Northampton County Parks, at jwilson@norcop.gov.