Raritan Headwaters Association

Why Bird Conservation?

Using the American Kestrel as an ambassador for clean water and land protection, the Raritan Headwaters Association (RHA) has been developing a program to install and monitor nest boxes for the species in the Upper Raritan River Watershed of New Jersey. The program began about 5 years ago and has grown from a handful of nest boxes to over 40 in 2023, with 50 more boxes ready for installation in 2024. In 2021, RHA received a small grant from the Cornell Land Trust Bird Conservation Initiative (LTBCI), which helped the organization build momentum and expand the program to what it is today.

With support from LTBCI, RHA built on its partnership with New Jersey Division of Fish and Wildlife Endangered and Nongame Species Program to install and monitor nest boxes for American Kestrels—a threatened species in the state—across the working landscape of the region. As part of the project, RHA also formalized the partnership with a webpage, developed and distributed best management practices (BMPs) for farms and fields, and recruited volunteers to help build, install, and monitor nest boxes.

Over the past 50 years, Kestrel populations have decreased by over 80 percent in the northeastern U.S., and lack of suitable nesting cavities in open habitats is one of the contributing factors. Through this program, RHA is helping Kestrels find safe places to raise their young in the Raritan Headwaters.

According to Kristi MacDonald, RHA’s Director of Science, “The American Kestrel truly is a watershed ambassador, acting as a charismatic flagship species for broader conservation efforts. This project promotes the understanding that what we do on the land impacts wildlife, water resources, and ultimately, people.”

Spotlight Resources: Collaborative Partnerships, Bird-focused Habitat Management, and eBird

Four people in a field with a nest box. — Volunteers installing a new American Kestrel nest box. Photo credit: RHA

MacDonald was inspired to develop this program while attending a talk at a local Audubon Society preserve. The speaker was Bill Pitts, a senior zoologist with New Jersey Fish and Wildlife (NJFW), who runs the Kestrel Nest Box Project for the state. Something clicked for MacDonald during that talk, and she realized the potential to use Kestrels as ambassadors for RHA’s mission.

She later talked to Pitts about creating a partnership to install nest boxes on public open space and private working lands in the Upper Raritan, and they initiated the program with five boxes in 2019. By 2020, the program had grown to 20 boxes on two of RHA’s preserves and eight private agricultural lands. Through partner meetings made possible due to the small grant from LTBCI in 2021, RHA built new relationships with other land trusts, nonprofits, county parks, and sustainable agriculture organizations. These expanded partnerships led to the identification of many suitable sites for nest boxes, resulting in the installation of boxes on 14 private farms, three land trusts properties, and several sites owned by nonprofits and municipalities.

Along with installing boxes and creating a webpage about the Kestrel Nest Box Partnership, RHA also recruited and trained new volunteers to monitor the boxes during the grant period. From late April through mid-July, community scientists monitored nesting activity every two weeks. Working in teams of two or three, the volunteers carried a ladder to the nest boxes (which are mounted 10 to 15 feet above ground) to monitor Kestrel nesting and assist in capturing birds for banding. Kestrels were banded by Bill Pitts, the zoologist at NJFW who inspired this program. To make the monitoring more accessible, RHA devised extendable poles with cell phone holders to allow some volunteers to see into the nest boxes without climbing ladders.

When the nest boxes were located on publicly owned parks, preserves, and open spaces, the volunteers also entered data from monitoring trips in eBird. Data from eBird were then used to develop and promote improved best management practices for open habitats to benefit birds and pollinators, such as delayed mowing of meadows; this information was also shared with private landowners who installed Kestrel boxes and is an online resource that RHA continues to distribute to other community members to this day.

Making the Connection

A person holding a young bird. — A young American Kestrel. Photo credit: RHA

“Kestrels are ambassadors for the connection between what we do on the land and the health of our water,” notes MacDonald. “This beautiful, tiny falcon spoke to me as a wonderful way to direct people’s attention toward the conservation messages that we’re trying to send,” she explains.

Community members don’t always relate to RHA’s broad mission of protecting clean land and water, says MacDonald; the American Kestrel nest box program helps connect the dots by providing a tangible example of RHA’s work promoting land preservation and stewardship for a healthy watershed. Seeing the charismatic bird species nesting in the watershed helps people build an emotional connection to RHA’s efforts, and this can help open the door to broader conversations about the health of the ecosystem and other ways of maintaining clean water and land.

Advice to Other Land Trusts

A man on a ladder leaning on a nest box pole in a field. — A volunteer monitoring an American Kestrel nest box. Photo credit: RHA

While this program may initially seem to target one species, MacDonald emphasizes all the other conservation values it serves. Its conservation impact extends beyond Kestrels, she says.

However, it has taken several years to build the program and see its impact—success didn’t come overnight. Funding was key in the beginning, allowing RHA to invest in an intern to help build the program, purchase materials for building the boxes, and invest in training volunteers.

Volunteers often do work that land trusts would otherwise have to pay staff to do, so it’s wise to make the initial investment in their training, MacDonald notes. Having knowledgeable and dedicated volunteers on the project, especially during the breeding season, has been key to the success of this nest box program.

Most importantly, the Raritan Kestrel Partnership has taken time to grow and engage new partners and volunteers. Each year new properties have been added, some public open space and some private working lands. MacDonald adds that when potential partners are asked if they would like to participate in helping in the recovery of the American Kestrel, the answer is always ‘yes.’ This opens the doors for conversations about other ways to improve practices on the land to help Kestrels and provide other conservation benefits.

Next Steps

A man holding an American Kestrel. — Zoologist Bill Pitts holding a banded adult American Kestrel. Photo credit: RHA

MacDonald says RHA is seeing banded offspring from their monitored nests coming back to the area to look for their own boxes, so 50 more nest boxes will be installed over the next year, more than doubling the current number. Local volunteers, including two Eagle Scouts, are building the boxes, and as the program expands to more private lands, RHA may ask participating landowners to monitor the boxes on their properties. Experienced nest box monitors will also help train new volunteers.

With a 25% nesting success rate of monitored boxes in 2023, and the number of nest boxes occupied in 2024 already exceeding that percentage, the population of American Kestrels is starting to take flight in the region. Through longstanding relationships with other land trusts and outreach to new landowners identified on tax maps, RHA will find suitable locations for more boxes this season. Building on its years of successful seasons with this expansion, the program is also helping RHA gain ground in promoting an ethic of conservation in the region.