This past week, WCT bird staff conducted their annual Bobolink banding at nearby farms in the Doe Run area of Chester County. Every year staff visit these farms in hopes of recapturing birds that were fitted with geolocators the previous year and assigning new ones to different birds. These little white capped birds are long-distance migrants who travel from South America to their breeding grounds in the northern United States and Canada. This style of recording device can show us where our grassland birds are going and give us an insight into what habitat they prefer. Grassland birds such as the Bobolink are the most imperiled group of birds in the U.S., and estimates suggest that populations have declined over 40% since 1970. Despite this, our banding locations located on private property are hotspots for these threatened species.
This time of year, Bobolinks have made their way north during spring migration and are trying to breed in the area. This gives our team around a two-week window to band birds before they begin to nest. These days are filled with hope for the species but also frustration. Staff first use binoculars to try to identify previously banded birds and to establish where to setup nets to catch them. With thousands of acres to choose from, it can be difficult to assess where these birds are, given their small size. Discovering which birds were previously fitted with trackers is even more difficult. Thankfully, staff use a color band combination system to uniquely identify individual birds. Even so, our research hinges on bird survival, geolocators staying attached during migration, and recapture of specific individual birds.
It stands to reason that sometimes less-than-scientific language is used in the field. Bobolinks are incredibly smart birds that become even smarter after they have been banded for the first time. The success of the banding program relies on luck, determination, and a whole lot of patience. Despite this, it is a favored day for our bird staff. It is incredibly rewarding to witness flocks of Bobolinks take to the skies to try to impress mates while gracefully diving into shin-high grass only to disappear. These hayfields give space to reflect on the importance of this species, and the innate beauty of their preferred habitat. We are grateful to our partners who allow us to use their properties to prove that birds and agriculture can not only coexist together but thrive.
