Bird Banding at Prairie Ridge Ecostation

This post is brought to you by Hanna Rogers, summer intern for the Citizen Science Unit of the Research and Collections section of the Museum.  Hanna will start her junior year at NCSU this fall and is majoring in zoology.  You may see her this summer at Prairie Ridge, collecting data for a variety of citizens science projects or helping lead educational programs.  Thanks Hanna!

Have you ever wondered how many bird species have flown over head while strolling through Prairie Ridge? They include the Eastern Bluebirds and House Wrens that love to nest in our NestWatch boxes, the Purple Martins that nest in the bird complex by the Outdoor Classroom, and the American Crows that love to eat the crunchy peanut butter from the feeders on the Classroom’s porch. Have you ever wondered, though, how many birds at Prairie Ridge have flown hundreds of miles from Georgia or West Virginia? Maybe all the way from Oregon? The bird banding program at Prairie Ridge helps answer some of those questions!  On June 9th, I had the pleasure of meeting with the small group of binders to learn the process and the importance of the program.

The banding leader at Prairie Ridge, Keith Jensen, arrives at the site at 5am to set up mist nets throughout the grounds. These are very fine nets that hang loosely from poles about 7 to 8 feet apart. The birds have a hard time seeing them, so they fly into the nets and become trapped.  I learned that the nets have swooping pockets–almost like tiny pouches–to catch the birds that fly into the nets, like this female Indigo Bunting:

A female Indigo Bunting is removed from the net. Photo by Hanna Rogers.

The nets have to be high enough off the ground so that larger birds that get caught lower don’t injure themselves.

Once all the nets have been set up, are at the right height, and free of animals, we start our rounds! Every 30 to 45 minutes, the group breaks into smaller groups and checks all the nets scattered throughout the park. When a bird is found in a net, it is safely removed by placing them a “binding grasp,” pictured on this Northern Cardinal:

A Northern Cardinal in the typical two finger grip that researchers use to hold birds. This helps keep them safe as they are handled. Photo by Margaret Cotrufo.

This means taking your index and middle fingers and gently closing the two around the bird’s head.  It’s very important avoid grabbing the bird’s feet when removing them because they are extremely fragile! Once a bird is firmly in hand, you have to gently and quickly remove the netting that is clinging to the bird. The birds are then placed in cloth drawstring bags and taken back to the banding area for review and measurements.

There are a few general measurements that need to be taken before the birds can be released. The most important one is to see if they are already banded or not. Bird bands are tiny aluminum rings that are placed on the bird’s leg, seen here on this male Indigo Bunting:

Banding the leg of a male Indigo Bunting. Photo by Hanna Rogers.

Lots of people worry that these bands affect the birds’ flight patterns, but don’t worry! They are light enough that they don’t make that much of a difference. Each one has a unique code that allows for easy identification once captured. These bands help track migrating birds from different states, and even to see what birds call Prairie Ridge home!

After checking for a band and recording the code if there is one, the next step is to take all the measurements.  They help track the birds’ health over time and subsequent catches and include age, gender, wing length, weight, overall feather coverage, and size/maturity of sex organs. Throughout this process, the birds are still held in the banding position: middle and index finger around the head; pinky and ring finger (or in my case, my second hand) grasping the feet lightly.

I learned very quickly that guessing the age of a bird can be extremely tricky and depends heavily on the time of year, their feather patterns, and the determination of the sex organs. The bird banders use what they like to call, “The Bird Banders’ Bible.” It helps catalogue ways to indicate age and gender by season. To determine age, we looked at the bird’s’ flight feathers, body feathers, and the area were sex organs are located.  It’s easier said than done to be sure. There was some serious debate over the age of one female indigo bunting that was captured that day! Sometimes the age and gender were left as unknown on the data sheet because it’s better to leave it blank then put the wrong information down for the next person who finds the bird.

My favorite measurement to take was the weight! To ensure the most accurate measurement, special holding tubes keep the birds still while on the scale. The tubes came in various sizes to ensure that no harm came to the birds, but provided a great laugh for the group that day. Placed upside down, their tail feathers stick up in the air like this female Northern Cardinal:

Northern Cardinal weighing. Photo by Hanna Rogers.

This position allows for a gentler removal when the weighing is done!

Once all the measurements are taken, a band was placed on the tiny foot of any bird that was not already banded, we checked for signs of a healthy bird, then released them! You do this by placing them in an upright position on the palm of your hand (still using the bander’s grasp). Once you have the all clear, pointing them in an open direction, you release your grasp and they quickly fly away. Later, all the data from that day is placed into a general database that is accessible to other bird binders across the country. This data can help answer questions for researchers, land managers, and conservationists nationwide. It also allows people to observe the species that live or migrate to areas that they live in! Whether it’s the Cardinals you already knew or the Indigo Bunting you saw for the first time, you can always learn something new from an amazing program like this one.

It was a phenomenal experience that I am happy to have been a part of!  I’m already looking forward to more bird banding sessions this summer.  If you happen to see the bird banding table near the Prairie Ridge pond, stop by.  The bird banders are always happy to answer questions and share what they know about the birds of Prairie Ridge!