A Bird In The Hand: The Science Of Studying Birds

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A close-up shot shows a researcher's hands removing a small bird from a mist nest.
A researcher removes a bird from a mist nest. (Photo courtesy Wyoming_Jackrabbit/CC BY-NC-SA 2.0)

Ornithology is the study of birds, and its techniques have evolved rapidly over the years. Originally, the number one tool of ornithologists were rifles that they used to collect specimens so that they could be observed up close. However, thanks to innovations like Porro prism and Roof prism binoculars, this practice was phased out over time in favor of more humane methods of observation. And for ornithologists, they developed ways to see the birds up close without harming them – and that’s what I’m sharing with you today.

Mist Netting

A researcher removes birds from a mist net at a bird banding station at Murphy-Hanrehan Park Reserve in Savage, Minnesota. A Palm warbler is visible in the foreground.
A researcher removes birds from a mist net at a bird banding station. (Photo courtesy Lorie Shaull/CC BY 2.0)

If you’ve walked around parks like Otto Armleder Memorial Park at the right time of the morning, you might have gotten a glance at something truly interesting and that is a permitted professional in the scientific community performing a data collection method called mist netting!

Mist netting is a technique performed by people permitted by the U.S. Geological Survey, and likely by their state wildlife agency, in order to obtain data about what sort of birds are in the area. From this, they can get other valuable information, like how much breeding is going on, a rough population density of the area, and what birds appear to be succeeding or failing in this habitat. The mist netting method is extremely safe for the birds with an injury percentage of only 0.59%. This is actually the lowest injury percentage among any method used to study vertebrates.

An American Goldfinch is caught in a mist nest. The American Goldfinch is primarily yellow, with black around its eyes and black tailfeathers.
An American Goldfinch in the pocket of a mist-net at Shawnee Lookout. (Photo: Luke Thies)

In order to mist net, the permitted individual gets out extremely early in the morning, oftentimes before any birds are singing so that they can make sure they get a head start on any avian movement. Then once their nets are opened, all they have to do is wait; the birds will come to them. Each net has four to six pockets on it that a bird can fall into at various different heights. Mist nets are made of a very thin nylon to make it hard for the birds to see. The bird just flies into the nest and falls into a pocket.

A Lincoln’s sparrow (left) and a yellow warbler (right) getting ready to be banded at the University of Cincinnati Center for Field Studies. (Photo: Luke Thies)

Once a bird has fallen into a pocket, it tends to get tangled up. So the banders and any assistants have to act quick! Most nets are usually checked every 15–20 minutes. If you wait too long, the birds could get overly stressed out. Most of the caught birds weigh less than an ounce, so any elevated stress level is bad for them!

Bird Bands

A pair of hands holds a yellow warbler. The person is putting a band on the bird's leg.
A researcher places a band on the leg of a yellow warbler. (Photo: Luke Thies)

Once the bird is untangled from the net, they are then placed inside of a bag. This is to help decrease their stress levels; many animals tend to be calmer in dark spaces. The bird is then given a nice shiny band that has an identification number on it. This ID number can be searched by anyone out there, and the band even tells you where you can go to find information out about it.

A zoomed in photo shows two bird leg bands on a person's finger.
Examples of bird bands. These particular bands were used in Kalamazoo, Michigan. (Photo by U.S. Fish and Wildlife Service, Midwest Region.)

One of the largest programs that uses this is called MAPS, or Monitoring Avian Productivity and Survivorship. This is a continent-wide project to unwrap the secret lives of these breeding birds in varying areas.

The MAPS project looks at breeding markers on birds such as a brood patch, which is a lack of feathers along the front of their sternum coupled with a large number of blood vessels to increase heat exchange with their eggs. This lets us understand when and where birds are breeding. Banders look at these physiological signs, the bird’s weight, wing length and molt pattern to save and input into a database later.

An American robin (left) and a female downy woodpecker (right) getting ready to be banded at the University of Cincinnati Center for Field Studies. (Photo: Luke Thies)

Be on the lookout next time you’re walking around a park – you might get a chance to observe some cool science up close and personal! If you’re interested in learning more about birds and the study of them, keep a lookout on the Great Parks calendar.


Luke Thies
Nature Interpreter, Miami Whitewater Forest