If you have passed by Miller Farm close to dark, you may have noticed some interesting activity! James Coffman, a certified bird bander with United States Geological Survey, is currently banding northern saw-whet owls at Miller Farm! He has been banding there since mid-October in order to gather more information about the migration habits of the northern saw-whet owl.

img_1405As of right now, Jim has captured and banded 34 northern saw-whet owls & one eastern screech owl. Only one nothern saw-whet was a recapture and it had gained weight, which is a good sign for the coming winter months. Jim is only targeting the northern saw-whet owls from October- March to band as they migrate south for winter and back north for the spring.



How are the owls captured so that they can be banded?

  1. A mist net is set up in a location where the owls travel. The net is made of a very thin fabric strung between two poles. Because of how thin they are, the owls do not see the net and become tangled when they fly into it.
  2. An electronic call is used to lure in the northern saw-whets. Because of this, Jim must be aware of ground predators like foxes, coyotes, & cats. Checking the nets every half hour will keep them away.
  3. Barred & great horned owls also pray upon the saw-whets. If they are heard close by, the nets are closed.

After an owl, or any bird that is being banded, is captured there are several measurements that are taken before the bird is banded & released:

  • Age– Several measurements are taken in order to determine the age of a bird. These are:

    The above image shows the wing chord length being taken from a northern saw-whet.

    • Wing cord length– Measurement of the wing taken from the joint to the longest primary feather.
    • Feather molt– The feathers are examined for loss, new, or wear.
    • Weight– While weight is used to determine age, it is also a very important measurement to determine body fat for the winter months.
  • Sex- The above measurements are also helpful when determining the sex of a bird.

“The three main owls here in the county are mostly stationary in their territory while the northern saw-whet owls migrate. The capture and study of them leads to the understanding of them & their needs. Habitat is key because it holds for them food & shelter,” says Jim. “Miller Farm has varied habitat sections; the section just north of the net site is very thick. This most likely is a great stop over if not a wintering location for northern saw-whet owls. Hence the reason to verify this and promote keeping the habitat in tact.”


Click here for more information on Northern Saw-whet Owls

The northern saw-whet is a very small sized owl with large yellow eyes. It is one of the most common owls in North America and lives primarily in wooded areas. They eat mostly small mammals (usually mice) but will also eat insects as well as other birds during migration.


As mentioned above, this tiny owl migrates. Many will migrate south or to lower elevations for the winter but some will stay in one place. However, every four years, the migration of northern saw-whet owls increase as many more owls fly south. They migrate during the night and will even cross large bodies of water.



Eastern Screech owl that Jim banded while banding Northern Saw-whet owls.

What does bird banding do for conservation??

  1. Flight Patterns- At first, the main use of bird banding was to observe flight patterns. By studying this, people were able to figure out what birds lived in the area year round, what birds migrated, and even where the breeding grounds were.
  2. Habitat, Behavior, & Life Span- Bird banding quickly led to the more in depth study of birds. People began, and still do today, to study the habitat, behavior, and life span of a species. The information gathered from one species can be compared with another to compare competition for food and habitat and how this affects the population.
  3. Hunting Regulations- As time progressed, bird banding became an important tool for understanding the harvest rate of a particular species by hunters. The sample of reported bands by hunters is one factor used to set hunting regulations. This will ensure the population remains stable and does not take a turn towards being over hunted.
  4. Threatened/Endangered Statuses- Banding is a great what on monitoring population and is important when determining an declining species status.
Jim has been banding birds since 1976 and has banded numerous species of birds. He has also maintained nest box trails for eastern bluebirds, tree swallows, purple martins, and the prothonotary warbler. A special thanks to Jim for answering our questions so we could share this with the public!




About Sarah Schott

I have enjoyed hunting, fishing, and the outdoors my entire life. My enjoyment of writing, reading, and teaching others leads me to want to share my passions of the environment. I have also found conservation to be very important and I am well aware of how important conservation choices are! Through my work with the District, I like to deliver information that is helpful, inspiring, and challenging for our readers to make even better conservation choices of all our natural resources!

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