10-02-14 Bird Field Note

10-02-14 Bird Field Note

October 2, 2014

Kate Stone's Bird Field Note shows Saw-whet Owl tracking, a Brown Creeper caught for banding, and a Nothern Harrier Hawk.

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Bird Field Note Owl Banding, Shrubby Draws, Songbird Banding, Raptor Surveys Kate Stone 9/26/14 Owl

Northern Saw-whet Owl Tracking This week we began trapping Northern Saw-whet Owls. Our hope is to catch migrants, attach temporary radio transmitters to them, and then track them as they migrate south through the valley. In four nights of trapping we caught 18 owls and deployed transmitters on 16.

We use a UV light to help age the owls based on their molt patterns. Owls born this year show a uniform pink reflection under UV light.

This adult owl had an old eye injury and an apparent talon wound on its back. We banded it and released it without a transmitter.

Though we expected the owls to travel down the Bitterroot River corridor, several of them have moved along the base of the Sapphire Mountains. This owl travelled a minimum of 11 miles in one night, ending up in the Threemile Wildlife Management Area.

When possible, we track the owls on the ground to determine roosting habitat and substrate. Without a telemetry unit, we would not have seen this owl roosting just 2 inches off of the ground.

Over four days, this owl moved from the floodplain, up to one of the northern draws, then up to the slopes of Little Baldy, and then back down.

Shrubby Draw Surveys- September 18th Yellow-rumped Warblers continued to dominate shrubby draw surveys. We also detected many more Savannah Sparrows than we had in previous surveys.

The nets are designed to capture small- to medium-sized songbirds, but occasionally they trap small raptors. We caught this male American Kestrel in Sheep Camp on September 17th.

Young American Robins’ pale plumage distinguishes them from their adult counterparts.

We rarely catch Brown Creepers. They tend to stay close to tree trunks, where their plumage provides camouflage as they forage for small insects, spiders, and larvae. Brown Creepers build a hammock-shaped nest, often behind a loosened flap of bark on a dead or dying tree. They glue their nest together with sticky insect cocoons and spider egg cases.