Towheeblog

Here is one of the many Common Nighhawks we saw in our recent visit to Malheur National Wildlife Refuge.  This one was napping on the porch railing of a Field Station dorm.  Common Nighhawk (Chordeiles minor) is one of 130-plus species in the Order Caprimulgiformes.

We saw these birds–recently returned to Oregon from South America–in flight, resting, and heard their vocal and flight sounds.  Their flight calls are a raspy “peent.”  And when they dive downward from a flight more than 100 feet over the earth their wings make a booming sound as the bird pulls up and begins to climb again.  The sound apparently comes from the vibrating wing feathers.

The nighthawk has a tiny beak and very long wings.  Its buoyant flight can be surprisingly slow or high speed.  It eats by intercepting flying invertebrates and swallowing them whole.  Because they fly around and deliberately hit insects, their “windshield” needs protection from bug-splatter.  The protection is a series of fine feathers in front of their eyes.

While at Malheur Field Station our field trip from the Rogue Valley Audubon Society was treated to a mist-netting demonstration by Duncan Evered.  He and his wife, Lila, caught TWO nighthawks that we could see at close range.  The nighthawk face: small beak, large mouth, big eye.  The bird feeds mostly at dawn and dusk, thus the large eye for maximum light gathering.  The beak may be used primarily for feather preening.

The nighthawk gathers in insect food and eventually it swallows.  When this bird was captured in the mist net he still had some insects unswallowed.

The Common Nighthawk is less than a foot long, its wingspan about two feet.  When the bird coasts in to land it must quickly fold those wings onto its body, then plunk down onto a resting place.  The nighthawk has very small, weak feet.  It doesn’t perch or grab a limb, it settles onto its underside like a duck or loon.

This species nests over most of the continental U.S.and southern half of Canada.  It winters in most of the nations of South America but little specific data exists on its wintering locales.  The nighthawks of Malheur arrive at the beginning of June and the adults begin leaving in the first half o August.  The young follow shortly thereafter.

If you look carefully at this picture you will see the elongated middle toe on the nighthawk’s foot.  This toe has evolved to have a series of fine teeth which are used to comb the fine feathers around the bird’s copious gape.  This portable comb removes the insects and insect parts that stick to the bird’s front grill.  This fine photo was taken by Tim Simonsen during the mist-net demo.

SOME PHOTOS OF NIGHTHAWKS IN FLIGHT FROM 2010 VISIT TO MALHEUR.

REFERENCES:

Birds of North America Online.

NIGHTJARS OF THE WORLD.  Nigel Cleeve. Princeton University. 2010.