Migratory Owl Research at NBNC

On a clear, cool October night, as you sleep in your bed, owls are flying over your home.  It is the migration season for the Northern Saw-whet Owl, and the North Branch Nature Center is joining a partnership of researchers around the country to study this small, secretive bird.  NBNC piloted two banding stations this fall on the Nature Center’s property in Montpelier and in Shelburne, VT.  

Northern Saw-whet Owls are just barely bigger than a soda can (but only a third of the weight).  They hunt the forest for mice while trying to avoid predators such as Barred Owl, which could easily eat them.  Saw-whets are named after their monotonous song: a continuous rendition of whistles that resemble the noise made when a saw is being sharpened.  The owls are strictly nocturnal and despite being relatively common, are rarely seen.  

An owl getting its wing measured, photo by Brian Jenkins

 At the banding stations, owls are caught using special nets, measured, and banded before being released.  The age of the owl is determined by examining the bird’s flight feathers.  Gender is calculated using the wing length and weight.  Through banding, we hope to contribute to the growing understanding of the Saw-whet’s migration.  Learn more about how we band owls. 

Map showing where previously banded owls had been captured

We have already had some interesting findings this season!  On Thursday evening, Oct. 24, two owls were caught that already had bands around their legs.  The first one was banded last fall at a well-known birding destination called Hawk Mountain, 300 miles southwest in Pennsylvania.  The second one was banded just 16 days earlier in Montreal, Canada.  These two birds, caught half an hour apart, have shed some light on the migratory routes of owls as they travel through the Champlain Valley during their journey from the north to the south.

Photo by Brian Jenkins, 3rd Stone Images

The public has also been invited to observe banding both in Montpelier and Shelburne.  To date, over 150 people have visited the banding stations to learn about and see owls.  In between owls, guests have a chance to experience the outdoors after dark.  Wildlife abounds in the night forest, and we’ve seen many wonderful creatures on our late nights outside: skunk, opossum, barred owl, coyote, gray treefrog, porcupine, beaver… and shooting stars.  And most importantly, visitors get a chance to see science in action and deepen their understanding of and appreciation for the natural world.

As the banding season winds down, we’ll continue to post about our progress both on facebook and to our website.  Please visit back for more information about owl banding and other programs at NBNC.

Look-alike Birding in the Champlain Valley

A late-October trip to the Champlain Valley is sure to turn up some “good birds”.  And good birds are exactly what a group with the North Branch Nature Center’s fall trip found as they explored Chittenden and Addison counties this weekend (10/26/13).  Two of the most intriguing finds were rare “look-alike” species that have very similar, more common counterparts.  

 

The first look-alike was a Ross’s Goose, which another group of birders had already located when we arrived to the goose viewing area at Dead Creek.  This species is rare in Vermont and looks like a miniature of its larger cousin, the Snow Goose.  It is easy to see how a Ross’s Goose could be difficult to locate when it is mingling with a flock of thousands of Snow Geese!  In addition to its diminutive size, the Ross’s Goose can also be identied by its shorter, stubbier beak and the lack of a “grin patch” amongst other subtle characteristics.

The difference between Snow and Ross’s Goose is night and day when compared to the next dubious duo.  A mixed flock of dowitchers has been present at the Brilyea Access of Dead Creek for weeks.  The two species are Long-billed and Short-billed, although bill length is rarely an identifying characteristic.  Long-billed Dowitcher is especially rare in Vermont, but either species is unexpected this late into October.  To tell these birds apart takes patience and experience.  A combination of variable traits are used to distinguish them, including but not limited to bill length, body shape, color, pattern, and overall impression.  Our group continued the debate about which species we had seen well after the trip, sharing photos of the puzzling birds by email.  The jury is still out!

Here is our full species list from the trip:

Snow Goose	Short/Long-billed Dowitcher
Ross's Goose	Long-billed Dowitcher
Canada Goose	Bonaparte's Gull
Gadwall	Ring-billed Gull
American Black Duck	Herring Gull
Mallard	Great Black-backed Gull
Black Duck x Mallard (hybrid)	Rock Pigeon
Green-winged Teal	Mourning Dove
Lesser Scaup	Downy Woodpecker
Surf Scoter	Hairy Woodpecker
White-winged Scoter	Blue Jay
Common Merganser	American Crow
Ruddy Duck	Common Raven
Common Loon	Black-capped Chickadee
Pied-billed Grebe	Red-breasted Nuthatch
Horned Grebe	Carolina Wren
Double-crested Cormorant	American Robin
Great Blue Heron	European Starling
Northern Harrier	Yellow-rumped Warbler
Cooper's Hawk	Northern Cardinal
Bald Eagle	Red-winged Blackbird
Killdeer	American Goldfinch
Greater Yellowlegs	House Sparrow