Archive for March, 2017

31
Mar 17

Tree Swallows at Wylie Slough

Tree swallows have blue-green back plumage and a black eye mask. Their undersides are white. Note how long the primaries are on this bird, extending to beyond the tail when folded. (G. Thomas Bancroft)

Tree swallows have blue-green back plumage and a black eye mask. Their undersides are white. Note how long the primaries are on this bird, extending to beyond the tail when folded. (G. Thomas Bancroft)

A clear sweet high pitch whistle came through the air. It sounded a little like a whine that moved into a gurgle and then to a chirp. The soft sound began again after a short pause. The sun was out and the air cool as I walked along the dike at Wylie Slough in Skagit County. It was only the third week of March, and I was surprised to hear the song of a Tree Swallow at this time in Washington. I scanned the branches for this small insectivores bird. They call from a perch near a possible nesting cavity.

The white underside of the Tree Swallow shows clearly as this bird grips to a small twig. (G. Thomas Bancroft)

The white underside of the Tree Swallow shows clearly as this bird grips to a small twig. (G. Thomas Bancroft)

An iridescent green streak shot from a branch, its long pointed wings propelling the bird forward. The swallow began to do acrobatic twists and turns as it attempted to catch insects on the wing. The bird flew out over the marsh, only a few feet above the brown vegetation, looped around a dead tree that rose out of the shallow water, twisting to the right and out of sight.

Wylie Slough is near the outlet of a Skagit River branch. A few years ago, this area was restored to tidal wetlands, removing dikes that had allowed part of it to be farmed, reestablishing tidal flow, and creating habitat for salmon and wetland birds. The dike runs several miles through this wetland and provides excellent viewing of the restoring wetlands.

A tree swallow giving its high pitch song near a nest box along Wylie Slough in Skagit County, Washington. (G. Thomas Bancroft)

A tree swallow giving its high pitch song near a nest box along Wylie Slough in Skagit County, Washington. (G. Thomas Bancroft)

The tree swallow flew in past my head, only a dozen feet away, and landed on a dead branch, looking away from me. The bird began to preen its feathers, twisting its head to grab individual feathers with its delicate bill and pull them through, straightening the barbules, making sure the feather functioned properly. The swallow crunched its neck in contortions to preen feathers along its back.

A tree swallow peers down from a perch on a dead snag at Wylie Slough along the Skagit River. (G. Thomas Bancroft)

A tree swallow peers down from a perch on a dead snag at Wylie Slough along the Skagit River. (G. Thomas Bancroft)

A second bird alighted just inches from the first and began to sing softly, a mated pair. A small wooden bird box was attached to the trunk of a red alder 10 feet off the ground. The pair had appropriated this location for a future nest. Several woodpecker holes were in the dead trees, and this pair could choose to use one of them. I left the pair resting on the branch and continued down the dike.

A nesting box hung from another tree at eye level, and I stopped to watch if this one had a prospecting pair. Two minutes later, a swallow swooped low over the open water beyond the tree, twisting a few times, before flying onto a knot above the box. It sat, staring down at me, bending its head to the side as if it wasn’t sure what I was. The bird stayed only a second before dashing off in the opposite direction, but in less than a minute it returned, quickly followed by a second one. One bird flew down from the perch to hang on the side of the box, sticking its head in and out of the hole, but never fully entering the cavity, before it flew out on a foraging trip.

Over the next week or so, many more tree swallows will return to this wetland. The abundant dead trees in the recently flooded fields should be full of woodpecker holes and would provide many places for swallows to nest. If sites are available, tree swallows will nest in dense numbers, just defending the cavity and a small space around it. I stopped to listen to a bird give its high pitch song, thinking that spring is rapidly progressing in Washington. In two days, it will be the spring equinox.

A tree swallow sits crosswise on a dead branch. The blue-green feathers of its head glisten in the sun and its white breast feathers so their shoft texture. These insectivorous birds use keen eye-sight to catch flying insects. often foraging over wetlands. (G. Thomas Bancroft)

A tree swallow sits crosswise on a dead branch. The blue-green feathers of its head glisten in the sun and its white breast feathers so their shoft texture. These insectivorous birds use keen eye-sight to catch flying insects. often foraging over wetlands. (G. Thomas Bancroft)

24
Mar 17

A Throng of Snow Geese

Snow Geese congregate in a field at Hayton Reserve grazing on the grass and digging up roots. (G. Thomas Bancroft)

Snow Geese congregate in a field at Hayton Reserve grazing on the grass and digging up roots. (G. Thomas Bancroft)

The cacophony was loud even with all the windows closed in my car, so I opened them to take in the cackle. The car filled with honks, guffaws, and the fresh sweet damp air of a sunny day in late March. I parked quickly and jogged to the post and rail fence that bordered the dirt road. Beginning just 50 feet beyond the barrier stretched ten acres of moving, bobbing, and honking white; 5,000 or more snow geese covered the wet field like a quilt. A hundred people leaned against the fence, watching this mass of birds jockeying to be in the right place. The geese were like a swarm of humans covering a high school football field after the homecoming game.

An adult snow goose in white plumage stands alert to check for possible danger before returning to feed. A few black primaris stick out from the folded wing. (G. Thomas Bancroft)

An adult snow goose in white plumage stands alert to check for possible danger before returning to feed. A few black primaries stick out from the folded wing. (G. Thomas Bancroft)

The Snow Geese with brown feathers on their necks and bodies are birds that are less than a year old. They stay with their parents throughout the first winter after hatching. (G. Thomas Bancroft)

The Snow Geese with brown feathers on their necks and bodies are birds that are less than a year old. They stay with their parents throughout the first winter after hatching. (G. Thomas Bancroft)

Large numbers of snow geese winter in Washington’s Skagit County, and I had come to see if any were still here. By late March, they could have started for their nesting areas on the Arctic Coastal Plain of Alaska. These geese roam the Skagit Flats throughout the winter, grazing on grass, sedges, and willows, or eating leftover potatoes or spilled grain, or digging up tubers and roots. This flock stretched for several hundred yards back into the field and at least 400 yards wide.

 

Individual birds standing on the ground were mostly white, their black outer wing feathers being covered by body feathers. Their pink bills and dark eyes gave contrast to the white body feathers. Many still had a little light brown on some feathers; these were young hatched last summer. Small to large groups came in from the east to land with the expanding feeding frenzy, and these flying individuals showed the distinctive black wing tips and white bodies as they approached on fixed wings.

Snow Geese congregate in a field at Hayton Reserve grazing on the grass and digging up roots. Mt. Baker rises in the background and is mostly covered by clouds. (G. Thomas Bancroft)

Snow Geese congregate in a field at Hayton Reserve grazing on the grass and digging up roots. Mt. Baker rises in the background and is mostly covered by clouds. (G. Thomas Bancroft)

Families stay together throughout the winter and talk to each other incessantly as they feed or fly. It is like a clan of humans at a theme park, chattering to each other about what the see, where they are, and where to next. Really, it is about staying together in a crowd. This chatter carried across the field, filling the air with babble like at a noisy crowd at a fair. Groups of two to five would decide to move locations and rise on strong wing beats to 20 to 50 feet above the ground, flying swiftly over the flock before deciding on another place to land. Each then fixes its wings, beginning a gradual glide toward the field, finally holding its wings almost vertically to create strong drag, alighting with a gentle step. Displaced geese were chattering back at the new arrivals, trying to hold onto their piece of the dinner table.

Five snow geese fly together across Hayton Reserve in Skagit County. (G. Thomas Bancroft)

Five snow geese fly together across Hayton Reserve in Skagit County. (G. Thomas Bancroft)

Some started to leave this field and head west to another. Groups of two to fifty birds would rise and fly west over my head and out of sight. Single individuals would come back to fly around the field, relentlessly honking, probably looking for their missing family group. Glacier peak rose above the Cascades to the southeast and the birds that passed in front of this distant volcano looked picturesque against the white covered peak. To the northeast, low hanging clouds mostly covered Mt. Baker but flying flocks with the distant cloud draped mountains reminded me of landscape watercolors in the Smithsonian Museum.

A large flock of snow geese take off in unison and fly a loop around Hayton Reserve in Skagit County. (G. Thomas Bancroft)

A large flock of snow geese take off in unison and fly a loop around Hayton Reserve in Skagit County. (G. Thomas Bancroft)

In a roar of wings and honks, three-quarters of the birds rose into the air at once, thousands jockeying for position, gaining altitude and attempting to stay with their families. I could sense the massive exertion of their breast muscles contracting to pull their open wings down quickly and give them lift. The power of these sprinters oozing across the field as the mass rose at a steep angle into the air made me feel taller and stronger. Those in front of me started south before they turned to fly directly overhead, creating a moving shadow across me. I crooked my neck to watch the white mass pass, wondering how they avoided crashing into each other in the turmoil. The honking made it impossible to hear myself think. The commotion lasted only a few minutes, but the energy filled the air for a long time after the birds had disappeared to the west. A thousand birds still feeding a hundred yards across the field seemed like an anticlimax to the spectacle.

Snow Geese often fly in a dense cloud when they first take off from a feeding location. Only after they become airborne to they form into a more organized flying flock. (G. Thomas Bancroft)

Snow Geese often fly in a dense cloud when they first take off from a feeding location. Only after they become airborne to they form into a more organized flying flock. (G. Thomas Bancroft)

I watched for another 20 minutes as individual geese flew back and forth between the two feeding locations looking for lost comrades. The cacophony had dissipated, but the sweet smell of spring remained.

A small flock of snow geese fly in front of Mt. Baker as they take off from a feeding group in the Hayton Reserve in Skagit County. (G. Thomas Bancroft)

A small flock of snow geese fly in front of Mt. Baker as they take off from a feeding group in the Hayton Reserve in Skagit County. (G. Thomas Bancroft)

A single flying snow goose shows the black primaries and white secondaries of the wings and the aerodynamic nature of their body in flight. (G. Thomas Bancroft)

A single flying snow goose shows the black primaries and white secondaries of the wings and the aerodynamic nature of their body in flight. (G. Thomas Bancroft)

A small flock of snow geese fly directly over head, showing the use of their wings to gain thrust and lift. (G. Thomas Bancroft)

A small flock of snow geese fly directly over head, showing the use of their wings to gain thrust and lift. (G. Thomas Bancroft)