Cooper's Hawk - Accipiter cooperii
The quick agile accipiters also include the Sharp-shinned and Northern Goshawk.
The bird is named after William Cooper, a hunter who supplied ornithologists with specimens during the early 19th century.
The female is larger than the male, an example of sexual dimorphism, an attribute perhaps related to the large size of the eggs.
The short rounded wings of the accipiters are well-adapted for quick maneuvering in dense forests. Falcons and Buteos are not capable of the bursts of weaving flight through dense brush. If the prey is not taken after a short chase, the pursuit is ended. Surprise, not endurance, is the hallmark of an accipiter.
Cooper's Hawks breeds throughout the southern half of the Rockies. The hawks migrate according to a timetable set by the movements of their passerine prey. Passerines are taken on the wing and the hawk usually takes the prey to a "plucking" site prior to eating.
I have never identified a Sharp-shinned Hawk. However, I have identified a Cooper's Hawk on 16 occasions in my Discovery Rise backyard. Since differentiation of these two accipiters is notoriously difficult, perhaps some of the Cooper's, might be Sharp-shinned.
The chart above shows the months when a Cooper's Hawk was identified in my backyard. Not unexpectedly, the most sightings were in May, a month with very high passerine traffic at my feeders. I have not identified a Cooper's Hawk in November, January or February. Perhaps their migration takes them south during the winter.
References
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.
Dunne P, Sibley D, Sutton C. Hawks in Flight. Houghton Mifflin Co. Boston. 1988.
Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.
Sibley David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.
Scotter GW, Ulrich TJ, Jones EJ. Birds in the Canadian Rockies. Prairie Books. Saskatoon. 1990.
Tudge Colin. The Bird. Crown Publishers. New York. 2008.
Canada Goose - Branta canadensis
There are at least 11 subspecies of Canada Geese and the largest is twice the size of the smallest. The largest, Branta canadensis maxima, nests in the prairie wetlands and the smaller races nest further north.
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| Inglewood March 24, 2013 |
Nests are mostly on the ground by water, but more interesting locations include old Osprey nests on poles and the tops of Muskrat and Beaver lodges.
Canada Geese mate for life and survival is recorded for up to 28 years. Every spring, after scouting out a satisfactory nesting site, our local geese build a nest and lay eggs in April and May. The average clutch is 5 to 6 eggs (range 2 to 11). The nest is lined with down. The mother sits on the nest while the father stands guard and the goslings hatch about a month later (25 to 30 days). The young birds fly by about 9 weeks and remain with the parents until the following spring.
I came upon the clutch above last year during the first week of May. The nest was built among some low shrubs on a ledge above the Elbow River. I was unaware of the nest until I was about 10 meters away. The Mother goose and I startled each other and we both flew. I flew several inches straight up and the Mother flew to the other side of the river. I took a few quick photos and left, and for the rest of the season, I avoided the site.
There is a stone nestled in the center of the eggs. I suspect the stone is a heat sink and helps maintain the temperature. During cold winter nights on the prairies, the settlers heated up a stone on the fire place and placed the stone under the blankets at the foot of the bed to keep their feet warm. Perhaps they learned this from the Geese?
Geese are great dry land walkers. Their legs are positioned in the middle of the body to facilitate walking on land. Their bill is suited for clipping grasses and eating seeds on the ground.
The goose in the two photos above was in Mallard Cove, off the Elbow River, on April 22, 2013. There have been two geese in the cove on most occasions since, but I have not spotted a nest.
References
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005
Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998
Sibley David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.
Tudge Colin. The Bird. Crown Publishers. New York. 2008
Grosbeaks are a member of the finch (Fringillidae) family.
Pine Grosbeaks usually breed in the Boreal Forest of Northern Canada, where there is snow for two thirds of the year. They are winter visitors to my backyard. The come south to look for food. Periodically, during irruption years when seed crops fail, they nest in the warmer southern regions of the province.
Years ago, when my daughters were kindergarten or early elementary age, a Pine Grosbeak was stunned after flying into one of our windows. The berries they eat ferment over time and the alcohol content is enough to impair flight. This was a likely factor. The bird could not fly but could walk and the grosbeak paced back and forth in a trench behind our house. My daughters named the bird "Pacer." A few hours later the bird flew away, with my advice never to drink and fly again.
This grosbeak enjoyed some seeds that persisted through winter on a Japanese Tree Lilac in my garden.
References
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.
Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.
Sibley David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.
Tudge Colin. The Bird. Crown Publishers. New York. 2008.
Northern Flickers
Flickers may have red (Western distribution) or yellow (Eastern distribution) feathers, but both groups are present in Alberta and these groups interbreed regularly such that I see intermediate orange-coloured feathers on a regular basis.
These birds feed on the ground or in trees for insects. They like to peck away at ants. They do not excavate trees as much as other woodpeckers and their bills are slightly curved. This shape allows them to probe and explore crevices.
I hardly ever see two flickers together, so when I spotted these two in my back yard, I knew something was up. This was confirmed when the birds allowed me to photograph them for about 5 minutes from my deck. Most flickers are very skittish and fly off as soon as I open a door to the backyard. Clearly these birds were preoccupied with something compelling enough to ignore me.
A territorial display played out for over five minutes. The birds squared off with bills in the air and fenced back and forth around bushes. Each bird tried to stand its ground and until the end, neither bird turned away. When one bird was more assertive the other hopped back. This back and forth action happened over uneven terrain and between bushes. Finally one bird gave up, turned away, hopped several meters to a clearing, then seemed to nonchalantly browse for insects for a few minutes, but after satisfying what looked like some "loser's pride," the beaten bird skulked away.
The hole in the dead tree above is a Flicker nest that I spotted by the Elbow in early April. The hole was about 10 meters above ground. Breeding starts in March in Alberta.
A few days later, April 9th, 2013, I saw the flicker in the nest.
References
The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.
Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005
Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998
Sibley David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.
Tudge Colin. The Bird. Crown Publishers. New York. 2008
Hooded Mergansers
Mergansers are divers. Their beaks are different than ducks. The narrow saw-edged beaks help them catch and hold fish.
Mergansers often nest in cavities, including tree holes and they are reported to favor the nests of large woodpeckers. In my neighborhood the largest woodpecker is the Pileated and the usual nest is about thirty meters above the ground in a dead tree or a utility pole. Perhaps someday I will see a Merganser and a Pileated Woodpecker sparring for this location.
References
Sibley, David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.
Tudge, Colin. The Bird. Crown Publishers. New York. 2008
