Posts Tagged 'black-capped chickadee'

Northern Goshawk at Ambleside Park

I stopped in at Ambleside Park today as part of a tour to some of the north shore’s smaller birding destinations. As I was glassing some European Starlings in a tree situated along the western arm of the pond, a Northern Goshawk made a sudden appearance into the midst of the group.

Northern Goshawk often attempt to capture their prey by ambushing the victim (1). The attack may involve a silent glide to the target from an elevated perch; although, if detected, the bird will propel itself forward in an attempt to get to the prey before it escapes (2, 3). The Goshawk I observed was unsuccessful in its attempt to capture a starling; however, a very brave (or foolish) Black-capped Chickadee rushed to the scene and began scolding the hawk. It was almost made into meal when the hawk rushed forward along the tree branch, exhibiting the persistent and often reckless hunting behaviour that these birds are known for, in an effort to make the best of a failed capture (2). The chickadee was too good for the hawk as it made a quick getaway to a perch out of reach and resumed its scolding.

After the hawk flew off I went to check out the action in Burrard Inlet but on my way back to the car I swung by the pond again. This time I found the Goshawk perched in a conifer on the golf course that makes up the northern bank of the pond…

I’m really enjoying this two week break I have from university thanks to the Olympics; today was my fourth straight day of birding and I’m looking forward to the fifth. This Northern Goshawk was a great bird to look at and to watch it hunting was quite spectacular, though it would have been nice to see it take one of those starlings out of action.

References:

  1. Squires, John R. and Richard T. Reynolds. 1997. Northern Goshawk (Accipiter gentilis), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.proxy.lib.sfu.ca/bna/species/298doi:10.2173/bna.298
  2. Beebe, F. L. 1974. Goshawk. Pages 54-62 in Field studies of the Falconiformes of British Columbia. Br. Columbia Prov. Mus. Occas. Pap. Ser. no. 17.
  3. Schnell, J. H. 1958. Nesting behavior and food habits of goshawks in the Sierra Nevada of California. Condor 60:377-403.
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Maplewood: October 13th 2009

I was not in the mood for homework today and so I decided to head out birding for an hour or two. When I arrived at Maplewood the tide was out so I decided to check out the western area first. Nothing much was going on until I got to the largest of the ponds (the one that usually has ducks). I spotted a Sharp-shinned Hawk flying above the trees to the east; it was being chased by two Northwestern Crows who managed to get a few swipes in before the hawk ducked into the treetops.

The two Long-billed Dowitchers and three of the Greater Yellowlegs that I observed on October 10th and 11th were still present on the mudflats and actively engaged in foraging for food.

On my way out I had a look at the birdfeeders hanging in the fenced off maintenance area and immediately noticed a single Evening Grosbeak. Unfortunately it flew off before I could get any pictures. Song Sparrows, Black-capped Chickadees, Dark-eyed Juncos, House Finches, and a few Spotted Towhees were also at the feeders.

Maplewood: October 3rd 2009

I had an excellent afternoon of birding (when is time spent birding ever not excellent?) at Maplewood Conservation Area last week Saturday. A Bewick’s Wren was active in the brush near the mudflats as well as several Song and one (Sooty) Fox Sparrow. The tide was out and American Widgeon, Northern Pintail, and Mallard were in the shallows close to the water’s edge. Out on the water were several Pelagic and Double-crested Cormorants and a Common Loon (now in non-breeding plumage). A Great Blue Heron was also foraging about 25m away from the viewing area and a Bald Eagle was perched on one of the pylons.

A Belted Kingfisher was perched on branch close to the footbridge that separates the east and west side of the area. I watched as it made three dives into the water but each attempt was unsuccessful and eventually the Kingfisher flew off.

While watching the Belted Kingfisher I noticed a Horned Grebe swimming about in the small bay to the south of the bridge. It preened itself for a minute or two before settling its head onto the feathers of its back and resting. The Horned Grebe appears to be undergoing a breeding range contraction towards the northwest resulting in the species being Blue Listed in the USA (Tate 1986) and “vulnerable” in Quebec (Shaffer et al 1995). In British Columbia no changes in range have been noted (Cambell et al 1990). Both Breeding Bird Surveys and Christmas Bird Counts show declines for the population but, due to methodology used (ex. BBS involves driving along a road which may not be located in prime wetland habitat), these may not be the best tools to study population change in Horned Grebe (Stedman 2000). The biggest threat facing the species in its wintering range is habitat degradation due to oil spills and pesticide accumulation in the ecosystem (Stedman 2000). Horned Grebe is seen as an indicator species for wetland health and in my opinion its population declines can be seen as sign of poor or lower quality habitat in eastern North America; this serves to stress the importance of protecting B.C.’s wetland habitat for the conservation of the species and other wetland organisms.

A group of Double-crested Cormorants were preening, sunning, and resting on a sandbar viewable from the southwest corner of the area.

While making my way back along the southern path on the western side of the property a Cooper’s Hawk flew across the trail and into a group of trees. When it noticed me it flew further east and I followed only to have the bird take flight again. As I continued walking along the path I came across a group of six or seven Black-capped Chickadees which were all actively giving scolding alarm calls. I wonder if perhaps I disturbed the hawk’s hunt and thus forced it into a poor position that made it noticeable to the Chickadees which then must have notified almost every other bird in the immediate area.

In contemplating my incident with the hawk and what I have learned about the threats facing the Horned Grebe it is clear that we all have some measurable and ultimately avoidable affect on birdlife. Had I chosen not to stop and stare at the Cooper’s Hawk it might have had a more successful hunt and if we, as individuals, make a similarly small change in our lifestyles regarding agricultural products and the use of pesticides the Horned Grebe and many other birds would be better off.

References:

Tate, J. 1986. The Blue List for 1986. Am. Birds 40:227-236.

Shaffer, F., P. Laporte, and M. Robert. 1995. Rapport sur la Situation du Grebe cornu (Podiceps auritus) au Quebec. Tech. Rep. no. 242. Can. Wildl. Serv. and Environ. Canada, Québec Region, Ste. Foy.

Campbell, R. W., N. K. Dawe, I. McTaggart-Cowan, J. M. Cooper, G. W. Kaiser, and M. C. E. McNall. 1990. The birds of British Columbia, Vol. 1: introduction and loons through waterfowl. R. Br. Columbia Mus. Victoria.

Stedman, Stephen J. 2000. Horned Grebe (Podiceps auritus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.proxy.lib.sfu.ca/bna/species/505doi10.2173/bna.505

Maplewood: September 26th 2009

I was at Maplewood again around midday today. As soon as I arrived at the mudflats I heard the call of an American Pipit (a low series of high, clear or jingling phrases tseewl-tseewl-tseewl . . . or pleetrr-pleetrr-pleetrr and other variations; given in flight for up to 15 seconds according to Sibley’s). There were three present foraging on the mudflat about a metre from the water’s edge. About five minutes after I arrived, however, they took flight to the South. Scanning the ducks present revealed the usual mix of American Widgeon, Northern Pintail, and a few Mallards that have been here for the past couple of weeks.

Two ducks soon caught my attention though. My instinct told me they were Blue-winged Teal but I decided to consult my field guide before positively identifying the two birds as they were in non-breeding plumage and my confidence at ascertaining the correct ID in this state is still a little sketchy. They were indeed Blue-winged Teal. The ducks were on the water close to shore about twenty metres north of the viewing area. Early August into mid October is when this species migrates through British Columbia (Cambell et al 1990). For many their final destination for the winter is northern South America although a larger proportion of birds banded in western provinces and states tend to be found in Mexico (Rohwer et al 2002).

Once again I didn’t have enough time to see what was going on the western side of the area so I went straight for the bird feeders near the entrance. Their wasn’t as much activity as I had seen yesterday evening but several species including Black-capped Chickadee, House Finch and Song Sparrow visited the seed while I was there. A male Downy Woodpecker also ate some suet before flying off into the trees.

I often feel that I learn far more about the world when out birding than I do while reading a textbook or attending a lecture…

References:

Campbell, R. W., N. K. Dawe, I. McTaggart-Cowan, J. M. Cooper, G. W. Kaiser and M. C. E. McNall. 1990. The birds of British Columbia. Vol. 1: introduction and loons through waterfowl. R. Br. Columbia Mus., Victoria.

Rohwer, Frank C., William P. Johnson and Elizabeth R. Loos. 2002. Blue-winged Teal (Anas discors), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.proxy.lib.sfu.ca/bna/species/625doi:10.2173/bna.625

Maplewood: September 25th 2009

I was able to find the time to visit Maplewood Conservation Area this Friday evening. The bird feeders in the fenced off maintenance/gardening area near the entrance had been stocked full of seed so there was a fair bit of activity occurring. Black-capped Chickadees, Song Sparrows, and a few Spotted Towhees were, of course, present. A male and juvenile Downy Woodpecker was also there feeding on peanuts. This is the first time I’ve seen a juvenile Downy Woodpecker at Maplewood this year. I wonder if it is the offspring of a resident pair? This seems likely as young birds will remain within their parent’s territory for several weeks and adults are known to drive young other than their own form their territory (Lawrence 1967). Also present near the entrance were several Yellow-rumped Warblers (all in first winter plumage), Ruby-crowned Kinglets, juvenile Cedar Waxwings and American Robins, as well as a Red-breasted Sapsucker.

I didn’t have enough time to walk the paths on the western side of the property so instead I made my way to the mudflats. Northern Pintail, American Widgeon, Mallard, and Canada Goose were all accounted for.

References:

Lawrence, L. de K. 1967. A comparative life-history study of four species of woodpeckers. Ornithol. Monogr. 5: 1–156.

Maplewood: September 12th 2009

I spent about two hours during the evening at Maplewood Conservation Area and it was slow… very slow. I usually check out the mudflat first and today there were quite a few American Widgeon as well as a couple of Mallards and several Northern Pintails.

During this time of year Gulls begin to show non-breeding plumage; such as this Ring-billed Gull foraging in the shallows:

A slow birding day is often a good time to reflect and appreciate some of the more common, ever present, species of birds such as the Black-capped Chickadee. As summer turns to fall chickadees form flocks of six to eight birds; although, in areas with abundant sources of food, such as suburbs with bird feeders, larger groups will develop. Chickadees will cache food so that it can be retrieved at a later date when needed. This mostly occurs during autumn; though, birds may store food at any time of the year. This may play an important role in the survival of the bird during winter; particularly northern populations (Smith and Susan 1993). It has been found that Chickadees can remember a particular cache site up to a month later (Hitchcock and Sherry 1990). During very cold nights Black-capped Chickadees can enter a state of regulated hypothermia in which they slow their metabolism and thus lower their body temperature by ten to twelve degrees centigrade (Chaplin 1976). This allows them to conserve precious energy.

The day wasn’t a complete bust though; near the westernmost pond I located a female Merlin sitting at the top of a tree. As I went to take my camera out of my backpack the bird swooped after a small songbird, likely a sparrow or finch, and proceeded to chase it west across a grassy area. The hunt was unsuccessful and the Merlin continued flying west.

References:

Smith, Susan M. 1993. Black-capped Chickadee (Poecile atricapillus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu.proxy.lib.sfu.ca/bna/species/o39

Hitchcock, C. L. and D. F. Sherry. 1990. Long-term memory for cache sites in the Black-capped Chickadee. Anim. Behav. 40:701-712.

Chaplin, S. B. 1976. The physiology of hypothermia in the Black-capped Chickadee Parus atricapillus. J. Comp. Physiol. B. 112:335-344.