17 November 2008

October Roosting of the Chimney Swift at the River City

Chimney at the Wareham Building on an October morning after the swifts had departed, on their way to foraging about the Missouri River valley.

Chimney Swifts are a common sight in the aerial realm of Omaha in the latter weeks of their seasonal stay. Although the daily skies may have just a few of the feathered bugeaters about, once dusk approaches, there are regular gatherings at the choice chimneys that provide essential shelter and comfort for a chilly autumn night.

Once the Purple Martins finally went southward for warmer climes, it was time to bicycle around to evaluate how swifts were using various chimneys where birds had previously been noted during a few weeks of survey efforts during mid-August to mid-September, 2003. Due to the mode of transportation, there were limitations on the places that were visited, and thus several places which would have had notable gatherings, were not visited.

The scenario was to arrive at a suitable locality at least 30-45 minutes prior to the expected time when the first swift would take a dive into the chimney. This provided some flexibility to see if they were actually present, or whether an alternate site nearby should where to count the birds as they would descend into the roost. Some additional details were the result of being in downtown Omaha at sunrise, when swifts would depart in a staggered manner from the roost they had used overnight. It is even easier to count in the morning, instead of the evening, when a bunch of swifts can quickly enter a chimney - making a detailed count difficult - versus the morning they depart, a few birds at a time.

Roosting Swifts

Omaha has the facilities that provide important seasonal residences for the swifts. A variety of chimneys provide roosts that are essential shelter for hundreds of these birds to spend the night while they eat hundreds of thousands of bugs from the skies of the region during the daylight hours. There are many buildings with important, and useful roosts.

Recognizing the chimneys used by swifts indicates the important roost habitats, useful for evaluating changes and trends in how the extent and conditions of these structures are changing due to urban renewal and building construction.

One thing is certain, there are no new chimneys being constructed, and older buildings are constantly being cleared. Some important structures, have been renovated, and the chimney remains to provide shelter for the bugeaters. The long-term prognosis indicates a steady decline in the extent of chimneys used for breeding and roosting.

These are the details for the last observations for October, 2008, giving the locality, date seen and associated Julian date; the number of swifts counted, and notations of interest:

Benson: 10/01; 275; 225; 9, 45, 75, 20, 67, 5 at dusk at the community center; additional others at chimney's to the west a block or two
Creighton University Campus: 10/01; 275; 105; 105 caught at first a.m. leaving Wareham building, the former O'Keefe building on the east side of campus, in the morning at sunrise
Creighton University Campus: 10/03; 277; 150; 150 caught at first a.m. leaving Wareham building big chimney at 1624 Webster Street; in the morning just before sunrise
Elmwood East Neighborhood: 10/03; 277; 235; into 6.5x6.5 bricks, ca. 4.5 story chimney at Central Presbyterian Church at 55th and Leavenworth
Dundee Place: 10/04; 278; 12; five into Elwood apartments at 100 block of south 49th Avenue; through open circle atop metal mesh cover on the chimney
Cathedral: 10/05; 279; 24; minimum count into the Radcliffe chimney at 38th and Dodge Street
Blackstone District: 10/05; 279; 8; minimal count into chimney at the Colonial residence hotel, after things slowed at the Radcliffe apartment house

Chimney at 1819 Cuming Street. With the ongoing changes to this neighborhood associated with the sprawl of the Creighton campus, it is inevitable that this old, unused building will be razed.

North Downtown: 10/06; 280; 120; caught this number departing 5x5 chimney at 1819 Cuming Street; others had possibly already departed
Elmwood East Neighborhood: 10/07; 281; 350; 1, 68, 280, 9; into the chimney at Central Presbyterian Church at 55th and Leavenworth; done by 7:15
Dundee Place: 10/08; 282; 85; partial count of birds at the Glen Arlo apartment building at Capitol Avenue and 51st Street
Creighton University Campus: 10/09; 283; 185; noted 183 leaving Wareham building chimney just before sun-rise
Creighton University Campus: 10/10; 284; 157; minimal count of 65, 4, 88 caught leaving Wareham chimney just prior to dawn
Benson: 10/10; 284; 132; 127 into 4.5x4.5 bricks chimney at Immanuel Lutheran Church at 2725 North 60th Avenue; 5 elsewhere in the business district
Blackstone District: 10/11; 285; 108; 2, 14, 8, 4, 40, 37, 3 into 4.5x4.5 chimney at the Colonial hotel; also one seen into Tadousac apartment house, not included in number tally; done by 7:05 p.m. on a cloudy evening
Creighton University Campus: 10/11; 285; 289; 106, 142, 38, 3 departing 7.5x7.5 bricks chimney of Wareham in the first of the morning
Elmwood East Neighborhood: 10/12; 286; 120; 2, 102, 14, 3; into the chimney at Central Presbyterian Church at 55th and Leavenworth; done by 7:15 p.m.
Elmwood East Neighborhood: 10/13; 287; 130; 1, 2, 1, 4, 25, 86, 8, 4; counted at most ca. 20, then about 7 p.m. the bunch arrived and were within the chimney in 10 minutes
Old Market: 10/14; 288; 65; ca. 65 total; 3 into chimney at Barry O's pub, 4 into chimney at Upstream at 11th and Jackson, and 3-4 into Bull Durham building at 1019 Leavenworth
Elmwood East Neighborhood: 10/15; 289; 132; 2, 1, 3, 110, 6, 7, 3 into chimney at Central Presbyterian Church; done by 7 p.m.
Hanscom Park neighborhood: 10/15; 289; 5; about 9:20 a.m. from buildings to the north; not seen coming from chimneys while watching for some time
Downtown Omaha: 10/16; 290; 33 caught leaving chimney at west side; 100 south 11th Street
Old Market: 10/16; 290; 104; 46, 31, 27 left chimney at Upstream building in the a.m.; then many returned into chimney on a morning with chilly temperatures in the mid-30s
Blackstone District: 10/16; 290; 54; 54 into tallist 7x7 chimney at 3819 Jones street, formerly Columbian School Apartments built in the 1890s; done by ca. 6:50, with a temp of 52o, a few minutes after sunset
Elmwood East Neighborhood: 10/17; 291; 136; 50, 60, 20, 6; 22 first bunch, then twice that; whole bunch gathered and flew about for a few minutes; whole bunch in within a couple of minutes.

A unique happening took place after the swifts initially entered this oft used chimney. Within a minute after all the swifts had entered the chimney, at least 80-90 were seen leaving the roost and going northward to some other nearby place ... probably the chimney of a house. The alternate chimney was not located during a quick bike-about, since the birds' destination not visible as it some time post-dusk. Obviously the swifts left the chimney since it was not suitable for the night. Perhaps the heating apparatus for the building was being used with cooler temperatures, making the confines of the brick chimney too uncomfortable.

Benson: 10/18; 292; 25; 25-30 total; 10 into Immanuel Lutheran church on the south side; 5 into 6005 Maple Street; others in immediate vicinity; evening sunset temperature was 58o. The roosting activity was done by about 7 p.m.

There were no subsequent sightings of swifts around the city.

End-of-Season Roost Numbers

In considering the final counts for localities where the bugeaters were known to roost, there were several hundred swifts that were present in the final days of their occurrence during the season. There were probably at least 400 at the locales that were surveyed, with an additional number of birds at other places where there are chimneys suitable for roosting (i.e., Drake neighborhood, west Old Market, near south of downtown, south Omaha business district, etc.).

Although the numbers observed are notably less than the extent of flocks present from late August to mid-September, the continued counts exceeding hundreds of swifts at a single roost site, indicates the value of various chimneys for seasonal use by migrating birds.

The birds seen using chimneys on the evening of the 18th, and their certain departure on the following date, correlates with the last known date of occurrence in the Omaha metropolitan area. Based on an evaluation of nearly 1500 records, the last date of occurrence had been October 19th, so the swifts leaving Benson would have been on the same date.

Chimney Swifts will return to the river city in mid-April next year.

Morning view of chimney at Duchesne Academy of the Sacred Heart, which has been consistently used for roosting.

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