26 October 2014

Autumn Season of Chimney Swifts of Eastern Omaha - 2014

The autumn 2014 season of Chimney Swifts congregating at suitable spaces of eastern Omaha was notably different in comparison to previous years.

Swifts were gone from the city skies days earlier than previously noted. Though these bird had migrated to the south, there were warm days and bugs notably present. Temperatures were above average through nearly the end of October. European Starlings were seen "hawking" for bugs in the sky, similar to what swifts did in previous weeks of the year.

A new record for the number of swifts using one chimney occurred this autumn, and it was at the Izard Industrial Zone on September 16th. It surpassed the earlier record counts for a church in the Blackstone neighborhood.

These are the peak counts associated with the results of Omaha swift surveys, conducted since 2003 in the eastern extent of the river city:

  • Izard Industrial Zone on 09/16/2014 - 1530; a magnificent evening count at the CenturyLink maintenance facility chimney along Izard Street, near 43rd Street
  • Blackstone District on 09/13/2011 - 1400; done by 7:55 p.m.; same number as two nights ago at First Central Congregational Church
  • Blackstone District on 09/11/2011 - 1400; multi-sided chimney at First Central Congregational Church at 36th and Harney; massing about and then entered in about five minutes; multiple layers, directions and swirls; counted by groups of ten as they entered
  • Blackstone District on 09/17/2014 - 1385; into First Central Congregational Chimney
  • Izard Industrial Zone on 10/09/2012 - 1350; swarming as they have on the previous two nights; ready vocalization; done by ca. 7:15 p.m. at CenturyLink building
  • Izard Industrial Zone on 10/08/2012 - 1325; vocal as typical on a warmer evening, with some sort of hurry for them to get into CenturyLink chimney; done about 7:25 p.m., with dusk heavy on the scene; counted in groups as they entered chimney at CenturyLink building
  • Izard Industrial Zone on 10/07/2012 - 1325; a surprisingly large, vocal group early into the CenturyLink chimney; done by 7:15 p.m. with bunches counted as they swiftly entered the chimney

The last observation of the 2014 season was eleven swifts seen at Benson on October 15th. Ten of the birds flew southeast of the central building district to an unknown roost, and only one was seen using a particular chimney. Swifts utilize several chimneys in this urban setting, as seen and enjoyed by residents and visitors, as experienced on the streets of this district during October.

This occurrence was earlier than expected, as once there was a cool night or two, the weather moderated, with temperatures in the 70s and frost-free night for seven to ten subsequent days. There were European Starlings flying like swifts hawking for bugs seen after the bug-eaters were gone.

After many years of observation and keeping detailed records, there are enough details to determine some approximate sort of pattern associated with the autumnal gatherings of the swifts at Omaha. There may be many dozens of birds present and using a particular chimney on one evening, yet none the next day at the same time. This was obvious this year, especially at the Dundee at Dodge Street locale. There were an approximate 155 seen on October 13, yet none the next evening.

During the 2014 season, the largest congregations of swifts at roosts occurred nearly three weeks prior to dates when a similar number occurred in 2013. Also, the last known presence of these birds occurred a week earlier than last year, based upon surveys done at the same geographic locale.

There are more than twenty records of occurrence for swifts in Omaha, subsequent to the latest date for the 2014 autumn season. This includes five times when more than one hundred swifts were counted at a particular chimney in the evening.

This is a summary of the autumnal days associated with Chimney Swift occurrence among the urban setting of eastern Omaha, for the past few years. The records are based upon multiple surveys, primarily during the evening hours. Julian date 255 is usually October 12th, with October 21st the latest date indicated.

Julian Date 2003 2005 2007 2008 2009 2010 2011 2012 2013 2014
255 425 850 - - - - 374 - - 90 23 - - - -
256 265 160 - - - - 60 - - 1400 - - 18 - -
257 - - 265 - - 65 - - 25 254 325 220 - -
258 66 - - - - - - 66 - - - - 2 185 44
259 157 - - - - - - 58 - - - - 130 81 1530
260 405 - - - - 25 27 - - - - 504 1 1402
261 80 - - - - - - 304 - - - - 75 9 62
262 462 - - - - - - 243 - - 60 56 12 711
263 325 - - - - - - - - 10 70 480 534 - -
264 460 - - - - - - 495 190 - - 145 135 - -
265 - - - - - - 25 269 - - 45 225 93 700
266 - - - - - - - - 136 16 140 335 - - - -
267 - - - - - - - - 98 65 - - 17 19 200
268 - - - - - - 15 266 220 - - - - - - 342
269 - - - - - - - - 137 1 - - - - 97 372
270 - - - - - - - - 170 - - - - 365 7 200
271 - - - - - - 260 155 - - - - 65 505 - -
272 - - - - - - - - 408 2 - - 260 349 285
273 - - - - - - 155 13 2 - - 225 140 - -
274 - - - - - - 225 724 - - - - 121 33 20
275 - - - - 25 330 - - - - - - 68 306 630
276 - - - - - - - - 178 3 - - 10 53 - -
277 - - - - - - 385 511 - - - - 96 62 330
278 - - - - - - 12 42 - - 430 660 160 110
279 - - - - - - 32 228 15 - - 630 135 150
280 - - - - - - 120 65 - - - - 59 155 55
281 - - - - - - 360 107 130 8 1325 201 121
282 - - - - - - 85 227 140 190 1325 154 66
283 - - - - - - 183 90 - - 90 1350 200 180
284 - - - - - - 289 2 140 - - 626 168 243
285 - - - - - - 397 8 265 65 585 157 23
286 - - - - - - 120 - - - - 17 625 31 165
287 - - - - - - 130 - - - - - - 710 9 2
288 - - - - - - 65 1 - - 4 6 2 11
289 - - - - - - 137 16 - - - - 10 4 - -
290 - - - - - - 191 - - - - - - - - 7 - -
291 - - - - - - 136 1 - - - - - - 147 - -
292 - - - - - - 25 54 - - - - - - 132 - -
293 - - - - - - - - - - - - - - - - 1 - -
294 - - - - - - - - 9 - - - - - - - - - -

There is no effort underway in Omaha to designate and conserve chimney structures utilized by thousands of migratory and breeding Chimney Swifts. The trend continues to be a loss of chimney roosting habitat, with particular spaces lost each year, to the detriment of the birds.

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