A Continent-wide Chimney Swift Roost Monitoring Project


Morehead City, SC

Thought you would be interested to know that I have just come in from visiting one of my swift roost sites, West Carteret High School in , and there were a gazillion swifts. Actually I estimate over 500 and probably closer to 600. Couldn't believe my eyes! Today my brother who lives about 60 miles NE of me was telling me about seeing (still!) large numbers of swallows on power lines. This prompted me to be curious about the swifts. I couldn't do the Sept. count because we had a large weather system off our coast which was dumping a huge amount of rain along with the wind. Each Sept. its difficult to do this count because invariably we have a tropical depression. All summer we have had the most mosquitos ever and tonight while I watched the swifts, I was covered. Our temperature has been in the high 80s, which is about 20 degrees above the norm. Next week we are due for a couple of days.

I wonder if these swifts included birds migrating from the north, even tho' it hasn't been all that chilly up there yet. The purple martins have been gone from my location since the end of August. They were observed at a large roost in New Bern, under a bridge in Sept. Its estimated that upwards to 10,000 martins gather there. I know in the last days, my martins fly in from that direction. I have 36 Super Gourds and they are full; my neighbor has at least that many nesting in different housing. So over all, there's been lots of food for these insectivores this year. Flycatchers have been gone a month.
Is this evidence of global warming? I wonder.   Douglass Swanson

Delaware, OH

The last migrating Chimney Swifts used Delaware, Ohio for a roosting site on October 10 as two birds dropped into the chimney above One West Winter Street. The most swifts using this chimney occurred on October 4 when 186 birds roosted there.

I started counting roosting swifts on August 10 for the 2007 migration season. I completed 41 counts from three chimneys and the season ended on October 11 when no swifts showed up.  Two popular chimneys were ignored after heavy rains. Swifts quit roosting at the National Guard Armory sometime after September 23, and the United Methodist Church in Galena was snubbed prior to September 9. I hypothesize that ammonia gases percolate from guano deposits after rainwater pools in chimneys. Hopefully, someday, this question will be investigated.

More or Less Swifts in 2007?

Occasionally, people ask me about long term population trends among migrating swifts. I offer the following calculations that contain unknown variables, but the stats are offered, nonetheless.

For each of last five seasons at the National Guard Armory chimney, I averaged the five largest counts for each year since I began taking serious counts in 2003. For example, the five largest counts for 2003 are 1650, 1420, 1100, 1060 and 925. The average for the largest five counts is 1231 swifts, the highest average among five years of counting. For comparison purposes, I called 2003's average one and divided all other averages by 1231 to find relative values.

Below, I list values from five years of counting. Each row shows the year, the range of five highest counts for that year, the average for the five highest counts, and the comparative size of each year's average relative to year 2003.

2003, (1650 - 925) Average = 1231, 1.00
2004, (1020 - 537) Average = 851, 0.69
2005, (680 - 536) Average = 591, 0.48
2006, (430 - 346) Average = 396, 0.32
2007, (769 - 661) Average = 716, 0.58

In conclusion, while comparing the last number in each of the rows, I can say that the population of migrating swifts declined drastically from 2003 until only 1/3 (0.32) as many were counted in 2006. However, the migrating population nearly doubled from 2006 to 2007, recovering to 6/10 (0.58) as many
birds counted in 2003.  Heavy rains can wash swift nests from the walls of chimneys, but 2007 was
extremely dry during the swift's nesting season. Was 2007 a good year for nesting Chimney Swifts?

I think so.  Swift on, Dick Tuttle

St. Louis County, MO

Late this afternoon I watched a large flock (several dozens) of migrating Chimney Swifts hunting over my St. Louis County home (and a couple of my neighbor's homes) at low altitude. Can't say which way
they were heading. The last local neighborhood resident swift that I saw around here was on October 8.

Mike Thelen

Houston, TX

We had an interesting week for the chimney swifts in Houston.

I observed 50-100 swifts (order of magnitude) near the waste treatment plant in Clear Lake at Middlebrook and Space Center Blvd on Friday 10/12.

Don and I counted 78 swifts at St Paul's at 5501 Main St on Monday night (10/15). This was the night that the cold front came through. There was light rainfall while we counted. The swifts entered the chimney early (about 6:35 pm).

On Tuesday night (10/16) we were back at the Beechnut waste treatment ponds, Pershing, and Whole Foods. Several of us observed about 200 (order of magnitude) flying around the treatment ponds. At 7pm they all disappeared. It looked like most of them went west towards Bellaire. We counted 2 swifts at Whole Foods and no swifts at Pershing.

So the question returns - where are all the swifts going? They migrate during the day and roost at night. I checked out some of the schools in Bellaire. Braeburn Elementary School had 6 swifts on Friday (10/19) at 7 - 7:15 pm.

I also noticed that the swifts were flying high over the trees and homes north of Beechnut at the waste treatment ponds on Friday night. There were about 50 swifts (order of magnitude).

We will continue to monitor the swifts for another week. It should be interesting if the cold front comes through on Monday. If the forecasters are correct this will be a real cold front. We will monitor Whole Foods, Pershing, and the Beechnut Waste Water Treatment Plant on Tuesday. Sunset is at 6:41 pm on Tuesday.

Pam Smolen

Waterloo, IA

I know this is late for the official count, but I was encouraged by an Audubon Society member to notify you regarding chimney swifts at our school.

Number of swifts counted: 13
Time (and time zone) 6:30 pm Central Daylight Savings Time
Date: October 7, 2007
Location Orange Elementary School
Address: city, state/province: 6028 Kimball Avenue, Waterloo, IA 50701

Broad description of the site, e.g. school, warehouse, residence, Chimney Swift Tower, etc.:

The swifts were seen flying above our two school wetlands and the surrounding prairie. The observer suspects they might roost in the chimney of our school. We have also reported them to the Iowa
Nature Mapping site.

Carol Boyce, Teacher