Hummingbird banding results - southeastern Michigan

[Allen Chartier]

Birders,

Some of you may be interested in my hummingbird banding results from this summer and fall. I've summarized in general terms below, but have not included data on specific sites. My single "biggest" site is near Battle Creek, where I banded 172 this year (101 last year) and recaptured 40+. Other than this one site, recaptures were down significantly this year virtually everywhere else. 

For context, I have compared 2007 with two previous years (2005 and 2006). Also, to be consistent, I have only used data between June 1 and September 30 for each year, as my banding in May and October is of small numbers (<1% of annual total) and irregular in effort.

Effort in 2007 was 103.25 Trap Hours (TH) and 828.7 Net Hours (NH), compared with 90.75 TH and 1082.6 NH in 2006; and 98.50 TH and 669.2 NH in 2005.

In 2007, overall I banded 720 Ruby-throated Hummingbirds in southeastern Michigan at about 40 sites with 258 (35.8%) hatch-year. Total for 2006 was 575 with 175 (30.4%) hatch year; and for 2005 was 434 with 115 (26.5%) hatch year.

Since I band at multiple sites each summer and fall, a better way to compare results is Birds Per Trap Hour (B/TH) where traps were used, and Birds Per 100 Net Hours (B/100NH) where mist nets were used (one migration monitoring site - Metro Beach Metropark). It is also useful to separate the seasons into Summer (June 1 - July 31) and Autumn (August 1 - September 30).

Summer B/TH (multiple home sites) was 6.86 in 2007, 6.53 in 2006, and 4.84 in 2005.
Autumn B/TH (multiple home sites) was 5.55 in 2007, 4.61 in 2006, and 3.51 in 2005.
Autumn B/100NH (one migration site) was 11.58 in 2007, 7.94 in 2006, and 4.18 in 2005.

Age percentages gives an indication of productivity, and is also helpful to break down by traps vs. mist nets, and Summer vs. Autumn. 

In Summer 2007, 266 were caught in traps (multiple home sites) with 4 (1.5%) hatch year (3 nestlings). 
In Summer 2006, 240 were caught in traps (multiple home sites) with 3 (1.2%) hatch year.
In Summer 2005, 218 were caught in traps (multiple home sites) with 4 (1.8%) hatch year (2 nestlings).

In Autumn 2007, 358 were caught in traps (multiple home sites) with 168 (46.9%) hatch year.
In Autumn 2006, 249 were caught in traps (multiple home sites) with 92 (36.9%) hatch year.
In Autumn 2005, 188 were caught in traps (multiple home sites) with 86 (45.7%) hatch year.

In Autumn 2007, 96 were caught in mist nets (one migration site) with 86 (89.6%) hatch year (good Jewelweed bloom).
In Autumn 2006, 86 were caught in mist nets (one migration site) with 80 (93.0%) hatch year (excellent Jewelweed bloom).
In Autumn 2005, 28 were caught in mist nets (one migration site) with 25 (89.3%) hatch year (poor Jewelweed bloom)

Allen Chartier
amazilia1 at comcast.net
1442 West River Park Drive
Inkster, MI  48141
Website: http://www.amazilia.net
Michigan HummerNet: http://www.amazilia.net/MIHummerNet
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Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food. It doesn't.
It just eats another hummingbird.
---Steven Wright
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