2007-2008 Land of O.Z. Winter Hummingbird Season
The 2007-2008 winter season finished with the lowest number of captured hummingbirds since the winter of 2000-2001 (Land of Ortego/Zalk Winter Hummingbirds/); a year when we only maintained 50 feeders. Today, we manage 75 hummingbird feeders during winter and consistently net 9 times during each winter to capture hummers and other wintering birds. Thanks are extended to Susan Heath, Sue Ortego, Bron Rorex and Suzie Ross who assisted with banding.
Buff-bellied Hummingbirds continued to be the most abundant species at the banding station with 51 individuals captured which is close to normal levels. Rufous was the 2nd most abundant with 19 which is about the normal number for a bad winter and about ½ of what is expected during good winters. There were 6 Black-chins which is well below average, 5 Ruby-throats which is below average, and 4 Allen’s & Broad-tails which is what is expected.
Buff-bellies had 18 new birds for the yard and 33 returning veterans. Eight were originally banded during 2006, 12 from 2005, 5 from 2004, 3 from 2003 and 5 from 2002 or earlier. Our most frequently captured Buff-bellied (band # R57800) continued on his habit of being captured by visiting the banding table 7 of the 9 netting sessions. Y44101 who is the “Old Man” (11 years old) of the yard during winter made an appearance in September and October, but was not captured since. The banding station appears to be saturated with Buff-bellies during winter.
Rufous was the 2nd most abundant with 11 new birds and 8 veterans. This is the 4th most we have had during winter and is well below expected numbers, but not part of an apparent long term decline for this site. Two veterans were from 2006, 3 from 2005, 2 from 2004 and 1 from 2003.
Only 6 Black-chins were captured and this is well below expected numbers. This is the 2nd winter in a row of below average numbers for this species. Only 1 bird was new for the yard, and 5 were veterans; 1 from 2006, 3 from 2005 and 1 from 2002. Our team bands significant numbers of Black-chins in the Texas Hill Country during summer and there is no apparent lack of reproduction from this population. The only foreign Black-chinned recapture we have during winter on the Texas Coast is from a population in the Rocky Mountains and we wonder if this is the source for our winter birds. One bander, Susan Wethington, noted below average reproduction for western Black-chins this summer.
Five new Ruby-throats were banded this winter. We have never had a returning winter Ruby-throat at this site. In general, there was a more westward migration of Ruby-throats this fall and the migration at the Land of OZ finished earlier than expected. A Ruby-throat for only the 2nd time was known to survive the winter here.
We caught 5 Allen’s with one being a veteran from last year. This is the expected number for this species.
We caught 4 Broad-tails with two originally banded in 2006 and one in 2005. This is twice the number nearly captured at this site.
We did not capture any Calliope or Anna’s Hummingbirds this winter which was very disappointing. A few Anna’s were reported along the Coast, but Calliope’s were extremely rare this winter.
The banding station continues to be a very significant site for wintering hummingbirds in the eastern United States. Data on returning species provide information on their life history.
So, why did we have lower numbers? The winter had about the same number of freezing days as in past years, but was generally warmer. We maintained 75 feeders as in the past, and the habitat did not significantly change in our area. We do not believe weather was a factor. Our best guess is that the populations supporting our winter grounds had poor reproduction last summer. Our returning veteran numbers are about the same as past years. Further banding and research may reveal the answer.
Winter banding data since we started maintaining at least 70 feeders occurs below. First Number = total individuals captured; Second Number = total returning veterans.
| Species | 01-02 | 02-03 | 03-04 | 04-05 | 05-06 | 06-07 | 07-08 |
|---|---|---|---|---|---|---|---|
| BBLH | 0 | 0 | 0 | 0 | 1 | 0 | 0 |
| BUFH | 32-16 | 51-32 | 59-30 | 59-30 | 53-30 | 56-39 | 51-33 |
| RTHU | 2 | 4 | 8 | 6 | 13 | 22 | 5 |
| BCHU | 15-5 | 5-3 | 11-2 | 22-6 | 30-7 | 11-5 | 6-5 |
| ANHU | 0 | 0 | 0 | 0 | 5 | 0 | 0 |
| RUHU | 36-5 | 14-2 | 29-6 | 17-6 | 39-7 | 35-14 | 19-8 |
| ALHU | 4 | 3-1 | 3 | 4-1 | 9-2 | 4-1 | 5-1 |
| BTLH | 10 | 1 | 1 | 1-1 | 5 | 2-1 | 4-3 |
| CAHU | 3 | 3 | 6-1 | 1-1 | 5-1 | 2 | 0 |
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