2008 Dan Brown’s Hummer House BCHU Trends
We caught 636 Black-chinned Hummingbirds on 20 June 2008 at the Brown Ranch. This was the 2nd highest hummingbird catch for the Ranch. Songbirds were much lower than normal (<400) and their scarcity allowed banders to focus more intensively on catching hummers. We recaptured about 88 hummers from previous years. This was the 3rd year in a row of lower than expected production of young. There was a severe hail storm during spring 2006 that probably killed birds, there was a major freeze in early April 2007 that probably destroyed all nesting attempts at the time. 2008 had much lower rainfall than normal which should lead to lower production and higher dependency of birds on feeders. Adult male to female sex ratios was about 45% male which is about normal for this site and date. It contrasts greatly with ratios from neighboring ranches and shows the significance of this property by being able to support reproduction of high densities of birds late into the season. Win and Beck ranches nearby feeders had a much higher percent of adult females and indicates that breeding is finishing up for the season earlier at these sites than at the Hummer House.
BLACK-CHINNED HUMMINGBIRD PRODUCTION
BROWN (HUMMER HOUSE) RANCH
CHRISTOVAL, TX
| YEAR | YOUNG | ADULTS | Y:A | %YOUNG |
|---|---|---|---|---|
| 1997 | 30 | 210 | 1:7 | 12.5% |
| 1998 | 83 | 272 | 1:3.3 | 23.4% |
| 1999 | 111 | 336 | 1:3 | 24.8% |
| 2000 | 129 | 227 | 1:1.8 | 36.2% |
| 2001 | 107 | 186 | 1:1.7 | 36.5% |
| 2002 | 147 | 237 | 1:1.6 | 38.3% |
| 2003 | 114 | 403 | 1:3.5 | 22.1% |
| 2004 | 110 | 259 | 1:2.4 | 29.8% |
| 2005 | 163 | 341 | 1:2.1 | 32.3% |
| 2006 | 106 | 319 | 1:3.0 | 24.9% |
| 2007 | 128 | 480 | 1:3.8 | 21.1% |
| 2008 | 150 | 486 | 1:3.2 | 23.6% |
| YEAR | AGE | MALE | FEMALE | UNKNOWN |
|---|---|---|---|---|
| 1997 | HY | 13 | 5 | 2 |
| (230) | AHY | 98 | 112 | |
| 1998 | HY | 43 | 39 | 1 |
| (355) | AHY | 99 | 173 | |
| 1999 | HY | 57 | 54 | |
| (447) | AHY | 168 | 168 | |
| 2000 | HY | 63 | 62 | 4 |
| (356) | AHY | 93 | 134 | |
| 2001 | HY | 54 | 51 | |
| (293) | AHY | 70 | 118 | |
| 2002 | HY | 88 | 58 | 1 |
| (384) | AHY | 106 | 129 | 2 |
| 2003 | HY | 62 | 51 | 1 |
| (518) | AHY | 170 | 232 | 1 |
| 2004 | HY | 69 | 41 | |
| (369) | AHY | 104 | 155 | |
| 2005 | HY | 101 | 62 | |
| (504) | AHY | 153 | 187 | |
| 2006 | HY | 65 | 41 | |
| (425) | AHY | 145 | 174 | |
| 2007 | HY | 82 | 46 | |
| (616) | AHY | 246 | 234 | |
| 2008 | HY | 84 | 66 | |
| (637) | AHY | 217 | 269 (117 OF 163 TAIL WEAR) | |
| 2 recaptures from Win’s | ||||
| WIN | |||
|---|---|---|---|
| 2005 | HY | 9 | 7 |
| (83) | AHY | 37 | 30 |
| (6 recaptures from Dan’s yard at 0.5 miles) | |||
| 2006 | HY | 11 | 4 |
| AHY | 73 | 33 | |
| 2007 | HY | 2 | 3 |
| AHY | 46 | 42 | |
| (3 of 5 recaptures from Dan’s yard) | |||
| 2008 | HY | 20 | 12 |
| AHY | 32 | 101 19% YOUNG | |
| (2 of 9 recaptures from Dan’s) | |||
| BECK | |||
| 2005 | HY | 13 | 7 |
| (100) | AHY | 18 | 62 20% YOUNG |
| (3 recaptures from Dan’s yard at 0.7 miles) | |||
| 2007 | HY | 9 | 4 |
| AHY | 16 | 55 15% YOUNG | |
| (no recaptures) | |||
| 2008 | HY | 10 | 8 |
| AHY | 5 | 80 | |
| (no recaptures) | 47% tail wear | 17.5% YOUNG | |
| DOLLIVER | |||
| 2007 | HY | 1 | 2 |
| AHY | 47 | 46 | |
| (no recaptures) | |||
| LEMON | |||
| 2007 | HY | 3 | 2 |
| AHY | 29 | 30 | |
| 8%YOUNG | |||
| 2008 | HY | 8 | 9 |
| AHY | 26 | 57 | |
| (13 recaptures) | 38/57 tail wear | 17% YOUNG | |
THE END
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