Hummingbird Question 1
This is the first in a series of questions where we are going to try to use bird banding data to firm up answers. Data from The Texas Bird Banding Team will be used to address questions.
Question One. Do western hummingbirds which survive the winter in Southeast arrive earlier on their wintering grounds in subsequent years?
General observations indicate hummingbirds do arrive earlier during each year following the first winter. The belief is that first year birds which are the ones that are pioneering wintering in the Southeast do considerable wandering before they find a place to winter. It is logical to assume that they will spend less time wandering in future years and will likely return to their wintering site earlier. Is this fact or do we just remember the ones who arrive early? Let’s see what the data from the Land of Ortego - Zalk bird banding station shows since this is a constant effort bird banding station where capture effort is the same from year to year.
Hummingbird Arrival Date Deviations
The Rufous Hummingbird is the classic western hummer which is most likely to visit homes in Texas.
RUHU
Males = 4 recaptures later and 9 recaptures earlier than original banding
Averages 25 days earlier; early arrivals = 39 days; later arrivals = 8
Females = 3 recaptures later and 13 recaptures earlier than original banding
Averages 32 days earlier; early arrivals = 56 days; later arrivals = 66 days
Overall, the Rufous appears to arrive earlier to winter in years following first banding. The classical pattern is shown from one bird who arrived 13 days earlier than original banding date in its 2nd year, 24 days earlier in its 3rd year, and 49 day earlier in its 4th year. However, there is variation to this pattern and some birds just like to be different. One bird in our study showed up at the same date as original banding in the 2nd year, 26 days later in the third year and 11 days earlier in the 4th year.
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What about other western species?
ALHU
There is not enough returning birds for this uncommon winter species to break it down by sex. 5 birds were recaptured during the year after banding; 4 arrived earlier and one 8 days later.
Average of 28 days earlier than original date of banding one year later.
This is pretty similar to the pattern used by Rufous.
CAHU
One recapture male 57 days earlier than date of banding.
While Calliope’s are almost as common as Allen’s, not many return to the same site to winter in following years. The exception is the data from the bird above. This male returned for 5 years.
BTLH
One recapture male 6 days later than date of banding
Same could be said for the Broad-tailed as for the Calliope.
General summary for all species is that returning early to winter the year following first arrival by western breeding hummers is fairly common, but not consistent with all individuals.
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What about a species which breeds locally in small numbers, has numerous individuals pass through in migration, and has a larger population which winters. Would it have similar patterns as those species breeding to the northwest?
BUFH
Male = 15 arriving later and 18 arriving earlier
Late arrivers average 28 days later; early arrivals average 29 days early
There are some males with plus and minus arrival times as shown by one male which showed up 8 days earlier than date of banding in 2nd year, but 51 days later in 3rd year and 36 days earlier in 4th year.
Females = 1 earlier and 2 later than original date of banding.
There is no predominant strategy to arrive earlier or later than first capture date with the Buff-bellied.
What about Black-chinned which marginally breeds in the area, but is primarily a migrant with a dozen or so birds wintering each year.
BCHU
Male = All 5 arrived earlier than first banding with an average of 31 days early.
Female = 10 arrived earlier and 3 arrived later than original banding date. Early birds were 41 days before banding date and late birds were 48 days late on average. Mean for all females were 20 days early.
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DISCUSSION: Adding to the variation in this data set is that the banding station is only 6 acres and there are residences nearby which feed hummers, so birds might return to the same wintering site to them, but might not be the same as the banding station. They could be wintering in the neighborhood, but not just going back into the war zone with high density feeders and hummingbirds. As a general rule, we do not try to catch hummers near the banding station. However, we did document one BTLH we banded wintering the next year at our neighbors and a Calliope wintering in Houston instead of returning to Raisin.
Thus, it is fairly safe to presume that western breeding hummers wintering on the Texas Coast will likely return earlier the 2nd year to winter, except for Buff-bellied.
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