Magnolia Warbler |
Rouge River
Bird Observatory Spring banding 2005 |
| Overview Spring
banding 2005 took place on 26 days from 15 April to 29 May.
An average of 17 nets (12 meter equivalent*) were
open an average of 4.6 hours per day. We lost five whole and eight partial
days to bad weather or other circumstances -- just like last spring.
Often our closures were due to wind, but one day it was due to snow.
We banded 366 new birds and had
70
recaptures
of 60 species (includes Ruby-throated
Eastern Towhee
Highlights
Due to the weather, it was a lackluster season. In fact, some people with a lot of spring migrations behind them said it was the worst in decades. Frontal boundaries blocked northbound migrants during much of the front half of the period. Reports of migrants such as Swainson's Thrushes still in Texas when they should have already been passing through the upper Midwest at least let us know the birds were out there somewhere. When fair weather finally prevailed, many birds bypassed this area, resulting in good numbers of migrants north of here, but dull birdwatching in this area. Numbers were down overall, so trend analysis for most species is relatively meaningless. But there were certainly bright spots in spring 2005 banding. Having banded 136 species prior to this season, there isn't a huge potential for capturing new species here at RRBO. So two new species this spring were definitely highlights.
On 4 May, RRBO's first Grasshopper Sparrow
was banded. There are only a handful of records for It's always nice to recapture migrant birds.
The recapture
of passage migrants in the same season is the basis of research on
stopover ecology. The recapture
of migrant birds that nest here (of which we have over 300 records)
between years gives us information on site fidelity. Much, much rarer
is the recapture of passage migrants between years, and this year we had
two such records.
On 22 April, I netted a banded bird that represented and even more rare event. It was a Ruby-crowned Kinglet that had originally been banded on 23 October 2003 in Toronto. To catch someone else's bird is rare, that bird being a kinglet is even more unusual. You can read all about this special kinglet here. For totals of all species, their previous fall means, and the total since 1992, click here. Bird sightings
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*In order to compare different locations or years that may operate the same number of hours but with more or fewer nets, capture rate is calculated by "net-hours." One net hour is one 12-meter net open one hour, or two 6-meter nets open one hour, etc. This rate is often expressed per 100 net-hours for more managable numbers.