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I shot a great looking blue bill this fall that had a leg band and also had a green plastic shield with an "A" marked on it that covered the top of it's beak with a plastic dowl through it. I wanted to know if you could tell me the origination and purpose of the beak shield?
I have a photo I could send if you think you could help.
Thanks in advance.
-Nate Bartuska
Answer:
Hello Nate!
Congratulations on a great bluebill shoot, and great job looking into the history behind this bird!
There are two types of nasal markers (saddles and discs) commonly used to identify individual ducks, as well as to study their local movements and behavior. Nasal saddles are fit over the bill and often have codes on them, while nasal disks are simple plastic figures of various shapes and colors that are installed on each side of the bird’s bill. Nasal markers are efficient methods to identify ducks at a distance without having to recapture them. The Lesser Scaup that you shot was part of a research study conducted by two former Delta students, Mike Anteau and Al Afton during the springs of 2004 and 2005. As Al Afton explained to you, the study documented spring migration corridors used by the ducks as they left Pool 19 of the Mississippi River (a major staging area), and looked at how fast they were traveling through the upper Midwest in relation to their body mass. Mike Anteau’s dissertation explains how a female scaups breeding propensity and reproductive success can be affected by a decrease in lipid reserves, which could explain the lesser scaups population decline. In this case the green nasal saddle on your scaup identified this bird as light in body weight and was captured and banded in the later stages of migration in 2005. The use of nasal markers for this study is useful, however data collection relies heavily on the general public, wildlife personnel, or hunters to report sightings of these color-marked birds or call in their band numbers.
So again Nate, great job calling in your band and thanks for sharing the history of this bird with Delta and other waterfowlers!
For other interested waterfowl enthusiast that would like to read more about this particular research project, please see Mike Anteau’s dissertation at:
http://etd.lsu.edu/docs/available/etd-01242006-093828/
Sincerely,
Carly Michie - Delta Waterfowl Biologist
Al Afton's letter to Nate:
Hi Nate,
Thanks for the email concerning the nasal-saddled lesser scaup you shot in ND.
Yes, the saddle and band were put on at the same time. My former graduate student, Mike Anteau, and I were marking lesser scaup during the springs of 2004 (banded and spray-painted birds) and 2005 (banded and nasal saddles). We were trying to document the spring migration corridors used by birds as they left Pool 19 of the Mississippi River (a major migration stopover area) and determine how fast they move through the upper Midwest in relation to their body mass, which is good index of stored lipids. Lipids are important in fueling migrational flight and for egg production in this species.
We used 4 colors each year to delineate early/late and heavy/thin birds. The green saddle indicates that your bird was a light bird capture in the latter half of the migration period. The A on the saddle indicates that he was captured during the first week of the latter half of the migration period. Check out the 2nd paragraph on page 9 of the attached old progress report for more details on the marking procedures.
We were hoping for lots of re-observations of color-marked birds by the public and other wildlife personnel after they left the Pool each spring, but we rec'd too few re-sightings to do much analysis. Check out Appendix E on page 212 of Mike's dissertation, which can be accessed free on this web site:
http://etd.lsu.edu/docs/available/etd-01242006-093828/
Satellite radios are the preferred method for collecting the data of interest, but we did not have funding then to do that and were hoping to collect some useful data via the color-marked birds. I have obtained funding to implant 10 female scaup on Pool 19 this spring (March 2007) to further pursue these questions and hope to raise even more funding to increase sample sizes of birds radioed.
I hope that answers your questions; thanks for reporting the band to the BBL.
cheers,
Al Afton
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