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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 origin and purpose of the beak shield? I have a photo I could send if you think you could help. Thanks in advance. -Nate Bartuska

Hello Nate!

Nasal MarkerCongratulations 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.

Nasal MarkersIn 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,

Deacon
Carly Deacon