Nasal marks are wild bird identification devices similar to rings used for banding. This device is used in anatidae, such as teal, so that it can be identified from a distance, more effectively than with a ring. This technique has been used since the early 1990s in Europe and the 1970s in North America.
The nasal marks are cut into bovine earrings, and usually colored. For anatidae, the team of David Rodrigues, of the Polytechnic Institute of Coimbra in Portugal coordinates colors and identification numbers, a different color being assigned to each nesting site (usually a wetland for anatidae) .
Anatidae that do not have nasal septa, a nylon thread is passed through the nostrils and the mark is attached to the beak. code edit code
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