Next / Previous / Contents / Shipman's homepage

6.5. Band prefix line

A band prefix line defines the first seven characters of the band number for following new-band records. Its general form:

#sssdnnn

where sssdnnn is the first seven digits of the band number.

Long ago, the Bird Banding Lab stipulated that the fourth character of the band number was characteristic of the band size. For example, a size 2 band would always have a number of the form xxx2xxxxx.

Unfortunately, the fourth character for some band sizes (1A, I think) was a space or hyphen. This leads to problems where some banders elide that character and move the first three digits one space to the right, and others leave the space. That leads to an ugly situation where you have to look for two different representations of the same band number.

To avoid this problem, the IBP many years ago stipulated that all digits of the band number be squeezed to the right end of the field. This means a band printed with 123-45678 will be entered as 012345678.

A question mark (“?”) may appear in any column of a prefix, if that digit is unknown or illegible.

Hummingbird bands have only six characters, e.g., T98765 or X12345. In this case, the new band prefix line must start with three spaces, followed by the remaining four characters of the band prefix. So the prefix for band string “T987xx” would be encoded as "···t987" where “·” represents a space character. Similarly, special four-digit “local” bands are used on sedentary endemics in some sites (such as the CIEL MoSI site in Mexico). These are also right-justified, e.g., “·····03” for the string containing band number 0347.

For historical reasons, bands in a string are numbered 1-100 instead of 0-99. The data compiler takes care of this by adding 100 to any band number if the input is 00. For example, consider this fragment of an input file:

#0780439
n98SOSP...
n99SOSP...
n00WCSP...

The Song Sparrow records would be numbered 078043998 and 078043999, while the White-crowned Sparrow would be numbered 078044000.

The last five digits of the band number are referred to as the odometer part because, for new bands ending in 00, the carry from adding 100 to the band number propagates through those digits and no further. For example, if the current prefix is #1234999, a new-band line with a suffix of 00 would result in a band number of 123400000.

If there are any question marks in the odometer part, propagation of the carry ends at the question mark. For example, if the current prefix were #12345?9, a new-band line with a suffix of 00 would be interpreted as band number 12345?000.