Age (Year Class) Codes

NUMERIC CODE	ALPHA CODE	ALPHA TRANSLATION	DESCRIPTION
0	U	Unknown	A bird that cannot be placed in any classes below . Except in cases where data were not recorded or have been lost during the nesting season, ONLY BIRDS BANDED AFTER THE BREEDING SEASON AND BEFORE JANUARY 1 CAN BE CORRECTLY CODED U.
1	AHY	After Hatching Year	A bird known to have hatched before the calendar year of banding; year of hatch otherwise unknown. Example: Banded 1997 - Hatched before January 1, 1997. Birds that would have been coded U on December 31 graduate to class AHY on January 1.
2	HY	Hatching Year	A bird capable of sustained flight and known to have hatched during the calendar year in which it was banded. Example: Banded 1997 - Hatched 1997.
3	J	Juvenile	OBSOLETE, old code used for nestling or recent fledgling, probably mostly translatable to age L but can not be certain. Code still exists in database with old records.
4	L	Local	A nestling or young bird incapable of sustained flight. After a young bird achieves sustained flight it becomes age HY until December 31.
5	SY	Second Year	A bird known to have hatched in the calendar year preceding the year of banding and in its second calendar year of life. Example: Banded 1997 - Hatched 1996.
6	ASY	After Second Year	A bird known to have hatched earlier than the calendar year preceeding the year of banding; year of hatch otherwise unknown. Example: Banded 1997 - Hatched 1995 or earlier.
7	TY	Third Year	A bird known to have hatched in the calendar year two years prior to the year of banding, now in its third calendar year of life. Example: Banded 1997 - Hatched 1995.
8	ATY	After Third Year	A bird known to have hatched prior to two years prior to the year of banding, now in at least its fourth calendar year of life. Example: Banded 1997 - Hatched 1994 or earlier.

 

How Aged Codes

(Codes marked as "current" represent new codes in version 4 of Bandit. Until v.4 is released, continue to use "discontinued" codes)

CODE	DESCRIPTION	CODE STATUS	AGE CODE MOSTLY USED WITH	COMMENTS
AM	Auxiliary Marker on bird at capture	current	Any age	Birds with auxiliary markers (like web tags) and no Federal band or with foreign bands may be micro-aged. Can be used with recaptures for ages beyond SY, TY
BO	Behavioral observation	current	HY, AHY	Includes singing, incubation, mating/copulation, etc.
BP	Brood patch	current	AHY	Generally used for How Sexed, but can be used to age AHY only.
BU	Bursa of Fabricius	current	Any Age	Most useful in waterfowl
CA	Calendar	current	AHY	Intended for use with AHY (instead of Unknown) between January 1st and beginning of normal fledge time, depending on species, latitude. For known adults that can't safely be called SY, ASY, TY, ATY.
CC	Combination of characteristics/measurements	current	Any Age	Characteristics or measurements that, alone, would not be usable. Describe in Remarks
CL	Cloaca	current	Any Age	Waterfowl cloacal exam, male cloacal protuberance, distended cloaca of female shorebirds.
EG	Egg in oviduct	current	AHY	Generally used for How Sexed, but can be used for AHY
EY	Eye color	current	HY, SY, AHY, ASY
FB	Fault bar	current	HY,SY	Uniform fault bar on juvenile tail feathers (Fig. 19 in Pyle, vol 1, Fig. 18 in vol. 2), sometimes in juvenile remiges.
FF	Flight feathers (remiges), condition or color	current	HY, SY, AHY, ASY	Wear, freshness or color of primaries, secondaries or tertials
IC	Inconclusive, Conflicting	current	U, AHY, ASY	Generally used with age U, but can be with AHY or ASY if micro-ageing characteristics are conflicting or inconclusive.
LP	Molt limit present	current	HY, SY (passerines); greater than HY (raptors)	In passerines can distinguish HY from AHY (Fall) or SY from ASY (Spring) in secondary coverts or alula. Or in raptors, among secondaries and primaries (AHY, SY, ASY, TY, ATY)
MB	Mouth/bill	current	HY, AHY, SY	Refers to mouth/bill color, or bill shape, culmen length, striations (hummingbirds), depending on species
MR	Actively-molting remiges	current	AHY	Useful in late Summer/early Fall for AHY in species with partial preformative molt. Not to be used with species that have a complete pre-formative molt.
NA	Not attempted	current	U	Age U only
NF	Nestling recently fledged, incapable of powered flight	current	L	Usually ages L, but HY under certain circumstances.
NL	No molt limit	current	AHY, ASY	In Passerines, can distinguish AHY from HY (Fall) or ASY from SY (Spring) in secondary coverts or alula. Or in raptors, among secondaries and primaries (HY, SY)
NN	Nestling in nest (altricials), downy young (precocials)	current	L	Use for age L only. This does NOT mean an adult who has young in nest.
OT	Other	current	Any Age	Explain how aged in Remarks
PC	Primary covert wear and/or shape	current	Any Age	Primary Covert shape can be used (with experience) for ageing many species. Primary covert wear is especially useful for ageing woodpeckers (Pyle fig. 122)
PL	Body Plumage	current	HY, SY, AHY, ASY	Color of or patterns in body feathers, including head, breast, back, coverts.
RC	Re-captured bird with USGS band	current	Any Age	Can be used with recaptures (including replaced bands) for ages beyond SY, TY.
SK	Skull	current	HY, AHY, (SY)	Most useful for HY vs AHY. Some individuals are slow to pneumaticize and can be called SY after December 31.
TL	Tail length	current	Any Age	Only useful for ageing in a few species.
TS	Tail shape or wear	current	HY, SY, AHY, ASY	Generally, badly worn and/or pointed in HY,SY and less worn or rounded in AHY, ASY
0	cloacal examination (waterfowl only)	discontinued		Combined with code CL
1	adult plumage	discontinued		Included in code PL
2	juvenal plumage	discontinued		Included in code PL
3	eye color	discontinued		Replaced by code EY
A	nestling in nest--no flight feathers present	discontinued		Included in code NN
B	nestling in nest--flight feathers in pin	discontinued		Included in code NN
C	nestling recently fledged, incapable of powered flight	discontinued		Replaced by code NF
F	feather wear in the flight feathers	discontinued		Included in code FF
J	retained juvenal plumage (wispy tertials/notched tail etc)	discontinued		This code overlapped with other codes (molt limit, etc.) and was often misused
L	molt limit present	discontinued		Included in code LP
M	multiple ages of remiges (wing feathers)	discontinued		Included in code LP, often confused with L
N	molt limit absent	discontinued		Included in code NL, often confused with M
P	primary covert shape and/or primary feather shape/wear	discontinued		Partly included in codes PC and FF. This code was mostly misused to mean Plumage.
S	skulling (not including pinhole windows)	discontinued		Replaced by code SK
T	tail shape and tail wear	discontinued		Replaced by code TS
W	pinhole windows (see skulling)	discontinued		Included in code SK
X	not attempted	discontinued		Replaced by code NA
Z	web tag (or other auxiliary marker)	discontinued		Replaced by code AM