Code |
Code description
(see handbook for full description & use suggestions) |
PO Category - possible breeding evidence
|
10 |
Species observed in breeding season in possible nesting habitat but no other indication of breeding noted. (Care should be used not to include migrants or vagrants.) |
PR Category - probable breeding evidence
|
21 |
Pair observed in suitable nesting habitat during its breeding season. |
22 |
Singing male present (or breeding calls heard) on more than one date in the same place. A good indication that a bird has taken up residence if the dates are 7 days or more apart. |
23 |
Bird (or pair) apparently holding territory. In addition to territorial singing, chasing of other individuals of the same species often marks a territory. |
24 |
Courtship and display, copulation, agitated behavior or anxiety calls from adults suggesting probable presence of nest or young nearby; well-developed brood patch or cloacal protuberance on trapped adults. (For banders.) |
25 |
Visiting probably nest site, or nest building by wrens and woodpeckers. |
26 |
Nest building or excavation of a nest hole. |
CO Category - confirmed evidence of breeding
|
30 |
7 or more territorial males in a block. |
31 |
Distraction display or injury feigning. |
32 |
Used nest found. Must be carefully identified if it is to be accepted. |
33 |
Female with egg in oviduct. (For banders.) |
34 |
Young recently out of the nest, not yet able to fly. Only for those birds incapable of sustained flight. |
35 |
Adult carrying fecal sac. |
36 |
Adult carrying food for young. |
37 |
Active nest with unidentified contents. To be used when the presence of eggs or young in a nest cannot be determined due to nest location or presence of incubating adults. |
38 |
Identifiable nest and eggs, adult incubating eggs, or egg shells found beneath nest. If you find a cowbird egg in a nest, it is a 38 for the cowbird and a 38 for the nest' owner. |
39 |
Nest with young or identifiable dead nestling. If you find a young cowbird with other young, it is a 39 for both species. |