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Birds of San Diego County Checklist

Model Species Account

SH: Observed in or near suitable habitat during the species' breeding season.
SM: Singing male in suitable habitat during the species' breeding season.
JV: Juvenile bird independent of its parents.
MM: Multiple singing males seen or heard at one locality on a single day (please specify number).
AB: Agitated behavior or anxiety calls from adult birds.
PR: Pair observed in suitable habitat during breeding season.
TB: Territorial behavior, such as a dispute or chase by two individuals of the same species.
CB: Courtship behavior such as courtship feeding, breeding displays, or copulation.
PN: Visiting probable nest site (hole nesters).
PB: Probable nest building, by woodpeckers, wrens, or the Verdin.
NB: Nest building or carrying nest material by any species except the woodpeckers, wrens, and Verdin.
DD: Distraction display or aggressive defense of an unseen nest.
UN: Used nest (UN), if you are certain of the builder's identification.
ON: Occupied nest (ON) but contents unknown.
FL: Fledglings (FL) still incapable of sustained flight or downy chicks still following their parents.
FS: Adult carrying fecal sac (FS).
FY: Adult feeding young (FY) or carrying food to them.
NE: Nest with eggs (NE) or eggshells on the ground under it.
NN: Nest with nestlings (NN) seen or heard.
 

Observed, but not breeding (NB): This category is for birds you know are just passing through, like a Vaux's Swift or Hermit Warbler. It is for nonbreeders that may remain through the summer, like a Marbled Godwit or Ring-billed Gull. And it is for local species that forage far from their breeding sites and for which your square has no breeding habitat or colony, like a Caspian Tern or Double-crested Cormorant seen on an inland lake.

Possible breeding

• Observed in or near suitable habitat (SH) during the species' breeding season, as suggested by the species accounts in the Volunteer Handbook.

• Singing male (SM) encountered in suitable habitat during the species' breeding season. Of course, many species sing during migration or when on their wintering grounds, so for these such an observation means little. But for others that normally sing only on their breeding territories while migrants are still passing through, like the Western Flycatcher, this category may be very useful.

• Juvenile (JV) bird independent of its parents, in species where the young do not migrate or disperse while still in this plumage.

• Multiple singing males (MM) seen or heard within the square on a single day. Among nearly all the songbirds, only the males sing. Please specify the number of singing birds detected on your daily field form; if there are many, an estimate is fine.

• Agitated behavior (AB) or anxiety calls from adult birds (think of the "chack" call of a Mockingbird near its nest). Agitation that you induce by "pishing" (possible with many birds when they are not breeding) doesn't count.

• Pair (PR) observed in suitable habitat during breeding season. Use this category with caution; some species, like ducks, will be paired in winter and migration. Two birds seen together aren't necessarily a pair. Watch the birds, and let their behavior guide you.

• Territorial behavior (TB), such as a dispute or chase by two individuals of the same species or a singing male at the same site on two or more field trips at least one week apart. Use this category with caution; some species, like hawks and hummingbirds, will defend a feeding territory or favorite perch while wintering or migrating.

• Courtship behavior (CB) such as courtship feeding, breeding displays, or copulation.

• Visiting probable nest (PN) site, such as a White-throated Swift seen entering a drain hole under a bridge or a woodpecker seen entering a hole in a tree.

• Probably building (PB) a nest, for species like wrens and the Verdin, which build roosting or dummy nests, or woodpeckers, which may maintain holes as roost sites.

• Nest building (NB) or carrying nest material by any species except the wrens, Verdin, and woodpeckers.

• Distraction display (DD) by injury-feigning, typical of ground-nesters like the Killdeer, Black-necked Stilt, and Lesser Nighthawk. Use this category also for aggressive defense of an unseen nest, such as the dive-bombing attacks of the American Avocet and Cooper's Hawk (more intense than the "agitated behavior" described above).

• Used nest (UN) or eggshells found. Use this category only if you are certain of the identification; some species' nests (Black-chinned Hummingbird, Bushtit, Hooded Oriole) are easily identifiable, but many stick cup nests are not.

• Occupied nest (ON) but contents unknown (too high in tree, or in an inaccessible cliff or bank, etc.). Indicated by an adult repeatedly entering a nest or hole (rather than just once as for the "probable nest" above).

• Fledglings (FL) still incapable of sustained flight or downy chicks still following their parents.

• Adult carrying fecal sac (FS).

• Adult feeding young (FY) or carrying food to them. A bird feeding a fledgling cowbird confirms both the cowbird and the host.

• Nest with eggs (NE) or eggshells on the ground under it. Normally, the adults will be very close by; if not, identify with the same caution as "used nests."

• Nest with nestlings (NN) seen or heard. Use this category when you see the chicks in the nest or hear them calling (as from inside a cavity).

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