The following is a list of the abbreviations used throughout the records:
ANSP Academy of Natural Sciences, Philadelphia
AFN Audubon Field Notes
AM Audubon Magazine
ASM Audubon Society of Missouri
BB The Bluebird (ASM's quarterly journal)
BL Bird Lore
CA Conservation Area
Co. County
NN Nature Notes (WGNSS newsletter)
MBRC Missouri Bird Records Committee
m. obs. Multiple Observers
R & E Robbins' and Easterla's Birds of Missouri (1992)
RMBS Riverlands Migratory Bird Sanctuary
WGNSS Webster Groves Nature Study Society

Seasonal Status
PR permanent resident; some individuals present year round
SR summer resident; a breeder, between 1 June and 31 July
SV summer visitor; a non-breeder
WR winter resident; between 15 December and 20 February
WV winter visitor; usually present for only a short period of the winter
T transient in spring and/or fall
c common or abundant; observed daily, usually in large numbers
u uncommon; frequently observed, usually in small numbers
r rare; more than 15 records; usually observed annually
ca casual; 5-15 records; occasionally observed
a accidental; 1-4 records; a vagrant
[ ] hypothetical; at least one probable valid record, but has not met criteria
for full acceptance by the Missouri Bird Records Committee (MBRC)
* species formerly occurring in Missouri; now extirpated
# species formerly occurring in Missouri; now extinct
(s) (n)(s)(e)(c)(ne) Area of state in parenthesis - north, south, east, central, northeast, etc.
Observers are encouraged to document sightings of species marked "a", "ca", out of season,
or not listed on the checklist with the Missouri Bird Records Committee at under the MBRC tab.