BirdAnalyst
BBS Route · Delaware · BCR 30

Frederica Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 105 species recorded across 48 survey years, still active.

105Species RecordedSpecies recordedDistinct species detected on standard-protocol BBS runs here across all years on record — a measure of survey breadth, not a complete checklist.Full methodology →
48Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1966–2014Span
5Observers

Bird Species Found on Delaware Frederica

Top 40 of 105 species by most recent count. Each links to its species trend.

Species recorded on the Frederica route.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →History
Purple MartinHirundinidae882014+840%1968
European StarlingSturnidae862014+68%1968
American RobinTurdidae622014+186%1968
Common GrackleIcteridae612014-20%1968
Barn SwallowHirundinidae432014+94%1968
House SparrowPasseridae422014-60%1968
Chipping SparrowPasserellidae302014-5%1968
Turkey VultureCathartidae222014+243%1968
Northern CardinalCardinalidae222014+52%1968
Northern MockingbirdMimidae192014-30%1968
American GoldfinchFringillidae182014+23%1968
Mourning DoveColumbidae172014-30%1968
American CrowCorvidae172014+16%1968
Horned LarkAlaudidae162014+33%1968
Brown-headed CowbirdIcteridae162014+421%1968
Blue GrosbeakCardinalidae162014+214%1968
Eastern BluebirdTurdidae152014+400%1971
Indigo BuntingCardinalidae142014+59%1968
Blue JayCorvidae112014+103%1968
Red-eyed VireoVireonidae102014+14%1968
Tree SwallowHirundinidae102014+91%1999
Great Crested FlycatcherTyrannidae82014-23%1968
Pine WarblerParulidae82014+100%1971
Eastern Wood-PeweeTyrannidae72014+54%1968
Song SparrowPasserellidae72014+106%1968
Carolina ChickadeeParidae62014+170%1969
KilldeerCharadriidae62014+100%1969
Fish CrowCorvidae62014+167%1979
House FinchFringillidae62014+360%1984
Ruby-throated HummingbirdTrochilidae62014+167%2001
Double-crested CormorantPhalacrocoracidae62007n/an/a
Chimney SwiftApodidae52014-77%1968
Grasshopper SparrowPasserellidae52014+12%1968
Ring-billed GullLaridae52013+133%1997
Cedar WaxwingBombycillidae52014+64%2001
Black VultureCathartidae52014+20%2009
Orchard OrioleIcteridae42010-20%1968
White-eyed VireoVireonidae42014-9%1968
Carolina WrenTroglodytidae42014+336%1968
Northern House WrenTroglodytidae42014-14%1968

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. A route is a sample, not a census.