BirdAnalyst
BBS Route · Maryland · BCR 30

Mardela Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 103 species recorded across 49 survey years, still active.

103Species 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 →
49Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1966–2019Span
5Observers

Bird Species Found on Maryland Mardela

Top 40 of 103 species by most recent count. Each links to its species trend.

Species recorded on the Mardela 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
European StarlingSturnidae1492019+158%1968
Canada GooseAnatidae922019+91%1996
American CrowCorvidae412019+85%1968
Indigo BuntingCardinalidae402019+221%1968
Northern CardinalCardinalidae382019+46%1968
Barn SwallowHirundinidae352019+30%1968
Chipping SparrowPasserellidae262019+10%1968
Blue GrosbeakCardinalidae262019+446%1969
American RobinTurdidae202019+6%1968
Common GrackleIcteridae182019-60%1968
Carolina WrenTroglodytidae182019+460%1969
Mourning DoveColumbidae122019+50%1968
Red-winged BlackbirdIcteridae122019+263%1968
Northern MockingbirdMimidae112019-25%1968
Grasshopper SparrowPasserellidae102019+800%1971
Turkey VultureCathartidae92019+600%1968
Carolina ChickadeeParidae92019+110%1969
Red-eyed VireoVireonidae82019-54%1968
Tufted TitmouseParidae72019-17%1968
KilldeerCharadriidae72019+200%1969
Purple MartinHirundinidae62019+950%1973
Downy WoodpeckerPicidae62019+250%1974
Cedar WaxwingBombycillidae62019+175%1999
Herring GullLaridae62000n/an/a
Yellow-billed CuckooCuculidae52019-50%1968
Eastern KingbirdTyrannidae52019+300%1971
Great Crested FlycatcherTyrannidae52015+52%1968
Blue JayCorvidae52019-72%1968
Common YellowthroatParulidae52019-39%1968
Ring-billed GullLaridae52007+400%1972
Wild TurkeyPhasianidae52019+14%2001
Field SparrowPasserellidae42019-37%1968
White-eyed VireoVireonidae42019-30%1968
House SparrowPasseridae42019-97%1968
American GoldfinchFringillidae42019+243%1986
American WoodcockScolopacidae31984+200%1966
Red-bellied WoodpeckerPicidae32019+150%1968
Eastern Wood-PeweeTyrannidae32019+18%1968
MallardAnatidae32015+138%1978
Laughing GullLaridae32019+760%1978

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