BirdAnalyst
BBS Route · Iowa · BCR 22

Hudson Bird Survey Route

A standard 50-stop Breeding Bird Survey route. 101 species recorded across 34 survey years, still active.

101Species 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 →
34Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →
1967–2025Span
9Observers

Bird Species Found on Iowa Hudson

Top 40 of 101 species by most recent count. Each links to its species trend.

Species recorded on the Hudson 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
Red-winged BlackbirdIcteridae2732025+108%1969
American RobinTurdidae972025+67%1969
European StarlingSturnidae722025+37%1969
Barn SwallowHirundinidae702025+137%1969
Brown-headed CowbirdIcteridae552025+263%1969
House SparrowPasseridae522025-44%1969
American CrowCorvidae512025+66%1969
DickcisselCardinalidae412025-31%1969
Mourning DoveColumbidae372025+17%1969
Common YellowthroatParulidae342025+19%1969
Northern CardinalCardinalidae33202512×1970
Northern House WrenTroglodytidae312025+4%1969
Common GrackleIcteridae302025-74%1969
Rock PigeonColumbidae292025+23%1969
Ring-necked PheasantPhasianidae282025-45%1969
KilldeerCharadriidae252025+650%1969
Blue JayCorvidae222025+142%1969
Song SparrowPasserellidae172025-33%1969
Gray CatbirdMimidae162025+620%1969
Indigo BuntingCardinalidae142025+343%1969
Chipping SparrowPasserellidae112025+170%1969
Eastern KingbirdTyrannidae102025+89%1969
Eastern MeadowlarkIcteridae102025+227%1969
Tree SwallowHirundinidae92022+39%2007
Vesper SparrowPasserellidae82025-48%1969
Northern Rough-winged SwallowHirundinidae72013+233%1983
Black-capped ChickadeeParidae72025+425%1981
BobolinkIcteridae62022-57%1969
White-breasted NuthatchSittidae62025+125%1983
Eastern Wood-PeweeTyrannidae52025+300%1969
Red-bellied WoodpeckerPicidae52022+333%1971
Turkey VultureCathartidae52025+433%2006
Canada GooseAnatidae52025+125%1990
Yellow-billed CuckooCuculidae42021+50%1971
Downy WoodpeckerPicidae42025+50%1969
Baltimore OrioleIcteridae42025+0%1969
Field SparrowPasserellidae42025+125%1971
Brown ThrasherMimidae42025+0%1969
Cedar WaxwingBombycillidae42022+113%1981
Cooper's HawkAccipitridae42013n/an/a

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. A route is a sample, not a census.