BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Mexican Duck

AnatidaeWaterfowlAnas diazi

Mexican Duck has surged: up 143% on the route-weighted index since 1986.

+143%Since 1986TrendPercent 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 →
32RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
36Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Mexican Duck

The Mexican Duck (Anas diazi) is a North American member of the Ducks, Geese & Waterfowl (Anatidae). In this analysis it is grouped with the waterfowl.

Size
12–43.5 in long (30–110 cm) — a medium to large waterfowl (typical for the family)
Habitat
Lakes, ponds, rivers, marshes and sheltered coastal waters.
Diet
Aquatic plants, seeds and invertebrates, dabbled at the surface or dived for.
Range
Recorded on 32 Breeding Bird Survey routes across 3 states, most concentrated in the Chihuahuan Desert.
Family
Anatidae · Waterfowl

Notable Mexican Duck TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Mexican Duck. See the full index history below.

Mexican Duck Population Forecast

If the recent trend holds, Mexican Duck is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.02). A 5-year backtest shows a typical error of ±68.5%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029TrendPercent 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 →
0.01Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0295% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±68.5%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Mexican Duck is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.02). A 5-year backtest shows a typical error of ±68.5%, with 100% of held-out values landing inside the 95% band.19742029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.010.000.02
20260.010.000.02
20270.010.000.02
20280.010.000.02
20290.010.000.02

Where the Mexican Duck Is Detected

BBS routes recording Mexican Duck, sized by most recent count.

Mexican Duck Population Trend by State

Mexican Duck population trend by state.
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 →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizonainsufficient datan/a8
New Mexico-83%19938
Texas-39%199216

Mexican Duck Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Mexican Duck population trend by Bird Conservation Region.
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 →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Chihuahuan Desert+43%198818
Tamaulipan Brushlands+2%20025

Mexican Duck Conservation Status

Our route-weighted index shows it up about 142% since 1986.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.