BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Mallard In Sierra Nevada

All regionsSierra NevadaWaterfowl

Mallard in Sierra Nevada has surged: up 101% on the route-weighted index since 1973.

+101%Since 1973
27Routes In Region
50Years

Notable Signals

long arc increasecomputed index

Mallard has surged in Sierra Nevada: up 101% on the route-weighted index since 1973.

Forecast

If the recent trend holds, Mallard in Sierra Nevada is projected to rise about 78% by 2029 — from 0.84 in 2024 to a central estimate of 1.5 (95% range 0.00–3.4). A 5-year backtest shows a typical error of ±159.1%, with 100% of held-out values landing inside the 95% band.

+78%Change by 2029
1.5Projected 2029 index
0.00–3.495% range
±159.1%Backtest error
19712029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20251.40.003.3
20261.40.003.3
20271.50.003.3
20281.50.003.4
20291.50.003.4

Routes In Sierra Nevada

Routes recording Mallard in Sierra Nevada.
Last ChanceCALIFORNIA82019
PaxtonCALIFORNIA72024
Lassen ParkCALIFORNIA61989
LakeshoreCALIFORNIA32024
Tuolumne GroveCALIFORNIA22024
Hat CreekCALIFORNIA22016
Pollock PinesCALIFORNIA22012
Eagle LakeCALIFORNIA12017
DardanelleCALIFORNIA11988
Bass LakeCALIFORNIA12017
WoodfordsCALIFORNIA12003
SattleyCALIFORNIA12019
Butte MeadowCALIFORNIA11998
GeneseeCALIFORNIA12024
Higgins CornCALIFORNIA12013
DownievilleCALIFORNIA11994
RivertonCALIFORNIA12001
Chaos CraterCALIFORNIA12018
GoumazCALIFORNIA12011
Meadow ValleyCALIFORNIA12024
Little TruckeeCALIFORNIA12021
PlacervilleCALIFORNIA12024
CoultervilleCALIFORNIA12007
WawonaCALIFORNIA12002
Pine MountainCALIFORNIA12016

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.