Species · North Dakota · BBS 2025 Release · 1966–2024
Thick-billed Longspur Population Trend in North Dakota
Thick-billed Longspur in North Dakota has collapsed: down 82% on the route-weighted index since 1971.
-82%Since 1971
3Routes In State
21Years
Notable Thick-billed Longspur Trends in North Dakota
long arc declinecomputed index
Thick-billed Longspur has collapsed in North Dakota: down 82% on the route-weighted index since 1971.
Thick-billed Longspur Population Forecast in North Dakota
If the recent trend holds, Thick-billed Longspur in North Dakota is projected to fall about 100% by 2002 — from 0.07 in 1997 to a central estimate of 0.00 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±86.1%, with 100% of held-out values landing inside the 95% band.
-100%Change by 2002
0.00Projected 2002 index
0.00–0.1395% range
±86.1%Backtest error
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 1998 | 0.00 | 0.00 | 0.13 |
| 1999 | 0.00 | 0.00 | 0.13 |
| 2000 | 0.00 | 0.00 | 0.13 |
| 2001 | 0.00 | 0.00 | 0.13 |
| 2002 | 0.00 | 0.00 | 0.13 |
Thick-billed Longspur Survey Routes in North Dakota
Thick-billed Longspur Population Trend in Other States
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.