BBS Route · Colorado · BCR 16
Walden Bird Survey Route
A standard 50-stop Breeding Bird Survey route. 88 species recorded across 29 survey years, still active.
88Species Recorded
29Years Surveyed
1990–2024Span
5Observers
Bird Species Found on Colorado Walden
Top 40 of 88 species by most recent count. Each links to its species trend.
| History | ||||||
|---|---|---|---|---|---|---|
| Brewer's Sparrow | Passerellidae | 80 | 2024 | +27% | 1992 | |
| Vesper Sparrow | Passerellidae | 73 | 2024 | +96% | 1992 | |
| Sage Thrasher | Mimidae | 62 | 2024 | +11% | 1992 | |
| Horned Lark | Alaudidae | 58 | 2024 | -9% | 1992 | |
| Savannah Sparrow | Passerellidae | 43 | 2024 | +51% | 1992 | |
| Cliff Swallow | Hirundinidae | 24 | 2024 | +133% | 1992 | |
| Northern Rough-winged Swallow | Hirundinidae | 23 | 2018 | +850% | 1995 | |
| Wilson's Snipe | Scolopacidae | 19 | 2024 | -27% | 1992 | |
| White-crowned Sparrow | Passerellidae | 19 | 2024 | +488% | 1998 | |
| American White Pelican | Pelecanidae | 14 | 2024 | +271% | 1993 | |
| Western Meadowlark | Icteridae | 13 | 2024 | -39% | 1992 | |
| Black-billed Magpie | Corvidae | 13 | 2024 | 21× | 2006 | |
| Northern Pintail | Anatidae | 12 | 2001 | +133% | 1993 | |
| Red-winged Blackbird | Icteridae | 11 | 2024 | +20% | 1992 | |
| Yellow Warbler | Parulidae | 11 | 2024 | -30% | 1992 | |
| Common Raven | Corvidae | 10 | 2024 | +278% | 1993 | |
| Brewer's Blackbird | Icteridae | 10 | 2024 | +10% | 1992 | |
| California Gull | Laridae | 9 | 2024 | +15% | 1993 | |
| Yellow-headed Blackbird | Icteridae | 8 | 2024 | +11% | 1992 | |
| Common Merganser | Anatidae | 7 | 2023 | -42% | 2002 | |
| Green-tailed Towhee | Passerellidae | 7 | 2024 | +57% | 1992 | |
| Killdeer | Charadriidae | 6 | 2024 | -68% | 1992 | |
| American Crow | Corvidae | 6 | 2024 | -29% | 1992 | |
| American Wigeon | Anatidae | 5 | 2015 | -41% | 1992 | |
| American Robin | Turdidae | 5 | 2024 | -44% | 1992 | |
| Green-winged Teal | Anatidae | 5 | 2017 | -43% | 1999 | |
| Canada Goose | Anatidae | 5 | 2024 | +296% | 1993 | |
| American Coot | Rallidae | 5 | 2021 | +167% | 1996 | |
| Tree Swallow | Hirundinidae | 4 | 2023 | -40% | 1996 | |
| Great Blue Heron | Ardeidae | 4 | 2019 | +150% | 2001 | |
| Ring-billed Gull | Laridae | 3 | 2024 | -92% | 1990 | |
| Canvasback | Anatidae | 3 | 2019 | +0% | 2001 | |
| Swainson's Hawk | Accipitridae | 3 | 2022 | -8% | 1992 | |
| Brown-headed Cowbird | Icteridae | 3 | 2024 | -38% | 1992 | |
| Barn Swallow | Hirundinidae | 3 | 2024 | -68% | 1992 | |
| Northern House Wren | Troglodytidae | 3 | 2024 | +100% | 1992 | |
| Song Sparrow | Passerellidae | 3 | 2024 | +175% | 1999 | |
| Blue-winged Teal | Anatidae | 3 | 2003 | +50% | 2001 | |
| Marsh Wren | Troglodytidae | 3 | 2024 | +120% | 2019 | |
| Sora | Rallidae | 3 | 2017 | n/a | n/a |
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. A route is a sample, not a census.