WhenToBird

Osprey · Pandion haliaetus

When Do Ospreys Arrive in Colorado?

Adult female Osprey
Photo: Bill Levine, CC BY 4.0 via iNaturalist

Ospreys reach Colorado in mid March, are common by late March, peak in mid April (11% of checklists), and most are gone by early October.

When to look

First arrivalsMar 15-21mid March
Common byMar 22-31late March
PeakApr 15-21mid April
Most gone byOct 1-7early October

Best: mid April. First arrivals mid March; most are gone by early October. Peak: on about 11% of Colorado checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marcommon
  4. Aprpeak season
  5. Maypeak season
  6. Juncommon
  7. Julcommon
  8. Augpeak season
  9. Sepcommon
  10. Octuncommon
  11. Novrare
  12. Decnot usually seen

Darker months: more checklists report it. Outlined: peak month.

Ospreys in Colorado, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
OspreyMar 15-21Mar 22-31Apr 15-21Oct 1-711%
0%5%10%15%OspreyJanFebMarAprMayJunJulAugSepOctNovDec
  • Osprey
Share of complete checklists reporting each species, by week (4 per month). Gaps: fewer than 10 checklists that week.

Frequency is the share of complete checklists in Colorado that listed the bird, 2016–2025. It is not a head count, and it follows where and when people go birding. How to read it.

Where in Colorado

Best counties for Osprey

Share of checklists at the peak
  1. Pueblo CountyBest the second week of April · 668 checklists that week, 26,547 in all45%
  2. La Plata CountyBest mid April · 567 checklists that week, 21,744 in all28%
  3. Mesa CountyBest late April · 1841 checklists that week, 45,553 in all26%
  4. Rio Blanco CountyBest late April · 171 checklists that week, 2,806 in all25%
  5. Grand CountyBest late August · 511 checklists that week, 11,286 in all25%
  6. Moffat CountyBest late August · 164 checklists that week, 5,700 in all24%

Common questions

When do ospreys arrive in Colorado?
Ospreys reach Colorado in mid March, are common by late March, peak in mid April (11% of checklists), and most are gone by early October.
When do ospreys leave Colorado?
Most Ospreys have left Colorado by early October, when reports fall below half their usual rate. Stragglers are still reported until late October.
When is the best time to see ospreys in Colorado?
The Osprey is reported most often in mid April, on about 11% of Colorado checklists.