WhenToBird

Osprey · Pandion haliaetus

When Do Ospreys Arrive in Montana?

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

Ospreys reach Montana in late March, are common by the second week of April, peak in late April (15% of checklists), and most are gone by mid September.

When to look

First arrivalsMar 22-31late March
Common byApr 8-14the second week of April
PeakApr 22-30late April
Most gone bySep 15-21mid September

Best: late April. First arrivals late March; most are gone by mid September. Peak: on about 15% of Montana checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marrare
  4. Aprpeak season
  5. Maypeak season
  6. Juncommon
  7. Julpeak season
  8. Augpeak season
  9. Seppeak season
  10. Octuncommon
  11. Novnot usually seen
  12. Decnot usually seen

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

Ospreys in Montana, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
OspreyMar 22-31Apr 8-14Apr 22-30Sep 15-2115%
0%5%10%15%20%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 Montana 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 Montana

Best counties for Osprey

Share of checklists at the peak
  1. Ravalli CountyBest late April · 583 checklists that week, 16,671 in all38%
  2. Madison CountyBest late April · 291 checklists that week, 7,008 in all34%
  3. Lincoln CountyBest late July · 214 checklists that week, 5,543 in all32%
  4. Sanders CountyBest late April · 114 checklists that week, 3,767 in all30%
  5. Mineral CountyBest late August · 63 checklists that week, 2,163 in all28%
  6. Powell CountyBest mid April · 150 checklists that week, 5,305 in all26%

Common questions

When do ospreys arrive in Montana?
Ospreys reach Montana in late March, are common by the second week of April, peak in late April (15% of checklists), and most are gone by mid September.
When do ospreys leave Montana?
Most Ospreys have left Montana by mid September, when reports fall below half their usual rate. Stragglers are still reported until the second week of October.
When is the best time to see ospreys in Montana?
The Osprey is reported most often in late April, on about 15% of Montana checklists.