Pectoral Sandpipers arrive in Montana in the second week of August, peak in mid September (2.5% of checklists), and most are gone by the second week of October.
When to look
First arrivalsAug 8-14the second week of August
Common byAug 8-14the second week of August
PeakSep 15-21mid September
Most gone byOct 8-14the second week of October
Best: mid September. First arrivals the second week of August; most are gone by the second week of October. Peak: on about 2.5% of Montana checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Aprnot usually seen
Mayrare
Junnot usually seen
Juluncommon
Augpeak season
Seppeak season
Octpeak season
Novrare
Decnot usually seen
Darker months: more checklists report it. Outlined: peak month.
Share of complete checklists reporting it, by week (4 per month). Grey bars: fewer than 10 checklists, not counted.
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.
JanFebMarAprMayJunJulAugSepOctNovDec
today
0%few checklistsno data
Each county is shaded by the share of complete checklists there that listed the bird, blended with the weeks either side. Darker is more often. It follows where people watch birds, not how many birds there are. How to read it.
Willow Creek ReservoirMadison County, best early October · 21 checklists that week, 510 in all45%
Cottonwood ReservoirPark County, best late September · 20 checklists that week, 638 in all39%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Montana, the Pectoral Sandpiper is most often listed on checklists started between 8 and 10 am (0.6% of those checklists).
Share of checklists started in each local hour that reported it. It reflects when people go birding as well as when birds are active. Grey hours have too few checklists (under 2% of the state’s, or under 200) to judge.Week-by-week table
Month
Days 1-7
8-14
15-21
22-end
January
0%
0%
0%
0%
February
0%
0%
0%
0%
March
0%
0%
0%
0%
April
0%
0.1%
0.1%
0.1%
May
0.1%
0.2%
0.1%
0.1%
June
0.1%
0.1%
0.1%
0%
July
0.1%
0.2%
0.4%
0.4%
August
0.7%
1.4%
2.0%
2.4%
September
2.5%
2.3%
2.1%
2.9%
October
1.5%
1.1%
1.3%
0.5%
November
0.2%
0.1%
0%
0%
December
0%
0%
0%
0%
Neighboring states
Idaho: arrives mid August, 1 week later than Montana
Wyoming: arrives mid August, 1 week later than Montana
Utah: arrives late August, 2 weeks later than Montana
Washington: arrives mid August, 1 week later than Montana
Common questions
When do Pectoral Sandpipers arrive in Montana?
Pectoral Sandpipers arrive in Montana in the second week of August, peak in mid September (2.5% of checklists), and most are gone by the second week of October.
When do Pectoral Sandpipers leave Montana?
Most Pectoral Sandpipers have left Montana by the second week of October, when reports fall below half their usual rate.
When is the best time to see a Pectoral Sandpiper in Montana?
The Pectoral Sandpiper is reported most often in mid September, on about 2.5% of Montana checklists.
Where in Montana are Pectoral Sandpipers seen most often?
By county, Broadwater County, Fallon County, and Musselshell County have the highest peak reporting rates for the Pectoral Sandpiper (counties with at least 200 checklists).