WhenToBird

2 grosbeak species in Idaho

When Do Grosbeaks Arrive in Idaho?

Adult Black-headed Grosbeak
Photo: Dan Vickers, CC BY 4.0 via iNaturalist

Black-headed Grosbeaks and Evening Grosbeaks are the grosbeaks you are most likely to see in Idaho. Black-headed Grosbeaks reach Idaho in early May, are common by the second week of May, peak in late May (21% of checklists), and most are gone by the second week of August.

When to look

First arrivalsMay 1-7early May
Common byMay 8-14the second week of May
PeakMay 22-31late May
Most gone byAug 8-14the second week of August

Best: late May. First arrivals early May; most are gone by the second week of August. Peak: on about 21% of Idaho checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprrare
  5. Maypeak season
  6. Junpeak season
  7. Julcommon
  8. Augcommon
  9. Seprare
  10. Octnot usually seen
  11. Novnot usually seen
  12. Decnot usually seen

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

Grosbeaks in Idaho, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Black-headed GrosbeakMay 1-7May 8-14May 22-31Aug 8-1421%
Evening GrosbeakJan 1-7Mar 22-31May 15-21Nov 15-215.9%
0%10%20%30%Black-headed GrosbeakEvening GrosbeakJanFebMarAprMayJunJulAugSepOctNovDec
  • Black-headed Grosbeak
  • Evening Grosbeak
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 Idaho 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 Idaho

Best counties for Black-headed Grosbeak

Share of checklists at the peak
  1. Adams CountyBest late June · 193 checklists that week, 5,826 in all68%
  2. Nez Perce CountyBest mid June · 154 checklists that week, 10,708 in all53%
  3. Benewah CountyBest the second week of June · 96 checklists that week, 2,541 in all42%
  4. Boise CountyBest the second week of June · 292 checklists that week, 6,761 in all37%
  5. Teton CountyBest the second week of June · 142 checklists that week, 6,406 in all37%
  6. Madison CountyBest early June · 103 checklists that week, 3,887 in all36%

Common questions

When do grosbeaks arrive in Idaho?
Black-headed Grosbeaks reach Idaho in early May, are common by the second week of May, peak in late May (21% of checklists), and most are gone by the second week of August.
When do grosbeaks leave Idaho?
Most Black-headed Grosbeaks have left Idaho by the second week of August, when reports fall below half their usual rate. Stragglers are still reported until early September.
When is the best time to see grosbeaks in Idaho?
The Black-headed Grosbeak is reported most often in late May, on about 21% of Idaho checklists.
Which grosbeaks are in Idaho?
Black-headed Grosbeak and Evening Grosbeak are reported regularly; the Black-headed Grosbeak is the most common.