WhenToBird

2 grosbeak species in New Jersey

When Do Grosbeaks Arrive in New Jersey?

Adult male Rose-breasted Grosbeak
Photo: Nancy Overholtz, CC BY-SA 4.0 via iNaturalist

Rose-breasted Grosbeaks and Blue Grosbeaks are the grosbeaks you are most likely to see in New Jersey. Rose-breasted Grosbeaks reach New Jersey in mid April, are common by late April, peak in the second week of May (13% of checklists), and most are gone by early October.

When to look

First arrivalsApr 15-21mid April
Common byApr 22-30late April
PeakMay 8-14the second week of May
Most gone byOct 1-7early October

Best: the second week of May. First arrivals mid April; most are gone by early October. Peak: on about 13% of New Jersey checklists.

  1. Jannot usually seen
  2. Febnot usually seen
  3. Marnot usually seen
  4. Aprcommon
  5. Maypeak season
  6. Juncommon
  7. Juluncommon
  8. Augrare
  9. Sepuncommon
  10. Octuncommon
  11. Novnot usually seen
  12. Decnot usually seen

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

Grosbeaks in New Jersey, species by species

SpeciesFirst arrivalsCommon byPeakMost gone byPeak %
Rose-breasted GrosbeakApr 15-21Apr 22-30May 8-14Oct 1-713%
Blue GrosbeakApr 22-30May 1-7Aug 1-7Sep 8-144.2%
0%5%10%15%Rose-breasted GrosbeakBlue GrosbeakJanFebMarAprMayJunJulAugSepOctNovDec
  • Rose-breasted Grosbeak
  • Blue 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 New Jersey 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 New Jersey

Best counties for Rose-breasted Grosbeak

Share of checklists at the peak
  1. Passaic CountyBest the second week of May · 1413 checklists that week, 24,933 in all32%
  2. Mercer CountyBest the second week of May · 2095 checklists that week, 56,614 in all31%
  3. Sussex CountyBest late May · 1355 checklists that week, 30,305 in all31%
  4. Hunterdon CountyBest the second week of May · 1949 checklists that week, 57,610 in all25%
  5. Somerset CountyBest the second week of May · 1936 checklists that week, 58,057 in all24%
  6. Morris CountyBest the second week of May · 2452 checklists that week, 59,212 in all23%

Common questions

When do grosbeaks arrive in New Jersey?
Rose-breasted Grosbeaks reach New Jersey in mid April, are common by late April, peak in the second week of May (13% of checklists), and most are gone by early October.
When do grosbeaks leave New Jersey?
Most Rose-breasted Grosbeaks have left New Jersey by early October, 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 grosbeaks in New Jersey?
The Rose-breasted Grosbeak is reported most often in the second week of May, on about 13% of New Jersey checklists.
Which grosbeaks are in New Jersey?
Rose-breasted Grosbeak and Blue Grosbeak are reported regularly; the Rose-breasted Grosbeak is the most common.