Lark Sparrows reach Idaho in late April, are common by early May, peak in mid May (4.9% of checklists), and most are gone by early September.
When to look
First arrivalsApr 22-30late April
Common byMay 1-7early May
PeakMay 15-21mid May
Most gone bySep 1-7early September
Best: mid May. First arrivals late April; most are gone by early September. Peak: on about 4.9% of Idaho checklists.
Jannot usually seen
Febnot usually seen
Marnot usually seen
Apruncommon
Maypeak season
Junpeak season
Julpeak season
Augcommon
Sepuncommon
Octnot usually seen
Novnot usually seen
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 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.
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.
Blacks Creek ReservoirAda County, best mid August · 110 checklists that week, 3,935 in all28%
Busy spots report more of everything; compare the checklist counts before you drive anywhere.
Best time of day
In Idaho, the Lark Sparrow is most often listed on checklists started between 6 and 8 am (3.2% 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%
0.1%
0%
April
0.1%
0.1%
0.1%
0.9%
May
3.3%
4.5%
5.3%
4.8%
June
4.0%
3.8%
4.2%
4.2%
July
3.6%
3.2%
3.5%
3.8%
August
3.7%
2.8%
3.1%
2.8%
September
1.6%
0.9%
0.3%
0.1%
October
0.1%
0%
0%
0%
November
0%
0%
0%
0%
December
0%
0.1%
0%
0%
Neighboring states
Montana: arrives early May, 1 week later than Idaho
Utah: arrives mid April, 1 week earlier than Idaho
Oregon: arrives late April, in the same week than Idaho
Washington: arrives early May, 1 week later than Idaho
Common questions
When do Lark Sparrows arrive in Idaho?
Lark Sparrows reach Idaho in late April, are common by early May, peak in mid May (4.9% of checklists), and most are gone by early September.
When do Lark Sparrows leave Idaho?
Most Lark Sparrows have left Idaho by early September, when reports fall below half their usual rate.
When is the best time to see a Lark Sparrow in Idaho?
The Lark Sparrow is reported most often in mid May, on about 4.9% of Idaho checklists.
Where in Idaho are Lark Sparrows seen most often?
By county, Oneida County, Owyhee County, and Lincoln County have the highest peak reporting rates for the Lark Sparrow (counties with at least 200 checklists).