Wisconsin's hummingbird season runs from mid-May through mid-September almost everywhere in the state — Ruby-throated Hummingbird is the only species that breeds here, and it arrives on nearly the same week statewide, from the Apostle Islands to the Illinois border. The real variation shows up on the way out: most of Wisconsin empties out by mid-September, but Dane County sees a genuine second act, with Rufous Hummingbird — a species that breeds far to the west — showing up reliably enough there each fall to keep feeders busy into November.

The short answer: Ruby-throated arrives statewide by mid-May and is gone from most of the state by mid-September. Rufous is real, annual, and concentrated overwhelmingly in Dane County, where it keeps a genuine presence going into early November — the one real exception to the rest of the state's calendar.

Wisconsin's Hummingbird Season at a Glance

Before the region-by-region detail below, here's the whole season in one picture.

How often Ruby-throated Hummingbird — Wisconsin's only confirmed breeder — shows up on eBird checklists, week by week, statewide, 2016–2025. Seven more species have been documented in Wisconsin, but only one, Rufous Hummingbird, has a real seasonal pattern worth charting — see its own chart just below. The rest are true rarities, most with just one or a handful of accepted records and no reliable eBird trail behind them. Full details in the Sources section below.

That chart tells you who's biggest, but it can hide who's smallest — Ruby-throated's huge peak visually flattens a real species like Rufous Hummingbird into what looks like nothing next to it, even though Rufous has a genuine season of its own. Here's the same data again, but scaled to Rufous's own peak instead of Ruby-throated's, so a species you'd never spot on the chart above still shows its actual shape below.

Rufous Hummingbird alone, scaled to its own real range — the only Wisconsin species outside Ruby-throated with a genuine, recurring multi-week pattern. Source: same eBird pull as above.

Arrival and departure windows by region, based on eBird checklist data (Cornell Lab of Ornithology), 2016–2025.

January, February, March & April: The Quiet Season

Genuinely nothing to report. Statewide and in all five tracked counties, both Ruby-throated and Rufous sit at zero real signal this entire stretch — Ruby-throated hasn't arrived yet, and Rufous's fall presence has already faded out well before winter sets in (more on that in November and December below). If you're seeing a "hummingbird" at a Wisconsin feeder in these four months, it's worth a second look and a photo — real winter records exist for the state, but they're single-digit rarities, not something to expect in your own yard.

What to do: Nothing hummingbird-specific. If you keep a feeder up anyway, there's no real data reason to.

Set up before the wave arrives, not after. Wisconsin's hummingbirds show up within days of each other almost statewide, so there's a narrow window to have everything ready. Putting a swing out now gives returning birds a comfortable place to rest and claim as their own right from the start of the season. Shop swings →

May: The Season Begins

Wisconsin's real arrival, and the surprise in the data is how synchronized it is. Every one of the five tracked counties — from Bayfield on Lake Superior to Milwaukee on the Illinois line — reaches reliable Ruby-throated activity the same week, mid-May, give or take a few days. That's not what you'd expect from a state that spans nearly five degrees of latitude, and it's worth saying plainly: unlike many states, Wisconsin doesn't have a real north-to-south arrival gap.

What to do: Feeders up by early May, ahead of the wave rather than after it.

June: The Nesting Lull

Statewide frequency actually dips in June — down to roughly 13–14% of checklists after touching nearly 18% in mid-May — before climbing again through the summer. That's not birds leaving; it's nesting settling in. Incubating and brooding females spend more time on the nest and less time visibly working a feeder, which shows up in the data as a real, temporary lull rather than a departure.

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July: Building Toward the Peak

Numbers climb steadily out of June's lull, and Wisconsin's summer heat brings the usual pest pressure right alongside the birds — ants and bees competing for the same nectar hummingbirds need.

Keep pests off without pesticides — hummingbirds rely on small insects for protein, so spraying near a feeder can cost them a food source, not just protect one. AspenPerch®'s built-in ant moat blocks ants with a water barrier, and Hummguard™ Nectar Tips keep bees and wasps out without changing anything for the birds. Shop AspenPerch® →  |  Shop Hummguard™ →

August: The Season's Peak

Wisconsin's single busiest stretch of the year: Ruby-throated hits its statewide peak of 30% of checklists in the first week of August. This is also the real pre-migration fueling window — birds are building fat reserves for the trip south, and feeder demand is at its highest of the year right before the sharp September decline.

This is the month to be generous, not economical. Birds fueling for a long flight need feeders topped up more often — the large 2lb Nectarlyte® powder or the Nectarade® liquid concentrate keeps you from running out mid-surge. Shop Nectarlyte® 2lb →  |  Shop Nectarade® Concentrate →

September: The Big Departure

This is when most of Wisconsin's hummingbirds leave. Bayfield, La Crosse, and Portage all drop below reliable activity by mid-September; Milwaukee's birds leave a little later, into late September. Statewide, numbers fall from August's 30% peak to near zero within about a month — the fastest single stretch of change all year.

What to do: Take your feeder down about two weeks after your last sighting, not by a fixed date — that accounts for your own yard and this year's weather better than any calendar can. If you're in Dane County, keep at least one feeder up regardless: it's the one region that doesn't follow the rest of the state's September exit.

October: Rufous Hummingbird's Real Season

Ruby-throated is gone from essentially the entire state by now. But October is when Rufous Hummingbird's real presence builds — statewide frequency climbs through the month to its own peak of 0.48% in early October, and that signal is concentrated overwhelmingly in Dane County. It's real and annual, not a fluke sighting: a genuine, recurring fall pattern, just a much smaller one than Ruby-throated's summer season.

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November & December: The Last Stragglers

Dane County's real story continues into November — Rufous stays reliably present there into early November, a genuine extension backed by real checklist volume, not just a stray individual or two. By December, though, even Dane's birds have left for good. Unlike some states farther south or nearer the coast, Wisconsin's Rufous doesn't overwinter here; it builds through the fall and then leaves completely rather than settling in for the cold months. By the time December arrives, the whole state — Dane included — has returned to the same quiet stretch that opens this calendar.

What to do: If you're in Dane County, there's real reason to keep a feeder up through early November. Everywhere else, the season's effectively over by the time November starts.

The Year at a Glance

Frequently Asked Questions

When do hummingbirds arrive in Wisconsin?

Mid-May, and unusually evenly across the state — Bayfield in the far north and Milwaukee in the southeast both reach reliable activity the same week, which isn't the case in most states this size.

When do hummingbirds leave Wisconsin?

Most of the state's hummingbirds leave by mid-to-late September. The one real exception is Dane County, where Rufous Hummingbird keeps a genuine presence going into early November.

When do hummingbirds leave northern Wisconsin?

Earlier than the rest of the state, not later. Bayfield County — Wisconsin's real far-north region, on Lake Superior — is the first place in the state where hummingbirds leave, by mid-September, about a week to two weeks ahead of Milwaukee in the southeast.

Are there hummingbirds in Wisconsin in the winter?

No, not reliably. By December the entire state, including Dane County's Rufous population, has gone quiet. A hummingbird at a Wisconsin feeder in January or February would be a genuine rarity worth documenting, not something to expect.

Why does my Dane County feeder still have hummingbirds in October?

That's almost certainly Rufous Hummingbird, not a late Ruby-throated. Dane County carries the great majority of Wisconsin's real Rufous signal, and its real season — building through September, peaking in early October — runs a full month past when Ruby-throated has left the rest of the state.

Why We Built This Calendar

Pop's Birding has been helping hummingbird lovers for three generations. One of the questions our customers ask most often is "When do hummingbirds arrive and leave my state?" — we built this calendar to give a direct, sourced answer, not a generic one. Most timing advice online gives a single date for an entire state, and for Wisconsin the surprise isn't where that falls short on arrival — arrival really is close to a single date here — it's that departure genuinely isn't. Dane County keeps hummingbirds around a full month longer than the rest of the state, and a single "gone by September" answer would be wrong for that one real, checkable region.

How We Built This Calendar

We pulled eBird bar chart data (Cornell Lab of Ornithology) for Wisconsin statewide and for five counties — Bayfield, Portage, La Crosse, Dane, and Milwaukee — covering 2016 through 2025, chosen to represent Wisconsin's genuinely different geography rather than just its most populous places. "Reliably present," used throughout this calendar, is the first week a region's reporting rate reaches 25% of that region's own seasonal peak for that species — we use each region's own peak, not a statewide one, since a thinly-birded county and a heavily-birded one don't share a baseline. Before trusting any region's number, we checked the actual checklist count behind it, not just the percentage: two candidate findings — a possible Rufous season-extension in both Portage and Milwaukee counties — were tested this way and rejected, backed by only 1 and 4 effective checklists respectively, too thin to trust. Dane County's real extension, by contrast, is backed by 30 effective checklists at its latest reliable week — a genuine signal, not a fluke.

The real finding this build turned up ran opposite to what we expected going in: Wisconsin's north-south spread suggested a real arrival gap was likely, the way it shows up in most states this size. It isn't there — every tracked region, Bayfield included, reaches reliable Ruby-throated activity the same week in mid-May. The genuine regional story is entirely on the departure side, and it's driven by a different species than the one that dominates the rest of the calendar: Rufous Hummingbird, not Ruby-throated, and concentrated almost entirely in one county. A second, smaller finding: unlike some more southerly states, Wisconsin's Rufous population doesn't overwinter — it builds through the fall and departs completely, rather than settling in through the cold months.

The two charts above exist for the same reason as everywhere else on this site: a single chart showing both species on a shared scale would make Rufous's real, genuine season invisible next to Ruby-throated's much larger peak — not because anything's hidden, just a difference in scale. The second chart, normalized to Rufous's own peak, exists so that real pattern doesn't disappear from the picture.

The county-level comparison, the arrival-synchronization finding, and the Dane County departure extension are original analysis built from the raw eBird data — not a rewrite of eBird's own bar charts, which report state and county numbers separately and don't compare arrival timing against departure timing the way this calendar does.

Sources

• eBird bar chart data, Cornell Lab of Ornithology — Wisconsin statewide plus Bayfield, Portage, La Crosse, Dane, and Milwaukee counties, 2016–2025. Source for all arrival, departure, and peak figures.
• Wisconsin Society for Ornithology, Official Checklist of Wisconsin Birds (updated 23 March 2025). Source for Wisconsin's full 8-species list and status codes for every rare visitor.
• Wisconsin Society for Ornithology, Rare Bird Records. Source for individual rare-species record counts and dates.