Hummingbirds are a beloved sign of spring and summer in Wisconsin, brightening gardens and feeders with their tiny, jewel-like presence. However, by late summer and early fall, it’s common for hummingbird numbers to start dwindling as these tiny birds begin their migration south to their wintering grounds.
When do hummingbirds migrate from Wisconsin?
Most hummingbirds start leaving Wisconsin by mid-August. The exact timing depends on the species:
- Ruby-throated hummingbirds are usually the first to leave, starting their southward migration as early as late July.
- Rufous hummingbirds depart later, often sticking around until September.
- Calliope hummingbirds are some of the last to leave, and may linger into early October in northern parts of the state.
Weather conditions can also impact migration timing. Colder temperatures and fewer food sources prompt earlier fall departures. In warmer autumns, some hummingbirds may stay a bit longer in Wisconsin before migrating.
What triggers hummingbird migration?
Several factors spur hummingbirds to migrate in the late summer and fall:
- Declining food sources – Flowers begin fading and insect numbers drop as winter approaches. This makes it harder for hummingbirds to meet their high metabolism’s demands.
- Changing daylight – Shortening days provide a cue to start migrating south.
- Cooling temperatures – Hummingbirds are sensitive to cold due to their tiny size and high body temperature. Leaving for warmer climes helps them survive.
- Breeding urges – For adult males and non-breeding females, migration is driven by the urge to reach southern breeding grounds in preparation for the next reproductive season.
Instinct drives juvenile birds on their very first migration, even though they have never made the trip before. Days growing incrementally shorter provide the trigger to begin the southerly journey.
Where do the hummingbirds that summer in Wisconsin migrate to?
The Ruby-throated hummingbird winters primarily in Mexico and Central America, with some reaching Panama and Florida. Rufous and Calliope hummingbirds migrate to the southern U.S. and Mexico for the winter months.
What are the migration routes for Wisconsin’s hummingbirds?
Banding and tracking studies show that hummingbirds follow certain flyways on their fall and spring migrations:
Ruby-throated
- Most follow an eastern route across the Great Lakes to the Gulf Coast.
- Some migrate across the Appalachian Mountains towards the southeastern U.S. coast.
Rufous
- Take a northwestern path across the Great Plains towards the southwestern U.S. and Mexico.
Calliope
- Funnel through mountain passes, traveling south along the Pacific Coast.
- Others follow a central route towards Mexico’s highlands.
No matter the path, migrating hummingbirds make an incredible nonstop flight across the Gulf of Mexico to reach their winter homes in a single trip. For Ruby-throated hummingbirds, this can mean flying up to 500 miles continuously over open water.
How long does the hummingbird migration take?
On average, a hummingbird’s fall or spring migration takes:
- Ruby-throated: 30 to 45 days
- Rufous: About 30 days
- Calliope: 25 to 35 days
However, migration duration can vary depending on weather, food availability along the route, and other factors. The little birds travel remarkably fast for their size, averaging 25-30 miles per hour but capable of hitting up to 60 mph in ideal conditions.
| Species | Average Migration Speed | Distance Traveled Per Day |
|---|---|---|
| Ruby-throated | 25-30 mph | 300 miles |
| Rufous | 20-25 mph | 200 miles |
| Calliope | 20-27 mph | 225 miles |
This allows them to cover large distances remarkably fast for such tiny fliers. Still, the southward migration is an arduous feat involving huge energy expenditure for hummingbirds.
Do any hummingbirds stay in Wisconsin year-round?
In most years, Wisconsin winters are too harsh for hummingbirds to survive. However, a few very rare cases of overwintering hummingbirds have been documented, mainly Rufous and Calliope hummingbirds attempting to stay into December or January rather than migrating.
Without sufficient food from flowers and insects, these birds are unlikely to survive the entire winter. They may linger if they find an active feeder providing high energy syrup. But freezing nights, snow, and extended bad weather pose life-threatening dangers.
Attempting to overwinter is an unusual behavior for hummingbirds in Wisconsin. Most migrate south by late fall at the latest to find adequate food sources and escape freezing temperatures.
When do hummingbirds return to Wisconsin in spring?
The first wave of migrant hummingbirds starts arriving back in Wisconsin in early to mid April as spring bloom begins. Migration timing is dependent on species:
- Ruby-throated hummingbirds are typically the first arrivals, showing up starting in early April.
- Rufous hummingbirds return later in April and early May.
- Calliope hummingbirds arrive last from mid-May through June.
As with fall migration, weather patterns and food availability play a role in precise spring migration timing. Warmer weather and plentiful flowers may draw hummingbirds back sooner to take advantage of resources.
Do the same individual hummingbirds return each year?
Remarkably, research indicates adult hummingbirds often return to the exact same breeding grounds every spring. Scientists have banded and tracked Ruby-throated hummingbirds returning to prior Wisconsin nesting sites from over 1,500 miles away in Mexico multiple springs in a row.
Strong homing abilities allow the hummingbirds to navigate back hundreds or thousands of miles to favored breeding habitats. Adults may seek the same food sources, perches, and even partners from previous summers. This site loyalty improves breeding success.
Signs that hummingbirds have returned to an area
How can you tell if hummingbirds are back in your neighborhood? Watch for these signs of spring arrivals in Wisconsin:
- Males scouting territories – Adult males reach breeding areas first and scout out feeding areas to claim as territories.
- Females and immatures – About 1-2 weeks after males arrive, watch for females and younger birds.
- Increased activity at feeders – More hummingbirds may start visiting nectar feeders in the area.
- Fighting around feeders – Competing males battle for prime feeder access as they establish territories.
- Courting displays – Males perform dramatic dive displays to court females.
- Nest building – Females gathering spider silk and lichen to build tiny nests signal spring breeding activity.
- Plant flowering – Arrivals coincide with blooms of hummingbird-favored plants like columbine, bee balm, and trumpet vine.
Observing these behaviors are a sure sign hummingbird populations are returning from their southern wintering grounds to breed in Wisconsin.
Conclusion
While it may seem that Wisconsin’s hummingbirds disappear each fall, these tiny birds are simply migrating south to find the food and warmth needed to survive winter. Their return each spring brings excitement and anticipation of the active summer season ahead as local hummingbird populations flourish. Watching arrivals in spring and departures in fall allows us to enjoy the full lifecycle of these charismatic birds.
