The frenzied activity at backyard feeders each summer makes it appear hummingbirds are permanent residents. Yet come winter, they mysteriously disappear from many yards. Understanding where they go and how they survive the cold months helps us appreciate the remarkable seasonal transformations of these flying jewels.
Migration is the Primary Strategy
The main reason hummingbirds vanish from much of North America during winter is migration. Here’s an overview of their migration process:
- Most species migrate south to warmer climates with adequate flowers and insects.
- Their small size allows flying long distances rapidly with tailwinds boosting speed.
- Many species cross into Central America or Mexico, with some going as far as South America.
- Altitude impacts migration timing, with higher-elevation hummers leaving earlier.
- Age and sex impact timing too, with adult males departing before young birds and females.
- Southbound migration typically occurs between August and November depending on latitude.
Thanks to their flying skills, migration allows most hummingbirds to escape harsh winters. But some exceptions stay put.
Overwintering in Cold Climates
Not all hummingbirds migrate. A few species tough out freezing temperatures if food is available:
- Anna’s and rufous hummingbirds overwinter along the Pacific Coast where feeders are prevalent.
- Calliope hummingbirds overwinter in Mexico highlands.
- Ruby-throated and black-chinned hummingbirds may overwinter in Deep South gardens.
- Buff-bellied hummingbirds only migrate short distances within the southern US.
With sufficient feeders and flower plants, even cold-hardy hummingbirds can survive farther north all winter.
How Do They Survive Cold Weather?
Hummingbirds have adaptations to endure freezing nights and winter extremes:
- Torpor – They reduce their metabolism and body temperature to near freezing each night to conserve energy.
- Cold resistance – Their small size, fat layers, and fast metabolism all aid cold tolerance.
- Wind barriers – Cavities, trees, and shrubs provide shelter from icy winds.
- Sugary fuel – Feeders offer vital carbohydrates their fast metabolism requires.
- Migration assistance – For weaker birds, helping them bulk up pre-migration boosts winter survival odds.
While they prefer warmth, hummingbirds are built to handle short-term cold with energy reserves and rest.
Do Hummingbirds Stay in the US?
Very few hummingbird species remain year-round in the US. These are the most common overwintering species:
Species | Overwintering Range |
---|---|
Anna’s Hummingbird | Pacific Coast, Southwest US |
Rufous Hummingbird | Pacific Northwest Coast |
Allen’s Hummingbird | California Coast |
Calliope Hummingbird | Mexico Highlands |
Broad-tailed Hummingbird | Mexico, occasional Southwest US |
The small handful of species that remain rely heavily on feeders in winter. Most species migrate out entirely.
Dangers of Overwintering
Attempting to overwinter in cold climates poses serious challenges and dangers:
- Fat depletion – Hummingbirds can starve in as little as 3 hours without adequate energy reserves. Missing just one nightly torpor session is often fatal.
- Extreme cold – Temperatures below -20°F with wind can overwhelm their cold tolerance and cause frostbite.
- Ice storms – Encased ice prevents flight and access to food. Long icing periods often prove deadly.
- Predation – Torpor leaves hummingbirds vulnerable to attack. legendary alertness is diminished.
- Disease – Weakened immune systems and close feeder contact promote dangerous diseases.
The odds favor migration for most hummingbirds. But supplemented winter habitat can aid adaptable species to survive.
Best Winter Habitat Supports
Here are ways to make your yard overwintering-friendly if hummers linger:
- Maintain multiple clean, unfrozen nectar feeders 24/7. This is their sole food source.
- Hang feeders in sheltered spots like porches out of wind and ice.
- Ensure nearby tree cover so birds can rest out of the elements. Evergreen trees work best.
- Provide water trickles to prevent deadly dehydration. Change water twice daily if it freezes.
- Limit pesticide use that can accumulate in the birds and food chain.
- Place feeders within a few feet of windows so birds can see indoor perches.
- Keep feeders away from outdoor cats who pose a deadly predatory threat.
When natural food vanishes, human-provided micro-habitats become critical to get through the toughest months.
Signs Hummers Are Overwintering
Watch for these clues hummingbirds may be attempting to overwinter in your area:
- Consistent sightings into November of hardy species like Anna’s, rufous, or black-chinned
- Recurring territorial behavior and frequent feeder use into late fall
- Single birds exhibiting site loyalty for extensive periods
- Reports from neighbors of late hummingbird sightings
- Discovery of nighttime communal roosting spots
- Lethargic or inactive behavior on very cold mornings
Take note of late hummers and provide ample fuel and shelter to support their overwintering success.
Conclusion
While most vanish from wintery backyards, hummingbirds have evolved ingenious methods to persevere through seasonal scarcity. Spectacular long-distance migrations allow evasion of the harshest conditions. For tenacious species that overwinter, adaptations like torpor and fat insulation coupled with sufficient human provisions are keys to survival. Their disappearance is not permanent, as we joyfully discover when migrants reappear each spring, renewed. Our caretaking during the winter months helps ensure depleted food and deadly cold do not take an excessive toll. With some planning, we can welcome hummingbirds back again when the trees re-bloom and the days lengthen. The resourcefulness that sustains these tiny travelers through the year is a continued source of fascination and inspiration.
FAQs
Where do hummingbirds go in winter?
Most migrate south to warmer climates in Mexico, Central America, and South America. However, some species overwinter along the Pacific Coast or Deep South where feeders and flowers allow survival.
How do hummingbirds survive cold winters?
Strategies like nightly torpor, fat insulation, wind barriers, and ample feeders allow a few species to endure freezing temperatures in northern climes. Most migrate to avoid harsh conditions.
What hummingbirds stay in the US for winter?
Anna’s, rufous, Allen’s, calliope, broad-tailed, black-chinned, buff-bellied, and ruby-throated hummingbirds occasionally overwinter in sheltered southern regions if feeders are available.
Should I take down hummingbird feeders in winter?
Leave feeders up through winter in case overwintering birds remain. Monitor for consistent activity indicating your yard is supporting year-round hummers.
How can I make my yard winter-friendly for hummingbirds?
Provide sheltered feeders that don’t freeze, nearby trees for roosting, clean unfrozen water, elimination of pesticides, and monitoring for lingering birds.
What are signs hummingbirds are overwintering?
Territorial behavior in late fall, lethargy on cold days, site loyalty of individuals, reports of late sightings in your area, and discovery of nighttime communal roosts all indicate overwintering.
Do hummingbirds migrate every year?
Yes, migration is an annual pattern. Inadequate food in most regions makes winter survival impossible without migrating south or human support such as feeders.
How far south do ruby-throated hummingbirds migrate?
While a few may overwinter in the south, most ruby-throats migrate through Mexico into Central America for winter, travelling over 1,000 miles from their breeding grounds.