Hummingbirds are amazing little birds capable of hovering in mid-air and flying long distances during migration. Their small size and high metabolism require them to constantly eat flower nectar and insects to survive. This need to find food sources is what drives hummingbirds to migrate. Most hummingbirds that breed in the United States and Canada migrate south for the winter, traveling to Mexico, Central America, and sometimes as far as South America. However, some hummingbirds have expanded their breeding range farther north during the summer months. This article will explore how far north different hummingbird species travel each summer and what factors influence how far north they go.
What is the northernmost point reached by hummingbirds in summer?
The hummingbird species that migrates the farthest north in summer is the Rufous Hummingbird. This feisty hummingbird breeds in forests and meadows from Alaska and Canada south to California and Colorado. The northernmost breeding population of Rufous Hummingbirds can be found along the coasts of southern Alaska. Specifically, Rufous Hummingbirds have been spotted as far north as Anchorage and Denali National Park in Alaska during summer months.
A close second for northernmost hummingbird is the Calliope Hummingbird. Calliopes breed from Washington up through British Columbia and Alberta, with some summer sightings as far north as southeastern Yukon Territory.
Other hummingbirds known to reach quite far north in summer include:
- Anna’s Hummingbird – breeds along the Pacific Coast up to southern British Columbia
- Black-chinned Hummingbird – breeds from British Columbia down across western North America
- Broad-tailed Hummingbird – breeds from Wyoming and Colorado north to Montana and Idaho
So in summary, Alaska seems to be the northernmost limit for hummingbird breeding in summer, primarily due to range expansion by the hardy Rufous Hummingbird into that region.
Why do some hummingbirds migrate farther north than others?
Not all hummingbird species migrate as far north in summer. There are several key factors that determine how far north a particular hummingbird species can expand its summer breeding grounds:
Adaptations for colder weather
Hummingbirds have high metabolisms and normally require warm environments. However, some species have evolved adaptations that allow them to withstand colder northern climates better. For example, Rufous Hummingbirds have a higher ratio of downy feathers to body size than other species, providing extra insulation. They can slow their metabolism and enter torpor overnight to conserve energy. These adaptations enable breeding farther north.
Availability of food plants
Hummingbirds depend on certain flower and tree species for nectar and insects. The ranges of their preferred food plants influence where hummingbirds can flourish during summer. For instance, the distribution of flowers like Indian paintbrush and larkspur allows Rufous Hummingbirds to breed successfully in Alaska. Other species may not have enough food sources available to survive as far north.
Competition from other hummingbirds
Some northern areas may only be inhabited by one dominant hummingbird species that can outcompete other species for food and nest sites. For example, Calliope Hummingbirds are the only species that breeds in the Yukon, likely due to exclusion of other hummingbirds. Meanwhile, farther south in British Columbia, Anna’s and Rufous Hummingbirds breed alongside Calliopes.
Nesting requirements
Hummingbirds build tiny, well-camouflaged nests in trees and shrubs. The availability of adequate nesting materials and sites may determine which hummingbird species can breed in certain northern regions. Broad-tailed Hummingbirds rely on flexible outer branches of conifers for nest placement, which allows breeding farther north across coniferous forests.
Migration distance
Some northern breeding hummingbirds, like Rufous Hummingbirds, are also extreme long-distance migrants that winter in Mexico or farther south. Other species may be unable to migrate such long distances and so cannot breed as far north. Migration distance capability varies among hummingbird species.
In summary, hummingbird species have different physical and behavioral adaptations that determine how far north they can expand their summer breeding ranges. Food availability, competitors, nesting requirements, and migration distances all play roles in setting northern range limits. Hardy species like the Rufous Hummingbird can push the northernmost breeding grounds for hummingbirds.
How many hummingbird species breed in Alaska and Canada?
Only a select number of hummingbird species have managed to adapt to breeding in Alaska and the northern regions of Canada each summer:
| Hummingbird Species | Breeding Range |
|---|---|
| Rufous Hummingbird | Breeds in southeast Alaska and north to Denali National Park; winters in Mexico |
| Calliope Hummingbird | Breeds north to southeast Yukon; winters in Mexico |
| Anna’s Hummingbird | Breeds north to southern British Columbia; many winter in Pacific Northwest instead of migrating |
| Black-chinned Hummingbird | Breeds north to southern British Columbia; winters in Mexico |
In addition, a couple of species have been spotted during summer in the northern regions but their breeding ranges do not seem to currently extend into Canada:
– Costa’s Hummingbird – Regular summer sightings in southeast Alaska; breeding range ends in British Columbia
– Broad-tailed Hummingbird – Occasional summer sightings in southern Yukon Territory; breeding range ends in Montana/Idaho
So in total, only 4 species definitely known to breed in Alaska or northern Canada, with the Rufous Hummingbird reaching the most northern point of Anchorage and Denali National Park in Alaska. The other species breed no farther north than the Yukon or British Columbia. There is still much to learn about the range limits and breeding habits of northern hummingbirds.
Do hummingbirds live year-round in Alaska and Canada?
The majority of hummingbirds that breed in Alaska and Canada migrate south in the fall to warmer climates for the winter. However, there are a couple exceptions where some hummingbird species overwinter in these northern regions:
Anna’s Hummingbird
Some Anna’s Hummingbirds have adapted to remain year-round in areas along the Pacific Coast, from southern British Columbia down into California and Arizona. This adaptation is believed to have developed within the past 40-50 years. Anna’s Hummingbirds that linger in the north supplement their diet with tree sap and insects when flowers are not available. They also reduce their metabolism and body temperature overnight. Backyard bird feeders with sugar water may also help them survive the winter in the north.
Rufous Hummingbird
A small number of Rufous Hummingbirds, mostly adult males, have been documented overwintering in southeast Alaska. These individuals take advantage of artificial feeders and heated spaces for shelter. Their ability to tolerate occasional sub-freezing nights helps enable overwintering so far north.
Calliope Hummingbird
There are a few reports of Calliope Hummingbirds overwintering in mild coastal areas of British Columbia on occasion. But this seems to be extremely rare.
So in general, overwintering by hummingbirds in Alaska and Canada is uncommon and restricted to coastal regions with ample food sources and shelter. Almost all hummingbirds that breed in the far north still migrate south for the winter. But adaptations by Anna’s and Rufous Hummingbirds allow some overwintering and year-round residency near the northern limits of hummingbird ranges. This is a relatively recent development made possible by supplemental feeding and warming climates.
How does climate change impact the northern range limits for hummingbirds?
Climate change factors like rising temperatures and earlier springs seem to be allowing northward expansion of breeding ranges for some hummingbirds in recent decades. Here are a couple key ways a warming climate impacts hummingbirds at the northern edge of their ranges:
Expanded breeding range
Warming trends allow earlier springs and longer growing seasons in the north, which provides more opportunities for nesting and raising chicks. For example, Alaska now has more consistent stretches of warm weather in May through July, allowing successful Rufous Hummingbird breeding. Some models predict continued northward expansion of breeding ranges for species like Calliope Hummingbirds under climate change.
Earlier migration timing
With earlier springs, hummingbirds are arriving sooner on their northern breeding grounds. One study found Rufous and Calliope Hummingbirds are migrating over 14 days earlier on average compared to the 1970s. This earlier arrival ensures the hummingbirds can take advantage of newly emergent food sources.
Longer residence times
Some northern hummingbirds appear to be staying later into the fall before migrating south. Warmer temperatures and food from feeders allow more hummingbirds to survive later into the season. For instance, Rufous Hummingbirds once departed Alaska in early August but now are seen there into September.
Increased overwintering
Warmer winters with fewer extended cold snaps contribute to the increasing trend of Anna’s and Rufous Hummingbirds overwintering in Alaska, British Columbia, and other northern regions instead of migrating south. Providing food and shelter in winter helps more northern hummingbirds survive.
New competition
As some species like Calliope Hummingbirds shift their breeding range farther north, they may encounter new competition with Rufous Hummingbirds already established in those northern areas. Interactions between species may change as ranges shift.
In summary, climate change allows northward range expansion for hummingbirds, supporting breeding farther north than historically recorded. This expansion will likely continue assuming warming trends continue in the future. The precise impacts on each hummingbird species and their ecological relationships remain to be fully understood over time.
Conclusion
The tenacious Rufous Hummingbird currently holds the record as the hummingbird species found farthest north in summer, breeding along the coasts of southern Alaska. Climate warming seems to be shifting suitable breeding habitat progressively north for many hummingbird species. This allows range expansion and earlier migration timing for hummingbirds across western North America. Backyard feeding and landscaping to support hummingbirds can supplement their food needs and help more hummingbirds take advantage of lengthening growing seasons in the north. With future warming, we may find Calliope Hummingbirds and other species breeding regularly even farther north in Alaska and the Yukon. For now, dedicated researchers will continue making new discoveries about how hummingbirds thrive along the northern edges of their ranges each summer.
