The ruby throated hummingbird (Archilochus colubris) is one of the most common and widely recognized hummingbird species in North America. Ruby throated hummingbirds breed in forests and woodlands across much of eastern North America during the spring and summer months. The ruby throated hummingbird breeds in a range extending from southern Canada south throughout the eastern United States and along the Gulf Coast. Some key questions about where ruby throated hummingbirds breed include:
- What is the breeding range of the ruby throated hummingbird?
- What types of habitats do ruby throated hummingbirds nest and breed in?
- How far north do ruby throated hummingbirds breed?
- How far west do ruby throated hummingbirds breed?
- Do ruby throated hummingbirds breed in the western United States?
Breeding Range
The ruby throated hummingbird breeding range extends from southern Canada south throughout the eastern United States. According to the Cornell Lab of Ornithology, the ruby throated hummingbird breeding range includes:
- In Canada: Southern Ontario, southern Quebec, New Brunswick, Nova Scotia and Prince Edward Island
- In the United States: East of the 100th meridian, from the Gulf of Mexico north up the Atlantic seaboard to Maine and the Canadian Maritime provinces
This range stretches approximately 3,000 miles from north to south during the breeding season. The ruby throated hummingbird is found breeding in most states east of the Mississippi River and some to the west as well including Minnesota, Iowa, Missouri, Arkansas and Louisiana.
Western Limit
The western limit of the ruby throated hummingbird breeding range is approximately the 100th meridian which runs through the central plains states. This line roughly follows the eastern borders of North Dakota, South Dakota, Nebraska, Kansas, Oklahoma and Texas.
West of this 100th meridian line, ruby throated hummingbirds are rare during the breeding season. Sightings west of this line likely represent migrating individuals rather than breeding birds.
Northern Limit
In Canada, ruby throated hummingbirds breed as far north as southern Ontario, southern Quebec, New Brunswick, Nova Scotia and Prince Edward Island.
Within this northern range, breeding ruby throats are mainly restricted to the southern portions of these provinces, approximately south of the 45th parallel north. Sightings further north, such as in northern Ontario, are likely migrating individuals.
Southern Limit
On the southern end of their breeding range, ruby throated hummingbirds nest as far south as the Gulf Coast in states like Louisiana, Mississippi, Alabama and Florida. The southern limit of their breeding range reaches south to the Gulf of Mexico coastline.
Throughout this southern range, ruby throated hummingbirds can be found breeding in appropriate habitat anywhere from the coastline inland to the Appalachian Mountains region.
Breeding Habitats
Within their broad eastern breeding range, ruby throated hummingbirds nest in a variety of forest and woodland habitats. Their preferred breeding habitats include:
- Deciduous forests
- Mixed forests
- Pine forests
- Forest edges and openings
- Parks and gardens
- Orchards
Ruby throated hummingbirds often avoid breeding in dense, dark forest interiors. They prefer habitat edges, openings, and patchy forests that allow sunlight to reach flowering plants. This provides nectar sources close to nest sites.
Deciduous Forests
In northern areas, ruby throated hummingbirds commonly nest in deciduous broadleaf forests dominated by trees like oak, maple, birch, beech, hickory, and poplar. Open understory with flowers provides food.
Mixed and Pine Forests
Further south, ruby throats nest in mixed pine-hardwood forests as well as pure pine forests. Nesting occurs in stands of pine trees or at habitat edges where pines transition to hardwoods.
Forest Openings
Forest clearings and edges with wildflowers are prime ruby throated hummingbird nesting areas. These openings allow sunlight to reach nectar sources near nest sites.
Parks and Gardens
Ruby throats readily nest in parks, backyard gardens, and other urban green spaces with flowers providing they have adjacent forest areas for nest sites.
Orchards
Flowering orchards adjacent to forests are another preferred breeding habitat, especially in the early spring before leaf-out.
Nest Sites
Within their breeding habitats, female ruby throated hummingbirds choose the specific nest site location. Favored features include:
- On a downward sloping tree limb
- Over water or a stream
- 10-20 feet above ground
- Often near thorns or poison ivy for protection
- Deciduous trees more often than conifers
Nests are small, lichen-covered cups typically built where two branches meet emerging from the main tree trunk. This provides structural support and protection.
Tree Selection
Ruby throats use a variety of deciduous and coniferous trees for nest placement, though deciduous trees are used most often. Favored nest trees include:
- Maple
- Birch
- Elm
- Oak
- Beech
- Pine
- Fir
- Spruce
Nest Height
Ruby throated hummingbird nests are typically 10-20 feet above the ground. Lower heights from 5-10 feet up may be used where higher options are unavailable. Higher nests 20-30 feet up are occasionally spotted as well.
Over Water
Nest sites directly over creeks, streams, rivers or ponds are favored where available. The water provides insect food and also makes nest access difficult for predators.
Courtship and Mating
Ruby throated hummingbirds have an elaborate mating ritual to start the breeding process after migration:
- Males arrive first and establish breeding territories
- Males perform aerial courtship displays to attract females
- Females arrive approximately 1 week after males
- Females mate with the dominant male in the territory
- No long term pair bonds form, females move between males
The male courtship display is an aerial show where he flies in loops up to 130 feet in the air before diving sharply back towards the female. A range of chirps and buzzing sounds accompany the display.
Male Arrival
Male ruby throats arrive back on the breeding grounds first, usually in late April or early May depending on latitude. The earlier arriving males have the advantage in establishing the best breeding territories.
Territorial Defense
Males defend breeding territories approximately 1 quarter acre in size through aggressive displays towards other males. These territories provide feeding areas and potential mates for the season.
Female Arrival
Females return approximately one week after males, in early to mid May. They quickly mate with the dominant territorial male. This short time frame keeps the overall breeding season brief.
Short Term Mating
Ruby throats do not form long term pair bonds. Females will mate with multiple territorial males through the breeding season. Males try to mate with every female that passes through his territory.
Nest Building
Nest building is done solely by the female ruby throated hummingbird over approximately 10 days:
- Collects down, plant fibers and lichens for materials
- Binds materials together with spider silk
- Forms a small 1.5 inch wide cup
- Attaches to branch with spider silk
- Decorates with lichens for camouflage
The tiny, well-camouflaged nests are difficult to spot in the habitats ruby throats prefer. Nests are often built 10-20 feet up surrounded by concealing leaves and branches.
Cup Shaped
Ruby throated hummingbird nests are tiny, cup shaped structures only about 1.5 inches wide. The small but sturdy cups provide a secure place for eggs and chicks.
Materials
The nest cup is constructed from soft plant down, bud scales, bark fibers, stems and other plant material. Spider silk binds it all together and attaches the nest to branches.
Camouflage
Lichens, moss and algae are added to the outside surface to effectively camouflage the nest against branches and foliage.
Reuse
Females may repair and reuse nests from previous years if they are still intact. More often they build a new nest each breeding season.
Egg Laying and Incubation
Once nest building is complete, the female ruby throated hummingbird lays and incubates the eggs:
- Lays 1-3 tiny white eggs
- Lays one egg per day over consecutive days
- Eggs are approximately 0.5 inches long
- Incubates eggs for 11-14 days
- Sits tight on nest, leaves only briefly
The eggs are only about the size of a pea. The female attentively incubates the eggs, providing heat essential for development.
Clutch Size
Ruby throated hummingbird clutches are small, with 1-3 eggs being typical. Two eggs is the most common clutch size. Large clutches over 3 eggs may indicate more than one female using the nest.
Egg Size
The tiny white eggs measure only about 0.5 inches long and not much wider than a pencil eraser. This small size contributes to the difficulty in finding ruby throated hummingbird nests.
Incubation Period
The female incubates the eggs for 11-14 days until hatching. This is a relatively long incubation period compared to other similarly sized birds. The extra time contributes to the hummingbirds’ precocial development.
Constant Incubation
The female develops a bare brood patch to transfer warmth to the eggs. She sits tight on the nest constantly, leaving only very briefly to drink nectar and catch insects. Continuous incubation is vital for hatching success.
Raising Nestlings
Once the eggs hatch, intensive care of the hatchlings by the female begins:
- Hatchlings are tiny, weighing 0.1 – 0.2 ounces
- Nestlings fed small insects and nectar by female
- Feedings occur every 10-20 minutes from dawn to dusk
- Nestlings fly from nest at 18-28 days old
The high energy food enables remarkable growth of the tiny hatchlings in preparation for surviving on their own.
Hatchling Size
Newly hatched ruby throats weigh just 0.1 – 0.2 ounces, about the weight of a penny. Their eyes are sealed shut and they have just a hint of fuzzy down. But they grow incredibly fast.
Frequent Feedings
The female feeds the hatchlings every 10-20 minutes from dawn through dusk. She catches tiny insects and nectar to fuel their rapid development.
Diverse Diet
The hatchling diet includes small insects like fruit flies, gnats, aphids and spiders. The female also regurgitates nectar into the hatchling’s mouths until they can feed themselves.
Nest Departure
After 18-28 days in the nest, the hatchlings are fully feathered and ready to fly. They leave the nest and start life on their own. The female then may start a second brood.
Threats and Predators
Ruby throated hummingbirds face threats from weather, habitat loss and predators during the breeding season:
- Severe storms or cold snaps
- Deforestation and habitat loss
- Nest parasitism by cowbirds
- Predators including jays, squirrels and snakes
- Collisions with windows or cars
Despite these hazards, ruby throated hummingbirds continue to thrive over a wide breeding range. Their resilience enables the species to bounce back from periodic regional declines.
Weather Extremes
Cold snaps or severe storms during the breeding season can kill adults, eggs and nestlings. However, impacts are normally short-term and localized.
Habitat Loss
Deforestation and development that removes forests and meadows reduces breeding habitat. But ruby throats remain common where any flowers exist near trees.
Brood Parasites
Ruby throats may be victimized by brown-headed cowbirds that lay eggs in their tiny nests. But hummingbirds often build a new nest on top of the existing one to bury cowbird eggs.
Nest Predators
Common nest predators include blue jays, squirrels, snakes and cats. But new nesting attempts are frequent and clutch sizes are small, limiting impacts.
Collisions
Nesting near human structures leads to collisions with windows and cars that can kill individuals. But wide overall distribution provides resilience.
Conclusion
In summary, ruby throated hummingbirds breed across a broad range of eastern North American forests, parks and gardens from southern Canada to the Gulf Coast. Within this range, they nest in diverse habitats from deciduous forests to pine woods wherever flower nectar availability allows. Their resilience in the face of threats enables thriving breeding populations across most of their historic range. With a little help from humans in providing flowers, shrubs and nesting sites, ruby throated hummingbirds will continue flourishing each spring.
