Hummingbirds are amazing little birds that capture the imagination. Their small size, beautiful plumage, and incredible flying abilities make them a joy to watch. One of the most fascinating aspects of hummingbird behavior is their nest building. Hummingbirds build intricate, tiny nests each breeding season in order to lay and incubate their eggs and raise their young. But when exactly do hummingbirds build their nests? What cues tell them that it’s time to start nesting activities? Let’s take a closer look at hummingbird nesting seasons and learn more about when these aerial acrobats get to work building their nests.
The Nesting Season Varies by Species and Region
There is no one simple answer to the question of when hummingbirds build nests, as different hummingbird species in different regions may nest at different times of the year. The timing of nesting is closely tied to the blooming of flowers that provide nectar for the birds. Here are some general guidelines:
- In most of the United States, the nesting season for hummingbirds such as ruby-throated hummingbirds and rufous hummingbirds is between March and June.
- In the warmer southern states such as Florida, Texas, and Arizona, some hummingbirds may nest as early as January or February.
- In cooler northern states and Canada, nesting may start as late as May or extend into July.
- Western hummingbirds like Anna’s and Allen’s hummingbirds may nest from December to June in their range along the Pacific Coast.
- Tropical species like mangoes, coquettes, emeralds, and mountain gems nest at various times of year correlated with peak flower blooming.
The key factor influencing when hummingbirds build nests is an abundance of flowers from which they can feed. Different species time their breeding to match peak food availability in their environment. This ensures there will be enough nectar to fuel the high energy demands of nesting, incubating, and rearing chicks.
Most Nest Building Takes Place Between March and June
While there is variation among species and regions, the majority of hummingbirds in the U.S. and Canada build their nests between March and June. Here are some reasons why:
- In most areas, flowers are blooming abundantly by early spring, providing food for nesting birds.
- Insects, which adult hummingbirds eat and feed their chicks, become active and plentiful in spring providing plenty of protein.
- Spring and early summer provide moderate temperatures suitable for incubating and rearing young before the heat of summer arrives.
- Nesting in this time period allows time for raising one or two broods of chicks each season.
So while a few very early and very late nesters exist, March to June is considered peak hummingbird nesting season in most of their North American range.
Exact Timing Depends on the Arrival of Males and Females
Within that spring nesting window, the exact timing of nest building depends on when the male and female hummingbirds arrive in a given area. Here are some more details:
- Male hummingbirds arrive first on the breeding grounds in spring and establish nesting territories.
- Females arrive approximately 1-2 weeks after the males.
- Males display to court females by making aerial displays and dive displays over their territory.
- Once females arrive, breeding takes place within days and the female begins gathering nest material.
- Nest building begins within 1-2 weeks of the females’ arrival once breeding has commenced.
So the appearance of males in an area signals nesting time is approaching. But it is the arrival of the females that actually triggers the beginning of nest construction within a few weeks. Tracking the movement of males and females is a good way to predict peak nesting time.
Nest Building Takes 10-15 Days On Average
Once a female hummingbird begins constructing a nest, the building process takes approximately 10-15 days on average. Here is the general timetable:
- Days 1-4: The female gathers soft plant down, spider silk, bud scales, moss, and lichens and forms a base for the nest.
- Days 4-8: The female collects plant fibers, thin bark strips, hairs, and feathers. She intricately weaves these around the base to form the outer walls.
- Days 8-10: The female lines the inside of the nest with soft plant down and spider silk to cushion the eggs.
- Days 11-15: The female continues adding material to strengthen and expand the nest walls as needed.
Nests are often built high in trees and in sheltered nooks, like on small outer branches underneath larger branches or leaves. The female may build a few different partial nests before settling on a final nest to complete. The finished nest is only 2-3 inches wide and 1-2 inches tall—a marvel of construction to hold eggs smaller than jellybeans.
Nest Sites Offer Camouflage and Shelter
Hummingbird nests may be tiny, but they are built to be durable, secure, and camouflaged. hummingbird females carefully choose nest sites with protective features:
- Under hanging branches or leaves to shelter from rain, sun, and wind.
- High up in trees or shrubs away from tree trunks to hamper predators.
- In deciduous trees so leaves sprouting around the nest conceal it.
- Tucked into a fork or branch junction for sturdy attachment.
- Over waterways, lakes, or canyons to deter crawling predators.
Nests materials are chosen to blend into the surroundings. Female hummingbirds also decorate the outside with lichens or moss to help the nest further resemble its placement. Careful site selection helps prevent nests from being damaged by weather or located by predators.
Hummingbird Chicks Hatch Within Weeks
Once the nest building is complete, the female lays a small clutch of eggs, usually just 2 eggs. The eggs are the size of a coffee bean. She will incubate the eggs for approximately 14 to 23 days before they hatch. Timeframes vary slightly by species. Once hatched, the altricial chicks will remain in the nest anywhere from 18 to 28 days while the female feeds and cares for them. They depend completely on their mother during this time.
Within 1 to 2 months after nest construction first began, the chicks are ready to fledge from the nest. Nest building, egg-laying, incubating, hatching, and rearing happens remarkably quickly for these tiny birds. This allows them time to raise multiple broods in a single breeding season.
Late Summer and Fall Nests Are Less Common
While the core nesting period is early spring through early summer for most hummingbirds, some species may build a small percentage of nests later in mid to late summer. There are a few reasons this may occur:
- Younger females may not nest until later in their first summer.
- Females may build a second nest for a second brood after successfully fledging an early brood.
- Some birds attempting to nest earlier may fail, losing eggs or chicks to weather, predators, or other factors, prompting them to try nesting again.
- Late blooming flowers provide food allowing late nesting in some regions.
However, the percentage of late summer/fall nests is generally small. Most activity still centers on the core spring to early summer season when conditions are optimal. Nesting too late risks chicks still being dependent when harsh winter weather arrives.
Nests Are Abandoned After Chicks Fledge
Hummingbird nests are single-use structures. Once the chicks successfully fledge and leave the nest, the nest is abandoned. The now empty nests are often blown down by wind and rain. Nests are so small and fragile that they cannot withstand much weather once they are no longer actively maintained by the female.
Hummingbirds build completely new nests each year. They do not repair old nests or re-use them for second broods. Pairs may build at a previous successful site. But the male and female will construct a brand new nest together each spring using fresh gathered materials. The nests are meant to only last a single nesting cycle.
Climate Change May Affect Nesting Timelines
Rising global temperatures due to climate change may cause shifts in flowering and nesting timelines for hummingbirds in the coming decades. Here are some potential climate change impacts:
- Flowers blooming earlier may prompt earlier nesting.
- Heat waves may desynchronize flowers and nesting times.
- More frequent droughts may reduce food availability.
- Increased severe weather may damage nests.
- Expanding ranges north may extend nesting seasons.
Researchers are still studying how the timing of pollinator lifecycles may be impacted. But hummingbirds may need to shift nesting times to match new flower and insect availability in their areas as climate patterns change. This could mean hotter, drier areas see reduced nesting success, while more poleward areas see expanded nesting seasons.
Protecting and Providing Habitat Is Crucial
To help hummingbirds continue thriving and nesting successfully, habitat conservation is key. Here are some ways to support hummingbirds:
- Plant native nectar flowers and pollinator gardens providing food through the nesting season.
- Avoid use of pesticides which reduce insect food supplies.
- Provide hummingbird feeders for supplemental nectar.
- Install nesting shelves or boxes where trees are sparse.
- Ensure access to water for drinking and bathing.
- Limit tree removal which decreases nest sites.
- Reduce urbanization impacts on their specialized habitat needs.
With a little help, these aerialartists can continue gracing our skies with theirbeauty and fascinating behaviors like nestbuilding.
Conclusion
Hummingbirds build their small but complex nests primarily in the spring months between March and June in most of North America. While a few species in southern or coastal areas may nest very early or late in the year, the peak activity centers on the longer days, moderate temperatures, and flower abundance of spring. The exact timing within this peak window depends on the arrival of males to establish territories and females to start gathering materials. But once nest building begins, hummingbird pairs work rapidly to build a nest, lay eggs, incubate, and rear a brood within a matter of months. Understanding their nesting ecology helps us support these special birds on their breeding grounds and beyond.
