Quick Answer
Ruby-throated hummingbirds typically lay eggs in late spring to early summer. The exact timing varies depending on the region, but incubation generally takes place from May through June in most of their breeding range.
Breeding Season
Ruby-throated hummingbirds have a relatively short breeding season compared to other bird species. Here are some key facts about their nesting and egg-laying timeline:
- Courtship and mating occurs in early spring when the males return from migration. In southern areas, this can begin as early as February or March.
- Nest building typically takes place in April and May.
- Egg laying normally occurs between late April and early June.
- Incubation lasts around 12-14 days.
- The nestling phase lasts 18-28 days, with the young fledging in late June to early July.
- Ruby-throats raise one brood per season, then migrate south again for the winter.
The exact timing varies across their range. In southern states like Florida and Texas, nesting and egg-laying may begin a few weeks earlier than further north. The table below shows the approximate nesting timeline in different regions:
| Region | Nest Building | Egg Laying | Incubation |
|---|---|---|---|
| Southern States (e.g. FL, TX) | March – April | April – May | May – June |
| Mid-Atlantic and Midwest | April – May | May – June | May – July |
| Northeastern States | May | May – June | June – July |
| Southern Canada | May | June | June – July |
Clutch Size
Female ruby-throated hummingbirds typically lay 2 eggs per clutch. The eggs are small, white, and elliptical in shape. Some key facts about their eggs:
- Clutch size is almost always 2 eggs.
- The eggs measure about 0.6 inches long and 0.4 inches wide.
- Eggs are laid 1-2 days apart.
- If a clutch is lost, the female may lay another.
- Incubation doesn’t start until both eggs have been laid.
- The tiny nests measure around 1.5 inches wide and 1 inch deep.
The female incubates the eggs alone. She sits very tightly on the nest, only leaving briefly a few times a day to forage for nectar.
Number of Broods
Ruby-throated hummingbirds raise just one brood per breeding season. They arrive on the breeding grounds relatively late and have a short period of peak food availability. Raising a single brood allows them to maximize resources during this time.
Some key facts about their breeding habits:
- Females lay eggs for one clutch, raising a single brood.
- They do not reuse the same nest for a second brood.
- Late or lost clutches may be re-laid, but this is one replacement clutch.
- Double brooding is extremely rare in ruby-throats.
- They migrate south soon after the young fledge from the nest.
This differs from some species like Anna’s and Black-chinned hummingbirds that may raise two broods per season in areas with a longer breeding period. The ruby-throats’ short nesting season precludes them from having more than one successful clutch.
Range and Habitat
Ruby-throated hummingbirds nest across most of eastern North America. Their breeding range extends from southern Canada through the eastern United States. Some details:
- Breed in all eastern U.S. states from Texas to Florida to Maine.
- Range extends northwest into central Canada through Manitoba and Saskatchewan.
- Found along the Gulf Coast and up the Atlantic seaboard.
- Prefer open or semi-open habitats with meadows, forests, and gardens.
- Readily use backyard feeders when breeding.
Within their widespread breeding grounds, ruby-throats are found in a variety of semi-open environments. They thrive in areas that provide both feeding habitat and nest sites, particularly in edges between meadows and woodlands. Backyards with flowers and feeders also help support breeding.
Migration
Ruby-throated hummingbirds migrate huge distances each year between their breeding and wintering grounds. Their migration impacts their breeding timeline and seasonality.
- Most leave the U.S. Gulf coast by September.
- Fall migration happens over an extended period from August-November.
- They winter primarily in Mexico and Central America.
- Arrive back on breeding grounds as early as February in the south.
- Migration means a very compressed nesting season.
The vast majority of ruby-throats make this long round-trip journey annually. This shapes their breeding behavior and limits it to a tight seasonal window in the spring and summer months.
Conclusion
In summary, ruby-throated hummingbirds typically lay eggs from late April through early June depending on the specific region. The overall breeding season lasts only a few months, with most activity centered around May. Females lay 2 eggs per clutch and raise just one brood before migrating in late summer. Their small clutch size but widespread breeding range makes the ruby-throat one of North America’s most abundant and recognizable hummingbird species.
