The Ruby-throated Hummingbird (Archilochus colubris) is one of the smallest bird species in North America. Despite their tiny size, Ruby-throated Hummingbirds are fierce competitors and can be very aggressive in defending food sources. Their diminutive stature also allows them to hover and fly backwards with amazing agility. But just how small are Ruby-throated Hummingbirds? Here we will explore the key size statistics of these tiny avian acrobats.
Average Length and Wingspan
The Ruby-throated Hummingbird measures on average just 3.1–3.5 in (8–9 cm) in length from the tip of its bill to the tip of its tail. This makes it one of the smallest bird species in North America. Only the Calliope Hummingbird is shorter, measuring 2.8–3.1 in (7–8 cm) on average. For comparison, American Robins measure around 9.1–11 in (23–28 cm) in length.
In terms of wingspan, Ruby-throated Hummingbirds range from 3.1–4.3 in (8–11 cm) across. The wings are short relative to the body, but allow for extremely quick wing beats that enable hovering and reverse flight.
Average Weight
Despite their tiny size, Ruby-throated Hummingbirds have very high metabolisms that require them to consume large amounts of nectar to fuel their active lifestyles. As a result, they have a surprising amount of weight relative to their diminutive stature.
On average, Ruby-throated Hummingbirds weigh just 2.0–6.0 g. To put that in perspective, a nickel weighs approximately 5 g. Some individual Ruby-throats in ideal condition before migration have been known to weigh over 7 g.
The small body weight allows Ruby-throated Hummingbirds to hover in place by rapidly beating their wings up to 53 times per second. Their heart rate can reach as high as 1,260 beats per minute as well. This high energy output requires an immense amount of food relative to their tiny size. Ruby-throats will consume approximately half their body weight in nectar each day!
Differences Between Males and Females
There are some slight size differences between male and female Ruby-throated Hummingbirds. Males tend to be larger, weighing an average of 3.4 g compared to 3.0 g for females. Males also have slightly longer wings and tails on average.
The bill of the male Ruby-throat is usually longer and straighter than that of the female as well. Female Ruby-throats tend to have bills that are more curved throughout their length.
| Measurement | Male | Female |
|---|---|---|
| Length | 3.5 in | 3.3 in |
| Wingspan | 4.1 in | 3.9 in |
| Weight | 3.4 g | 3.0 g |
Changes Throughout the Year
The size of Ruby-throated Hummingbirds can fluctuate significantly throughout the year as birds gain and lose weight.
Ruby-throats that have just completed the arduous migration north from Central America are typically at their lowest weight. Adult males arriving back on the breeding grounds in spring may weigh only 2.2–2.6 g on average. Females weigh even less at 2.1–2.4 g.
As the birds settle in and take advantage of plentiful food, they will rapidly put on weight. Males may gain over 20% of their body mass within the first two weeks back as they aggressively feed.
Just before migrating south again in late summer and fall, Ruby-throats will again be at their heaviest. This peak weight helps provide energy reserves for the long return migration. Males preparing for migration may weigh 3.6–3.9 g while females typically weigh 3.2–3.5 g.
Size Comparisons
It can be hard to visualize just how tiny Ruby-throated Hummingbirds are compared to other familiar animals and objects. Here are some size comparisons that put their diminutive stature into perspective:
– Ruby-throated Hummingbirds are slightly shorter in length than an American Penny which has a diameter of 0.75 in (19 mm).
– Their wingspan would just about match the diameter of a U.S. Quarter at 1 inch (24 mm).
– On average, 12 Ruby-throated Hummingbirds would need to be stacked up end-to-end to span one foot (30 cm).
– A single Ruby-throated Hummingbird weighs slightly less than two US pennies, which each weigh 2.5 grams.
– Two US dimes weigh about the same as one Ruby-throated Hummingbird at 3 grams.
– A teaspoon of water is equal to the average body weight of one Ruby-throat.
So while they may be the feistiest birds around the feeder, Ruby-throated Hummingbirds are still tiny and delicate creatures that belie their diminutive stature with their remarkable speed and aerial agility. Their small size and lightweight bodies allow them to hover and maneuver with ease as they aggressively defend nectar sources. The next time you see a Ruby-throat, remember that it only weighs as much as a teaspoon of water!
Conclusion
In summary, Ruby-throated Hummingbirds live up to their reputation as the smallest bird species in most of North America. With an average length of just 3.1–3.5 in and weight of 2.0–6.0 g, they are dwarfed by most other birds on the continent.
Their tiny size allows them to perform their signature hovering in place as they lick nectar from flowers at rapid rates. However, they also have very high metabolisms and need to consume up to half their body weight in nectar daily to maintain their energy levels.
While tiny, Ruby-throats punch above their weight class and will aggressively chase away larger birds from food sources or nesting areas. Next time you see one of these fiery feathered sprites, remember that it likely weighs about the same as two dimes!
