Hummingbirds are some of the smallest birds in the world, and Costa Rica is home to over 50 species of these tiny, colorful creatures. Their diminutive size is one of the things that makes hummingbirds so fascinating – some species have an average body length of just 5-6 centimeters. But hummingbird sizes can vary depending on the species, age, gender, and geographic location. In this article, we’ll take a closer look at the sizes of hummingbirds found in Costa Rica.
How small are hummingbirds?
Hummingbirds are the smallest birds in the world. The bee hummingbird, found in Cuba, is the smallest living bird, with an average body length of just 5-6 cm and a weight of 1.6-2 grams. That’s smaller than a U.S. penny! Most hummingbird species are not much larger than the bee hummingbird. The second smallest hummingbird is the Calliope hummingbird, found along the Pacific Coast, which measures 6-7 cm. Even the largest hummingbird, the giant hummingbird found in South America, is only about 22 cm long. So all hummingbird species are tiny compared to other types of birds. Their small size allows them to hover in midair, fly backwards, and access nectar from flowers not available to larger birds.
What is the average wingspan of Costa Rican hummingbirds?
Most Costa Rican hummingbirds have wingspans between 7.5-13 cm. For example, the purple-crowned woodnymph has an average wingspan of 11 cm. The green-crowned brilliant’s wingspan is around 7.5 cm. Larger species like the violet sabrewing have wingspans up to 13 cm across. Females tend to be slightly larger than males. The wings of hummingbirds beat up to 80 times per second, allowing them to fly like helicopters and precisely control their position while feeding on flower nectar. Their rapid wingbeats produce the characteristic humming sound.
How much do hummingbirds weigh?
The average weight of Costa Rican hummingbirds ranges from 2-12 grams. That’s lighter than a nickel! For example:
– Violet sabrewing: 7-10 grams
– Green-crowned brilliant: 3-4 grams
– Coppery-headed emerald: 4-5 grams
– Purple-crowned fairy: 2-3 grams
The larger hummingbird species like the violet sabrewing weigh just under 1/3 ounce. The smaller species like the purple-crowned fairy weigh just a tenth of an ounce. Their light weight allows them to hover and access nectar from the smallest, most delicate flowers.
Sizes of Common Costa Rican Hummingbird Species
Here is more detail on the sizes of some of the most common hummingbird species found in Costa Rica:
Violet Sabrewing
| Average Length | 15 cm |
| Wingspan | 13 cm |
| Weight | 7-10 g |
The violet sabrewing is one of the larger hummingbird species found in Costa Rica. Its vibrant violet coloration makes it stand out. The male has a curved black bill that is an adaptation for accessing nectar from certain curved flowers.
Green-crowned Brilliant
| Average Length | 11 cm |
| Wingspan | 7.5 cm |
| Weight | 3-4 g |
True to its name, the green-crowned brilliant flashes iridescent green and blue plumage in the sunlight. The male has a distinctive punk-style crest on its head. This species is one of the smaller Costa Rican hummingbirds.
Coppery-headed Emerald
| Average Length | 9 cm |
| Wingspan | 5 cm |
| Weight | 4-5 g |
The coppery-headed emerald gets its name from the coppery sheen on the male’s head and neck feathers. As an “emerald” species, it flashes bright green plumage in flight. Its small size allows it to hover while feeding on small flowers.
Purple-crowned Fairy
| Average Length | 7.5 cm |
| Wingspan | 8.5 cm |
| Weight | 2-3 g |
The aptly named purple-crowned fairy is one of the very smallest hummingbird species in Costa Rica. The male has an iridescent purple crown, while the female’s crown is drabber gray. This tiny bird weighs just a few grams!
Size Differences Between Males and Females
In most hummingbird species, the males are slightly larger than the females. Here are some size differences:
Crowned Woodnymph
| Male | Female | |
| Length | 12 cm | 10 cm |
| Wingspan | 12 cm | 10 cm |
| Weight | 5-6 g | 4-5 g |
The male crowned woodnymph has noticeably larger dimensions than the female. The difference is especially apparent in the longer, more deeply forked tail of the male.
Rufous-tailed Hummingbird
| Male | Female | |
| Length | 9 cm | 8 cm |
| Wingspan | 5 cm | 4.5 cm |
| Weight | 3 g | 2.5 g |
In the rufous-tailed hummingbird, the male again exceeds the female in all dimensions. The difference in weight of half a gram is significant for these tiny birds.
Changes in Size with Age
Hummingbird size changes significantly as the birds mature:
Newly Hatched Chicks
Hummingbird chicks are tiny when they first hatch from their pea-sized eggs. A new chick weighs just 0.6 grams on average – that’s less than a paper clip! They do not yet have functioning wings and legs. Their eyes are closed, and they have just a bit of downy plumage.
Developing Nestlings
Over the next couple weeks, hummingbird chicks grow quickly in the nest. Their wings and legs develop, their eyes open, and they get their first coat of feathers. By the time they are ready to fledge, a nestling can weigh 4-5 times more than when first hatched.
Juveniles
Once they leave the nest, juvenile hummingbirds reach about 3/4 of their adult size. Their feathers lack the iridescent colors of adults. As they practice flying and feed on their own, juveniles continue growing for their first few months.
Adults
Adult hummingbirds do not grow anymore in length. However, they may still put on a bit more weight with age. Adult male hummingbirds take at least one year to grow their full iridescent plumage. The adult female looks much the same from her first year onward. Her size remains constant unless impacted by habitat resources.
Factors Affecting Hummingbird Size
Several factors contribute to the average and maximum size of hummingbirds in a given habitat:
Climate
Costa Rica’s tropical climate allows hummingbirds to be active year-round. This constant access to food resources supports the energy needs of larger hummingbird species. Colder climates limit food supplies, restricting the size hummingbirds can maintain.
Habitat Quality
Abundant flowers, nesting sites, insects, and tree cover in rainforest habitats enable Costa Rican hummingbirds to reach maximum sizes. Degraded habitats with fewer resources can result in smaller adult sizes.
Competition
Larger hummingbird species use their size to dominance nectar resources. Smaller species may be excluded from the best feeding areas. This competition for food influences size capabilities.
Predators
Predation pressure from birds and insects favors smaller hummingbird species that are more agile and evasive. Larger species are able to survive despite their visibility due to behaviors like jabbing with their bills.
Nesting
The stability of nest sites affects hummingbird nesting success. More secure nests allow raising bigger chicks to fledging. Frequent storms or predators can reduce growth of chicks.
Changes in Hummingbird Sizes Over Time
Researchers have found that some hummingbird species are evolving smaller average sizes over decades:
1968 vs Today
In 1968, eight species of Costa Rican hummingbird had an average length over 11 cm. Today just two species average over 11 cm. The other six have decreased in length by an average of 5-11%. These reductions correlate to habitat loss.
Factors Driving Size Reduction
Climate change, fewer flowers due to deforestation, more predators, and pesticide use may contribute to these decreases in hummingbird size over five decades. The smaller birds are more adaptable to degraded habitats.
Future Adaptations
This size reduction suggests hummingbirds are evolving to sustain their populations as ecosystems change. Further declines in average size and weight are likely for some species as climate impacts worsen. Maintaining habitat diversity will support continued survival of a range of hummingbird sizes.
Conservation Importance of Diverse Sizes
Preserving Costa Rica’s hummingbird diversity means protecting species across the size spectrum:
Small Species
Tiny hummingbirds play specialized roles in pollination and food webs. The bee hummingbird coevolved with Cuba’s smallest flowers. Loss of diminutive species would disrupt plant reproduction.
Medium Species
Mid-size hummingbirds with adapted bill shapes can access resources dominant species overlook. Their flexibility makes them resilient to some habitat changes. Keeping these resilient species abundant preserves ecosystem functions.
Large Species
Largest species fill roles as apex pollinators and predators. The giant hummingbird deters bees from some flowers. Violet sabrewings may defend whole forest territories. Large rivals keep mid-size species on the move to spread pollen.
Balance is Ideal
Ideally, conservation efforts will maintain a spectrum of hummingbird traits and functions. Complete communities allow species to adjust and adapt together in changing environments through beneficial interactions.
Summary of Key Facts on Hummingbird Sizes
– All hummingbirds are tiny, ranging from 5 cm to 22 cm in length
– Wingspans range from 5 cm to 13 cm across
– Weights span just 2-12 grams, with larger species under 1/3 ounce
– Males tend to be slightly larger than females
– Chicks start under 1 gram, growing rapidly to fledging size
– Adult size is reached in first year, but weight may increase with age
– Some species have declined in size over recent decades
– Diversity of sizes allows hummingbirds to fill a variety of roles
Conclusion
While all hummingbirds are impressively small, they do come in a range of sizes with meaningful implications for their ecology and evolution. Costa Rica hosts an array of hummingbird species spanning tiny bee-sized birds to relatively giant hummingbirds over 20 cm in length. Their diverse adaptations in size, shaped by complex environmental pressures, allow these energetic creatures to pollinate, propagate, and persist across a variety of tropical habitats. Protecting the full spectrum of hummingbird biodiversity has cascading benefits for Costa Rica’s incredible rainforests and the many species that call them home.
