Blog Archive: Fun Facts

Birdorable Superb Fairywren

Bird Term: Sexual Dimorphism

November 12th, 2015 in Bird Terms, Fun Facts 4 comments
Supurb Fairy Wrens

Sexual dimorphism refers to observable differences between males and females of the same species. In basic terms, it means that a male of a species is easily distinguished from a female. In birds this usually means differences in size or in plumage. It can also be noted in behavior differences and other traits.

Earlier on this blog we talked about the extreme sexual dimorphism in Eclectus Parrots, where males and females show extreme differences in their plumage: males are bright green while females are shades of red and blue.

Sexual dimorphism exists in most species of raptor. In birds of prey, males are often smaller than the females of the species. However, this is often difficult to discern in wild birds, especially if seen at a distance or when only one bird is present.

Many common birds also exhibit sexual dimorphism. Male ducks are often colorful, while females tend to be drab. You can see this in the common Mallard.

Mallard ducks
Mallard ducks by Connor Mah (CC BY-SA 2.0)

In songbirds, males may be brightly colored while females have a similar plumage with more muted tones, as seen in Baltimore Orioles, American Robins, Eastern Towhees, and Black-throated Blue Warblers.

Eastern Towhee, female and male
Eastern Towhees: female (left) by Brian Henderson (CC BY-NC 2.0), male (right) by Dendroica cerulea (CC BY-NC-SA 2.0)

In other birds, like the Eclectus Parrot mentioned above, the plumage differences are extreme. Examples of this can also be seen in the Superb Fairywren of Australia, and the Sage Grouse.

Can you think of other bird species where the male is easily told apart from the female? Do you have birds like this where you live? What about birds that aren't sexually dimorphic? Can you think of species where male and females are impossible to tell apart by looking at them?

Birdorable Green Aracari

Fun Facts About Toucans

September 10th, 2015 in Fun Facts, Toucans 2 comments
Birdorable Toco Toucan

There are about forty different species of toucan, spread over five genera. These include toucans and their smaller cousins, aracaris and toucanets. Here are some fun facts about the toucan family.

  • All toucans have colorful and extremely large bills. Despite their size, the bills are composed of a kind of spongy material, and are extremely lightweight.
  • Having a large bill is beneficial in foraging for fruit -- the bird can grab a lot of food without moving its whole body. The oversized bill also helps the toucan regulate its body heat in the steamy rainforest.
  • Toucans are cavity nesters, but they aren't able to excavate their own nest holes with much success. They use cavities excavated by other birds, like woodpeckers.
  • The smallest birds in the family range from about 11 or 12 inches long (the Green Aracari or the Lettered Aracari).

Aracari, Green
Green Aracari by Sham Edmond [CC BY 2.0]

  • The largest species of toucan is the Toco Toucan, which reaches 29 inches in length.
  • Toucans are able to fly, but they have relatively short wings. They are resident birds within their range (they do not migrate), and tend to get around their forest canopy habitat by hopping from branch to branch.
  • The Toco Toucan is the most well-known species of toucan; it is sometimes known simply as "Toucan" or "Common Toucan".

Toco Toucan by William Warby [CC BY 2.0]

  • The Keel-billed Toucan is the national bird of Belize.
  • Toucans are found in the Neotropics, meaning they are New World birds found in tropical habitat. They range from southern Mexico into northern parts of South America. They are also found in the Caribbean.
  • The constellation Tucana, a group of stars in the Southern Sky, is named after the toucan. It was established by Dutch astronomer Petrus Plancius and was first published in 1598 in Amsterdam.
  • We have three birds in the toucan family here. Check out our Birdorable Keel-billed Toucan, Birdorable Green Aracari; and Birdorable Toco Toucan!
Birdorable Lappet-faced Vulture

Glossary of Vulture Terms

September 4th, 2015 in Fun Facts, Vultures 2 comments


In today's post we're sharing some keywords that pertain to vultures. This vulture glossary also includes definitions that apply to other bird families, but are important topics to understand when learning about vultures.


If you're going to be talking about vultures, you are inevitably going to be talking about carrion, because that is what most vultures eat. Carrion is the decaying flesh of a dead animal. Other scavengers that consume carrion besides vultures include eagles, opossums, coyotes, and some beetles.

Turkey Vulture with road kill carrion

Convergent Evolution

Vultures in the New World (the Americas) are not closely related to Old World (Europe, Asia, and Africa) vultures. Since many vultures of both types have similar features like bald heads and scavenger behavior, how can it be that they are not closely related? The answer is convergent evolution. Broadly, this refers to organisms evolving similar traits while lacking a common ancestor. Birds, flying insects, and bats are not related, but they have all evolved the capacity to fly. Similarly, vultures in both the Old and New Worlds have evolved special traits to help them specialize in feeding on carrion. With few exceptions, no matter their location, vultures fill a similar niche in the ecosystem.


The crop is an expandable part of the digestive tract of birds and some other animals. The muscular pouch, close to the throat, is used to store food before digestion. The full crop of the Lappet-faced Vulture can hold up to 3.3 lb of meat!


Vultures are known to gorge themselves at feeding sites. They will eat until their crop is completely full, and then sit full, digesting their food. It is thought that vultures sometimes gorge themselves to the point of being unable to fly.

Vultures kettling in the sky


A group of vultures in flight together, particulary soaring on thermals, is known as a kettle. Kettle may describe other birds flying in this way, including mixed flocks which may or may not have vultures.


Preening is the act of cleaning or grooming. Birds, including vultures, preen themselves to keep their feathers in top shape. Allopreening refers to social grooming between multiple individuals, often performed to strengthen social bonds. Black Vultures are known to take part in allopreening at roosting and feeding sites. Often allopreening concentrates on the head area, a spot that a bird cannot easily reach with its own beak.

Vulture preening
White-backed Vulture Preening by Sascha Wenninger

Stomach Acid

Vultures have extremely corrosive stomach acid, which helps them to safely digest dead animals that may be infected with diseases and toxins. The stomach acid protects the birds from contracting and spreading disease. Gut bacteria in vultures helps them to withstand several kinds of toxins that may be found in decaying flesh.


Taxonomy is a scientific system for naming and organizing living things which share certain characteristcs. The taxonomy of vultures can be confusing. New World and Old World vultures aren't closely related, despite their physical and behavioral similarities. Some scientists think that New World vultures are closely related to storks. With new advances in the study of DNA, sometimes single species are split into distinct species. The Long-billed Vulture was split into two distinct species: the Slender-billed Vulture and the Indian Vulture. The Yellow-headed Vulture was split into two species in the 1960s: the Lesser and Greater.

Split vulture species

The big day is almost here! Tomorrow our Vulture Week will conclude on International Vulture Awareness Day!

Birdorable Eurasian Griffon

Vulture Week: Vulture Extremes




Largest Vulture

Smallest Vulture

Compare sizes of Andean Condor vs. Palm-nut Vulture

Vulture Longevity Records

Most Abundant Vulture

Turkey Vultures (Cathartes aura) Preflight Warmup
Turkey Vultures by docentjoyce (CC BY 2.0)

Fastest Decline

Longest Migration

Ancient Birds

Highest Flyer


Birdorable Spectacled Owl

Owls Have Amazing Eyes

August 21st, 2015 in Fun Facts, Owls 4 comments
Birdorable Owls Portrait

Owl eyes are pretty amazing.




and you are sure about that ?


American Bittern by Amy Evenstad for Birdorable



Nictitating Membrane


Birdorable Western Tanager

North America's Tanagers

August 6th, 2015 in Fun Facts, Tanagers 1 comment
Birdorable tanagers on a branch


Tanagers in name only?
There are four species of tanager found in North America. These are the Western Tanager, Summer Tanager, Scarlet Tanager, and Hepatic Tanager. They are in the genus Piranga and are thought to be closely related to cardinals; they may not belong in the tanagers' Thraupidae family at all.

Colorful Across the Americas
In total there are over 200 species of tanager. Most are found in tropical habitats, and many species have relatively small native ranges. For example, the Green-headed Tanager is found along a narrow strip extending from southeast Brazil down into southeastern Paraguay and northeast Argentina.

Western Tanager

Western Tanager by Pacific Southwest Region USFWS [CC BY 2.0]

Western is Most North
North America's Western Tanager is notable for being the northern-most ranging species of tanager. This migratory species breeds as far north as Canada's Northwest Territories. They spend the winters in Central America.

Hepatic: I'm Huge in South America
In the United States, the Hepatic Tanager is only found as a breeding bird in the southwestern mountains. However, the species has a very large native range and many birds are permanent residents across a large portion of South America.

Summer's Pretty Song
Most tanagers are not known for their pretty song, but the Summer Tanager is an exception. It sings a melodic tune that reminds many of the American Robin's song.

Scarlet Tanager

Scarlet Tanager by Kelly Colgan Azar [CC BY-ND 2.0]

Cowbird's Target
The Scarlet Tanager is particularly susceptible to brood parasitism from Brown-headed Cowbirds. Being forest nesters, they never developed a strategy against the rogue-nesting cowbirds. Segmented habitat (due to human developement) means tanagers more often nest near open habitats favored by cowbirds, rather than deep inside old-growth forests where cowbirds rarely occur.

Ripe Old Age
The longevity record for wild Western Tanagers is nearly seven years; for wild Summer Tanagers it is nearly eight years; and for wild Scarlet Tanagers the record is nearly twelve years. These records were collected via bird banding.