Bird beaks and feet
The beak of a bird consists of toothless jaws and a mouth opening that is usually elongated into a pointed shape. It is covered with a
lightweight, horny, epidermis and is used in the way that you would use a pair of forceps. The base of the beak lacks feathers and
may be somewhat scaly.
The legs or birds are functionally similar to our legs. On the ground or on a perch, the legs of a bird support the entire weight of its
body. The leg is constructed like a lever to combine walking and running ability with “take off” capability. A standing bird has its
knees directed forward. When a bird perches, its leg bones jack-knife, pulling the ankle tendons taut and clinching the toes around
the perch. The bird is thus “locked” on to the perch and can sleep without falling off. It must raise its whole body to straighten the
legs and loosen the ankle tendons before it can unlock its fee. Bird legs generally lack feathers; instead, they’re covered with scales
similar to those of reptiles. Bird feet generally have 4 toes, which end in claws. The first big toe is called the hallux and sometimes
will be turned backwards.
An animal’s habitat includes its food, water supply, shelter and territorial requirements. Sometimes an animal finds shelter in one
type of environment and food in another. For example, a hawk may find shelter in wooded areas and hunt rodents in a neighboring
meadow. Its ideal habitat could be described as a combination of wooded area and meadow.
1.
Use the beak type and function table to complete the beak adaptation columns on your bird data table. What is a
description of their beak and what food would the bird eat?
Beak type
Short and stout
Spear-shaped and stout
Chisel-shaped
Hooked
Tubular
Stout and long
Flat, slight hook
Medium length, medium width and slightly turned down
Long and slim
2.
3.
Function
Eating small insects
Spearing fish
Drilling for insects
Catching and tearing prey
Sucking nectar
Scooping up fish
Straining algae and small organisms
Multipurpose
Probing
Use the bird feet and legs function table along with the bird beak and feet chart to complete the feet adaptation columns
on your bird data table. What is a description of their feet and what would they be used for?
Bird feet and legs
2 toes in front; 2 behind
Sharp, slender claws
Function
Climbing and clinging
3 toes in front; 1 behind
Long legs, long toes
Short legs, blunt, stout claws
Medium length legs, rounded toes
Webbed feet
Large, hook-like claws
Very short, weak legs
Wading
Scratching
Perching
Swimming
Grasping prey
Hovering or sitting close to branches, flowers
Classify the birds you have looked at by the type of habitat to which each would be ideally suited and complete the habitat
column on your bird data table. Enter these data into your Bird Data Table. Habitats might include wooded area, meadow,
lake, shoreline or some combination of these areas.
Most birds have tongues, though unlike ours. Most bird tongues do not have muscles but have 5 bones in it that support and
strengthen it. There is also a great deal of variation in bird tongues. A bird's tongue is generally harder and less flexible than ours.
Like bird beaks, bird tongues are specialized to each particular bird’s way of feeding.
4.
Read the description of bird tongues below and write down what that bird would eat.
a.
The tip of the tongue has many little protrusions giving it a frayed or brush-like appearance.
Food _____________________________________
b.
Type of bird: Swift parrot
A split tongue with each half being able to unfurl and furl allowing it to lap up liquid.
Food _____________________________________ Type of bird: Anna’s hummingbird
c.
A long tongue which is sharp and spiky at the end.
Food _____________________________________ Type of bird: Red-bellied woodpecker
d.
Pointed with rear-facing hooks or spikes.
Food _____________________________________ Type of bird: Red breasted merganser
e.
Wide, hairy and spiky tongues.
Food _____________________________________ Type of bird: Cinnamon teal
f.
Blob-like with muscles to manipulate food.
Food _____________________________________ Type of bird: American kestrel
g.
Rows of teeth on the tongue that undulate and work like a conveyer belt.
Food _____________________________________ Type of bird: King penguin
Questions
1.
Why don’t perching birds fall out of the tree when they sleep?
2.
What was a perching bird to release its grasp?
3.
What is a hallux?
4.
Why is the hallux so long in raptors, such as eagles and hawks?
5.
How are the feet of a White Pelican different than the feet of a Western Grebe?
a.
How are their functions similar?
6.
Sometimes the beak of an American Crow is described as being a “Swiss army knife.” Explain what this means.
7.
What insects have the same feeding behavior as a Calliope Hummingbird?
8.
Grebes, Herons and Pelicans frequently live together at the same lake and all three eat fish. There is a principle in ecology
that states no 2 species can occupy the same niche (way of life) in any one location or habitat. How do these three species
conform to this principle?
9.
What would be the function of the foot shown below?
a.
Name a bird that would have this type of foot.
10. Penguins have a highly developed circulatory system. How could this adaptation help keep the feet of penguins from
freezing or loosing too much heat?
11. Some species of Swifts have the ability to have all four of their toes facing forward. What would this type of foot be used
for?
12. A crossbill is a bird that lives in conifer forests. Notice how the tips of its beak don’t line up evenly, giving the bird its name.
a. What specific food item would this bird eat?
Bird Data Table
Name of Bird
Northern Flicker
Gambel’s Quail
Black Capped
Chickadee
White Ibis
Spotted Owl
Western Grebe
White Pelican
Calliope
Hummingbird
Green Heron
American Crow
Pintail
Beak Adaptation
Description
Possible Food
Feet Adaptation
Description
Possible Function
Habitat
Bird beak and feet chart
Name of Bird
Northern Flicker
Gambel’s Quail
Black Capped Chickadee
White Ibis
Spotted Owl
Western Grebe
White Pelican
Calliope Hummingbird
Green Heron
American Crow
Pintail
Picture
Beak Diagram
Feet Diagram