Raptors

RAPTORS

But those who wait on the Lord
Shall renew their strength;
They shall mount up with wings like eagles,
They shall run and not be weary,
They shall walk and not faint.
-Isaiah 40:31

-UNDER CONSTRUCTION - Last Updated February 13, 2026

Raptors are birds generally characterized by their sharp, curved talons, their sharp, powerful curved beaks, and their keen eyesight. The word “raptor” comes from the Latin “rapere,” meaning to size, to carry off by force. This well describes the feeding characteristics of most raptors, which generally capture live prey, grasp it with their talons, and use their beaks to kill and eat.

Generically, raptors are divided into two groups: diurnal (those active during the day) including the hawks, eagles, vultures, kites, and falcons, and nocturnal (those active at night) comprising the owls. From a scientific classification perspective (ie taxonomy), the raptors comprise three Orders within Class Aves (Birds): Accipitriformes (eagles, hawks, kites, vultures, and the single Secretarybird), Falconiformes (falcons and caracaras), and Strigiformes (the owls). Each group is subdivided into Families, which are further divided into Genera, and ultimately into individual Species.

A few Texas Raptors

Talons, Beaks, and Eyes

If the talons, beaks, and eyes of raptors serve as general characteristics common to the birds in this group, it is worth looking at some of the special features raptors have that adapt them to their particular lifestyles.

Talons/Feet: Raptors generally have very strong feet with sharp talons designed to capture and carry prey (the vultures are the exception, as they primarily feed on carrion, and thus do not need strong feet). In diurnal raptors the lower legs are often bare, but in many owls, the feather go all the way to the feet. The claws may be long and curved for those hunting fish, shorter for those hunting larger prey. Most raptor feet have three toes facing forward and a fourth facing backwards, but owls and osprey can turn their small toe backwards, to have a two-and-two configuration for better balance or grip. With the exception of the vultures (Cathartidae), most raptors capture live prey with their feet, using the talons to grasp and the strong muscular feet to hold on to often still live prey.

Raptors may hunt prey in the air, like our swift Cooper’s Hawk (Astur cooperii), which can maneuver in and around trees to strike mid-sized prey, including doves and pigeons, the Swainson’s Hawk (Buteo swainsoni), which can be seen catching bats above Bracken Cave, and the acrobatic American Kestrel (Falco sparverius), which catches insects on the wing and may be seen hunting as a family group. Others raptors strike at prey on the ground, including many of our owls seeking rodents, or even the Crested Caracara (Caracara plancus), which can often be seen in fields walking and hopping along looking for prey. Osprey (Pandion haliaetus) and Bald Eagles (Haliaeetus leucocephalus) catch fish, swooping down to grab them near the surface, or even on occasion diving under the water, talons-first, to strike and grasp their slippery dinner.

Beaks: The common raptor beak is hook-shaped, with a sharp pointed tip, designed to pierce and tear flesh, and also used to pull off feather and fur. Many falcons, and some hawks and other accipiters, have a special extra projection on the outside edge of the upper mandible (beak) just behind the sharp curved tip. This is called the Tomial Tooth, and may be matched by a notch in the lower bill called the Tomial Notch. The falcons use this to sever the spinal column of their small prey, quickly killing it. Like other birds, Raptors have a hinge on their upper jaw, allowing it to move independently of the head (something mammals cannot do). This allows them to open their mouth larger as needed, to re-grip prey, and get extra leverage in their “bite.”

Without teeth, raptors do not chew their food, they tear it and swallow in large chunks (or at times swallow small prey whole). Diurnal raptors have a crop, a “pouch” in their esophagus where they can initially store and soften food before moving it to the stomach for fuller digestion, but the owls do not. The owls are prone to swallowing their prey whole, and are less likely to be able to digest bones, fur, and feathers. Once they have drawn the nutrients from their digested prey, they compress the remaining materials into a pellet and regurgitate it. These are the owl pellets that we can dissect to know what was in the owl’s diet. Although diurnal raptors also make pellets, this is less likely as they are better at digesting difficult material, and larger raptors tear into their prey in order to mostly eat flesh, rather than bones, fur, and feathers. As usual, the vultures are a bit different. Vultures, which eat carrion, may have longer and straighter beaks, able to stick deeper into a carcass. Vultures also may have few or no feathers on their head, to avoid getting food in their feathers.

Eyes: Raptor eyes are very large for their head and point forward to allow binocular vision, which is important for determining distance to prey. Interestingly, many diurnal raptors have eyes that change color over their lifetime. Raptors have tetrachromatic vision, and thus have photoreceptors for red, green, blue, and ultra-violet light (the latter may facilitate ground hunting, as they can see the invisible trails of rodents). Diurnal raptors have very high concentrations of cones, providing excellent color vision, while nocturnal raptors have more rods, allowing them to detect movement and shapes even in very dim light. Overall, raptors are often said to have eyesight 8 times as powerful as humans, which may explain why they can see small prey far below when flying, and then keep that prey in sight as they swoop down for the kill.

Protecting the eye is a bony ring, called the sclerotic ring, which helps keep the eye safe from injury but, together with the large eye size that reduces placement for muscles in the skull, limits the raptor’s ability to turn its eyes. Thus if you watch, you will see that raptors often turn their whole head to adjust where they are looking and ascertain distance to prey. Raptors have the ability to rotate their heads quite a bit, with some owls able to turn their heads more than 180 degrees, looking completely backwards and then some.

Another feature of many raptors providing protection to their sensitive eyes is the existence of three eyelids; two outer ones that close up-and-down, and an inner translucent eyelid, called a nictating membrane, which opens and closes fore-and-aft. The nictating membrane may be closed while a raptor is digging its beak into its prey, to avoid getting things in its eyes, and the osprey is known to close the membrane before diving into water.

And then there are the vultures. Although their eyesight is not as keen as other raptors, their sense of smell is highly attuned. The Turkey Vultures in particular have very large nostrils without a septum (you can see right through their nose from one side of the head to the other), and very well developed olfactory bulb, giving them an exceptional sense of smell. Studies have shown that they are also selective in what they feed on based on smell, preferring prey 24 hours dead over older, “smellier” carcasses. Black Vultures, by contrast, cannot smell as well as Turkey Vultures, but here in Central Texas, they often watch where the Turkey Vultures are circling, and use their cousins to hone in on a prime piece of roadkill.

Basic Raptor External Anatomy

As with all types of birding, having a common language to describe parts of a raptor makes identification and communication much easier. For additional terminology, see our Bird Honor page.

1. Throat
2. Mandible (lower jaw)
3. Gape
4. Crown
5. Superciliary Ridge/Supraorbital Ridge
6. Nares (nostril)
7. Cere
8. Maxilla (upper jaw)
9. Tomial Tooth/Mandibular Tomial

Raptor Life: Food and Shelter

Feeding: Raptors are primarily carnivores or insectivores, eating small and medium-sized mammals, reptiles of all sorts, amphibians, other birds, fish, and various insects. Most raptors have their own preferences for food, and, as seen above, these may be reflected in the physical characteristics of their talons, beaks, and eyes. Our common Red-Shouldered Hawks like to eat small mammals, as well as snakes, toads, and the occasional small bird (I have seen one flying back to its nest with a baby bird from another bird’s nest to feed its young). Mississippi Kites snatch large insects off branches and grasses or out of the air with their talons, and may quickly transfer their catch into their mouth while flying. Osprey are fish eaters (and not much else), and can be seen carrying their slippery prey in their talons as they fly to a place to eat. Our Eastern Screech Owl eats small mammals and birds, but also earthworms, frogs, lizards, insects, and crawdads.

Nesting: Given the variety of raptors, there is no single nest type. Many of the larger diurnal raptors build stick nests on poles or high in trees, some coming back every year to the same nest. Bald Eagle Nests are massive, up to six feet in diameter and 2-4 feet deep, made of sticks woven together, and lined with feathers and lichens. They may add to their nest each year (some large multi-year bird nests have been used to trace changes in feeding patterns back through time, by seeing what remains are left in each layer). Burrowing Owls, as their name suggests, live in holes up to three feet or longer, often using a mammal burrow as a starting point. They may line these burrows with manure. American Kestrels (like many of our owls) are cavity nesters, usually using old woodpecker holes, but also willing to use manmade nesting boxes. Turkey Vultures don’t bother building nests, but instead just make a scrape in the soil, and may reuse this same site for years if undisturbed by people.

A comparison of the life span of some of our Central Texas raptors

Some Raptor Facts, with a few comparisons to other birds. For more bird facts, see our Bird Honor page.

The Small

The smallest diurnal raptors are the Black-Thighed Falconet and the White-Fronted Falconet, the former, found on peninsular Malaysia and southern Thailand, Borneo, Sumatra and Java, measures 14-17 centimeters (5.5-6.7 inches) and weighs 28-55 grams (0.06-0.12 pounds). The latter is found in northern Borneo, also measuring 14-17 centimeters (5.5-6.7 inches), weighing 35-65 grams (0.08-0.14 pounds).
The smallest diurnal raptor in the United States is the American Kestrel, which by comparison is a massive 22-31 centimeters (8.7-12.2 inches) long, and 80-165 grams (0.18-0.36 pounds).
The smallest nocturnal raptor is a toss-up (depending upon the individual specimen) between the Northern Pygmy Owl at 16-18 centimeters (6.3-7.1 inches long), found through Central America, Mexico, the western United States to Canada, and the Elf Owl, living in the American southwest and south central states and Mexico, at 13-30 centimeters (5.1-11.8 inches) long, and weighing around 40 grams (0.09 pounds).
By comparison, the Pygmy Parrots of New Guinea are the smallest parrots, measuring just 3.5-4 inches in length. The African Pygmy Goose, weighing in at just around six-tenths of a pound and measuring 12 inches in length, is the smallest of the waterfowl.

The Big

The largest diurnal raptor by wingspan is the Andean Condor, measuring in at 10 feet or more across. By weight, it is the California Condor, at 31 pounds.
The largest nocturnal raptor by weight is either the Eurasian Eagle-Owl, measuring 2-2.5 feet with a wingspan of 5-6 feet (weighing 3-9 pounds), or the endangered Blakiston’s Fish Owl, measuring 2-2.3 feet and weighing 6.5-10 pounds. By size (but not weight), the Great Grey Owl tops both, measuring 2-2.75 feet with a wingspan of up to five feet, but weighing in at only 1.3 to slightly over 4 pounds.
By comparison, the largest parrots, the Hyacinth Macaw, can reach a length of some 3.3 feet, and the flightless Kakapo can weigh up to 4.5 pounds, and the largest waterfowl are the Trumpeter Swan, with a 10 foot wingspan and weighing in at some 38 pounds.

The Haast Eagle, a massive extinct raptor of New Zealand

The extinct Haast Eagle (Hieraaetus moorei) of New Zealand was perhaps the largest of the raptors, with a wingspan of 8-10 feet, a body more than four and a half feet long, and weighing up to 40 pounds. Each claw was as much as 3.5 inches long, similar to those of a tiger. The Haast Eagle’s massive size was perfect for hunting their favorite prey, the massive flightless Moa. When the Moa went extinct (in part due to over hunting by people), the Haast Eagle no longer had prey, and went extinct as well.

Raptors of the Bible
There are many mentions of raptors in the Bible. Depending upon the version, there may be different translated names, but in general you will be able to find eagle, owl, falcon, kite, osprey, and vulture.

Eagles generally denote speed, power, strength and might, as well as something largely unreachable and untamable.

God's salvation is represented as a powerful eagle, protecting his people or carrying them out of trouble (Ex. 19:4, Deut. 32:11, Rev. 12:14, Ezek. 17:1-10)
The eagle may be a symbol of strength, youth and revival (Ps. 103:5, Is. 40:28-31)
Just as the eagle can be seen as powerful for good, it can also represent the power of destruction, often as either a tool of God’s wrath, or as a the power of an overwhelming enemy (Deut. 28:49, Jer. 4:13, Jer. 48:40, Jer. 49:22, Lam. 4:19, Hos. 8:1, Hab. 1:8)
Eagles are fast, and are used as a comparison to speed, or to things being snatched away or fleeting (2 Sam. 1:23, Job 9:26, Prov. 23:5)
The soaring height of eagles and their nests hidden in high rocky crags represents distance - a distance that is easily overcome by God (Jer. 49:16, Ob. 1:4)
Finally, eagles are often seen in the characteristics of heavenly beings (Ez. 1:10, Dan. 7:4, Rev. 4:7, Rev. 8:13 - some versions use eagle, others angel)

Owls represent something that lives in desolate places, in places without people. They are a symbol of complete destruction, or of severe loneliness (Job 30:29 - some versions use ostriches, Ps. 102:6, Is. 13:21, Is. 14:23 - some versions replace owl with porcupine, Is. 34:8-15, Jer. 50:39 - some versions use ostrich, Zeph. 2:14 - some versions translate as different birds)

There are other examples of raptors in the Bible, sometimes just as themselves (as in the discussions of clean and unclean animals in Leviticus and Deuteronomy), at other times based on their characteristics (falcons with strong sight, vultures gathering around a corpse).

The Raptor Honor Requirements
1. What does the word “raptor” mean?
2. Classification:
a. Identify the 2 major groups of raptors.
b. List the scientific names of the orders & families collectively referred to as "raptors" or "birds of prey."
c. Identify distinct characteristics of raptors.
d. an example of a raptor that illustrates each of the families represented under these two major groups (7 families).
3. From a diagram, identify or label the following parts of the raptor:
a. Eyes. b. Feet & Talons
c. Chest. d. Body
e. Beak. f. Ears
g. Wings. h. Feathers
4. Discover the following information about raptors. Use this information to compare and contrast raptors with another family of birds, such as ducks & geese (anatidae) or parrots (psittaciform).
a. the smallest diurnal and nocturnal raptor
b. the largest diurnal and nocturnal raptor
c. kinds of nests do raptors build
d. the average life span for large and small raptors
e. the most common food of raptors
f. How do raptors eat their food?
5. Do one of the following:
a. Watch a live raptor demonstration
b. Read a book on raptors
c. Watch a film documentary on raptors
6. Do two of the following:
a. Create a puppet show about raptors.
b. Dissect an Owl Pellet, preferably online, and write down what you find.
c. Make a chart of raptor wing spans and shapes of wings.
d. Make a file of at least 10 raptor craft ideas and complete 5 of the crafts.
e. Make a notebook, art display, media presentation or collage with pictures and information about raptors.
f. Create a board game about raptors.
g. Photograph at least 5 live raptors in the wild or captivity. Label your photographs.
7. Experience raptors in one of the following ways:
a. Visit a zoo or aviary. Have a docent tell you about the raptors they care for.
b. Have a specialist visit the group and share what he/she does with raptors.
8. Observe raptors in the wild nesting or migrating. If possible, work with an area nature center, park, or Wildlife Management Areas.
9. Find two Bible passages about raptors and summarize a moral lesson from each one.