The word raptor comes from the Latin rapere, which mean to seize or plunder — an apt way to describe birds that swoop down on their prey.

All raptors have a hooked beak, strong feet with sharp talons, keen eyesight, and a carnivorous diet.

Hooked beak — The raptor's beak sets it apart from other birds. All raptors have the same beak design, curved at the tip with sharp cutting edges to rip and tear apart their prey. Falcons use their beak to kill their prey by severing the spinal cord.
Sharp talons — Birds of prey have powerful leg and toe muscles that end with sharp talons. This makes their feet lethal weapons. Their feet are perfectly designed to catch, hold, and carry prey. The length and size of a raptors toes, and the curvature and thickness of its talons are related to the type of prey it pursues. Most birds of prey have three toes pointing forward and one pointing backward. These toes can apply an extremely powerful grip on their prey, literally crushing it to death. The talons may also kill the prey by piercing the soft tissue and vital organs. Osprey, like owls, have one hinged toe that can be held in a forward or back position. This allows them to hold fish with two talons on each side for a secure grip. Osprey also have spiny scales on their feet that help them hold slippery fish more securely.
Keen eyesight — Raptors have very keen eyesight due to the relative size of the eyeball in proportion to their head, eye muscles designed for rapid focus, and the high resolution of the retina. Diurnal raptors have full color vision and two concentrations of sharp vision on the retina. This sharpest point of vision is called the fovea. When the raptor’s two fovea work in unison, they give them very accurate depth perception which aids catching moving objects. Nocturnal raptors, like owls, have an added advantage of remarkable night vision. Owls have a concentration of rods in their retina that are used to see in low light conditions. An owl's eyes are also located in the front of their heads, much like humans, giving them a larger area of binocular vision.
Carnivorous diet — Although the diet varies from species to species, all raptors are meat eaters.

Eye Placement in Animals

"Eyes in the front, the animal hunts. Eyes on the side, the animal hides."


Eye Placement for Predators
Eyes in the front of the head provide binocular vision and excellent depth perception. Most predators, whether birds or mammals, have eyes in the front of the head, allowing them to stalk and chase fleeing prey.

Drawbacks to Front-Facing Eyes
Animals with eyes in the front of the head have large blind spots and limited peripheral vision, making it easy to sneak up behind them.

Eye Placement for Prey Animals
Deer watch for predators while grazing.
An animal with eyes in the side of its head has a wide range of vision. Most herbivorous prey animals have eyes in the side of their heads, allowing them to see predators on all sides while grazing.

Drawbacks to Side-Facing Eyes
Rabbits probably have a blind spot directly in front of their noses. (sorry Bunnie)
Eyes in the side of the head often create a blind spot directly in front of the animal. A good sense of smell helps to overcome this handicap. Depth perception is poor.

Animal Examples
Placement of human eyes enable them to be good hunters.
Predators with forward-facing eyes include wolves, cats, humans, hawks and owls. Prey animals with side-facing eyes include deer, rabbits, rodents and most small birds.

Other Eye Locations
Crocodiles and alligators have eyes on top of the head, allowing them to stalk prey while keeping their bodies submerged and hidden.


Here are a few of the links I read info from:
http://www.gsseser.com/PDF/Coloring/Eye%20Placement.pdf
http://www.skullsunlimited.com/record_education.php?id=3
http://tinyurl.com/a2blgk3
http://www.newton.dep.anl.gov/natbltn/400-499/nb403.htm

Ask Audubon Do birds perspire?

Ray Tillmann, Menard, Illinois

Technically, only animals with sweat glands can sweat. Birds lack them, but being warm-blooded, they still must have some way to cool down when it's sweltering outside or they risk meltdown. Short of switching on a fan--which, incidentally, domesticated pigeons can be trained to do--they accomplish this by means of a number of thermoregulating strategies. Primarily, birds off-load excess heat either by evaporative cooling directly through the skin or by panting. The latter method cools the bird's airways and helps lower an elevated internal temperature. A robin running across a lawn on a sunny afternoon with its beak agape is doing exactly that. To supplement panting, several species vibrate the muscles and bones in their throats, a tactic called gular fluttering.

Bathing also beats the heat, as does ruffling feathers, seeking shade, and taking a siesta. Cormorants chill by perching with wings outspread. Other species, like black kites, ascend on thermals to reach higher, colder altitudes. Laysan albatrosses simply lean back to expose their feet to the breeze. Perhaps the most unique heat-dissipating antic belongs to some storks and New World vultures, which deliberately defecate on their legs. When the wind blows--voila!--natural air-conditioning. It's messy, but, hey, it does the trick--no sweat.

The leader of an owling walk told me that the night vision of humans and owls is comparable. True?

Bonnie Campbell, Kalamazoo, Michigan

Unless you can spot a vole more than a football field away, your night vision is as similar to an owl's as, well, night is to day. Once the sun sets, it's no contest. In truth, no creature can see in total darkness. But owls have a keen sense of sight in dim light, which, coupled with an acute sense of hearing, makes them superb nighttime hunters. The ancient Greeks believed the birds' extraordinary vision emanated from a magical inner light. Superstitions notwithstanding, owls are endowed with ophthalmic assets befitting their lofty position on the food chain. They possess gigantic eyeballs, which can better absorb low-level ambient light (if our eyes were proportionate, they would be as big as grapefruits!). Complementing each super-size orb is a powerful lens, a broad retina, and a pupil capable of dilating to a great diameter to collect photons under even the duskiest conditions. Like other vertebrates, owls have two types of sensory cells in their retinas: light-sensitive rods and color-sensitive cones. Their retinas are densely packed with rods, at the expense of cones. Thus, they can better distinguish small moving objects--albeit, probably in monochrome--while flying beneath the crepuscular canopy of a forest. Some owl species boast nearly a million rods per square millimeter (people have about 200,000 per square millimeter). Furthermore, owl eyes contain a tapetum, a mirror-like membrane that amplifies light and gives rise to eye shine, the phenomenon that causes your car's headlights to reflect off of animals' eyes after dark. The birds' sharp audiovisual system works in concert with silent flight and spatial memory to keep them from being among those creatures that go bump in the night.

By Carolyn Shea
Audubon Magazine

Barred owlets chirping from inside the eggs.

I was watching Cornell RT chat and copied some interesting info on how and why the shell thins for hatch. I didn't get all of it because that chat zooms by like crazy right now.
The mod was explaining how the chick inside the egg makes the first little hole with it's egg tooth and that's it's first gulp of fresh air. It keeps it's beak close to the hole it made to keep getting that fresh air to breathe. I took it to mean that is what makes the pip get bigger and bigger and eventually makes the egg shell break in half. Not so much the desire to "get out" as the desire to get air. ??? How would it know it wants "out" because it doesn't know it's "in"? It's instinct to breathe and keep that beak close to the hole results in the unzipping of the shell because of the position of the egg tooth? That's my take on it anyway and it's entirely possible that I'm wrong. LOL

Here's what I copied from the Mod at Cornell RT.
11:14 AM CulleyL: It will continue the break all the way around the egg until it can push the top off and escape. This is called breakup.
11:14 AM CulleyL: Along with oxygen absorption, CO2 is exhausted, forming carbonic acid in eggshell and weakens it. The egg shell is much thinner and weaker than when laid, by carbonic acid erosion from eyas' CO2
11:14 AM CulleyL: The embryo also absorbs some of the calcium from the shell during development which also weakens the shell
11:15 AM CulleyL: The hatching process from pip to out of the egg can take anywhere from 12-ish to 72 hours from start to finish.

How Bird Wings Work.


*Holey Moley! I was checking out the new pics in the gallery and noticed Hiker got a pic of Chicka's wing feathers open on the backstroke! Nice work Hiker.

Eagles in the Snow - Secret Japan - BBC Earth

I had just gotten over feeling like ticks were crawling in my head after finding one on my sister's dog's ear and now I've ran across this. This has set me back and now my head is itching again.

Avian Parasites
On May 22, 2013, the falcon eggs at Xcel Energy's Blackdog nest box began hatching. Immature female 16/U laid four eggs and hatched three. Although both parents diligently cared for their young, they never seemed to thrive. On May 27th, a watcher reporter strange black patches on one of the young. By May 31, two of the three young were dead. We don't know how the first one was disposed of, but the parents fed the second young to the third.

In watching the box, we noticed the strange black patches. We also saw that the remaining baby didn't seem to be developing properly. It was quite small for ten days of age, spent more time under its mother than might be expected, and didn't seem to be developing feathers properly. Perhaps the young falcon had Frounce, a yeast infection of the digestive tract that interferes with food intake. We decided to go up the stack and treat it with Spartrix. This has been a very hard year on our falcons and we really didn't want to lose any more.

I called Dan, our contact at the plant, and made the necessary arrangements. The Blackdog nest isn't especially easy to get to, since it is at the 600' level of the plant's smokestack. An elevator takes you to the 300' level and ladders take you the rest of the way. All told, you need to plan on a minimum of 50 minutes to visit the box. A big thanks to Dan for taking the time out of his day!

I was really shocked when we finally got to the nest. The falcon was very small, coated with black gunk, and swarming with parasites. They were on its back, belly, under wings, and neck. We thought the black gunk might be prey remains, but it was actually scabs, dried blood, and damaged feathers. The parasites, probably Amblycera or Hippoboscidae, were feeding by chewing soft areas of skin, causing an area of localized bleeding from which they drank.

I decided to give the young falcon Spartrix just in case (Frounce could easily kill a falcon this stressed), and then Dan held the falcon while I carefully cleaned it off.

This is a closeup of the falcon's back and neck. The parasites caused extensive damage, destroying feathers, interfering with feather growth, and delaying development. I killed and swabbed and crushed and killed and swabbed and crushed again. Once the parasites seemed to be (mostly) dead, I checked the box for anything that might be harboring more, took a few bits out, and returned the baby falcon, along with a dead quail. Mom was back in the box before we were back in the stack, and the quail was gone by the time we reached the bottom. Despite the damage, the young falcon had a good crop and even seemed somewhat feisty, weakly footing with tiny talons. While I don't know that the falcon will survive, we increased its chances of survival.

The parents have been very busy preening the young falcon, sometimes what seemed (to human watchers) rather roughly. We now know that they were trying to remove parasites. But where did the parasites come from? Since lice are transmitted by direct contact, I'm guessing that the lice were brought in on a prey item. According to Science Direct: "With no wings and very small eyes, chewing lice are, by and large, helpless away from their host." However, they were presumably able to hop, skittle, or jump from prey on to the young birds, who lack the armoring feathers of adults and weren't yet preening themselves. We'll be watching this box closely over the next couple of days to see what happens to the young bird.

Ever feel like a tick was crawling on you? Hours later, and I can still feel the lice crawling...
Posted 3 days ago by Amy Ries
http://raptorresource.blogspot.com/?view=classic

IR Reflective Feathers and Facial Disk - Amy Ries from RRP Blog

While creating owl highlights this morning for our Eaglecrest site, I came across some very close-up footage of a fledgling owl's face. As the capture above shows, the young owl has a lovely ring of IR reflective feathers around its facial disk. I was curious, so I did a little research. If owls can't see IR light, why would they have IR reflective feathers? Although I wasn't able to find much on IR and feathers, it seems most likely that the ring is produced by melanin, which fluoresces under IR light. Melanin not only produces colors ranging from dark black to reddish brown and pale yellow, it also makes feathers stronger, stiffer, and more resistant to wear.

While many birds have some amount of melanin in their feathers, especially stiff wing primaries, owls instead have porphyrin, a pigment that doesn't stiffen feathers. Soft, serrated feathers aid an owl's silent flight by breaking up turbulence. An angry peregrine falcon whooshes by you, but you won't hear an owl coming (cue creepy music here). Owls are the only birds known to use porphyrin in their wing feathers.

The rigidity of a material also impacts the way it reflects sound. Rigid materials reflect sound better and more quickly than softer ones. To quote: "The speed of sound in a medium is determined by a combination of the medium’s rigidity and its density. The more rigid the medium, the faster the speed of sound." A wall or canyon might produce an echo, but a pillow won't. I tried it myself, just to make sure.

So soft feathers are wonderful for silent flight, but they don't reflect sound nearly as well as rigid feathers. I am speculating that our little barn owl has a ring of stiff, melanin-producing feathers around its facial disk. The stiff feathers channel sound better and more quickly than soft ones would - absolutely crucial for an animal that hunts in little or no light. The contrast between the owl's porphyrin and melanin laden feathers produces a ring effect that might not be noticeable in a bird with more melanin. It is interesting to speculate that 'echoes' produced by the irregularly shaped ring might also aid directional hearing. Changes in the speed of sound might help owls gauge prey distance and location much as bats use echolocation (aside: this might be the most hilarious video about echolocation ever made).


We know that an owl's facial disk is special in many ways, and that barn owls in particular seem to be well-adapted for low to no-light hunting. This looks like another example of owl adaptation in action.

Deadliest Air Predators

African Goshawk
Smithsonian video - Speed Kills - Ultimate Precision at Top Speed

Kestrel hovering and hunting.

You will not want to miss Smithsonian's "Goshawk: Soul of the Wind." It follows the Northern goshawk through a season, and, even though the narrator gets male & female mixed up sometimes, it is a really good documentary with beautiful video. The showings are mostly during the day, but I taped it and watched. Don't miss it!

http://www.smithsonianchannel.com/sc/web...oul-of-the-wind

Osprey Talon Development

Do Birds get Tired of Flying? - Zoo La La (Ep 35) - Earth Unplugged

Cloacal Kiss in an Owl - Karla Bloem
Published on Jul 15, 2013

The "cloacal kiss" is how sperm is transferred from a male bird to a female bird. The cloaca is the one and only "out door" on a bird, so it's for eggs, poop, and sperm transfer. The male and female cloacae need to touch for the sperm to be transferred, and it's been called the "cloacal kiss." In this video, Alice the Great Horned Owl, a human imprinted owl used in educational programs, is responding to a human "mating" with her by putting a hand on her back. (The male owl lands on the females back to mate and transfer sperm.) You can see that when stimulated this way, her cloaca makes a kissing motion.