Late Cretaceous 90 million years ago. About four feet long and 25 pounds. Long, narrow snout; smooth teeth; probably feathers. Only the third raptor ever to be discovered in South America, Buiteraptor was on the small side, and the lack of serrations on its teeth indicate that it fed on much smaller animals, rather than ripping into the flesh of its fellow dinosaurs. As with other raptors, paleontologists have reconstructed Buitreraptor as covered with feathers, connoting its close evolutionary relationship to modern birds.
By the way, this dinosaur's odd name stems from the fact that it was unearthed, in , in the La Buitrera area of Patagonia—and since Buitrera is Spanish for "vulture," the moniker seemed appropriate! Early Cretaceous million years ago. About three feet long and 10 pounds. Four wings; long feathers. As is often the case when a brand-new dinosaur is discovered, there has been a lot of speculation about Changyuraptor, not all of which is warranted. Specifically, the media have been touting the hypothesis that this raptor—a relative of the much smaller, and also four-winged, Microraptor—was capable of powered flight.
While it's true that the tail feathers of Changyuraptor were a foot long, and may have served some navigational function, it may also be the case that they were strictly ornamental and only evolved as a sexually selected characteristic. Another clue that Changyuraptor's aerial bona-fides are being overstated is that this raptor was fairly large, about three feet from head to tail, which would render it much less airworthy than Microraptor after all, modern turkeys have feathers, too!
At the very least, though, Changyuraptor should shed new light on the process by which the feathered dinosaurs of the early Cretaceous period learned to fly. About three feet long and pounds. Long tail; feathers on front and hind limbs. True to the "crypto" in its name, Cryptovolans has occasioned its share of disputes among paleontologists , who aren't quite sure how to classify this early Cretaceous feathered dinosaur.
Some experts believe that Cryptovolans is actually a "junior synonym" of the better known Microraptor, a four-winged raptor that made a big splash in paleontology circles a couple of years ago, while others maintain that it deserves its own genus, mainly because of its longer-than-Microraptor tail. Adding to the mystery, one scientist insists that Cryptovolans not only merits its own genus but was more evolved toward the bird end of the dinosaur-bird spectrum than even Archaeopteryx —and thus should be considered a prehistoric bird rather than a feathered dinosaur!
The late Cretaceous Dakotaraptor is only the second raptor ever to be discovered in the Hell Creek formation; the type fossil of this dinosaur bears unmistakable "quill knobs" on its front limbs, meaning it almost certainly possessed winged forearms. See an in-depth profile of Dakotaraptor. The "Velociraptors" in Jurassic Park were actually modeled after the Deinonychus , a fierce, man-sized raptor distinguished by the huge claws on its back feet and its grasping hands—and that wasn't nearly as smart as it has been depicted in the movies.
Woodlands of northern Europe. About 10 feet long and pounds. Large head; curved claws on hind feet; probably feathers. The name Dromaeosauroides is quite a mouthful and has probably rendered this meat-eater less well-known to the public than it rightfully should be. Not only is this the only dinosaur ever to be discovered in Denmark a couple of fossilized teeth recovered from the Baltic Sea island of Bornholm , but it's also one of the earliest identified raptors, dating to the early Cretaceous period, million years ago.
As you may have guessed, the pound Dromaeosauroides was named in reference to the better-known Dromaeosaurus "running lizard" , which was much smaller and lived tens of millions of years later. Plains of North America. Late Cretaceous 75 million years ago.
About six feet long and 25 pounds. Small size; powerful jaws and teeth; probably feathers. Dromaeosaurus is the eponymous genus of dromaeosaurs, the smallish, speedy, bipedal, probably feather-covered dinosaurs better known to the general public as raptors. Still, this dinosaur differed from more famous raptors like Velociraptor in some important respects: the skull, jaws, and teeth of Dromaeosaurus were relatively robust, for instance, a very tyrannosaur-like trait for such a small animal.
Despite its standing among paleontologists, Dromaeosaurus Greek for "running lizard" isn't very well represented in the fossil record; all we know of this raptor amounts to a few scattered bones unearthed in Canada in the early 20th century, mostly under the supervision of the buccaneering fossil-hunter Barnum Brown.
Analysis of its fossils reveals that Dromaeosaurus was a more formidable dinosaur than Velociraptor: its bite may have been three times as powerful in terms of pounds per square inch and it preferred to disembowel its prey with its toothy snout, rather than the single, oversized claws on each of its hind feet. The recent discovery of a closely related raptor, Dakotaraptor, lends added weight to this "teeth first" theory; like Dromaeosaurus, this dinosaur's hind claws were relatively inflexible, and wouldn't have been of much use in close-quarters combat.
About three feet long and a few pounds. Small size; feathers; large, single claws on hind feet. Discovered in China's famous Liaoning fossil beds —the final resting place of a huge variety of small, feathered dinosaurs from the early Cretaceous period—Graciliraptor is one of the earliest and smallest raptors yet identified, measuring only about three feet long and weighing a couple of pounds soaking wet.
In fact, paleontologists speculate that Graciliraptor occupied a position close to the "last common ancestor" of raptors, troodontids feathered dinosaurs closely related to Troodon , and the first true birds of the Mesozoic Era, which probably evolved around this time.
Though it's unclear whether it was similarly equipped, Graciliraptor also seems to have been closely related to the famous, four-winged Microraptor, which arrived on the scene a few million years later. Long legs and tail; bipedal posture; probably feathers. The amazingly well-preserved fossil of Linheraptor was discovered during an expedition to the Linhe region of Mongolia in , and two years of preparation have revealed a sleek, probably feathered raptor that prowled the plains and woodlands of late Cretaceous central Asia in search of food.
Comparisons to another Mongolian dromaeosaur, Velociraptor, are inevitable, but one of the authors of the paper announcing Linheraptor says it's best compared to the equally obscure Tsaagan yet another, similar raptor, Mahakala, has been found in these same fossil beds. About feet long and pounds. Small size; bipedal posture; probably feathers. As obscure as it is, the tiny, probably feathered Luanchuanraptor occupies an important place in the dinosaur record books: it was the first Asian raptor to be discovered in eastern rather than northeastern China most dromaeosaurs from this part of the world, like Velociraptor, lived further west, in modern-day Mongolia.
Other than that, Luanchuanraptor seems to have been a fairly typical " dino-bird " for its time and place, possibly hunting in packs to overwhelm the bigger dinosaurs that counted as its prey. Like other feathered dinosaurs, Luanchuanraptor occupied an intermediate branch on the tree of bird evolution.
Microraptor fits uneasily into the raptor family tree. This tiny dinosaur had wings on both its front and back limbs, but it probably wasn't capable of powered flight: rather, paleontologists picture it gliding like a flying squirrel from tree to tree. About six feet long and 50 pounds.
Large size; bipedal posture; feathers. If only the paleontologists who discovered it had gotten their act together, Neuquenraptor might stand today as the first identified raptor from South America.
Unfortunately, this feathered dinosaur's thunder wound up being stolen by Unenlagia, which was discovered in Argentina a few months later but, thanks to a canny bit of analytical work, named first. Today, the weight of the evidence is that Neuquenraptor was actually a species or specimen of Unenlagia, characterized by its unusually large size and its propensity for flapping its arms but not actually flying.
Woodlands of western Europe. About six feet long and pounds. Small size; bipedal posture; possibly feathers. As problematic genera go, Nuthetes has proven a tough nut to crack. It took over a decade after its discovery in the midth century for this dinosaur to be classified as a theropod. The question was exactly what kind of theropod: was Nuthetes a close relative of Proceratosaurus, an ancient forebear of Tyrannosaurus Rex , or a Velociraptor-like dromaeosaur?
Owls are typically nocturnal predators, relying on their excellent vision and hearing to catch food. Some owls have tufts of feathers on the tops of their head, often called horns or ears. They are not really horns or ears but are thought to serve as camouflage or behavioral signaling devices. Owls have large asymmetrical ear holes located behind the eyes on each side of the face, underneath their feathers which aid in hearing and flight direction to catch prey. Each ear catches sound at a different time allowing for pinpoint accuracy of prey location.
The round face and facial disks of feathers around the eyes also help in hearing and funneling light to increase visibility. Owls have binocular vision.
Their eyes are fixed in sockets so they are only able to see what is in front of them. To see the things around them, owls must use the added bones in their neck 14 total to rotate their head. Owls have four toes; a permanent back toe and three front toes, one of which when the feet are spread wide apart is capable of rotating to the front or back to improve their grip on prey once captured.
Most owls have feathers down to their sharp toenails unlike most birds of prey. It's believed to help keep them warm and protect from prey bites. Owls have soft-edged flight feathers that allow them to fly almost silently; the flight feathers of an owl are slightly spaced to allow air to move around and through them when flying which helps to keep noise down. An owl's diet consists of rodents and small mammals.
Their digestive system makes use of the nutritious portions of the prey, and the undigested parts hair, bones, claws, teeth, etc. Worldwide there are over species of meat-eating birds that comprise the order Falconiformes, the scientific name for hawk. Some hawk species undertake long migration journeys, traveling thousands of miles each year - a testimony to their strength and stamina. Hawks have excellent hearing and eyesight. Their vision is 8 times greater than that of a human! In our region, hawks typically breed in early spring, and many will pair for life, unless a mate is lost to death.
Eagles are large bodied raptors, mostly dark brown in color with long, broad wings, and fan-shaped tails and have large, strong feet and a powerful beak. There are 2 species of eagles widespread throughout North America, the bald eagle and the golden eagle; both can be observed in our region! The bald eagle is America's national symbol — has been since — and is unique to North America!
The average wingspan of an eagle can vary from six to seven feet! That's a BIG bird! The mature bald eagle appears very different than its relative the golden eagle in color; it has a distinctive white head and tail, and a bright yellow beak. These distinguishing bald eagle traits do not appear until the bird reaches adulthood when they are three to four years old.
Bald eagles usually live near water oceans, rivers, lakes , while golden eagles live in open, mountainous country. There are 10 species of harriers worldwide but only 1 species in North America, the northern harrier also known as the "marsh hawk". The Caracara has blunt-tipped wings, a long tail, bright facial skin, and inhabits a restricted southern range.
They feed on carrion, and are often seen with vultures. Eagles are large in size up to 15 lbs. They have long wings up to a 7 ft. Studies have shown that migrant eagles can travel long distances in a single day using minimal energy. Eagles can hunt a variety of prey; Bald Eagles often scavenge carcasses or steal prey from other raptors throughout the year, but they are exceptional at catching fish on their own, plucking them from the water's surface with a quick swipe.
They have also been seen snatching blackbirds from a marsh, or chasing down ducks in direct flight. The bill of a Bald Eagle is prominent, and powerful enough to break the skin of even the largest salmon! The Golden Eagle hunts primarily mammals and large birds, but is adept at catching snakes and whatever prey catches their eye; sometimes animals as large as baby deer are part of their diet!
Golden Eagles are able to stoop at speeds that rival the Peregrine Falcon! Eagles are mostly dark in color, attaining adult appearance in 4 to 5 years. The Osprey is a large, fish-eating raptor of inland lakes, rivers, and waterways, that can be seen fishing along ocean beaches at times. They are very active hunters and exciting to watch as they hover and dive into the water repeatedly until they come up with a fish. They have sharply curved talons and small spines called spicules on the pads of their feet that are perfectly adapted to holding onto slippery fish.
Ospreys can sometimes be seen carrying fish far from water during migration — a phenomenon birders refer to as "packing a lunch. They attain their adult appearance during their second year. The Northern Harrier occurs only in North America. They are easy to identify, and often easy to observe, but are unique in many ways.
Harriers have long, narrow wings, a long tail, and a brilliant white rump that often clinches its ID. They also have a unique, owl-like facial pattern made up of stiff feathers that form a 'facial disk'. This helps them to hunt by sound as much as sight, sometimes in near complete darkness. Harriers are fun to watch in flight, as they buoyantly teeter side-to-side over marshes and fields in search of mice and voles.
Harriers perch on the ground or on low posts, unlike most raptors that perch in trees or higher surfaces. Harriers attain an adult appearance in their second year, when males and females are markedly different. Kites are a diverse, lesser known, group of raptors that reside in warmer climate territories.
Mississippi and Swallow-tailed Kite in particular are masterful fliers, able to "float" in the air with ease even on windless days. They twist and turn with a slight move of the tail or wings, and their ability to catch small prey on the wing is unmatched.
The other two North American kites, Snail Kite and especially Hook-billed Kite, have paddle-shaped wings and eat mostly snails. Most kites attain adult appearance in years. Since most owl species are nocturnal active at night and difficult to see, they are thought of as mysterious and regarded with superstition. Most people are taught that seeing an owl will potentially bring bad luck.
However, that is far from the truth -- seeing an owl is one of the most exhilarating experiences in bird watching.
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