Huge California Sea Lion Male Underwater, a bull, patrolling his breeding harem and territory, Coronado Islands, Mexico. His sagittal crest, the bony bump on his head that distinguishes adult male sea lions, is clearly seen. This particular sea lion bears an orange tag on his left foreflipper, probably as a result of rescue and release as a young sea lion years earlier.
Species: California sea lion, Zalophus californianus
Location: Coronado Islands (Islas Coronado), Baja California, Mexico
Image ID: 38657
The bisons massive head is its most characteristic feature. Its forehead bulges because of its convex-shaped frontal bone. Its shoulder hump, dwindling bowlike to the haunches, is supported by unusually long spinal vertebrae. Over powerful neck and shoulder muscles grows a great shaggy coat of curly brown fur, and over the head, like an immense hood, grows a shock of black hair. Its forequarters are higher and much heavier than its haunches. A mature bull stands about 6 1/2 feet (2 meters) at the shoulder and weighs more than 2,000 pounds (900 kilograms). The bisons horns are short and black. In the male they are thick at the base and taper abruptly to sharp points as they curve outward and upward; the females horns are more slender.
Species: American bison, Bison bison
Location: Yellowstone National Park, Wyoming
Image ID: 13120
Male elk bugling during the fall rut. Large male elk are known as bulls. Male elk have large antlers which are shed each year. Male elk engage in competitive mating behaviors during the rut, including posturing, antler wrestling and bugling, a loud series of screams which is intended to establish dominance over other males and attract females.
Species: Elk, Cervus canadensis
Location: Madison River, Yellowstone National Park, Wyoming
Image ID: 19697
Male elk bugling during the fall rut. Large male elk are known as bulls. Male elk have large antlers which are shed each year. Male elk engage in competitive mating behaviors during the rut, including posturing, antler wrestling and bugling, a loud series of screams which is intended to establish dominance over other males and attract females.
Species: Elk, Cervus canadensis
Location: Mammoth Hot Springs, Yellowstone National Park, Wyoming
Image ID: 19698
Elk, bull elk, adult male elk with large set of antlers. By September, this bull elk's antlers have reached their full size and the velvet has fallen off. This bull elk has sparred with other bulls for access to herds of females in estrous and ready to mate.
Species: Elk, Cervus canadensis
Location: Mammoth Hot Springs, Yellowstone National Park, Wyoming
Image ID: 19721