 |
 |
 |
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.
Image ID: 19693
Species: Elk, Cervus canadensis
Location: Mammoth Hot Springs, Yellowstone National Park, Wyoming, USA | Bull elk spar to establish harems of females, Gibbon Meadow.
Image ID: 13151
Species: Elk, Cervus canadensis
Location: Gibbon Meadows, Yellowstone National Park, Wyoming, USA | Full grown, mature male coastal brown bear boar (grizzly bear) in sedge grass meadows.
Image ID: 19134
Species: Brown bear, Ursus arctos
Location: Lake Clark National Park, Alaska, USA |
 |
 |
 |
Adams River sockeye salmon. A female sockeye salmon swims upstream in the Adams River to spawn, having traveled hundreds of miles upstream from the ocean.
Image ID: 26161
Species: Sockeye salmon, Oncorhynchus nerka
Location: Adams River, Roderick Haig-Brown Provincial Park, British Columbia, Canada | Northern cardinal, male.
Image ID: 22891
Species: Northern cardinal, Cardinalis cardinalis
Location: Amado, Arizona, USA | Bull elephant seal exits the water to retake his position on the beach. He shows considerable scarring on his chest and proboscis from many winters fighting other males for territory and rights to a harem of females. Sandy beach rookery, winter, Central California.
Image ID: 15458
Species: Elephant seal, Mirounga angustirostris
Location: Piedras Blancas, San Simeon, California, USA |
 |
 |
 |
Magnificent frigatebird, adult male on nest, with throat pouch inflated, a courtship display to attract females.
Image ID: 16725
Species: Magnificent frigatebird, Fregata magnificens
Location: North Seymour Island, Galapagos Islands, Ecuador | Steller sea lions (Northern sea lions) gather on rocks. Steller sea lions are the largest members of the Otariid (eared seal) family. Males can weigh up to 2400 lb., females up to 770 lb.
Image ID: 16977
Species: Steller sea lion, Eumetopias jubatus
Location: Chiswell Islands, Kenai Fjords National Park, Alaska, USA | Magnificent frigatebird, adult female on nest.
Image ID: 16726
Species: Magnificent frigatebird, Fregata magnificens
Location: North Seymour Island, Galapagos Islands, Ecuador |
 |
 |
 |
Black bear walking in a grassy meadow. Black bears can live 25 years or more, and range in color from deepest black to chocolate and cinnamon brown. Adult males typically weigh up to 600 pounds. Adult females weight up to 400 pounds and reach sexual maturity at 3 or 4 years of age. Adults stand about 3' tall at the shoulder.
Image ID: 18744
Species: American black bear, Ursus americanus
Location: Orr, Minnesota, USA | Sea lions underwater, adult male (left) and female (right).
Image ID: 31218
Species: California sea lion, Zalophus californianus
Location: Sea of Cortez, Baja California, Mexico | Sea lion harem of females, underwater.
Image ID: 31228
Species: California sea lion, Zalophus californianus
Location: Sea of Cortez, Baja California, Mexico |
 |
 |
 |
Adult male humpback whale singing, suspended motionless underwater. Only male humpbacks have been observed singing. All humpbacks in the North Pacific sing the same whale song each year, and the song changes slightly from one year to the next.
Image ID: 02796
Species: Humpback whale, Megaptera novaeangliae
Location: Maui, Hawaii, USA | Humpback whale mother, calf (top), male escort (rear), underwater. A young humpback calf typically swims alongside or above its mother, and male escorts will usually travel behind the mother.
Image ID: 02819
Species: Humpback whale, Megaptera novaeangliae
Location: Maui, Hawaii, USA | Adult male humpback whale bubble streaming underwater. The male escort humpback whale seen here is emitting a curtain of bubbles as it swims behind a female (left) during a competitive group. The bubble curtain may be meant as warning or visual obstruction to other male whales interested in the mother.
Image ID: 02828
Species: Humpback whale, Megaptera novaeangliae
Location: Maui, Hawaii, USA |
 |
 |
 |
Adult male humpback whale bubble streaming underwater. The male escort humpback whale seen here is emitting a curtain of bubbles as it swims behind a mother and calf. The bubble curtain may be meant as warning or visual obstruction to other nearby male whales interested in the mother.
Image ID: 05925
Species: Humpback whale, Megaptera novaeangliae
Location: Maui, Hawaii, USA | North Pacific humpback whale, escort in competitive group makes fast close pass.
Image ID: 06057
Species: Humpback whale, Megaptera novaeangliae
Location: Maui, Hawaii, USA | Pyrrhuloxia, male.
Image ID: 22894
Species: Pyrrhuloxia, Cardinalis sinuatus
Location: Amado, Arizona, USA |
 |
 |
 |
Bullock's oriole, first year male.
Image ID: 22895
Species: Bullock's oriole, Icterus bullockii
Location: Amado, Arizona, USA | Northern cardinal, female.
Image ID: 22897
Species: Northern cardinal, Cardinalis cardinalis
Location: Amado, Arizona, USA | Acorn woodpecker, female.
Image ID: 22906
Species: Acorn woodpecker, Melanerpes formicivorus
Location: Madera Canyon Recreation Area, Green Valley, Arizona, USA |
 |
 |
 |
Black-headed grosbeak, male.
Image ID: 22911
Species: Black-headed grosbeak, Pheucticus melanocephalus
Location: Madera Canyon Recreation Area, Green Valley, Arizona, USA | Brown-headed cowbird, male.
Image ID: 22916
Species: Brown-headed cowbird, Molothrus ater
Location: Amado, Arizona, USA | House finch, male.
Image ID: 22927
Species: House finch, Carpodacus mexicanus
Location: Amado, Arizona, USA |
 |
 |
 |
Hooded oriole, female.
Image ID: 22944
Species: Hooded oriole, Icterus cucullatus
Location: Amado, Arizona, USA | House sparrow, breeding male.
Image ID: 22945
Species: House sparrow, Passer domesticus
Location: Amado, Arizona, USA | Adult female moose in deep meadow grass near Christian Creek.
Image ID: 13039
Species: Moose, Alces alces
Location: Christian Creek, Grand Teton National Park, Wyoming, USA |
 |
 |
 |
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.
Image ID: 13120
Species: American bison, Bison bison
Location: Yellowstone National Park, Wyoming, USA | Wood duck, male.
Image ID: 15694
Species: Wood duck, Aix sponsa
Location: Santee Lakes, California, USA | Black bear walking in a grassy meadow. Black bears can live 25 years or more, and range in color from deepest black to chocolate and cinnamon brown. Adult males typically weigh up to 600 pounds. Adult females weight up to 400 pounds and reach sexual maturity at 3 or 4 years of age. Adults stand about 3' tall at the shoulder.
Image ID: 18741
Species: American black bear, Ursus americanus
Location: Orr, Minnesota, USA |
|