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: 19693
A rainbow appears in the mist of the Lower Falls of the Yellowstone River. At 308 feet, the Lower Falls of the Yellowstone River is the tallest fall in the park. This view is from Lookout Point on the North side of the Grand Canyon of the Yellowstone. When conditions are perfect in midsummer, a midmorning rainbow briefly appears in the falls.
Location: Grand Canyon of the Yellowstone, Yellowstone National Park, Wyoming
Image ID: 13319
Grand Prismatic Spring (left) and Excelsior Geyser (right). Grand Prismatic Spring displays a stunning rainbow of colors created by species of thermophilac (heat-loving) bacteria that thrive in narrow temperature ranges. The blue water in the center is too hot to support any bacterial life, while the outer orange rings are the coolest water. Grand Prismatic Spring is the largest spring in the United States and the third-largest in the world. Midway Geyser Basin.
Location: Midway Geyser Basin, Yellowstone National Park, Wyoming
Image ID: 13571
Old Faithful geyser, sunrise. Reaching up to 185' in height and lasting up to 5 minutes, Old Faithful geyser is the most famous geyser in the world and the first geyser in Yellowstone to be named.
Location: Upper Geyser Basin, Yellowstone National Park, Wyoming
Image ID: 26939
Townsley Lake (10396'), a beautiful alpine lake sitting below blue sky, clouds and Fletcher Peak (right), lies amid the Cathedral Range of glacier-sculpted granite peaks in Yosemite's high country, near Vogelsang High Sierra Camp.
Location: Yosemite National Park, California
Image ID: 23206
White southern right whale calf underwater, Eubalaena australis. About five per cent of southern right whales are born white due to a condition known as grey morphism and will gradually turn dark as they age. They are not albino (which is a complete lack of pigmentation). Sometimes referred to as "brindled", the white coloration is a recessive genetic trait and only lasts a few months. Typically, but not always, white calves will become much darker as they mature but will still somewhat lighter than normal even as adults.
Species: Southern Right Whale, Eubalaena australis
Location: Puerto Piramides, Chubut, Argentina
Image ID: 35908