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The zebra mussel (Dreissena polymorpha) is a small, non-native mussel originally found in Russia. In 1988, this animal was transported to North America in the ballast water of a transatlantic freighter and colonized parts of Lake St. Clair. In less than ten years, zebra mussels spread to all five Great Lakes.
The zebra mussel (Dreissena polymorpha) is a small, non-native mussel originally found in Russia. In 1988, this animal was transported to North America in the ballast water of a transatlantic freighter and colonized parts of Lake St. Clair. In less than ten years, zebra mussels spread to all five Great Lakes.
Dryland agriculture in the Northwestern Great Plains ecoregion.
Dryland agriculture in the Northwestern Great Plains ecoregion.
Male ruddy duck swimming in water.
Male ruddy duck swimming in water.
Female ruddy duck swimming in water.
Female ruddy duck swimming in water.
Mergansers swimming in water.
Hooded Merganser (Lophodytes cucullatus).
Hooded Merganser (Lophodytes cucullatus).
Monarch butterfly on dense blazing star.
Monarch butterfly on dense blazing star.
Image of the butterflies Danaus plexippus on the purple flowers of Liatris spicata.
Image of the butterflies Danaus plexippus on the purple flowers of Liatris spicata.
Rice Paper Butterfly on leaf.
Rice Paper Butterfly on leaf
Shining coneflower in Botanical Gardens.
Shining coneflower in Botanical Gardens.
Purple coneflower.
Monarch butterfly on a dense blazing star.
Monarch butterfly on a dense blazing star.
Monarch butterfly on dense blazing star.
Monarch butterfly on dense blazing star.
Image of the butterflies Danaus plexippus on the purple flowers of Liatris spicata.
Image of the butterflies Danaus plexippus on the purple flowers of Liatris spicata.
Tropical waterlily.
The world-famous Delicate Arch was formed by the movement of underground salt beds beneath overlying sandstone, in concert with surface events including water, ice, and erosion, which washed away or broke off the sandstone to create the arches and fins found throughout Arches National Park.
The world-famous Delicate Arch was formed by the movement of underground salt beds beneath overlying sandstone, in concert with surface events including water, ice, and erosion, which washed away or broke off the sandstone to create the arches and fins found throughout Arches National Park.
White-tailed deer tracks in the mud.
White-tailed deer tracks in the mud.
Area of burned trees from a 2002 wildfire, caused by a lightning strike, at Mesa Verde National Park.
Area of burned trees from a 2002 wildfire, caused by a lightning strike, at Mesa Verde National Park.
Raccoon paw print in mud.
Raccoon paw print in mud.
Cape Sable seaside sparrow. Credit: Lori Oberhofer, National Park Service.
Cape Sable seaside sparrow. Credit: Lori Oberhofer, National Park Service.