• View of Grand Canyon National Park at sunset from the South Rim

    Grand Canyon

    National Park Arizona

There are park alerts in effect.
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  • Warm Days and Cool Nights through Friday

    Expect breezy southwest winds this weekend as a cold front moves towards the region. More »

  • Bat Tests Positive for Rabies in Grand Canyon National Park

    Public Health Alert, October 2014: A bat recently removed from an area along the Colorado River within Grand Canyon National Park has tested positive for rabies. Any persons having physical contact with bats in the park, please follow this link. More »

New Zealand Mudsnail

New Zealand Mudsnail shell, Florida Caribbean Science Center

New Zealand Mudsnail

FL Caribbean Science Center

The New Zealand mudsnail, Potamopyrgus antipodarum was first discovered in the Snake River, Idaho in the 1980's. It is now rapidly spreading throughout the western US and has become established in rivers in seven western states and three national parks. It was discovered in the tailwaters below Glen Canyon Dam in March 2002. Subsequent searches in Grand Canyon found it distributed more than 225 miles downstream from the dam, so it was likely introduced several years earlier. Mudsnail populations often reaches densities greater than 100,000 per square meter in suitable habitat, and the species is associated with alterations in primary production and decreases in native invertebrate populations in rivers that it has invaded. Biologists are concerned about potential impacts it may have on native species, fisheries, and aquatic ecosystems in the western US.

Did You Know?

GRAND CANYON ROCKS

The more recent Kaibab limestone caprock, on the rims of the Grand Canyon, formed 270 million years ago. In contrast, the oldest rocks within the Inner Gorge at the bottom of Grand Canyon date to 1.84 billion years ago. Geologists currently estimate the age of Earth at 4.5 billion years.