Images

September 18, 2010. Colorado River, Grand Canyon, River Mile 52.8, Nankoweap, Downstream View from River Right. Riparian vegetation continues to increase along the river, reducing the amount of sand that is visible at this distance. There has been a slight increase in the amount of mesquite, but overall it appears to be similar to that present 19 years before.

September 18, 2010: Colorado River, Grand Canyon, River Mile 52.8, Nankoweap Creek, Downstream View from River Right. Sandbars continue to decrease in exposed area owing to erosion and establishment of vegetation, both native mesquite and non-native tamarisk.

Aerial view of the study area in Canyonlands National Park.

Repeat photograph of Saguaro National Monument (now Saguaro National Park) East, Rincon Mountain District. This photo was taken in 2010 by Dr. Ray Turner, USGS and is a match of a 1935 photograph taken by the National Park Service (NPS).

Repeat photograph of Saguaro National Monument (now Saguaro National Park) East, Rincon Mountain District. This photo was taken in 2010 by Dr. Ray Turner, USGS and is a match of a 1935 photograph taken by the National Park Service (NPS).

Saguaro National Monument is now Saguaro National Park. The decline is saguaros has continued but at a rate slightly less steep than predicted. Very few of the saguaro present in 1935 remain. Meanwhile, the regeneration of this forest has already begun, as shown by findings from a long-term study-plot located at left midground.

A Tegeticula maculata Yucca moth is perched & depositing a pollen ball onto a stigma of a Yucca plant (Hesperoyucca whipplei). Photo by Sherwin Carlquist, 2010.

Beaches in the rough terrain of Grand Canyon are a valued resource by hikers and river runners because they are fairly flat and vegetation free. 

Boats at a large campsite area along the Colorado River in Grand Canyon, 2009. USGS photo, public domain.

Riparian vegetation along West Clear Creek in Arizona. Photo by Chris Calvo, National Park Service. 

Boat equipped with multibeam sonar surveying the bed of the Colorado River in May 2009. Instrument in foreground is robotic total station that automatically tracks boat location and radios the position to a computer on the boat 20 times per second.

Boat equipped with multibeam sonar surveying the bed of the Colorado River in May 2009. Instrument in foreground is robotic total station that automatically tracks boat location and radios the position to a computer on the boat 20 times per second. 

U.S. Geological Survey Research Ecologist Jeff Lovich holding a radioed desert tortoise at the Mesa wind farm near Palm Springs, California.

Repeat photography from about 1945 (top panel) and 2008 (bottom panel) showing channel narrowing over time in a portion of the Rio Grande in Big Bend National Park. 

The Needles District, Canyonlands National Park

Sandbars in Grand Canyon are influenced by the amount of sand avaiable to build sandbars and the flow of the river, both of which are affected by Glen Canyon Dam.

View of reattachment sandbar located near the Carbon Creek drainage on Colorado River (River Mile 65).  Photo is from the long-term sandbar monitoring remote camera time-series archives, and shows the sandbar two months after the 2008 Spring High Flow Event.

Dr. Jeff Lovich holding a native and non-native turtle in each hand near Montezuma Well, AZ, April 2008. The small turtle is a native Sonora mud turtle (Kinosternon sonoriense) and the larger turtle is a non-native Red-eared slider (Trachemys scripta elegans). The red-eared sliders have been removed from Montezuma Well.

Dr. Jeff Lovich kneels near spur-thighed tortoises at a rescue in Phoenix, AZ. Spur-thighed tortoises, also called Greek tortoises, are native to northern Africa through central Asia.

The flat-tailed horned lizard (Phrynosoma mcallii) lives in low, level, desert areas of Arizona, California, and Mexico that are suitable for solar energy development. Photo by Robert Lovich.

A Sonora Mud Turtle (Kinosternon sonoriense) hatchling, Montezuma Well, with a quarter for a size comparison. Kinosternon sonoriense are found only in aquatic habitats in the southwestern United States and northwestern Mexico. They are listed on the IUCN Red List and some subspecies are listed as critically imperiled. Photo by Charles Drost, USGS, SBSC.