• Three biological regions converge on the Dolan Falls Preserve: the Edwards Plateau, Chihuahuan Desert and Rio Grande Plain brushland. As a result, many distinct ecosystems overlap to create rich biodiversity. Three biological regions converge on the Dolan Falls Preserve: the Edwards Plateau, Chihuahuan Desert and Rio Grande Plain brushland. As a result, many distinct ecosystems overlap to create rich biodiversity.

    Three biological regions converge on the Dolan Falls Preserve: the Edwards Plateau, Chihuahuan Desert and Rio Grande Plain brushland. As a result, many distinct ecosystems overlap to create rich biodiversity. Leslie Boorhem-Stephenson

  • Formations in the rock show thousands of years' worth of erosion on the Dolan Falls Preserve. Formations in the rock show thousands of years' worth of erosion on the Dolan Falls Preserve.

    Formations in the rock show thousands of years' worth of erosion on the Dolan Falls Preserve. Leslie Boorhem-Stephenson

  • During heavy rains, floodwaters surge through this grotto at the Dolan Falls Preserve. During heavy rains, floodwaters surge through this grotto at the Dolan Falls Preserve.

    During heavy rains, floodwaters surge through this grotto at the Dolan Falls Preserve. Leslie Boorhem-Stephenson

  • A look at tree trunks and brush that washed down from the cliffs during a flood on the Dolan Falls Preserve. A look at tree trunks and brush that washed down from the cliffs during a flood on the Dolan Falls Preserve.

    A look at tree trunks and brush that washed down from the cliffs during a flood on the Dolan Falls Preserve. Leslie Boorhem-Stephenson

  • A butterfly on the Dolan Falls Preserve. A butterfly on the Dolan Falls Preserve.

    A butterfly on the Dolan Falls Preserve. Leslie Boorhem-Stephenson

  • A partially decomposed deer skull on the Dolan Falls Preserve. A partially decomposed deer skull on the Dolan Falls Preserve.

    A partially decomposed deer skull on the Dolan Falls Preserve. Leslie Boorhem-Stephenson

  • Douglas Meyer, the Devils River project manager for the Nature Conservancy's Dolan Falls Preserve, stands in a large cave at the preserve. Many caves on the preserve served as shelter for indigenous tribes that used to inhabit this area. Douglas Meyer, the Devils River project manager for the Nature Conservancy's Dolan Falls Preserve, stands in a large cave at the preserve. Many caves on the preserve served as shelter for indigenous tribes that used to inhabit this area.

    Douglas Meyer, the Devils River project manager for the Nature Conservancy's Dolan Falls Preserve, stands in a large cave at the preserve. Many caves on the preserve served as shelter for indigenous tribes that used to inhabit this area. Leslie Boorhem-Stephenson

  • Meyer shows a fibrous plant species found on the preserve that can be used for twine or rope. Meyer shows a fibrous plant species found on the preserve that can be used for twine or rope.

    Meyer shows a fibrous plant species found on the preserve that can be used for twine or rope. Leslie Boorhem-Stephenson

  • A kayak and canoe entry point on the Devils River, an hour west of Del Rio. There are few public entry points available, as much of the land that the river runs through is private property. A kayak and canoe entry point on the Devils River, an hour west of Del Rio. There are few public entry points available, as much of the land that the river runs through is private property.

    A kayak and canoe entry point on the Devils River, an hour west of Del Rio. There are few public entry points available, as much of the land that the river runs through is private property. Leslie Boorhem-Stephenson

  • Meyer points out pictographs made by American Indians who used to inhabit the area. Meyer points out pictographs made by American Indians who used to inhabit the area.

    Meyer points out pictographs made by American Indians who used to inhabit the area. Leslie Boorhem-Stephenson

  • Dolan Falls is directly downstream from the confluence of the Devils River and Dolan Creek. Dolan Falls is directly downstream from the confluence of the Devils River and Dolan Creek.

    Dolan Falls is directly downstream from the confluence of the Devils River and Dolan Creek. Leslie Boorhem-Stephenson

  • Facing downstream from Dolan Falls on the Devils River. The river is fed by freshwater springs that flow from the limestone cliffs above.

*Editor's Note: An earlier version of this slideshow incorrectly identified a butterfly as a monarch butterfly.
Facing downstream from Dolan Falls on the Devils River. The river is fed by freshwater springs that flow from the limestone cliffs above.

*Editor's Note: An earlier version of this slideshow incorrectly identified a butterfly as a monarch butterfly.

    Facing downstream from Dolan Falls on the Devils River. The river is fed by freshwater springs that flow from the limestone cliffs above. *Editor's Note: An earlier version of this slideshow incorrectly identified a butterfly as a monarch butterfly. Leslie Boorhem-Stephenson

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