The San Marcos salamander, Eurycea nana, is a light reddish-brown translucent salamander about 2-5 cm in length. E. nana is found only in
Spring Lake and a portion of the San Marcos River.
Which human activity would most likely decrease the ability of the
salamanders to survive?

The addition of a new food source into the river that limits competition for
resources

Tourism that helps fund the educational programs related to river ecosystem
conservation

Public transportation that reduces the number of automobiles that contribute to
pollution runoff into the river

Increasing water consumption that decreases the flow of clean water from the
springs that feed the river