Increasing Nitrogen levels in Rocky Mountain National Park

threaten Greenbacks and Other Trout in Rocky Mountain National Park

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Ongoing studies by National Park Service and U.S. Geological Survey scientists reveal that air and water quality in Rocky Mountain National Park are declining. Specifically, increased levels of nitrogen deposition in the park are saturating the Park's soils, and changing the pH balance in lakes and coldwater streams. Annual nitrogen deposition levels in the park are now 15 times greater than pre-industrial, natural levels. These pronounced increases, which have already begun to change algae species composition in Park streams, are disproportionately affecting the eastern side of the Park. The major sources of nitrogen pollution (usually in the form of NOx or NH4) are industrial emissions, motorized vehicle exhaust, and agriculture.

Rocky Mountain National Park is a fragile ecosystem in the sense that it has a naturally low acid-buffering capacity. This means that as further nitrogen deposition occurs and waters begin to acidify, certain pH sensitive species such as trout may become the first victims of nitrogen loading. One recent Park publication stated, "Eventually these resources become acidic and cease to support sensitive species such as fish." The Park is the largest protected management area of the federally threatened Greenback Cutthroat Trout, Colorado's state fish and a species formerly on the brink of extinction. Dedicated Colorado Trout Unlimited members have already put some 7,000 volunteer hours into Greenback Cutthroat habitat restoration and conservation.

Park and USGS scientists have reported increased nitrogen loading that jeopardizes the Park's soils, lakes, and streams.

Scientists believe that these increases, if not slowed andeventually remedied, could have serious adverse impacts on bothecosystem and human health.

Ecological consequences of nitrogen loading are already evident, as species within different communities are changing.

Federally threatened species such as the Greenback Cutthroat Trout could be put at further risk because of their sensitivity to these environmental factors.