Using the Tools of Conservation Paleobiology to Assess the Impact of the Engineered Spring-Flood of the Colorado River

Paleontological Research Institute, Ithaca NY

Investigators

Abstract

Using the Tools of Conservation Paleobiology to Assess the Impact of the Engineered Spring-Flood of the Colorado River By Gregory P. Dietl, Paleontological Research Institute, EAR-1420978 ABSTRACT The over allocation of the Colorado River's water has led to the ecological devastation of its delta and lowermost channel. The Colorado River annually delivered over fifteen million acre-feet (~1.85x1010 m3) of water to its delta but in recent years that number has been zero. In 2012, via a bi-national agreement known as Minute 319, environmental pulse flows equal to approximately 1% of the natural annual river discharge were negotiated by the United States and Mexico to be released over a five-year trial period. While this engineered environmental flow has the potential to be a restoration success story, there is a crucial gap in our knowledge: no studies on the ecology of the molluscan community in the lowermost channel of the river are available to provide a benchmark for evaluating the success of this restoration effort. The first pulse will be released in the early spring of 2014, providing a small window in which to establish a baseline for current conditions. This proposal thus seeks support to use a relatively simple community-based approach - comparison of molluscan living and time-averaged death assemblages - developed by conservation paleobiologists to establish a baseline. The samples collected will provide a unique perspective on the composition of the pre-pulse-flow community that is not available from any other source, which will allow the asking of future questions about the success of the pulse flows.