Upstream water withdrawals, not climate forcing, dominate desiccation of Lake Abert (USA)

Lake Abert (the western Great Basin, USA), designated a critical habitat under the Western Hemisphere Shorebird Reserve Network, is at near record historic low levels and ultra-high salinities that have resulted in ecosystem collapse. Recent paper by Johnnie N. Moore is focused on determination of the direct human effects and broader climate controls on Lake Abert. It illustrates the broader problem of saline lake desiccation and suggests future solutions for restoration of key habitat values. A 65-year time series of lake area was constructed from Landsat images and transformed to lake volume and salinity. It is demonstrated that under natural conditions the lake would have higher volume and lower salinities. Without withdrawals, the lake would have maintained annual mean salinities mostly within the optimal range of brine shrimp and alkali fly growth. Change in climate alone would not produce the recent low lake volumes and high salinities that have destroyed the brine shrimp and alkali fly populations and depleted shorebird use at Lake Abert. Large scale withdrawal of water for direct human use has drastically increased the imbalance between natural runoff and evaporation during periods of drought in saline lakes worldwide but could be offset by establishing an “environmental water budget” to lay a foundation for the conservation of saline lake habitats under continued threats from development and climate change.

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