Seagull Lake, Western Eyre Peninsula, South Australia: A Saline Lake to Benefit from Climate Change?

As a result of climate change, salt lakes on Eyre Peninsula are predicted to have shorter hydroperiods. Already there are salinity increases due to land use changes, so major decreases in biodiversity are expected. The likely situation is different however for the few lakes receiving waters via marine springs, with Seagull Lake, 20 km south of Streaky Bay, the best example. It has been thoroughly surveyed as a base to assess future changes. This lake originated about 6000 years ago as a marine bay, since occluded by coastal dunes. Its waters are a balance between meteoric sources, groundwater and marine water via springs with seasonal fluctuations due to input variations and evaporation. A conceptual model closely matched field observations. Presently the main lake varied in salinity seasonally from 75 to 200 g/L, with the spring virtually constant at 37–40 g/L. Plants in the lake and its palustrine margins numbered 25 species arranged into 18 floristic associations. Of particular interest are the...