Comparing Otolith Trace Element Partition Coefficients Among Carp Species

If Asian carps are discovered in Lake Erie the need to identify natal origins will be very important. Invasive species biology strongly suggests the importance of rapid action when an invading population is very small. The primary objective of this study was to preemptively establish a multi-variance algorithm using both asterisci (vaterite) and lapilli (aragonite) otolith chemistries for discriminating natal origins and recreating life histories of Asian carps that may eventually utilize the Sandusky, Maumee, and Grand Rivers for spawning and nursery habitat. To accomplish this objective we, 1) determined the trace element (Sr, Ba, Mg) otolith to water partition coefficients for Common Carp over a board range of water chemistries including those characteristic of the Sandusky, Maumee and Grand Rivers and 2) determined the elemental partition coefficients for Asian carps (Grass Carp, Bighead Carp, and Silver Carp) from the same water mass for both asterisci and lapilli otoliths. Comparisons were then made between species. Once these chemical tags are firmly established, we can rapidly identify nursery habitats for any Asian carps found in Lake Erie waters, thus allowing managers to focus rapid eradication efforts in these areas.