Maternal Input of Striped Bass: Determining a Mother's Life History From the Progeny

Striped bass (Morone saxatilis) have two life history strategies: anadromy and residency.  Anadromy is when a species lives in saltwater as an adult and spawns in freshwater, while residents stay in freshwater throughout life.  It is possible to determine whether or not an individual is anadromous or resident by examining trace elements in the otoliths (ear bones), specifically Strontium, which is directly related to water salinity.  We take this knowledge a step farther to determine that, by looking at larval otolith strontium levels, the life history of the mother can be determined.  This research discovers how related the progeny and maternal otoliths are and whether there is a concentration of elements in the mother’s tissue that would help explain how possible elemental signatures are passed on.   The life history strategy (resident or anadromous) of the mother can be seen in the core of these progeny’s otoliths and the primordium of adult fish based upon the Strontium levels.  Since the progeny’s otolith signatures can be traced back to the mother’s life history strategy, we can then determine the relative production and survival of progeny from anadromy versus residency.