Age and Growth of the Divine Dwarf Goby Eviota epiphanes from O‘ahu, Hawai‘i

Abstract

I examined the age and growth of the divine dwarf goby Eviota epiphanes, a small, cryptic reef fish, in order to determine its role in the nearshore marine ecosystems of Hawaiʽi. Age was determined by counting presumed daily increments of transversely sectioned sagittae otoliths from 53 specimens captured on Oʽahu, Hawaiʽi between August and November 2012. Post-settlement growth was best represented by the von Bertalanffy growth function with a correlation coefficient of 0.53 and a residual sum of squares of 150.3. From examination of otoliths and counts of presumed daily increments, the mean pelagic larval duration (PLD) was found to be 26.5 +/- 0.22 days (SE) and the estimated maximum age was approximately 60.5 days. The proportion of total lifespan represented by the PLD was 43.8%, which corresponds to 34 days of post-settlement life. Estimated daily natural mortality was 3.6%. The age at sexual maturity calculated from the von Bertalanffy growth function was 40.9 days (or 14.4 days post-settlement). Mean generational turnover was 50.7 days. The rapid growth and short life span of E. epiphanes supports the hypothesis that small reef fishes are an important food source for piscivorous species and therefore plays an important role in the energetics and productivity of coral reef ecosystems.