Factors Affecting the Distribution and Abundance of the Orangethroat Pikeblenny, Chaenopsis alepidota.

Abstract

Little experimental work has been done on fish/invertebrate host interactions in temperate water systems. So during the summer of 1999, we began the preliminary work necessary to examine the nature and effects of the association between a fish, the orangethroat pikeblenny (Chaenopsis alepidota) that strictly occupies the tubes constructed by a polychaete worm (Chaetopterus variopedatus). Our initial goals were to locate persistent populations of pikeblennies and determine whether recruitment at these or unoccupied sites could be promoted by introducing artificial worm tubes. Although pikeblennies were found within worm tubes a three of the 15 sites surveyed on the lee side of Santa Catalina Island, they were seen only in gravel (not sand) habitats and in low numbers (1 to 3/site) despite reports to the contrary in the literature. Consequently, we focused our efforts on deploying two arrays of artificial tubes (10 small and 10 large tubes/array) at each of five sites where either fish were present (n=1), had been previously reported (n=2), or never reported (n=2). Currently each array is being monitored on a monthly basis for recruitment by fish.