LOUIE , K.D.; KOEPFLI, K.P.; JACOBS, D.K.: Genetic Variation in the Eastern Pacific Bay Pipefish (Syngnathus leptorhynchus)

The bay pipefish (Syngnathus leptorhynchus), inhabits estuaries along the eastern Pacific from Alaska to Baja California. This pipefish is elongate, slender, and cryptic in its protective eelgrass habitat. Fishes of this species are specialized because females deposit their eggs directly into the brood pouch of a male, where they are fertilized, nourished, and protected until they hatch as free-swimming juveniles. Extensive morphometric and meristic variation has been found across the range of this species, causing both difficulty in identification and distinction from other pipefish species. Due to this morphological variation, specialized reproductive strategy, and affinity to eelgrass habitat, it is hypothesized that S. leptorhynchus may also exhibit both marked genetic variation and geographic structure. Using mitochondrial control region sequence data, this study examines the intraspecific variation and genetic structure of individuals of S. leptorhynchus from locations from southeast Alaska to southern California. Preliminary data suggest both genetic variation and geographic structure within the species.