Nearshore larval fishes of Puget Sound

Abstract

Puget Sound is home to about 220 fish species that produce pelagic larvae, however little is known about their early life history. Larval fishes were collected from the six basins (Rosario, Whidbey, Admiralty, Central, Hood Canal, South) that comprise Puget Sound’s nearshore habitat from April 2011 to February 2012 to explore distribution and abundance patterns within the region. This study marks the most extensive collection of larval fishes to date within Puget Sound both spatially and temporally. A total of 9,317 specimens from 28 families and 71 species were collected. Abundance peaked in spring, particularly April, was lower during summer months, was close to zero during winter, and rose again in early spring. Species counts followed similar seasonal trends. Estimated species richness was above 40 species for most basins, but was significantly lower in Hood Canal and Admiralty. The most specimens collected were from the following species: Pacific Herring (Clupea pallasii), Pacific Sand Lance (Ammodytes personatus), Arrow Goby (Clevelandia ios), and Starry Flounder (Platichthys stellatus). In-depthanalysis of seasonal and spatial patterns was performed for Pacific Herring, Pacific Sand Lance, and Starry Flounder. These three species have different spawning patterns and larval durations which influence their experience during the larval phase. All three species peaked in abundance during spring, but Pacific Herring was present during summer months, while the other two were absent. Herring was the only species present in more than a few instances in Hood Canal Basin. Herring and Starry Flounder were present in high density in South Basin, while Pacific Sand Lance and Pacific Herring were present in high density in the northern basins of Whidbey and Rosario. This study is the first time many of these seasonal and spatial trends have been described for larvae of these species within Puget Sound. It is clear from this dataset that nearshore habitat is home to a diverse range of larval fish species within Puget Sound. More sampling of the total larval fish community in the region over several years is needed to identify interannual variability and to confirm the results of this study. The general lack of regional larval fish distribution and abundance data impedes further action to protect these hundreds of species who produce pelagic larvae and also means we have insufficient data to plan for future needs of these species, including future vulnerabilities created by changes in climate and habitat.