Patterns of Surf Smelt, Hypomesus pretiosus, Intertidal Spawning Habitat Use in Puget Sound, Washington State

Surf smelt Hypomesus pretiosus are an important part of the Salish Sea food web and obligate beach spawners, yet little is known about the spatiotemporal distribution of spawning and beach characteristics related to spawning success. We counted smelt eggs at 51 sites around Camano Island, Puget Sound, Washington every 2 weeks for 1 year and at 13 of those 51 sites each month in the following year. At each site, we measured beach characteristics hypothesized to affect spawning habitat suitability as measured by egg abundance and mortality. Eggs were collected at 45 sites and pooled by month for analyses. Few sites (N=10, 19.6 %) contributed 87 % of total eggs and 89 % of all live eggs collected. Mean total egg counts at sites were higher (p< 0.019) in Julâ€"Sep (1,790.7, SE=829.5) than in Janâ€"Mar (26.1, SE=10.2). Principal component and regression analyses suggested that aspect, fetch, solar radiation, and beach temperature predicted egg abundance but not mortality. Because a small proportion of sites appear to support most spawning activity, a conclusion consistent with year 2 egg counts, impacts to relatively few beaches could greatly affect surf smelt production.