Summary of Coastal Intertidal Forage Fish Spawning Surveys: October 2012 – October 2014
 
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Summary of Coastal Intertidal Forage Fish Spawning Surveys: October 2012 – October 2014

Category: Fish/Shellfish Research and Management - Management and Conservation

Date Published: January 2015

Number of Pages: 65

Publication Number: FPA 15-01

Author(s): Mariko Langness, Phillip Dionne, Daniel Masello, and Dayv Lowry

ABSTRACT:

Marine spatial planning (MSP) involves the identification and mapping of marine resources and human interactions with these resources, the weighing of costs and benefits to diverse stakeholders, and the development of long-term utilization plans. As part of a coast-wide MSP process funded by the Washington State Legislature, the Washington Department of Fish and Wildlife (WDFW), in collaboration with the Hoh, Makah, Quileute Indian Tribes, and Quinault Indian Nation, conducted a 24-month survey in an effort to document the presence of eggs deposited by forage fishes spawning in the intertidal. From October 2012 through October 2014, beaches along the Washington outer coast were surveyed for Surf Smelt Hypomesus pretiosus, Night Smelt Spirinchus starksi, and Pacific Sand Lance Ammodytes hexapterus spawn. The specific goals of the study were to: 1) subsample the breadth of intertidal reaches along Washington’s outer coast monthly; 2) identify forage fish eggs found to the lowest taxonomic level possible; and 3) geo-reference all survey data to provide an easily accessible overview of sampling effort and egg detections to date. The results for year-one of this study are reported elsewhere (Langness et al. 2014) and the results for year-two are presented in detail here. Yeartwo results were integrated with year-one survey data to provide a comprehensive, two-year evaluation. Over the two-year survey period, we sampled 89% of possible spawning habitat on the outer coast, and documented 40 spawning sites. Over the 13-month survey from October 2013 to October 2014, 761 sites were allocated, and 654 (86%) were sampled. Smelt eggs were present at 32 of these sites, while eggs of any species were not detected at the remaining 622 sites. Of the sites where smelt spawn was present, samples collected from 20 of the sites met the WDFW standard of containing a minimum of 2 eggs. Ten of these 20 sites are newly documented spawning sites. Spawn was documented in each month from January through October, one month earlier and one month later than suggested by our prior survey year (Langness et al. 2014). The number of documented spawning sites peaked in May and the number of eggs peaked in September. The geographical range of spawning sites remained clustered within the Quinault and Kalaloch-Hoh-Quileute beach zones; ranging as far south as site 365 (south of the Quinault River) and as far north as site 555 (south of Goodman Creek). The recurring presence of eggs at different sites and the presence of multiple egg stages at a single site indicate that several spawning events occurred during the season. We expect that further sampling would identify a broader spatial and temporal range of smelt spawning along the outer coast. Sampling over multiple seasons would likely increase egg detections as some sites may have only limited use on a seasonal or annual basis. Continued sampling could also provide the opportunity to improve methods that would enable a higher detection probability and greater efficiency in sampling. As our comprehensive study allowed us to determine the areas of spawning on the outer coast, focused sampling on spawning beaches in the Quinault and Kalaloch-Hoh-Quil beach zones is suggested for any future research efforts.