Outer Hood Canal Early Marine Juvenile Salmonid Study and Marine Biodiversity Study (NaGISA) Technical Summary Report, 2010

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1 Outer Hood Canal Early Marine Juvenile Salmonid Study and Marine Biodiversity Study (NaGISA) Technical Summary Report, 2010 Introduction: This project was a two-year pilot study to develop and implement methods to better describe juvenile salmon and steelhead patterns of use and behavior in the nearshore areas of outer Hood Canal and Admiralty Inlet. The primary objectives of this study were 1. to document species abundance and distribution during outmigration; 2. to record and analyze size, condition, growth factor, diet and other constraining environmental mechanisms that affect the early marine life history of salmonids; 3. to investigate the linkages between juvenile growth and adult marine survival potential. Sampling in 2009 and 2010 included bimonthly beach seining, early peak, mid peak and late peak surface trawl collections, and zooplankton and water quality sampling. An expanded sampling regime was implemented at Tala Point that included population assessments using hydroacoustics, temperature monitoring, and multiple recurring surface trawls and beach seine sets within 24 hour segments during peak abundance. This objective of the intensive monitoring component was to describe diurnal patterns of salmonids and other biota within the nearshore. Additionally, a focus of the hydroacoustic work was to continue our development sampling of passive/non-intrusive methods. Also at our intensively monitored site, NaGISA intertidal and subtidal transects were developed and sampled for marine biodiversity and more detailed habitat characterization. A major outcome of this pilot project was the formation of a partnership with NOAA, through which we have created a collaborative and collective sampling effort that expands our current tow net sampling throughout the entire Puget Sound Basin. The data we have collected through this and the up-coming project will help support and calibrate existing stock assessment and forecasting tools as well as help prioritize and defend associated nearshore habitat restoration projects. Project Implementation: This project was a multi-faceted nearshore study and developmental pilot project comprised of the following primary sampling components: Surface trawl tow net Beach seine Zooplankton & water quality sampling Hydroacoustics Nearshore temperature survey Habitat characterizing & NaGISA biodiversity survey Summary of all activities Nearshore (5m depth) surface trawl sampling occurred monthly from June through October and May through September in 2009 and 2010 respectively. The entire catch was sampled and biomass was determined by species. Length frequency and bell diameter data was collected from up to 25 of each fish or jelly species encountered. Up to

2 25 juveniles per haul were processed for marked/unmarked/cwt, fork length, weight, volumetric displacement, and presence of sea lice. A sub-sample from each sampling location were sacrificially sampled for otolith extraction, CWTs, BKD, stomach contents, genetic material, stable isotopes, and insulin-like growth factor-i (IGF-I) and 41 kda IGFBP (IGF binding proteins). Beach seines were conducted from April through September in 2009 and 2010 on a bimonthly schedule. Seine sites were paired with the tow net locations, and the same, non-sacrificial data was collected on salmonids. All other species were counted. 24-hour beach seines events were carried out in 2009 and Water quality and zooplankton sampling was conducted at each surface trawl event. Water quality data was collected with a CTD and chlorophyll was sampled from a 1meter water sample, and 10 meter vertical zooplankton tows were collected. Additionally, bimonthly 100 meter vertical zooplankton tows were collected at a central location in north Hood Canal. We implemented an exploratory hydroacoustic sampling program using various deployment methods. In the first year of the project, we rented a Biosonics DTX array and Didson. We used these units in conjunction with the surface trawl, as a moving station towing along the shoreline, and as a stationary station aimed at the shore during the 24-hour beach seine event. In the second year, we purchased a high-end consumer-level sonar unit for further research and development of monitoring methods. We constructed a stationary design with an anchored buoy system that was deployed at a site along the shoreline at Tala Point. This was a relatively successful system that is potentially capable of capturing nearshore abundance data. Our experience demonstrated that if hydroacoutics are going to be used along with a moving vessel, they must be towed and aimed down. Collecting data about biota going into net was unsuccessful because of surface refraction. However, by towing the hydroacoustic instrument, it may be possible to obtain a reference to what is not being captured in the trawl. In protected areas, the stationary anchored buoy design should be able to minimize surface refraction, and may be a highly effective monitoring design. We will continue work with this system during the 2011 season. The nearshore temperature survey was a 24-hour temperature pilot project tracking shortterm temperature fluctuations. An array of temperature monitors was deployed at depth profiles along the shoreline at Tala Point. Diurnal temperature fluctuations were tracked. Paring temperature monitoring with the hydroacoustic model described above will create a passive sampling technique to describe daily and seasonal variation in distribution of fish and other biota. Better understanding how biota behave in the nearshore environments is critical to interpreting data collected using traditional snap shot techniques such as beach seining. The habitat characterizing program implemented through this project consisted of a biodiversity survey in conjunction with NaGISA, a CoML nearshore monitoring program. We partnered with Seattle Aquarium, Northwest Indian College, Point No Point

3 Treaty Council and a phycologist from University Vancouver, to complete a set of intertidal and subtidal survey transects at Tala Point in June Data will be available internationally through a centralized database. This initial set of surveys will serve as a baseline biodiversity assessment for on-going monitoring. In addition to the intensive NaGISA surveys, we developed a habitat survey program using ROV to characterize habitat based on substrate, algae type and density that will be used at all of tow net and beach seine locations. Results: Many components of this project are still being worked on with much data still needing to be analyzed and reported on. The following sections (Figures 1 through 12 and Table 1) summarize preliminary results surface trawl tow net data. Although we developed and implemented a number of significant sampling programs, because of the short timeframe, and the experimental nature of many of the other project components, currently the most pertinent information can be derived from the tow net data set. Please refer to Figures 1 through 12 and Table 1 below. Discussion: Salmon abundance & distribution: In 2009, sampling began in June. Because we observed peak abundances of all of species in the first sampling date, we began our sampling effort a month earlier in In 2009, Chinook were present in relatively high numbers throughout the sampling season, whereas chum and coho abundances dropped off significantly from initial peaks by July. In 2010, the abundance patterns were different. Overall coho and Chinook abundance was greater in 2009 than In 2010, peak abundance of coho was observed over a two month period, as compared to a single peak in These patterns suggest that we may have missed a significant portion of the outmigration population in May Chum abundance was greater in 2010 than We observed over 3500 fish in June and 570 in July 2010, as compared to just over 700 in June Again, this suggests that we may have missed a large portion of the outmigration chum population by beginning sampling in June. Compared to the other salmonid species, Chinook showed the greatest spatial and temporal distribution within our northern Hood Canal study site. This indicates that the northern Hood Canal habitats may be more important to the early marine survival of Chinook than other salmonid species. Based on our abundance data, Tala Point is an important location for outmigrating juvenile salmonids, regardless of habitat type and quality. Tala Point appears to be receiving multiple populations from the entire Puget Sound. Our genetic and CWT data should confirm this assumption. Secondly, although Bush Point is also geographically available to multiple out-migrating populations, our site abundance data indicates that the salmonids are preferencing a migratory path along the southern shore of Admiralty Inlet.

4 Condition factor: Juvenile salmonids appeared to have out-migrated earlier in 2009 than in In 2009, the fish grew faster in length and their condition factor increased at a greater rate throughout their residence in north Hood Canal, allowing the fish to achieve greater prey capture and predator avoidance. These differences between the two years suggest that the 2009 population should have an increased survival rate over the 2010 population. Diet: Both marine and terrestrial prey items were present in all species, indicating that from a prey availability standpoint both the marine and terrestrial environments are import. However, the ratio of composition was very different between the species, suggesting that some species may be more directly reliant of specific habitat types or shoreline conditions than others. We do not have sufficient data to correlate gut contents to specific sample sites; 2010 samples have not been processed yet. During sampling, gut contents were classified to the lowest taxanomic level possible and quantified numerically. Our next samples will include a gut full-ness measurement, as well as mass quantification by prey type. This additional data will provide more insight into the relative importance of different prey items. Conclusion: We will be continuing and scaling up our nearshore juvenile salmon, ecosystem and NaGisa efforts in the years ahead. Our first two years of townetting and beach seining have provided large amounts if important data we will be analyzing in the months ahead. This effort has provided a great spring board for collaborative partnerships as we started of putting the effort into connections with other Puget Sound researchers, primarily the Skagit River System Cooperative and NOAA. We worked with them in their larger scale EPA/Puget Sound proposal and now have a much larger role working with them for a Puget Sound Wide effort. This research is beginning in April and we are looking forward to the 2011 season for much more expanded levels of information and continuing to adaptively manage our focus and goals to fit appropriately defined priorities. The detailed and expanded condition factor analysis has been extremely successful and we are gearing up for expanded IGF sampling and complex physical condition factor sampling including length, weight, girth and volume in order to develop a modified condition factor that can be used as a tool from marine survival estimation as well as nearshore and early marine ecosystem challenges constraining or supporting growth and survivals. We will fold into this next years efforts additional scales of focus including; data from intensively monitored Mid Hood Canal River systems, particularly the Dosewallips River; NaGisa sampling with efforts to get other Tribe s and groups to add additional Puget Sound sites; developing a near lab quality on board scale system using a custom gimble table with a gyro stabilization system; more genetic evaluations and more detailed and complex expansions of condition factor analysis.

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