| The 2015 SaKe survey will span the west coasts of the U.S. and Canada from approximately
lat 32.8°N (San Diego) to approximately lat 54.65°N (Dixon Entrance, Canada). Eastern
and western extents will primarily range from the 20-m isobath or as close to shore
as is safely navigable, to either the 1,500-m isobath or a point 35 nmi west of the
inshore waypoint, whichever is farther offshore. The primary goal of the survey is
to estimate the biomasses, distributions, and biological compositions of populations
of Pacific hake and CPS using data from an integrated acoustic and trawl survey off
the west coasts of the U.S. and Canada from approximately San Diego, California (lat
32°48.02?N) to the Dixon Entrance, Canada (lat 54°39.00?N). Besides Pacific sardine,
the other CPS of interest for the SWFSC are those comprised in the Pacific Fisheries
Management Council Fisheries Management Plan (PFMC, 2011) including: Northern anchovy
(Engraulis mordax), Pacific Mackerel (Scomber japonicus), Jack Mackerel (Trachurus
symmetricus). The NWFSC and SWFSC are interested in all species of euphausiids found
within the U.S.? West Coast EEZ. The current sampling resolution will probably not
allow for a comprehensive assessment of all anchovy sub-populations. In particular,
those residing in the Southern California Bight and off the Columbia River plume might
require additional effort given their patchy distribution. SaKe 2015 will continue
to monitor the populations of Ecosystem Component Species (ECS; PFMC, 2011), in particular
Pacific Herring (Clupea pallasii). Continuously sample multi-frequency acoustic backscatter
data using the ship?s Simrad EK60 scientific echosounder system. These data will be
used to estimate the distributions and abundances of hake and the CPS assemblage.
Conduct daytime trawling to classify observed backscatter layers to species and size
composition and to collect specimens of hake and other organisms. Conduct nighttime
(i.e., between sunset and sunrise) surface trawling to collect specimens of coastal
pelagic fishes (CPS) and other organisms. These data will be used to classify CPS
backscatter to species and their size distributions. Nighttime sampling operations
will conclude in time for the ship to resume running east-west acoustic transects
by sunrise. Image fish using a portable X-radiograph machine for the purpose of target
strength modeling and estimation. Collect a variety of other acoustic, biological,
and oceanographic samples relevant to hake and CPS distributions. These data are vital
for the surveys and assessments of hake and CPS. Continuously sample sea-surface temperature,
salinity, and chlorophyll-a using the ship?s thermosalinograph and fluorometer. These
data will be used to estimate the physical oceanographic habitats for each target
species. Continuously sample air temperature, barometric pressure, and wind speed
and direction using the ship?s integrated weather station. Continuously sample pelagic
fish eggs using the Continuous Underway Fish Egg Sampler (CUFES). The data will be
used to estimate the distributions and abundances of spawning hake, and multiple CPS.
Sample profiles of temperature and salinity using a combination of an underway conductivity-temperature-depth
(CTD) system during the day or a standard CTD system with water-sampling rosette and
other instruments at nighttime stations, as time allows. Sample plankton using a Vertical
Ring Net net at nighttime stations, as time allows. These data will be used to estimate
the distribution and abundance of ichthyoplankton and zooplankton species. Continuously
sample multi-frequency acoustic backscatter data using the ship?s Simrad ME70 multibeam
echosounder system, synchronized and configured to not interfere with the EK60s. Optically
verify CPS backscatter while underway conducting acoustic transects, using a cast
stereo camera system.Optically observe fish behavior inside nighttime trawls using
cameras and lights mounted inside the net. |