CRUISE PLAN R/V WECOMA
Oregon State University College of Oceanic and Atmospheric Sciences
Southeast Bering Sea Carrying Capacity - juvenile pollock habitat and
Ric Brodeur and Jeff Napp (NOAA/Alaska Fisheries Science
Center, (206) 526-4318, (206) 526-4148, Fax: (206) 526-6723), and
Phyllis Stabeno and Jim Schumacher (NOAA/Pacific Marine
Environmental Lab., (206) 526 6453, (206) 526-6197, Fax: (206) 526-6485).
June 30 - July 14, 1997
Scientist in charge: Matt Wilson, NOAA/AFSC (contact for questions)
(206) 526-6522, email@example.com
Sigrid Salo (PMEL), Jeremy Higgins (PMEL), Lorenzo Ciannelli (Univ. Wash.),
Lisa Britt (AFSC), Steve Porter (AFSC), Jay Clark (AFSC), Chris Baier (Univ.
Wash.), Gregg Savage (UCal Irvine), TBA (Ucal Irvine), Sarah Pautzke (WWU).
The southeast Bering Sea supports an abundance of species that are important
economically and culturally. Ecosystem-level management of this region
is desirable but requires some knowledge of the governing ecological mechanisms.
Based on abundance and commercial value, walleye pollock are an important
part of this ecosystem. Variations in pollock survival would thus likely
have a large impact on the regions' biotic and economic characteristics.
This cruise addresses two goals of the Southeast Bering Sea Carrying Capacity
(SEBSCC) Program. The first is to understand juvenile pollock-habitat interactions.
These interactions will be studied by conducting site-intensive sampling
along transects which cross a tide/wind-induced frontal region surrounding
the Pribilof Islands. Fluctuating environmental conditions are expected
to be an important source of variation in pollock survival. Thus, the second
SEBSCC goal addressed by this cruise is to occupy hydrographic stations
in an effort to develop biophysical indices useful for monitoring key physical
and low-trophic level aspects of the southeast Bering Sea region.
On June 30, approx. 10:00 ADT, the ship will depart Dutch Harbor and
steam to the southern end of the Biophysical Transect (53° 21.5'N;
168° 42.0'N). Hydrographic stations are then taken in order along the
transect according to the attached Biophysical Station Table and Map (Table
1, Figure 1). The order in which the Biophysical Canyon Transect and the
Juvenile Habitat Transects are occupied depends upon timing and travel
efficiency (Tables 1&2, Figures 1&2). The cruise will end when
the ship arrives back in Dutch Harbor at 9:00 am (ADT) on July 14.
A) Biophysical Monitoring.
1. A total of 38 stations will be occupied for this cruise objective.
Table 1 lists the station locations and station-specific operations, in
order of occupation (Figure 1). In brief, a CTD will be accomplished at
each station. At selected stations, (see Table 1) samples for chlorophyll
and nutrients will be taken using Niskin bottles on the CTD rosette. We
will then tow 20 and 60 cm bongo frames (150 and 333 µm mesh, respectively)
on the same wire for collection of zooplankton. Water sampling at Moorings
2 and 3 may require several CTD casts to obtain the requested chlorophyll
replicate samples. When doing deep CTD casts, make certain that any ancillary
instruments on the CTD (e.g. fluorometer) are rated for the depth of the
cast (1500 m at the deepest stations).
2. Canyon Transport Table 1 lists the stations locations and station-specific
operations (Figure 1). Order of occupation will be determined by the Chief
Scientist. In brief, a CTD will be accomplished at each station with one
water bottle sample at 5 m for nutrients. The fluorometer should be on
the CTD, but no chlorophyll samples will be taken. The CTD cast is followed
by a tow of the 20 and 60 cm bongo frames (150 and 333 µm mesh, respectively)
on the same wire for collection of zooplankton.
B) Sampling to satisfy the juvenile pollock habitat objectives is as
1. There are four Juvenile Habitat Transects detailed in the Table of
Juvenile Habitat Stations but the order in which they are sampled will
depend on timing and travel efficiency. Sampling each transect will take
approximately 20 hours and consists of three passes. The first pass along
each transect will be to conduct a CTD cast and a bongo tow (with 20 and
60 cm nets) at each of 7-10 stations (Table 2, Figure 2) (approx. 12 hrs).
Two more passes will be necessary: one to collect acoustic data along the
transect (approx. 3 hrs) and the other to collect micronekton at each of
three locations (approx. 5 hrs). These three locations will be determined
either by the degree of thermal stratification or simply the locations
sampled during September 1996 (Table 2), and sampling will be accomplished
using the Methot trawl. Both of the latter two passes on each transect
should be done at night. Allowing for 1 hour of twilight before and after
sunrise and sunset, there will only be about 5 hours of nighttime (ADT:
sunrise, ~06:40; sunset ~00:10) so it may be logistically difficult to
meet this diel constraint. Second choice, is to run the acoustic pass during
the day and collect micronekton at night (to reduce gear avoidance effects).
If acoustic passes are made during the day, every opportunity should be
made to identify the echosign. Removing diel differences will facilitate
comparisons among stations and transects but will add to the estimated
time necessary to complete the sampling of each transect (20 hrs). Accounting
for the diel sampling constraint and travel time between transects we estimate
that it will take about 7 days to complete the sampling of all four transects.
2. If time permits, some transects or stations may be repeatedly sampled
at different diel periods or with different gears. We will also attempt
to use the IKMT/MPS net to resolve vertical or meso scale horizontal patterns
in fish distribution.
3. The bird biologists (Ucal Irvine) will make observations of seabird
counts along and across the outer shelf of the southeastern Bering Sea,
and in the vicinity of the Pribilof Islands. Conditions permitting, they
will also attempt to collect birds as opportunity permits using a 12-gauge
shotgun and deployed in the Zodiac Mark II.
C) Methods for fishing each gear is described briefly. More details
regarding the typical deployment/retrieval routine for these gears is attached
(the routine for deploying and retrieving the IKMT/MPS will be established
on an earlier cruise (WE97-06A, 4-9 June 1997)).
1. The CTD and bongo nets will be fished to within 5 m of bottom except
as specified in Table 1. On the CTD care must be taken to not exceed the
maximum depth ratings of the attached instruments. We hope to monitor the
bongo depth using a SeaCat terminated to the end of the 0.322" (5/16)
wire on the trawl winch and connected to a deckbox and Personal Computer
in the dry lab. This will require slip rings. It is expected that three
scientists, 1 winch operator, and one crewman (or marine technician) will
be necessary when fishing the CTD and bongo nets. The 20 cm bongo net will
be attached to the wire above the 60 cm bongo and the array will be fished
off the starboard quarter using the trawl winch, boom, and boom crutch
and maintaining a wire angle of 45 degrees (only the sample from Net 1
of each bongo net will be preserved). Deploying and retrieving the bongo
nets may each require two scientists, one crewman, and a winch operator.
2. Both the Methot net and the IKMT/MPS net will be fished off the stern.
The Methot net will be fished over an oblique path down to 10 m off-bottom
using the stern A-frame and the coring winch. The IKMT/MPS net will be
fished variously depending on echosign. Realtime depths of the Methot and
the IKMT/MPS will be accomplished using Scanmar equipment (a small depth
sensor is attached to the net and a hydrophone draped over the side at
a depth of about 3 meters). We will also monitor the temperature at depth
using a mini bathythermograph (MBT) which is a self-contained unit that
attaches directly to the gear and records for a predetermined time. Deploying
and retrieving the Methot and the IKMT/MPS may each require two scientists,
two crewmen, and a winch operator.
Most of the needed equipment will be loaded using the ship's crane in
Seattle (12 May, Monday) but ScanMar equipment (about 100 lbs total) will
be loaded in Dutch Harbor (29 June, Sunday). All gear will be off-loaded
in Dutch Harber on 14 July (Sunday) beginning shortly after the ship docks
at 9:00 am (ADT). It is expected that off-loading will take approximately
2 hours (Hugh Milburn expects loading for the next cruise to take about
4 hours - this means that the scheduled "touch-and-go" will actually
include at least 6 hours at a dock). Storage in Dutch Harbor will be available
with advance notice at the FTS facility (FTS, Dutch Harbor / Vessel Support
and Supply Center / P.O. Box 1085 / Dutch Harbor, AK 99692 / Tel. 907 581-2490
/ Fax. 907-581-2491).
None will be used.
20 liters Formalin (37% formaldehyde)
12 liters Sodium borate solution
300 mls 95% Ethyl Alcohol (EtOH) (Jerry Hoff)
0.05 g MS-222
~10 liters 95% Ethyl Alcohol (EtOH) (Ucal Irvine)
12 gauge shotgun (Ucal Irvine)
OSU Marine Technicians: 1 requested
Electronics Technician: 1 requested
Coring winch and stern A-frame for fishing Methot; Trawl winch (5/16"
3-conducter cable) and boom crutch for fishing bongo nets over starboard
quarter and IKMT/MPS off the stern; Electromechanical swivels; Winch slip
Shipboard CTD system (with spare sensors); associated data display,
logging, and output systems; Sixteen 5 liter Niskin bottles (includes 4
spares); SeaTech Fluorometer.
Underway fluorometer and thermosalinograph, every 60s log: GMT date,
time, lat., long., temp., salinity, fluoresence, bottom depth.
GPS navigation system and INMARSAT phone/fax system for occasional scientific
use. The Ashtech system must be functioning for use with GPS navigation.
Sea-Bird 911+ CTD with
16-18 5-liter Nisken bottles, mounting pins and spares
CTD PAR with cables and mount
CTD fluorometer with cables and mount
CTD transmissometer with cables and mount
Sea-Bird deck unit
tape recorder or VCR
Ship speed, heading, high resolution position, wind speed, wind direction,
TSG conductivity, and TSG temperature should be recorded on a computer
every 60 seconds. This data should be backed up daily.
Wet and dry bulbs, air temperature and relative humidity should be manually
recorded by the bridge every four hours. The weather record will begin
at athe time of the first station and will end at the last sstation, or
as specified by the Chief Scientist. If the bridge watch is unable to record
the weather, please notify the scientist on watch.
A copy of the latest calibration sheets/documentation for all WECOMA
instrumentation used should be provided.
Fill out a Marine Operations Abstract (MOA) form, provided by FOCI.
This includes: GMT date, GMT time, position, depth, and operation. One
line of the MOA should be completed by bridge personnel for each operation
at each FOCI station. The standard time for recording data - both on computer
and on forms - will be GMT.
Sample processing space (sink w/ hood for formalin, seawater hose for
rinsing nets on deck and for rinsing codends/sieves in lab).
Location in the main dry lab to set up readouts for: wireout, GPS, bottom
depth, ship's speed, and deck units for SCANMAR (depth of Methot and IKMT/MPS),
Sea-Cat (depth of bongo and Tucker), and MPS.
Miscellaneous: Two portable chest freezers (each 15 cu. ft.) for nutrient
and chlorophyll samples; the storage van that fits on main deck under trawl
winch; plain paper copier.
USER SUPPLIED EQUIPMENT:
see attached gear list
OTHER BULKY, HEAVY ITEMS:
The multiple plankton sampler (MPS), which attaches to the aft end of
the Isaacs-Kidd midwater trawl (IKMT), is packed in a plywood box (approx.
3'x6'x6') (~400 lbs total) and may be stowed on the deck if somewhat protected
from spray and rain.
All of the following may be stored on the open deck:
1) Methot frames, depressors, and bridles (~800 lbs total),
2) IKMT spreader bar, depressor, and bridle (~200 lbs total),
3) Tucker "frame", and bridles (~200 lbs total)
4) 60 cm bongo frame and weight (100 lbs total)
5) 20 cm bongo frame
Name: Robert Sommer
Address: NOAA, AFSC, 7600 Sand Point Way N.E., Seattle, WA 98115
Account Number (or number to reference):
DO YOU WANT CELLULAR/INMARSAT PHONE ACCESS:
Map and Table of Biophysical Transects/Stations
Map and Table of Juvenile Habitat Transects/Stations
Gear Deployment Procedures