Dataset: salmon_biodata
Deployment: GP0207-01

salmon length, weight, sex, stomach data, 2001-2004

Principal Investigator:

Alex C. Wertheimer (National Oceanic and Atmospheric Administration - Alaska Fisheries Science Center, NOAA-AFSC-Auke)

Co-Principal Investigator:

Edward D. Cokelet (National Oceanic and Atmospheric Administration, NOAA-PMEL)

Edward V. Farley (National Oceanic and Atmospheric Administration - Alaska Fisheries Science Center, NOAA-AFSC-Auke)

Scientist:

Jamal Hasan Moss (University of Washington, UW)

Contact:

Jamal Hasan Moss (University of Washington, UW)

BCO-DMO Data Manager:

Nancy Copley (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

U.S. GLOBEC Northeast Pacific (NEP)

Deployment Synonyms:

GP0201

Data URL:

https://www.bco-dmo.org/dataset-deployment/452534/data

Expand/Collapse All

Description

GLOBEC 2000: Factors Affecting the Distribution of Juvenile Salmon in the Gulf of Alaska
J. Helle (NMFS/AFSC, Auke Bay Laboratory)
E. D. Cokelet (Pacific Marine Environmentla Laboratory),
E. V. Farley, Jr. (NMFS/AFSC, Auke Bay Laboratory),
A. B. Hollowed (NMFS/AFSC),
P. J. Stabeno (Pacific Marine Environmental Laboratory)

"Remarkable changes in atmospheric, oceanic and biological conditions have occurred in recent decades in the North Pacific Ocean including declines in the marine survival of some salmon stocks. Fishery scientists generally agree that in the first few months after leaving freshwater, salmon survival and growth are linked to oceanic variability. The purpose of this research is to focus National Marine Fisheries Service studies on the GLOBEC region, augment oceanographic measurements and determine what biological and physical factors influence the distribution of juvenile salmon. Three general hypotheses are explored in this proposal: (1) juvenile salmon prefer the buoyancy-driven Alaska Coastal Current (ACC) at the head of the Gulf of Alaska, (2) they associate with oceanic temperature, salinity, current and prey fields, and (3) they migrate landward of Kodiak Island in the ACC rather than seaward in the Alaskan Stream. Annual, summer cruises aboard a chartered fishing vessel will catch juvenile salmon on 10 transects between Yakutat Bay and Kodiak Island. The vessel will be outfitted with a thermosalinograph to measure sea-surface temperature and salinity, and with an Acoustic Doppler Current Profiler (ADCP) - each operating continuously for fine-scale resolution. Modeled tidal currents will be removed from ADCP measurements to reveal the mean flow fields. At each trawl site, temperature and salinity profiles will provide water-column properties, and bongo-net hauls will give zooplankton distributions. Stomach samples from juvenile salmonids will be analyzed in the laboratory for diet composition and compared with zooplankton distributions. Analysis of salmon otoliths for hatchery thermal marks and Genetic Stock Identification techniques will be used to determine the home stream of hatchery and wild stocks in the Gulf of Alaska and their distribution with respect to oceanographic regimes. Retrospective analysis of catch per unit effort versus oceanographic and prey factors will reveal what affects the distribution of pink, chum, coho and sockeye salmon in the study region. Proxies for bio-physical factors will be developed and compared with salmon-run size."(project proposal)

Data Collection Details:
Types: CTD profiles, ADCP profiles of ocean current, juvenile salmonid catch statistics from trawls, salmonid stomach samples analyzed for diet composition, salmonid otolith analyses, Genetic Stock Identification, zooplankton distributions from bongo-net hauls
Platform: Chartered fishing vessel
Spatial extent: 10 transects perpendicular to the coast between Yakutat Bay and Kodiak Island
Temporal extent: ~2 weeks each July-August of 2001-2004.

Methods & Sampling

Dataset acquisition description

Fish samples were collected with a 198-m-long mid-water rope trawl with hexagonal mesh wings and body, and a 1.2-cm mesh liner in the codend (Fig. 2, Table 1). The rope trawl was towed at 3.5 to 5 kt, at or near surface, and had a typical spread of 40-m horizontally and 14-m vertically. All tows lasted 30 minutes and covered 1.5 to 2.8 nautical miles. All fish sampling was done during daylight hours. Sometimes this meant that salmon trawls preceded CTD casts. For reference, sunrise occurred at 06:04 ADT and sunset at 22:27 ADT on 1 August 2003 at 58o N. Alaska Daylight Time (ADT) is 8 hours earlier than Greenwich Mean Time (GMT).

Station map from the GP0108 cruise report.

Data Processing Description

Dataset Processing Description

Salmon and other fishes were sorted by species and counted. Standard biological measurements including fork length, body weight and sex. Scale samples from a preferred area (to document age and growth) were taken from subsamples of all salmon species. Subsamples of juvenile pink (Oncorhynchus gorbuscha), chum (O. keta), and sockeye (O. nerka) salmon were frozen whole for laboratory analyses of food habits, otolith hatchery thermal marks (pink and chum salmon), and genetic analysis (chum salmon). Tissues and otoliths were also saved from immature and maturing chum salmon to determine stock distribution and migration of these salmon. All other fish species were counted; juvenile rockfish (Sebastes spp.) and sablefish (Anoplopoma fimbria) were frozen whole for laboratory analyses.

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-0109078	NSF Division of Ocean Sciences
unknown NEP NOAA	National Oceanic and Atmospheric Administration

Instruments

Midwater Trawl

Supplied Description:

Fish samples were collected with a 198-m-long mid-water rope trawl with hexagonal mesh wings and body, and a 1.2-cm mesh liner in the codend. The rope trawl was towed at 3.5 to 5 kt, at or near surface, and had a typical spread of 40-m horizontally and 14-m vertically.

Instrument Type

Generic Name: Midwater Trawl

Acronym: TrawlMid

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/23/

Generic Description:

A mid-water or pelagic trawl is a net towed at a chosen depth in the water column to catch schooling fish such as herring and mackerel. Midwater trawl nets have very large front openings to herd schooling fish toward the back end where they become trapped in the narrow "broiler". The sides of the deployed net are spread horizontally with two large metal foils, called "doors," positioned in front of the net. As the trawler moves forward, the doors, and therefore the net, are forced outward, keeping the net open.
This instrument designation is used when specific make and model are not known.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
year	year, reported as YYYY, e.g. 1995	dimensionless	year
day_local	day of month, local time	dimensionless	day_local
month_local	month of year, local time	dimensionless	month_local
yrday_local	Local day and decimal time, as 326.5 for the 326th day of the year, or November 22 at 1200 hours (noon).	dimensionless	yrday_local
haul_id	First four numbers represent year, second four numbers represent haul number.	dimensionless	haul_id
sta_id	Station identification.	dimensionless	sta_id
transect	Transect name.	dimensionless	transect
lat	Latitude, in decimal degrees, North is positive, negative denotes South.	decimal degrees	lat
lon	Longitude, in decimal degrees, East is positive, negative denotes West.	decimal degrees	lon
depth_w	water depth	meters	depth_w
species_common_name	common name of fish species	dimensionless	species
maturity	Status of maturity: adult (A), juvenile (J), immature (I).	dimensionless	stage
length_froz	length of frozen fish from front tip to fork of tail	?	length
length_wet	length of wet fish	?	length
weight_froz	weight of frozen fish	grams	weight
weight_wet	weight of wet fish - pre-frozen	grams	weight
sex	Male (m), Female (f), Immature (i)	dimensionless	sex
stomwt_full	Stomach weight while full.	grams	no_bcodmo_term
stomwt_empty	empty stomach weight	?	no_bcodmo_term
sealice	number of parasitic sea lice found on body	dimensionless	no_bcodmo_term
comments	comments pertaining to sample	dimensionless	comment

Database

Contribute Data

Dataset: salmon_biodata
Deployment: GP0207-01

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: salmon_biodataDeployment: GP0207-01

Dataset acquisition description

Dataset Processing Description

Dataset: salmon_biodata
Deployment: GP0207-01