Dataset: herring spawing grounds_acoustic locations
Deployment: NEC-JA2005-1

This project was designed to acoustically monitor the locations, timing, and biomass levels of prespawning and spawning aggregations of Atlantic herring on significant "sentinel" spawning grounds. The western portion of the Gulf of Maine (Figure 4), which encompasses Jeffreys Ledge, Scantum Basin, and the coastal waters from Cape Ann, MA to Cape Porpoise, ME was chosen for a trial of this sentinel survey approach. The long-term goal is to extend the sentinel survey model to additional areas in the nearshore Gulf of Maine. Specific information collected on the timing and locations of spawning Atlantic herring will allow comparison with historical distributions and abundance of spawning Atlantic herring and provide insight into the relative importance of this region for spawning Atlantic herring.

Methods & Sampling

Dataset acquisition description

Project Reports:
Herring Acoustic Survey (Year 6) Final Report - July 2007 (Annala_05_HerringAcoustic_FINAL.pdf)

Data Processing Description

Dataset Processing Description

DATA

Three sets of data files are included with the project report to be posted on the Northeast Consortium's Fisheries and Oceans Database:

1. CTD cast data: These files include the cruise or leg number, cast number, date, time, latitude, longitude, depth (m), temperature (°C), salinity (ppt) and fluorescence (mg/m3).

*2. (these data) Survey transect data - These files include ping number, year, month, day, time, latitude and longitude.

3. Herring biological sample data - These files include date, time, latitude, longitude, length (mm), weight (g), sex, ICNAF maturity stage and gonad weight (g).

The raw acoustic data files will not be submitted since it can only be interpreted by users with specialized analysis software. GMRI is presently aware of only two other groups that possess the software necessary to view the data collected, both part of the Canadian Department of Fisheries and Oceans. The data are therefore unsuitable for posting on a general access database such as the Northeast Consortium's Fisheries and Oceans Database.

A technical problem was encountered while collecting the CTD surface data files. No date or time was recorded; therefore, they can not be matched to any positions from the survey transect data. These files will not be submitted.

More information about this dataset deployment

Funding

Award Number	Funding Source
NA05NMF4721057	National Oceanic and Atmospheric Administration

Instruments

Echo sounder - single-beam

Supplied Name: Echo Sounder

Supplied Description:

FEMTO Electronics Limited
DE9320 Digital Echosounder interfaced with a 75 kHz hull mounted transducer.

Instrument Type

Generic Name: Echo sounder - single-beam

Acronym: Echo Sounder SB

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/156/

Generic Description:

A single-beam echo sounder is an instrument that measures water depth at a single point below the platform by timing pulses of sound reflected on the seafloor. The echo sounder transmits and receives sound, accurately measuring the time it takes to leave the sounder, reach the bottom and return to the sounder. It then converts this information into digital or graphic representations of the bottom depth and relief.
The average echo sounder consists of a transmission and reception unit that sends sound signals through the water, receives and decodes information and converts that information into either a graphic or visual form. Attached to the receiver is a transducer that acts as a microphone and a speaker under the water. Sound waves travel at approximately 1500 m/s through the water dependent on water temperature". more from LMS Technologies

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
year	year		year
yrday_local	local year day		yrday0_local
day_local	local day		day_local
month_local	local month		month_local
time_local_start	local start time		time_local
lat_start	latitude at start of transect	decimal degrees	lat_start
lon_start	longitude at start of transect	decimal degrees	lon_start
lat_end	latitude at end of transect	decimal degrees	lat_end
lon_end	longitude at end of transect	decimal degrees	lon_end
cruiseid	sequential cruise number for this project		cruiseid
transect	transect number		transect
time_local_end	time at end of transect		time_local

Database

Contribute Data

Dataset: herring spawing grounds_acoustic locationsDeployment: NEC-JA2005-1

Dataset acquisition description

Dataset Processing Description

Dataset: herring spawing grounds_acoustic locations
Deployment: NEC-JA2005-1