Dataset: Bigelow Bight fish and lg inverts
Deployment: NEC-MD2001-2

Benthic habitat correlates of juvenile fish - large inverts & fish

Principal Investigator:

Michele Dionne (Wells National Estuarine Research Reserve)

BCO-DMO Data Manager:

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

Project:

Northeast Consortium: Cooperative Research (NEC-CoopRes)

Data URL:

https://www.bco-dmo.org/dataset-deployment/452419/data

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Description

Benthic habitat correlates of juvenile fish distribution in the Bigelow Bight and adjacent estuaries: linkages between fish, habitats, substrate and human activity

Additional Project Participants:
Vincent Balzano, Commercial Fisherman, F/V North Star
Richard MacKenzie, Researcher
Scott Orringer, Researcher
Jeff Reed, Commercial Fisherman
Kenneth Young, Commercial Fisherman
Marshall Alexander, Commercial Fisherman, F/V Dee Dee Mae II

This study represents a collaboration between researchers and members of the Gulf of Maine fishing industry to survey juvenile groundfish distribution and abundance along transects from estuarine through inner shelf areas of the Bigelow Bight. The project characterizes associated substrate and prey availability in order to determine fisheries habitat resources with the region. The project features the use of a sediment profile imager (known as a SPI camera), a device which takes photos of substrates and associated organisms both from a surface and from a profile view to depths up to 1 ft. This technique was combined with traditional research sampling methods for fish (small mesh trap nets, beam trawls, and variable mesh gill nets) and benthos (Ponar grab sampler). The survey design compared fish, benthos and substrates between estuarine, nearshore and offshore areas, including sites within these zones that have been altered by human activities (i.e. dumping of dredge material, outfall of treated sewage, and bottom trawling). Traditional cod spawning and feeding grounds and a closed area (Jeffrey's Ledge) are included in the survey. Results of the study will provide much needed data to determine estuarine and inner shelf fish habitat associations, the food resource value of these habitats, and their response to current and previous human alterations.

Methods & Sampling

Dataset acquisition description

Data Processing Description

Dataset Processing Description

All bottom samples to date have been sieved through a 1mm mesh screen and preserved in a Rose Bengal/70% ethanol mixture.

More information about this dataset deployment

Funding

Award Number	Funding Source
unknown NEC-CoopRes NEC	NorthEast Consortium

Instruments

Beam Trawl

Supplied Name: Trawl

Supplied Description:

2 meter beam trawl

Instrument Type

Generic Name: Beam Trawl

Acronym: Beam trawl

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/24/

Generic Description:

A beam trawl consists of a cone-shaped body ending in a bag or codend, which retains the catch. In these trawls the horizontal opening of the net is provided by a beam, made of wood or metal, which is up to 12 m long. The vertical opening is provided by two hoop-like trawl shoes mostly made from steel. No hydrodynamic forces are needed to keep a beam trawl open. The beam trawl is normally towed on outriggers, one trawl on each side.

While fishing for flatfish the beam trawl is often equipped with tickler chains to disturb the fish from the seabed. For operations on very rough fishing grounds they can be equipped with chain matrices. Chain matrices are rigged between the beam and the groundrope and prevent boulders/stones from being caught by the trawl. Shrimp beam trawls are not so heavy and have smaller mesh sizes. A bobbin of groundrope with rubber bobbins keeps the shrimp beam trawl in contact with the bottom and gives flatfish the opportunity to escape.

Close bottom contact is necessary for successful operation. To avoid bycatch of most juvenile fishes selectivity devices are assembled (sieve nets, sorting grids, escape holes). While targeting flatfish the beam trawls are towed up to seven knots, therefore the gear is very heavy; the largest gears weighs up to 10 ton. The towing speed for shrimp is between 2.5 and 3 knots.

(from: http://www.fao.org/fishery/geartype/305/en)

Flounder Trap

Supplied Description:

fish trap

Instrument Type

Generic Name: Flounder Trap

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/63/

Generic Description:

Based on an historical design used previously in the Gulf of Maine to target Winter Flounder, this experimental trap is a converted lobster trap fitted with a standard crab hoop acting as one long entrance. The crab hoop measures 8 inches across and 2 1/2 inches in height and it was hoped that this hoop would allow flatfish, crabs and some finfish to enter while excluding most lobsters. These traps were built by Kelo Pinkham and Jim Lowe, from Boothbay, Maine. Collapsible square fish traps are also available commercially for eel, crawfish and flounder.

Gillnet

Supplied Description:

Instrument Type

Generic Name: Gillnet

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/65/

Generic Description:

Gillnetting uses curtains of netting that are suspended by a system of floats and weights; they can be anchored to the sea floor or allowed to float at the surface. A gillnet catches fish by their gills because the twine of the netting is very thin, and either the fish does not see the net or the net is set so that it traps the fish.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
year	year, e.g. 2009.		year
site	geographic location of sampling		no_bcodmo_term
inst	instrument used to collect or process data		instrument
month_local	month of year, local time		month_local
day_local	numerical day of month, local time		day_local
yrday_local	local day and decimal time, as 326.5 for the 326th day, or November 22 at 1200 hours (noon)		yrday_local
lat_end	latitude at end time of measurement (south in negative)	decimal degrees	lat_end
lat_start	latitude at starting time of measurement (west is negative)	decimal degrees	lat_start
lon_end	longitude at end time of measurement (west is negative)	decimal degrees	lon_end
lon_start	longitude at starting time of measurement (west is negative)	decimal degrees	lon_start
transect_num	transect number, as when a ship crosses an area repeatedly.		transect
depth_start	starting sample depth	meters	depth
depth_end	ending sample depth	meters	depth
taxon	taxonomic group or entity. This may be a family, class, genus, species, common name, etc.		taxon
number	number of organisms counted/observed		number
length	length of specimen	millimeters	length
comments	free text comments, may only have meaning to submitting PI		comment
time_end	ending time of observation, local time , 24 hour clock		time_end_local
time_start	starting time of observation, local time, 24 hour clock		time_start_local

Database

Contribute Data

Dataset: Bigelow Bight fish and lg inverts
Deployment: NEC-MD2001-2

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: Bigelow Bight fish and lg invertsDeployment: NEC-MD2001-2

Dataset acquisition description

Dataset Processing Description

Dataset: Bigelow Bight fish and lg inverts
Deployment: NEC-MD2001-2