Dataset: Scup and windowpane flounder expanded lengths
Deployment: Elizabeth_and_Katherine-trip1

Scup and windowpane flounder expanded lengths table

Principal Investigator:

Emerson C Hasbrouck (Cornell University, Cornell)

Contact:

Kristin Gerbino (Cornell University, Cornell)

BCO-DMO Data Manager:

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

Project:

Small Mesh Fishery Bycatch Reduction in the Southern New England/Mid-Atlantic Windowpane Flounder Stock Area (Windowpane Bycatch)

Data URL:

https://www.bco-dmo.org/dataset-deployment/686710/data

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Description

Methods & Sampling

Dataset acquisition description

Hauls were made in southern New England marine waters encompassing approximately 2000 square miles extending from Point Judith, RI in the west to Martha’s Vineyard, MA in the east and extending south to include Rhode Island Sound and portions of the Atlantic Ocean.

Subsamples of the catch were taken during each tow for length frequency distribution analysis. For each tow, 100 individual length measurements were taken for scup and windowpane flounder. All fish were measured if there were less than 100 per tow. The subsample length frequencies were expanded to the entire catch to determine the length frequency distribution for the catch. For each tow, the total catch numbers at length were calculated as the subsample numbers at length multiplied by the species-specific ratio of catch weight to subsample weight. Catch numbers were calculated for each net as the sum of the expanded numbers at length per tow.

The methodology is available in the final report (pdf). See Supplemental Files section.

Deployment-specific acquisition description

This dataset combines trip 1 from Katherine & Elizabeth and Sea Breeze Too.

Data Processing Description

Dataset Processing Description

BCO-DMO Processing Notes:
- added conventional header with dataset name, PI name, version date
- modified parameter names to conform with BCO-DMO naming conventions
- reduced number of significant digits of ratio (wgt_total_to_wgt_subsample) due to math precision rules

More information about this dataset deployment

Funding

Award Number	Funding Source
15-033	NorthEast Consortium

Instruments

Trawl_custom

Supplied Name:

Supplied Description:

Experimental net with the large mesh belly panel and small mesh typical of that used in scup fishery along the East Coast of the US. The nets used for this project were 286 x 16cm, 4-seam, 3-bridle standard otter trawls. The 286 x 16cm refers to the circumference of the fishing circle (286 meshes around of 16 cm mesh to form the circle) and nets of this size are appropriate for vessels with horsepower in the range of 400hp to 550hp. The net was constructed with 16cm (full mesh) webbing in the wings and jibs. The bunt and the 1st bottom belly were constructed from 12 cm mesh. The top square, top bellies, and the side panels were constructed from 8cm Dyneema webbing. The last belly section, top, and bottom were 6cm PE webbing. The codend was constructed of 5" regulation mesh used in the scup fishery. Flotation for this trawl was provided by 48 -8" floats mounted on the headrope. The sweep of the trawl was constructed of 2-3/8" and 3" rubber discs on wire rope. The sweep was comprised of three pieces totaling 2400cm or 78.72 feet in length. The headrope height was approximately 16 feet high. This net was then modified by Jon Knight of Superior Trawl to include the LMBP. The large mesh panel for this project was made from 5mm poly webbing and the mesh size was 80cm or approximately 32 inches knot-center to knot-center diamond mesh. The actual panel was 2 meshes deep and was sewn into the standard 12cm (5”) mesh of the 1st bottom belly using a "saw-toothing" technique. Similar to the SNECRI project, this results in an effective area for fish escapement of 3 full 32 inch meshes, or an opening in the belly of the net that is approximately 8 feet deep from front to back. The LMBP attached approximately 1 foot (2.5 meshes/12cm) behind the footrope and extended widthwise across the entire belly of the net (from gore to gore) for 30 meshes of 32 inch diamond mesh.

Instrument Type

Generic Name: Trawl_custom

Acronym: Custom Trawl

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

Generic Description:

A net towed through the water column designed to sample free-swimming nekton or fish, varies in design depending on the research project.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
trip	trip number	unitless	cruise_id
tow	tow number	unitless	tow
treatment	Control net or net with large mesh belly panel	unitless	treatment
species	fish species: scup or windowpane flounder	unitless	species
count	Number of fish measured in subsample	fish	count
wgt_fish_avg	average weight of individual scup or windowpane flounder calculated by dividing 'Count' by 'Total Pounds'	pounds	weight
sp_catch_lb	species specific total catch weight	pounds	weight
wgt_subsample	weight of species-specific subsample	pounds	weight
wgt_total_to_wgt_subsample	ratio of the species-specific total catch weight to the subsample weight	pounds	weight
len_4cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_5cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_6cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_7cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_8cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_9cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_10cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_11cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_12cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_13cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_14cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_15cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_16cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_17cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_18cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_19cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_20cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_21cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_22cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_23cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_24cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_25cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_26cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_27cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_28cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_29cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_30cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_31cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_32cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_33cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_34cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_35cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_36cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_37cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_38cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight
len_39cm	weight of fish in this length bin for entire catch; calculated by multiplying fish in length bin from the length frequency dataset by the species specific catch (wgt_total_to_wgt_subsample)	fish	weight

Database

Contribute Data

Dataset: Scup and windowpane flounder expanded lengths
Deployment: Elizabeth_and_Katherine-trip1

Dataset acquisition description

Deployment-specific acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: Scup and windowpane flounder expanded lengthsDeployment: Elizabeth_and_Katherine-trip1

Dataset acquisition description

Deployment-specific acquisition description

Dataset Processing Description

Dataset: Scup and windowpane flounder expanded lengths
Deployment: Elizabeth_and_Katherine-trip1