From Ed Lavender on gear types (3)

[AquaAuma]

WCTRI. My understanding is that the WCTRI surveys use a Poly Nor’Eastern trawl. In the dataset, the gear types listed for this survey are 160, 162, 170 and 172. I have searched high-and-low for the definitions of these numbers, but I can’t find anything. Are you able to provide any clarity here?

@zoekitchel @mpinsky

[AquaAuma]

@James-Thorson-NOAA @mpinsky

[mpinsky]

@James-Thorson-NOAA , for clarification, this is the West Coast Triennial survey. Do you know the gear types?

[James-Thorson-NOAA]

I responded by email (which I saw first) but see description from TM below

The standard RACE high-opening Nor'eastern trawl, constructed of polyethylene mesh and equipped with rubber bobbin roller gear, was used aboard both vessels throughout the 2001 survey (Fig. 1). This trawl has a 27.2 m headrope and a 37.4 m footrope. All trawls were rigged consistently to RACE survey gear standards employing triple 55 m dandylines (1.59 cm steel cable) connected to each wing and fished with 2.1 × 1.5 m steel V-doors weighing approximately 567 kg each.

[mpinsky]

This document has gear codes on pg. 24: https://repository.library.noaa.gov/view/noaa/31570

The relevant ones for us:

• 160: Nor’eastern trawl, 90’ headrope, 105’ footrope. 22 13”Diameter plastic floats on headrope, 5” mesh in body, 3.5” Mesh in intermediate and codend. Mean effective path width = 13.44M, range 11.6M-16.5M. Mean vertical opening = 9.2M, range 8.2M-9.9M.
• 162: Same as 160, but #72 thread mesh used in trawl belly section.
• 170: Modified nor’eastern trawl, polyethylene with nylon codend. 92’ Headrope is 5/8” wire rope wrapped with 3/8” 3-strand polypropylene. 82.5’ Footrope is 1/2” wire rope wrapped with 1/2” 3-strand polypropylene. 21 12”Diameter floats on headrope. Approximate sampling dimensions: 64’ width, 18’ vertical opening when used with accessories 58. (Used on morning star cr.841.)
• 172: Poly-nor’eastern, four seam, hard bottom, high rise rock-fish trawl constructed of polyethylene. 27.2M (89’1”) headrope is galvanized wire rope wrapped with 3-strand polypropylene. 37.4M (122’8”) footrope: 24.7M (81’7”) middle section is galvanized wire rope wrapped with polypropylene, connected to lower “flying wings” with 6.4M (19’6”) sections of wire rope with rubber disks. Codend is 8.9Cm (3 1/2”) stretch mesh poly, liner of 3.2Cm (1 1/4”) nylon, 315 meshes circumference and 200 meshes deep.

@jepa , could you add this to our gear information for WCTRI?

[James-Thorson-NOAA]

Thanks Malin! That's a new TM to me, but very useful to know about :)

[jepa]

Added this information to the summary file. This is it right? Just confirming there is not coding adaptation needed to be done @mpinsky

[mpinsky]

@jepa , the summary file (does it describe gear types?) and the metadata_docs/README.md would both be good.

[jepa]

Cool. I'm adding it to the summary file of each survey as a "special note"