Northwest Fisheries Science Center

2017 West Coast Groundfish Bottom Trawl Survey

This portal tracks the 2017 groundfish survey conducted on chartered West Coast fishing vessels by the Fisheries Research Survey (FRS) Team from NOAA's Northwest Fisheries Science Center. During the first half of the survey (May - July) we will conduct sampling from onboard the F/V Excalibur and the F/V Last Straw. The vessels are relatively small (65 - 76 ft in length) and usually host three scientists: a chief scientist from FRS and two back deck biologists. Many of the back deck biologists are volunteers without whose assistance we could not conduct the survey. The vessel personnel includes the Captain, two crewmembers and sometimes a night watch person. Follow us as we use trawling and oceanographic sampling to learn about the California Current ecosystem and the health of many West Coast fish populations. The survey traverses the entire area from U.S.-Canada to U.S.-Mexico at depths from 55 m to 1280 m twice during the sampling season (May - October). The survey is the primary source of fisheries independent information used in the management of 40+ groundfish along the U.S. West Coast. Although communications are often spotty while the team is at sea, chief scientists will post updates during periodic port calls as the vessels sample throughout the survey season.

test
Excalibur Haul Out Mob
test 3
Galley Table Mob
test 2
Sunrise on the Excalibur

Second Leg of the First Pass of the 2017 West Coast Groundfish Bottom Trawl Survey

By Aaron Chappell
Posted on June 19, 2017


calendar date May 19-29
 

 

Departed from Newport, Oregon on 6/1/2017. Arrived in port in Brookings, Oregon on 6/11/2017. Untrawlable habitat Aaron Chappell, FPC on F/V Last Straw 6/14/2017

The West Coast Groundfish Bottom Trawl Survey collects fishery-independent information on more than 90 groundfish species targeted commercially along the coasts of Washington, Oregon and California. The fishing gear used during the survey primarily targets fish on soft-bottom in low to moderate gradient areas, commonly referred to as “trawlable” habitat. However, we frequently encounter hard-bottom, high relief or high gradient “untrawlable” seafloor types in our randomly selected stations. In these situations, the Captain of the vessel will search our 1.5 by 2.0 nautical mile station cells for a minimum of one hour in hopes of finding trawlable habitat. Each of our stations consists of three cells: primary, secondary and tertiary, so there are three chances of finding a suitable place to tow. If all three cells are searched and no trawlable area found, we refer to that station as “Searched and Dropped,” and it is considered completed in the same sense as a successful tow.

Our charted vessels use a variety of equipment, along with the Captains’ many years of experience, to determine trawlable habitat.

On the chartered West Coast fishing vessel, F/V Last Straw, used during the first half of the survey (May – July) these include:

• Furuno 28/50 kHz echo sounder • Furuno 28 kHz paper echo sounder • Furuno CH14 sonar • Simrad EK60/70/80 echo sounder • Olex navigational and charting software 2D/3D, housing sea floor contours, relief, hardness, hang-ups, obstructions, cable crossings, and operates as an information-sharing cooperative with participating vessels. • WindPlot, Offshore Navigator and Coastal Explorer navigational software programs, housing thousands of hang-ups, obstructions, cable crossings and hard-bottom notations.

On the F/V Excalibur, a second chartered West Coast fishing vessel used during the same time period, these include:

• Furuno 1200 28 kHz echo sounder • Furuno 28 kHz paper echo sounder • Furuno 88 kHz Sonar • Simrad EK80 echo sounder • Olex navigational and charting software 2D/3D, housing sea floor contours, relief, hardness, hang-ups, obstructions, cable crossings, and operates as an information-sharing cooperative with participating vessels. • WindPlot and Globe navigational software programs, housing thousands of hang-ups, obstructions, cable crossings and hard-bottom notations.

Even with the use of the accurate and sophisticated equipment described above coupled with our Captains’ vast knowledge of West Coast habitat and fishing grounds, sometimes there is just no trawlable bottom in our cells to complete a 15-minute (approximately 1/3 to 1/2 mile) tow.

This photo depicts the F/V Last Straw’s Furuno 28/50 kHz echo sounder (bottom) outlining depth, relief, hardness, and fish aggregations, as well and Offshore Navigator software (top) showing vessel position, heading, depth contours and the many marks created during the Captain’s many years of fishing experience. (Photo credit: Aaron C. Chappell/NMFS)

 
More wheelhouse equipment from the F/V Last Straw designed to determine trawlable ground: Bottom - Furuno 28 kHz Paper Sounder commonly referred to as “The Paper Machine” (bottom), which uses a return echo gram to literally burn an image of the seafloor onto a piece of paper. These machines, while outdated, actually can produce higher-quality images than digital echo sounders, and often can show subject hangs such as medium boulders and pinnacles not easily distinguishable by its modern counterparts. Top left – Olex 2D/3D navigation and charting program monitor, outlining our station cells, bottom depth counters, hardness and relief, marks of places to avoid, and other vessels (tied in via AIS Marine Traffic program). Top right - Furuno “Ancient” CH14 Sonar which has a ‘sweeping’ arc from the transducer’s sounder moving an echo beam back and forth. This machine shows seafloor hardness, as well as fish aggregations.(Photo credit: Aaron C. Chappell/NMFS)
An image of Olex, outlining the three cells (red = primary, yellow = secondary, green = tertiary) comprising station 9345. The lines within each cell are the F/V Last Straw’s tracklines as we searched each cell for a tow. This station was a complete “Search and Drop.”
(Photo credit: Aaron C. Chappell/NMFS)

Other highlights from Leg 2:

Excalibur mid-trip fish delivery in Charleston, Oregon of about 3000 pounds. End of trip delivery in Brookings, Oregon of about 3000 pounds. 39 total stations completed: • 39 successful tows • One primary cell searched and deemed untrawlable (successful tow found in secondary cell).

Last Straw 19000 pound tow in 6:50 minutes, before hanging up on hard bottom at the west end of Heceta Bank. Catch consisted of mostly sharpchin rockfish, but also present were canary, yelloweye, bocaccio, silvergray, widow, yellowtail, greenstriped and redstripe rockfishes. Spotted a Layson Albatross offshore of Charleston, Oregon. Mid-trip fish delivery in Charleston, Oregon of about 7200 pounds. End of trip delivery in Brookings, Oregon of about 9000 pounds. 40 total stations completed: • 39 successful tows • 1 hang-up (unsuccessful tow) • 1 “Search & Drop” station, one other primary cell searched and deemed untrawlable (successful tow found in secondary cell). Our Leg 1 and 2 deliveries put us at more than 75,000 pounds of marketable fish delivered on Pass 1!


Tagged: chartered fishing vessels (f/v), first pass, second leg, 2017, west coast groundfish bottom trawl survey

Go to Top


See more blog entries:

July 2017