Cathrine Prenot: A Fish Tale, Too Big to Fail. July 18, 2016

NOAA Teacher at Sea
Cathrine Prenot
Aboard the Bell M. Shimada
July 17-July 30, 2016

 

Mission: 2016 California Current Ecosystem: Investigations of hake survey methods, life history, and associated ecosystem

Geographical area of cruise: Pacific Coast from Newport, OR to Seattle, WA

Date: July 18, 2016

Weather Data from the Bridge:
Lat: 45º19.7 N
Lon: 124º21.6 W
COG: 11.2
Speed: 17.1 knots
Air Temp: 16.4 degrees Celsius
Barometer (mBars): 1019.54
Relative Humidity: 84%

Science and Technology Log

It is exciting to be out to sea on “Leg 2” of this cruise! The official title of our research is “2016 California Current Ecosystem: Investigations of hake survey methods, life history, and associated ecosystem.” One of the key portions of this leg of the trip is to collect data on whether or not a piece of equipment called the “Marine Mammal Excluder Device” (MMED) makes any difference in the fish lengths or the species we catch. Here is how it works (all images from Evaluation of a marine mammal excluder device (MMED) for a Nordic 264 midwater rope trawl):

The catch swims towards the codend of the net and encounters the MMED
The catch swim towards the codend of the net and encounter the MMED
The catch encounters the grate; some go through the grate while others escape the net through the hatch (shown by the orange buoy).
Some of the catch go through the grate (to the codend) while others escape the net through the hatch (shown by the orange buoy).

Why is this important?  For example, if all of one type of fish in a trawl escape through this MMED, we would be getting a different type of sample than we would if the equipment was off the nets.  Our lead scientist, Dr. Sandy Parker-Stetter explained: “If all the rockfish go out the top escape panel, how will we know they were there?”   To collect data on this, we will be doing a lot of trawls—or fishing, for those non-sea faring folk—some with the MMED and others without it. These will be small catches, we need about 300-400 fish, but enough to be able to make a determination if the equipment effect the data in any way.

We have done a few trawls already, and here are some of the photos from them:

'Young of the Year' Hake
‘Young of the Year’ Hake
Pacific Hake sample
Pacific Hake sample
Wanted: must love fish. And science.
Wanted: must love fish. And science.

All of this reminds me of why we are so concerned with accurately estimating the population of a little fish. To illustrate, let me tell you a story—a story of a fishery thought too big to fail—the Great Banks Atlantic Cod fishery. Why don’t you click on Issue 2 of Adventures in a Blue World: A Fish Tale, Too Big to Fail.

Adventures in a Blue World, CNP. A Fish Tale: Too Big to Fail
Adventures in a Blue World, CNP. A Fish Tale: Too Big to Fail

Cod populations decreased to such a degree (1% of previous numbers), that the Canadian Government issued a moratorium on Cod fishing in 1992.  Our mission—to investigate of hake survey methods, life history, and associated ecosystem—is designed to prevent such a devastating result. We don’t want Hake or other species to go the same route.

Atlantic Cod circa 1920s: from here

Personal Log

We left the left the dock on Sunday at 1145, and made our way under the Newport Bridge and out to sea. It was really wonderful to watch the ship leave the harbor from way up on the Flying Bridge—the top-most deck of the ship. There are four tall chairs (bolted to the deck) at the forward end of the deck, an awning, and someone even rigged a hammock between two iron poles. It is rather festive, although again, there were no drinks with umbrellas being brought to us.

View of Newport, OR from the flying bridge of the Shimada
View of Newport, OR from the flying bridge of the Shimada

I didn’t have any problems with seasickness on my last voyage, but I did take some meds just in case. One of the researchers said that he doesn’t take any meds any more, he just gets sick once or twice and then feels much better. If you are interested, here is a link to my previous cartoon about why we are sea-sick, and how and why ginger actually works just as well as other OTC drugs. All I can say now is that I’m typing this blog in the acoustics lab, and the ship does seem to be moving rather alarmingly from fore to aft–called pitching.  Maybe I should find a nice porthole. In the meanwhile, you can read “Why are we seasick.”

 

Did You Know?

The end of the fishing net is called the codend.  Who knew?  This and many more things can be learned about fishing from reading this handy reference guide.

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