NOAA Teacher at Sea
Mark Wolfgang
Aboard NOAA Ship Reuben Lasker
April 11 – April 22, 2017
Mission: Spring Coastal Pelagic Species (Anchovy/Sardine) Survey
Geographic Area of Cruise: Pacific Ocean
Date: April 12, 2017
Weather Data from the Bridge:
Lat: 35o 21.1’ N Long: 121o 26.9’ W
Overcast, rainy with quite a bit of fog
Temperature: 14oC (56oF)
Wind speed: 9.26 knots
Barometer: 1015.17 mbar
Visibility: Very limited
Scientific and Technology Log:
Last night/this morning, we did our first two trawls. These two trawls were kind of “blind” because they had not started doing acoustic trawls. I think I am starting to get the hang of how things happen during a trawl, which I know will be put to the test tonight.
As the net is pulled in, a team goes out and removes the camera from the net. The camera is used to monitor the net during the trawl, as well as monitoring the MMED (Marine Mammal Excluder Device) which records animals and their condition as they encounter the metal bars and are excluded through the opening in the top portion of the net. The deck crew continues to pull in the net. The organisms collected in the end of the net are put into buckets and brought into the wet lab. The first trawl had a small sunfish in the catch, but I missed it because I was putting my foul-weather gear on.
The organisms are dumped onto a table and sorted. After sorting, the organisms are put on the scale and the mass is recorded. The number and type of fish were recorded. Both trawls had mostly pyrosomes (a colonial tunicate) and market squid. I have taught about tunicates in my zoology class, but never knew they were so common in the Pacific Ocean. Other than the pyrosomes and squid, the two trawls contained some lantern fish, several red pelagic crabs, and some other very small fish as well as a moon jelly.
Since we had no sardines or anchovies to process, we focused our time on the market squid. A random sample of 50 squid are taken. For each squid, we measure the length of the mantle, place the squid on a balance and record the mass. If the squid were larger than 75 mm, the squid was given a tag and placed in a bag. The squid smaller than 75 mm are all placed together in a bag.
It was impressive how all team members got right to work and functioned like a well-oiled machine. I am also impressed with how all individuals think of safety first. Starting at sunrise, they began doing acoustic trawls, so we may have better luck catching sardines and anchovies tonight.
Personal Log:
I have enjoyed my first days on the Reuben Lasker. The crew and science team have been very accommodating and welcoming. I am trying to be helpful and not get in the way. My roommate is a UAS drone pilot, but the weather has not been good enough to fly today – it is quite foggy and rainy and the seas are choppy. I hope I get a chance to see it fly sometime soon. I am trying to get used to the sleeping schedule and since I couldn’t sleep this morning, I took a little tour today and went to the bridge and spoke to some of the crew on the bridge as well as the Commanding Officer (CO). They showed me around a little and described some of the different navigational equipment. The chief electrician showed me around the computers in the acoustic lab. It is crazy to see all of the technology and to hear about how they handle all of this data with limited internet access on the boat. I am so pleased that everyone was been so friendly. The food has been great (we had an incredible crème brulee last night) and I have not been sea sick so far.
Did you know?
Pyrosomes are colonies of hundreds of individuals known as zooids. These zooids are joined by a gelatinous tunic and work in unison to propel the colony through the water.