Well, because of the wind and the inevitable waves that resulted we couldn’t do any calibration today. Elliot (in charge of this portion of the project) said it will just have to wait until tomorrow. Even though he is staying on the Foster, he will be transported to the Auk daily to do the prey mapping. Hopefully there is better weather on Monday, the first official day of the cruise, and we can get it done before anything too exciting happens.
I did learn a little about echosounders today and the process of prey mapping, but since it is better explained by someone who actually knows what they are doing, here is more information taken from the 2010 blog:
The acoustic echosounder is towed through the water a little beneath the surface as the ship moves around. The echosounders send out short pulses (or pings like on a submarine in a WWII movie) and then record the echoes that come back to the instrument. This is the same technology that governs how a fish finder or depth sounder on a boat works. However ours are a bit higher tech and can provide us some additional information. If there are enough copepods in the water column, then we can see their echoes on our screeen and can tell (in some cases) how many animals there are (number of animals per cubic meter) and where they’re at (near the surface, near the bottom, or moving from one spot to another). -Joe