Wednesday, March 30, 2016

ScanPot Day 1

Some of the folks I work with have been busy doing field work all winter, but I've been in the office for much of it.  So it was great to get back out on the water after a few months.  And we couldn't have picked a nicer day: sunny, 50 degrees, with <1 foot seas in Buzzards Bay.  A rare treat.

We were out on our first field day for a NFWF-funded project we call "ScanPot."  We're quantifying the efficiency of using sidescan sonar to identify lobster pots on the seafloor in flat-softer bottom (low backscatter) and rough-harder bottom (high backscatter).  We're partnering with a commercial lobsterman on the project and using his boat.

We're using a Klein3000 200/355 kHz sidescan we borrowed from the wonderful folks at MIT Seagrant.  We collect data onto a laptop running SonarPro v. 12.  We collected both the high and low resolution imagery, but only looked at the high resolution imagery on the survey.

Here's a shot of the Klein. We used a hand cable since we were in shallow water and only doing a few hours of survey work.
Here's our tow set up -l bracket aluminum on cylindrical posts.
Here's a stack of 4 lobster pots
Here's a lobster pot as imaged by the sidescan (it's the square white box near the bottom of the red circle)

We were hoping to image the pots at a 75 meter range, but beyond 50 meters the resolution was too compromised.  So we'll have to do our full surveying at a 50 meter range.

No comments: