Science for Everyone

collaborative research

Desperately Seeking Spat Bags

Some of the bags were completely covered in fast growing seaweed!

Dripping with muddy water and covered with tiny dancing skeleton shrimp, we spent the day searching for and hauling up lines of spat bags. Cait deployed them this past October, so they have been collecting scallop larvae for the past 9 months. A spat bag is constructed of 2 layers of mesh; the outside green layer having very small netting that only larval stage scallops can enter and exit through, and the inside blue layer with larger netting that they can attach and grow on. 5 bags are tied to a line with a cement block on one end and buoys on the other, suspending them at different depths throughout the water column. Soon, we’ll count all the scallop spat in the bags to gain an understanding of how many scallops are entering these areas and how much settlement might be occurring around Muscle Ridge. The bags don’t select for species, so we’re sure to find lots of little clams and mussels as well. 

Keeping the pile of spat bags cold and wet with ocean water

It takes a whole team of eyes to hunt down the right color in the sea of buoys.

Lobstermen generally don’t leave their traps out during the winter and you can see why. The buoys were harder to spot with the colors washed off and some of the bags looked more like we had undertaken seaweed aquaculture! Luckily our fantastic captain, Skip, had a knife handy to clean the outside of the bags as we hauled them up. Strong winter storms can also push the cement blocks across the ocean floor, far away from the GPS point where they were dropped, making it a challenge to find them again. In the end, we recovered 5 of the 12 lines, which luckily included all 3 lines that had the HOBO temperature loggers tied to them! To keep them wet and out of the hot sun, we covered them in burlaps sacks soaked in seawater. After multiple transfers in and out of the water, the spat bags made it on the boat out to Hurricane Island, where we’ll start counting those adorable little scallops.

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The Height of Our Scallop Research Season

This summer has been not only busy on-island with student programs, but also a busy field season collecting data for our collaborative scallop research project. In July 2014, we were awarded a grant administered by Maine Sea Grant with funding from the Maine Community Foundation and the Broad Reach Fund. In early August, we started conducting our second year of dive surveys on Muscle Ridge and Ocean Point.  So far we have completed a total of 16 dive surveys on the Ocean Point scallop closure (you can read more about how this project has been set up here), and surrounding area to assess scallop abundance and to collect samples. These surveys have been conducted with the help of scientists from the Maine Department of Marine Resources and from our HIF science advisor, Dr. Rick Wahle's Lab based at the University of Maine's School of Marine Sciences. I've also been able to work alongside Susie Arnold, the Island Institute's marine scientist, to dive on Muscle Ridge. We've completed 8 sites so far and are hoping to get a few more days of diving in before fall officially arrives!

On September 11, 2014, a crew from Dr. Kevin Stokesbury's lab based at the University of Massachusetts at Dartmouth arrived in Maine and set up their drop camera rig on Tad Miller's dragger, F/V Julie Ann in Tenants Harbor. We then did three days of drop camera surveys on Muscle Ridge. To identify the sampling stations, we laid a 200 m x 200 m grid over the survey area and marked the center of each cell. We would then steam to the latitudinal and longitudinal coordinates of that center point and drop the camera to the bottom to take footage of the life below.  Fortunately, we did not have any major technical difficulties and were able to increase the number of sites we sampled this year as compared to October 2013 where we lost a cable which limited our ability to sample deeper sites. 

This weekend (September 19 - 21, 2014), I will work with one of our industry partners to set the spat bags out which will then be collected and processed next June. I hope we are able to wrap up the field work by the end of October then on to analysis and preparing for the 2015 field season!

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