Study results: 1,570 potential derelict traps off the NH Seacoast

1,570 Potential Derelict Lobster Traps located during 4 days of Derelict Fishing Gear Sidescan Sonar Survey: Portsmouth, NH and the Isle of Shoals

Rozalia Project for a Clean Ocean conducted a 4 day sidescan sonar survey to locate derelict fishing gear around the coastal waters of Portsmouth, NH and the Isle of Shoals on the behalf of the Blue Ocean Society for Marine Conservation, NH Sea Grant and UNH Cooperative. The Sonar survey was conducted as part of the Marine Debris to Energy Project, a NOAA funded project to detect and remove marine debris along the coastline from southern Maine to northern Massachusetts. The Sonar survey was also supported by Optima Bank, Portsmouth, NH and the Kittery Point Yacht Yard, Kittery, ME.

METHOD:

The survey was conducted from Rozalia Project's 60ft sailing research vessel American Promise utilizing a Tritech Starfish sidescan sonar towed from the starboard quarter of the vessel at speeds ranging from 1.9-4.3 knots, in depths of water from 20-135 feet.

The aim of the survey was to locate derelict fishing gear and investigate it's volume and geographical distribution, in this case predominantly derelict lobster traps (pots)

Potential derelict lobster traps were identified on the sonar image by the following criteria: red dots=potential derelict trap, blue dots=active trap. The following examples are from the sonar survey:

1:    Groups of 3 or more lobster traps clumped together in close proximity:

2: Trap line of 3 or more with v shape or large deformation of the multi-trap line:

3: Individual traps with no active gear nearby:

4: Trap lines with no active lobster buoys within the Starfish’s range:

When potential derelict lobster traps where viewed on the sonar display, a snapshot was taken from the sonar image. In addition, waypoint locations and track information were recorded on an iPad utilizing Navionics charting software with snapshot time, waypoint number, track number, track start and finish GPS positions and track start and finish times recorded on data sheets.

RESULTS

1: Portsmouth Harbor/Piscataqua River Entrance (Fort Constituition to Gunboat Shoal): 

• 30.18 potential derelict traps per mile
• 9 tracks totaling 11.1nm were surveyed with 335 potential derelict lobster traps located

2: Gunboat Shoal to Rye Ledge:

• 102.86 potential derelict traps per mile
• 9 tracks totaling 10.14nm were surveyed with 1043 potential derelict lobster traps located

3: Isle of Shoals:

• 25.95 potential derelict traps per mile
• 7 tracks totaling 7.4nm were surveyed with 192 potential derelict lobster traps located

Survey totals:

• 1,570 potential derelict lobster traps located
• 28.64 miles of ocean were surveyed
• 296 waypoint locations of potential derelict traps recorded on sonar

CONCLUSION

1. Clumps/groups of lobster traps are often located at substantial terrain changes, for example, from sand to rock ledge (see below – ledge off Rye Harbor):

2. A higher volume of potential derelict lobster traps exists within 1.0 mile of the coast.  Density of inshore tracks  = 72.8 pdlt/mile
3. A higher volume of potential derelict lobster traps exists in proximity of highest density of active fishing gear (recommend ROV survey to confirm accuracy of sonar survey in these high density active trap areas).
4. A lower volume of potential derelict lobster traps exists offshore beyond 1.0 mile of the coast. Density of offshore tracks = 37.7 pdlt/mile.
5. A lower volume of potential derelict lobster traps exists in areas of lowest density of active gear (Isle of Shoals, and offshore tracks).
6. Derelict lobster traps are not static, during the survey, American Promise re-surveyed a shipwreck that was part of a 2008 Sonar Survey (below). During the 2008 survey the top of the wreck was covered by over 20 derelict traps. During our 2011 survey, the sonar image shows a wreck with no derelict lobster traps on it, just an active trap line to its port side. More research is needed on what moves the traps around (storms, draggers?) and where they go.

In the opinion of the Rozalia Project, the waters of coastal New Hampshire and the Isle of Shoals have a significant amount of derelict fishing gear on the sea floor with several inshore (within 1 mile of coast) locations where it has accumulated that would make removal of the derelict fishing gear feasible.

Technology Starfish style and a beautiful place

After a week in the mountains (awesome) of not necessarily rest but a different kind of work (OK, yes a little rest) we are back in action on American Promise. The Blue Ocean Society (who are dedicated to marine conservation and do a huge amount of work in everything from marine mammal conservation to beach clean ups to awareness campaigns - getting people to clean up after their dogs...) brought us in to do some survey work as part of a NOAA Marine Debris to Energy Grant. The goal this week is to look for and identify derelict fishing gear off the NH coast.

This is exciting because it marks the shift in focus for us from the trash pickup/education part of the summer to trash pick up/research part. We are getting to get a little farther from the docks and putting the equipment through some different challenges. Yesterday was

all about the Starfish side scan sonar. Tritech is the company who makes the Starfish and who generously donated this unit for the season. This is a small, towed sonar that looks down and to the side. It 'sees' objects by giving us both bright returns and showing shadows (see photo right). The equipment is incredibly easy to set up and get running and the challenge is to learn to read the images. We are getting better and look forward to today when we do more with the Starfish and hopefully put the VideoRay down for some confirmation video.

This week is also cool because we have interns from the Blue Ocean Society aboard helping us. Yesterday's crew: Abby, Mike and Ben were great each contributing their expertise and experience from getting the GPS that goes with the Starfish to work to giving us lots of excellent info on the local marine mammals (they are in the photo at the bottom getting ready to set off for the day). We're looking forward to having them back and meeting more for the next few days.

As high tech as the Starfish and ROV, we found the iPad to be an amazing tool for our work yesterday. We used the Navionics chart plotting app to show our transects and then put in waypoints of areas of interest. Then, we were able to bring that info over to Google Earth and get some quick visual info. Even our interns (classically trained in handheld GPS units and GIS software) were impressed!

Lastly, but by no means least, I have to say how beautiful a spot we are in. James found the Kittery Point Yacht Yard by looking for a place to moor for the week that was protected and on the seaward side of the bridge that leads to Portsmouth proper (where the headquarters of Blue Ocean Society is located). It is beautiful and even better, the guys who run this yard are friendly, helpful, know their stuff boat-wise and are interested in what we are doing. They are psyched to be the hosts of the Trash Bash tomorrow and have allowed us to be on the dock rather than the mooring (yipppee).

Speaking of support, this week is also made possible with the help of Optima Bank. They helped us get American Promise in the first place and are enthusiastically supporting what we are doing with her. We even get Carol from Optima onboard to help with the survey work tomorrow.

So, as I head off for day 2 of the survey, I want to say thank you to Tritech, Blue Ocean Society, KPYY and Optima Bank and to invite you all to the Trash Bash tomorrow (Thursday August 4) from 5-7 at the Kittery Point Yacht Yard. Thanks to Boat US Foundation, we will have drinks, food and goodies to give away and the event is free and open to the public.

Watch the coming storms.

rzm

ps. I could have done an entire post on this... but on the way here from Boston we say 7 Minke whales, a seal and a jumping tuna! See the Rozalia Project facebook page for photos from that day.

Spotters and Netters

We are now sailing east away from our first stop of Trash Tour 2011 in Oyster Bay and toward Narraganset Bay where we will visit 4 locations for marine debris programs and trash pick up. I just relocated from the very hot cabin/nav station to the deck and am loving the invention of laptops with decent batteries (it is a hot, sunny day with around 5 knots of breeze). **After writing this, we lost connectivity, so I am now posting after a lovely afternoon of up to 9 knots of speed and much cooler temps. Wind died again as we are approaching dusk and we are going to sail through the night to Newport to get ahead of

some storms forecast for tomorrow afternoon (and sail through the race with a favorable tide).

Thanks to the efforts of the Waterfront Center, Oyster Bay Marine Center and Oak Cliff Sailing Center, it was a great first stop. We had around 136 people participate in the dockside programs and we ran our very first on board program with WFC’s high school sailors.

Thursday morning, we welcomed 4 high school sailors and their 2 instructors/naturalists on board American Promise. After a history of the boat (and tour) as well as an intro to the types and problems of marine debris we designated some sailors as spotters and others as

netters. Before I give you the results, I have to say that we had not seen really any trash during the 2 days of boat work that we had before starting the program. There is a lot of current flushing in and out of the Bay, much of the shore is privately owned (rather than open for picnicking) and the oyster dragging process must get a lot of the trash off the bottom. That said, the kids did a great job spotting and picking up a box full of trash (we are about to weigh and measure it during today’s passage) all in a mere 30 minutes. On the way back, we balanced the low tech (but effective) nets with the high tech and revved up the Tritech Starfish side scan sonar which confirmed our expectations of a flat, uniform bottom (good for the oysters).

We triumphantly motored in to the area where the WFC runs their programs (nets held high) and picked up a mooring next to their oyster dragger turned education/tour boat, Christeen. That afternoon and all day Friday was spent with lots of WFC sailors, their instructors,

and the interested general public. We were using the VideoRay ROV and nets off the dock. We were happy to find that there was not a lot of trash on the bottom near WFC’s docks but there were some critters and some beautiful marine flora. Similar to what we found on the surface, you just need to look hard enough and even what seems like a very clean area of the water will give up its marine debris and we pulled out some plastic, a particularly elusive Bud Light can and a metal water bottle.

The WFC has a very diverse, well run and busy program incorporating marine education into their sailing and paddling programs and we found their young sailors aware of their surroundings and psyched to learn more. There was genuine excitement with each piece of trash we found and recovered and we even had some sailors and locals learn to fly the ROV and help with tether handling.

Sloane did a great job with her first marine debris program and we are now lucky enough to have Vermont sailor, Laura Dunphy, with us for the next week. Laura worked with me over the winter and won a Young Explorers Club grant to join us and study tunicates in Narragansett Bay (as I write this, Laura, Sloane and Hickory are napping on deck in preparation for an overnight sail into Newport).

Before heading for my turn on the helm, I want to say another big thank you to Alicia, Dave and all the instructors and naturalists at the Waterfront Center in Oyster Bay for being our

first hosts, to Oak Cliff Sailing Center for helping to make this happen and for spreading the word (and for some advice on our engine and for taking Sloane out on a classic boat for a Thursday night race) and to the Oyster Bay Marine Center and their launch drivers for the genero

us donation of a mooring and patience as Hickory and Smudge learned to get on and off AP and left handfuls of dog hair in their lovely launches. We appreciate all of the help and genero

sity and are psyched to head into Narragansett Bay for some more boat work, fireworks and best of all, trash pick up and education programs.

Think breeze (so we can keep rolling east under sail rather than motor),

rzm

(and the Rozalia Project/American Promise crew: James, Sloane, Laura, Hickory and Smudge)