Town of Leicester & Lake Dunmore Fern Lake Association
Aquatic Invasive Species
Final Report 2015
Photo courtesy of Jim Meyersburg The Town of Leicester and the Lake Dunmore Fern Lake Association respectfully submit the 2015 Final Report for Vermont Department of Environmental Conservation Grant in Aid AQ16-11.
Table of Contents
Overview ...... 2 AIS Operations ...... 2 Looking Forward ...... 4 Lake Dunmore ...... 5 Plants Harvested From Lake Dunmore (In Bushels) ...... 6 Fern Lake ...... 6 Plants Harvested From Fern Lake (In Bushels) ...... 7 Detailed Map of Harvesting data by Month ...... 7 June 2015 ...... 8 July 2015...... 8 August 2015 ...... 9 September 2015 ...... 9 Attachment D ...... 10 Attachment D Supplemental Sheet ...... 10 2015 Shoreline Watch & Invasive Species Patrollers Volunteer Hours ...... 12 Other Invasive control Volunteer hours ...... 12 Supplemental Milfoil Control Programs ...... 13 Weevil Program ...... 13 Member Education...... 13 2015 Greeter Program ...... 13 2015 Greeter Program Reporting Data ...... 14 2015 Greeter Program Inspection Results ...... 16 Press Release ...... 17 Addendum A: LDFLA Member Communications ...... 18 Addendum B: Milfoil Training Workshop ...... 22 Addendum C: Darrin Fresh Water Report ...... 23 Addendum D: Aquatic Control Technology Contract ...... 30
2015 Aquatic Invasive Species Final Report 1
Overview
The 2015 milfoil abatement program was somewhat successful in helping slow the spread of milfoil in our lakes. We had prepared for increased growth by adding new equipment and staff, but nature taxed our resources. We barely kept up with the explosive new growth by season's end.
We had suspected this might happen at our early strategy sessions and concluded that stopping new patches from expanding was a better use of limited resources than cutting the existing forests. We therefore marked the biggest patches with buoys asking the public to avoid them.
This strategy would result in a holding pattern for the 2015 season while we applied for an herbicide permit for the 2016 season. The LDFLA board created a new AIS (Aquatic Invasive Species) committee this season with a team that provides a wide range of skill sets. This adaptation was greatly appreciated and will enhance the efforts in the long-term.
AIS Operations
We built a fourth harvester based on a decision made last fall. Construction started in February and was completed by mid May. We also completed spring maintenance at this time, and all four harvesters were ready by May 20. The boats received new roofs and fresh paint along with needed repairs.
We decided to implement a marine radio two-way communication system for all four harvesters plus the support Lund skiff. This significantly improved efficiency.
We began crew hiring in mid April. Operations Manager Troy Carr interviewed 28 prospective workers, of which 14 were hired. We lost 3 during the training period. We then hired 3 more. Training started June 1st for the new crewmembers, but seasoned crew manned 2 boats immediately to begin survey work and hand harvesting. We had another staffing setback when Keewaydin Camp, who provides our dock space and base of operations, implemented a crew background check policy due to new insurance requirements. This resulted in the further loss of 2 crewmembers. Again, these positions were eventually filled.
Mechanical failures plagued the beginning of the season. One boat broke its transom, dropping the motor overboard. We had it working again within two days. Another boat overheated its motor, putting it out of commission for a week. We repositioned the orphaned extra crews to the Lund skiff to hand pull in shallow areas during these times. Most other issues during the season were resolved immediately.
Early June surveys showed surprisingly heavy growth in Bridge Bay in the north end. The East side had the expected forest, but the West side was the heaviest we had ever seen. We had to employ two harvesters for most of two weeks to cut a channel for boats in this heavily travelled area.
Fern Lake had so little early growth that it didn't warrant a full time harvester till July 13th. We kept it there until August 3rd, when it was required back on Dunmore. It returned to Fern Lake August 15th for
2015 Aquatic Invasive Species Final Report 2 an additional 8 days. We concentrated on keeping the homeowners’ docks and swimming areas clear. As part of the master isolation plan, we decided to leave the two stable forests on the lake in anticipation of treating them with herbicide in 2016. Since there is almost no motor traffic, we didn't need to buoy the areas.
The two major dense growth forests of milfoil in Lake Dunmore are on the undeveloped shoreline on the East side of Bridge Bay and an area called The Spine, which extends south from the outlet of Sucker Brook which feeds the lake from the two reservoirs upstream. Both these areas are fed nutrients from the mountain rivers. These are well-developed, stable stands. We decided to leave them, mark them, and isolate them from boat traffic to allow us to concentrate our limited resources on expansion patches.
We first cut a channel to the east of the Spine to allow homeowners access to the lake, and then concentrated on the west, which had significant growth in an area previously free.
For this reason, if you compare the raw bucket counts from the 2014 season to the 2015, you will see an actual decrease in numbers. It is much easier to plow through a dense forest and produce impressive numbers, than to harvest individual plants in a wide area. Those individual plants, though, have the propensity to develop dense growth if given the opportunity.
We used isolation techniques on two other areas; the shallows to the south of the state launch ramp, and another area outside the launching area, which we eventually were able to clean out completely.
The area north of Branbury Beach was worked and cleaned out twice during the season.
The very south end of the lake was a challenge, and we had limited success harvesting it. The bottom was too muddy and murky and shallow to allow a hand puller or a diver to completely work it. Both the extreme north and south points of the lake had similar properties, probably a catch all from the wind. We did have effective Photo courtesy of Jim Meyersburg local homeowner hand pulling.
We implemented a new pickup service for the full buckets with the implementation of a two way VHF communication system. Previously, when a harvester filled all baskets onboard, the crew had to coil the hoses, return to base, and unload before they could continue harvesting. This process took over an hour. We put the Lund skiff to work relieving the harvesters of full buckets and replacing them with fresh empties. This worked brilliantly, keeping the harvesters on station all day.
Another change to improve efficiency was the implementation of the 4 day/10 hour workweek. Since it takes up to an hour to commute to the worksite and prepare the boat for work, and another hour
2015 Aquatic Invasive Species Final Report 3 to put it away, this prep time was a significant part of an 8-hour day. The prep time stayed the same, but was a smaller percentage of a 10-hour day, so more time per day was spent harvesting. This made for more complicated crew scheduling, but was worth it.
We had good community involvement this season. In both the north and south ends, homeowners formed neighborhood kayak outings on Monday morning to pick up floating fragments, resulting from heavy weekend boating. We called them Frag Mondays, and had designated areas that they would pile the frags and a boat would retrieve them. We encouraged homeowners to police the areas around their docks, and had some success with that. One individual, Cab Hatfield (also an AIS committee member) did a significant amount of work hand picking the entire North Cove all season, relieving the crews from a good portion of that job. See the maps on pages 8/9 for further details.
We had acquired a permit to apply a benthic barrier this season. Since we had limited experience with this method, we were determined to experiment with it. We had one homeowner in Bridge Bay whose property was completely isolated by dense growth. August 1st we proceeded to lay a barrier 14' by 100' from her dock to open water. It cost $1,400, and took most of a day to install. It did provide the homeonwer some relief, but the dense growth on either side eventually bent inward and reduced the path width. On September 15th, we did a GoPro underwater survey of the barrier. It had over an inch of silt on it and many milfoil plants growing on the Aqua Screen. To be fair, it was right in the nutrient path of an inflow stream. In retrospect, it was not the best place Photo courtesy Jim Meyersburg to have tried this.
We had lost most of the crew by the end of August due to school starting, and early September saw only one crew working. The weather was unusually hot and sunny, so the milfoil exploded again. They were overwhelmed, but beavered on for two weeks.
Looking Forward
This season was a holding pattern. It was designed to hold the line until we can obtain a permit to incorporate herbicides into our mix. We spent over 30 percent more than in previous years, and with 5 crews keeping 4 fully crewed boats working 50 hours a week, we barely kept the growth at bay. We are at a point where we need to start using other methods like herbicide, as the battle is unsustainable as it stands now. We have contracted with Aquatic Control Technology for support in our efforts to pursue incorporating herbicides for future milfoil control. (See Addendum D)
2015 Aquatic Invasive Species Final Report 4
Lake Dunmore
Zone 1: By June 1st this year North Bay was heavily infested with milfoil. This area had started to become a problem in 2014 but nothing like what we saw in 2015. We spent the good majority of a month with two full time harvesters in Zone 1 - approximately two weeks of which were spent creating a channel through the dense growth, allowing boaters to pass through. The usual area along the undeveloped shoreline of the bay was buoyed off this year to allow for appropriate use of resources in hopes we would be able to treat this area with herbicide in 2016.
North Cove saw more growth than usual. The majority of this cove is taken care of by Cab Hatfield, a volunteer of the lake. He was hard at work all summer doing his usual hand harvesting but at times was overwhelmed with the new growth and our crews helped accordingly. See the maps on pages 8/9 for further details.
Zone 1 resulted in a total of 721 bushels this season.
Zone 2: The Branbury beach milfoil patch stayed around the same size as it did in 2014. There was however a new smaller bed of milfoil closer to shore which was quickly removed. We will have to keep our eyes on this area next year.
The large dense patch to the west of Branbury beach we have had in past years has become quite a bit larger. This area was hit hard early on by our suction harvester and again in early September in hopes of knocking the growth back for next year.
We are now starting to see more growth on the west shore in this zone. A small cove south of the boat ramp had significant growth which we quickly buoyed to minimize plant disturbance while we worked on the high traffic boating areas. The milfoil in the cove was removed in mid August.
Zone 2 resulted in a total of 668 bushels this season.
Zone 3: The “Spine” which is our usual battle every year on the east shore continues to grow outwards. This area was hit two different times in 2014 in hopes of slowing down this monster infestation.
With all the new growth around the lake we knew we were not going to be able to tackle this whole area as in years past. For this reason we only hit the shoreline outwards 100' to give residents a milfoil free zone.
Since the majority of the area was going to be left untouched we buoyed the spine to eliminate the thousands of fragments that were going to be created by boat traffic. This is an area we are hopeful to use herbicide treatment if permitting allows.
On the west shore, just south of the island, we had some growth in 2014, but were quite surprised to see all the new growth that was showing up come July. The milfoil growth in this part of the lake was usually two days work in previous years. This year it took the good part of a week to eliminate all the
2015 Aquatic Invasive Species Final Report 5 new growth, which was also followed up by two days work in early September.
Zone 3 resulted in a total of 1588 bushels this season.
Zone 4: When we talk about zone 4 on the lake we are always talking about work done in South Cove and a little bit of shoreline work. This year was different! We had a major problem on our hands. The center of the lake, which has never given us any problem, had exploded with milfoil growth. It wasn't anything like we had ever seen. It wasn't a bed of milfoil; it was just large plants scattered around a huge area. The sediment in the area is very silty with no bottom to stand on making it extremely hard to work for our crews. We spent a good portion of the summer working this area with new growth popping up all the time.
South Cove was hit numerous times throughout the summer by a crew of hand harvesters. The growth in this area of the lake has not changed compared to years past. Hand pulling is very slow tedious work with very limited visibility from the sediment below.
Zone 4 resulted in a total of 502 bushels this season.
Plants Harvested From Lake Dunmore (In Bushels)
Year 2011 2012 2013 2014 2015 Zone 1 390 300 175 875 721 Zone 2 50 175 425 400 668 Zone 3 677 2000 2900 4150 1588 Zone 4 17 150 100 75 502
See detailed mapping of harvest locations later in this report.
Fern Lake
Fern Lake had so little early growth that it didn't warrant a full time harvester until July 13th. We kept it there until August 3rd, when it was required back on Lake Dunmore. The shoreline was covered with its usual milfoil. This section is extremely difficult to suction with the harvester as overhanging
2015 Aquatic Invasive Species Final Report 6 branches clog the hose. For this reason, we left much of this shoreline alone.
The harvester returned to Fern Lake August 15th for an additional 8 days. We concentrated on keeping the homeowners’ docks and swimming areas clear. As part of the master isolation plan, we decided to leave the two stable forests on the lake in anticipation of treating them with herbicide in 2016.
See detailed mapping of harvest locations later in this report.
Plants Harvested From Fern Lake (In Bushels)
Year 2011 2012 2013 2014 2015 Zone 1 25 300 200 100 297 Zone 2 50 525 625 600 Zone 3 150 1000 700 615 Zone 4 75 500 275 250
The milfoil was transported and disposed of daily, by the milfoil crew, in a vacant field approximately one half mile from the Lake Dunmore boat launch.
Detailed Map of Harvesting data by Month Key: The Yellow numbers represent milfoil operations crews’ efforts.