By Kate Hill
Staff Writer
On Saturday, Nov. 16, the Cazenovia Lake Watershed Council (CLWC) presented the 2019 Lake Summit at the Village of Cazenovia Municipal Building.
CLWC was created in 2008 through an inter-municipal agreement between the Town and Village of Cazenovia to provide a forum for stakeholders to gather and discover effective, long-term approaches to protecting and restoring the environmental health and recreational quality of Cazenovia Lake and watershed.
Harmful algal blooms
Dr. Greg Boyer, chemistry professor at SUNY ESF and director for the Great Lakes Research Consortium, delivered this year’s keynote speech.
Boyer addressed the complex issue of Harmful Algal Blooms (HABs) — a topic that he has researched for nearly five decades.
He said blue-green algae (BGA) are not actually algae at all, but highly evolved types of bacteria called cyanobacteria.
According to Boyer, of the approximately 8,000 species of BGA, only about 100 are of concern to humans.
To “bloom,” BGA require six things: nitrogen, phosphorus, energy (sunlight), warm water (temperatures above 60 F), calm winds, and a seed population.
“The thing about blue green algae is that they are not a very good food, so most things don’t like to eat them . . .” Boyer said. “The reason I point that out is that there are six things that are needed, and if you disrupt any one of those, the bloom may not happen . . . You’ve got to have all six things for them to bloom, so that leads to a lot of variability.”
Boyer said while several of the factors involved in BGA blooms are beyond human control, it is possible to alter a lake’s nitrogen and phosphorus levels and, in certain situations, to artificially circulate the water to disrupt calm conditions.
“[The algae] don’t care where the nutrients come from,” Boyer said. “They don’t care if it’s coming from agricultural runoff or if it’s coming from runoff from your street through your storm sewers, or if it’s coming from runoff from fertilizing lawns . . . They are an equal opportunity consumer . . . When you start talking about nutrients, you’ve got to consider all sources of nutrients.”
According to Boyer, climate change is causing lakes to warm up earlier in the spring and remain warm later into the fall. Warmer water temperatures enable the algae to begin growing sooner and to grow for a longer period of time.
The BGA growing period in Lake Erie, for example, is increasing by about two days a year.
Boyer also said climate change is resulting in more frequent spring rain events, which wash nutrients into lakes and help create optimal conditions for BGA growth.
The speaker also discussed a genus of cyanobacteria called microcystis, which can produce toxins called microcystins.
“If you are exposed to [very] large amounts of these toxins, you actually will suffer liver failure and die,” Boyer said. “We worry about these toxins from a recreational point of view — swimming through them — and we worry about them from a drinking water point of view.”
Boyer reported that throughout New York State, 2019 was characterized by mostly low toxicity blooms and a few extremely toxic outliers.
He next discussed the data on Cazenovia Lake.
“Cazenovia Lake has a very nice, rich blue green algal flora,” Boyer said. “We see blooms all the time. There was one in 2012, 2013, 2014, 2016 and again in 2019 . . . These are really intense blooms . . . [The blue green algal flora is] not something new. My guess is that if we went back many, many years, we’d probably see it.”
Boyer said that while unsightly, most of the blooms on Cazenovia Lake have been non-toxic.
The 2019 samples, however, contained measureable amounts of toxins — levels that were high enough to be of concern in terms of recreation.
Boyer said the toxins cannot penetrate the skin and must be ingested in order to produce harmful effects.
He advised dog owners to hose off their pets following exposure to a bloom before the animals have the opportunity to lick the concentrated algae from their fur.
According to Boyer, the New York State Department of Health controls swimming beaches and the New York State Department of Environmental Conservation (DEC) controls recreational contact in the lake.
While the health department has the authority to close a swimming beach, the DEC can only issue an advisory notice.
Boyer also noted that the health department operates under the assumption that all BGA blooms are toxic. Once closed, a beach can only be reopened with proof that the bloom is non-toxic.
“There is all sorts of interagency chaos,” Boyer said.
The professor also highlighted the fact that, due to BGA’s buoyancy and reaction to light, blooms can seem to appear and disappear throughout the day.
“If you see the bloom, you probably don’t want to be swimming in it,” Boyer said. “If you don’t see the bloom, it’s probably okay to swim in it, but just remember that it is distributed throughout the water column, it hasn’t really gone away in most cases.”
Annual fish survey
Asia Rose — a student of Dr. Thad Yorks, professor of environmental biology and biology programs at Cazenovia College — discussed the 2019 “Cazenovia Lake Fish Community.”
Information was gathered on the species, abundance and relative weight or “condition” of the fish sampled.
“The relative weight is basically a BMI chart for humans,” Rose said. “It tells you what the weight of the fish should be based on the length of the fish. If [the weight] is above that it’s a good thing, because it means that there is enough food in the lake.”
According to Rose, the survey suggests that the lake is home to a relatively healthy fish population and that the bluegill, pumpkinseed and black crappie are the most common species in the lake.
Rose also reported that although the lake has been restocked with walleye every year since 2015 (apart from 2016), the efforts to increase the population have been unsuccessful.
According to Rose, the lake’s larger fish are likely consuming the small “pan-size” walleye before they can reach maturity.
European Frog-bit Removal Project
Kiernan Blouin and Breanna Kern, of Cazenovia College, provided an update on the status of Cazenovia’s ongoing European Frog-bit Removal Project.
This past fall, Cazenovia concluded the second season of the three-year, DEC-funded project aimed at eradicating the invasive species.
Throughout the summer, teams of Cazenovia College-employed crewmembers and community volunteers worked to hand-pull and discard as many of the invasive plants as possible.
European frog-bit (EFB) grows small lily pad-like leaves, about the size of quarters, and produces white flowers with three petals and yellow centers.
Relatively late in the growing season, dormant “overwintering” buds, called turions, form on the ends of the stolon.
The turions eventually break off and sink down to the bottom until the next spring, when they float up and sprout.
“What we try to do is collect the plant before it produces the turions and also before it drops them . . .” said Kern.
Once established, the plant can form very dense floating mats that impede the movement of boats, swimmers, and even large fish and diving ducks.
The dense mats also create poor growth conditions in the water column that can threaten the survival of native species.
The species was first discovered in 2014 at the north end of the lake. EFB later appeared in the northwest bay and the northern inlets, and in small quantities to the south along both sides of the lake as far down as McNitt State Park.
Since the start of the project in 2018, the crews have made considerable progress, successfully removing large quantities of the plant from the infested areas of the lake.
This summer, the crews focused their efforts on the wetlands to the north of the lake.
According to crew leaders Blouin and Kern, eradication in the swamp area is not feasible.
“It’s impossible to get [the entire plant] because it just gets so entangled in the reeds that we can’t physically get to it,” explained Kern. “ . . . We figured out pretty soon that it’s [going to be] more about controlling it and preventing it from getting into the lake.”
In order to continue after the next season, the project will require a new source of funding.
Town report
Cazenovia Town Supervisor Bill Zupan discussed the town’s efforts to fight the invasive weed Eurasian Watermilfoil and to minimize silt infiltration into the lake.
Zupan reported that 190 acres of Cazenovia Lake were treated with the chemical herbicide triclopyr — sold under the brand name Renovate — at the end of May 2019.
Following the treatment, the weed harvester ran from June 25 through Aug. 19, making 20 trips and collecting 53.5 loads.
“Basically, because we did the Renovate treatment, we did the south end mostly,” Zupan said. “Because we didn’t have a wetlands permit for the north end we couldn’t do very much in the north and that’s why it was a shortened season. Near the end, in August, they were doing both sides of the lake too — the west and east shores. The Renovate treatment worked really well and that’s why we got so few loads off the whole year.”
The town also completed drainage work on the Hoffman Road, Glenwood Drive and Preston Road ditches.
According to Zupan, check dams were installed to slow down the movement of water through the ditches.
“If you slow the water down, the silt will come in behind the check dams and we can clean it out yearly and there isn’t so much sediment going into the lake,” he explained.
This winter, the town will once again use salt, as opposed to phosphorus-rich sand, on all roads in the lake watershed in an effort to reduce weed-promoting runoff into the lake.
Zupan also reported that the town is currently working with CLA to investigate the option of treating the lake with the newly approved herbicide ProcellaCOR instead of Renovate.
“It has a lot lower rate of application, [it’s less expensive], there are a lot less restrictions on it, and they are having good results in other lakes that they used it on this year,” he said.
Switching to ProcellaCOR will require a number of steps, including the re-writing of the town’s lake management plan and environmental impact statement, the completion of a CLA-funded ovate amber snail study, and approval from the United States Fish and Wildlife Service.
“It’s basically going to be a whole year project to see if we can use this new chemical,” Zupan said.
The supervisor also said he would support a partnership between the town and Cazenovia College to continue the European-Frog-bit Removal Project once the DEC grant expires.
CLA report
Prior to delivering the CLA annual report, CLWC Chair Sam Woods presented “rake toss” study results — reported by Robert L. Johnson of Racine-Johnson Aquatic Ecologists — to demonstrate the effectiveness of Cazenovia’s Eurasian Watermilfoil management efforts.
In 2018 — a non-treatment year — 93 percent of the 300-plus sites sampled had milfoil present and 23 percent had dense concentrations of the invasive weed.
Following the 2019 treatment of the lake, milfoil was present in only 33 percent of the sites. Dense milfoil was not detected at any of the sites.
“The chemical treatment really does work quite amazingly well and the timing of the treatment is important,” Woods said. “ . . . One of the things that we all think fundamentally is that we . . . would love to not treat our lake with chemicals to knock down the milfoil, but right now that’s our best option.”
Woods also highlighted the positive impact of Renovate treatment on the lake’s native species — none of which are harmed by the chemical.
In 2018, Johnson reported 282 occurrences of watermilfoil out of 2757 total species occurrences. In 2019, following the treatment of the lake, there were 115 occurrences of watermilfoil out of 2490 total species occurrences.
Woods then provided an overview of the lake treatment costs and the results of the 2018-2019 CLA fundraising efforts.
“[The lake treatment cost] is a huge issue in terms of trying to keep our lake healthy and trying to keep the recreation avenues open,” he said. “This is not cheap, and as we do this more and more years, this is becoming a greater and greater problem.”
Woods reported the following statistics:
Total cost of 2019 Renovate treatment: $248,356
Total town expenses (Renovate, irrigation, sign maintenance, etc): $46,308
Total CLA expenses (Renovate): $202,048
Total funds raised by CLA 2018-2019: $230,000
Total donors: 366 (out of approximately 3,000 residents who received letters)
Lakefront residents: 133 donors (out of 250), $157,000
Non-lakefront residents: 211 donors, $58,000
Business: 22 donors, $15,000
New donors: 51, ~$8,000
Woods went on to discuss CLA’s efforts to detect and report potential HABs and the association’s intentions to continue the HAB program and to better inform lakefront owners about proper detection and reporting protocols.
Woods said in 2020 the association plans to investigate alternative lake treatment options; to look into expanding its fundraising efforts to include everyone in the school district; to increase business fundraising participation; to continue to improve and streamline the HAB monitoring program; to explore the potential value of initiating a water sampling program at some of the key stream inflow points on the lake; and to increasing its public education and outreach efforts.
Village report
Trustee Maureen Fellows provided an overview of the activity at the Cazenovia Lake Boat Launch based on data gathered by the village throughout the year.
The boat launch is open from the end of April through mid October.
Fellows reported that the launch usage patterns are relatively similar from year to year.
In 2019, the village issued 383 resident passes (free), 203 non-resident passes ($75 per season/$40 per half season) and 71 daily passes ($10, Tues-Thurs).
According to Fellows, the majority of people who used the launch were non-residents (62 percent).
She also noted that 56 percent of users reported fishing as their primary reason for boating on the lake.
Fellows also discussed where the non-resident users came from; the bodies of water that the boats previously launched in; the most popular launch days; the number of inspections by month; and the horsepower of the boats inspected.
All of the boat launch data will be posted on the village website at villageofcazenovia.com/parks-and-recreation following the Dec. 2 village board meeting.
Fellows highlighted the Cazenovia Police Department’s role in keeping the lake safe for residents and visitors.
She also noted that the stewards stationed at the launch hose off the exterior of the motorboats (not kayaks) as they exit the lake. The stewards also help to inform users about methods to reduce the spread of invasive species.
To view the Town of Cazenovia Lakefront Development Guidelines, visit towncazenovia.digitaltowpath.org.
To assist in the compilation of a database of lake freezing and thawing dates contact Liz Moran at [email protected].
For more information on CLA, visit cazlake.org/.
