Otty Lake Association

  • Fish and Wildlife Enhancement 2016
  • Mergansers - Derek Smith
  • Shoreline Planting - Christine Kilburn
  • Porcupine in Field - Cathy Kari
  • Nesting Box Volunteers
  • Geese Family out for a Stroll - Rick Haas
  • Wildlife Conservation
  • Wetland Identification

Otty Lake Environment

State of the Lake Reports   |   Blue Green Algae   |  Crown Island Use |   Let's Starve Phosphorus | Algae Close Up | Ticks and Lyme Disease |

Murray using secchi disc
State of the Lake Reports

2020 is the seventh consecutive year that the OLA has summarized the condition of our lake and the environmental activities completed in a report to members. The report includes sections on water quality, water levels, algae, wildlife, invasive species and other monitoring activities, and is released in the fall.  

2020 Report | 2019 Report |2018 Report | 2017 Report | 2016 Report | 2015 Report | 2014 Report

Blue Green Algae Bloom Swan Lake
Blue Green Algae

There have been no recorded incidents of blue-green algae blooms at Otty Lake. However, over 2014, there were four confirmed cases in other local lakes. As of early August 2015, blue-green algal blooms were confirmed on two local lakes.

While cyanobacteria is often present in low concentrations in Eastern Ontario water bodies, it is a complex set of conditions, including nutrient loading and climate, that causes them to multiply and blooms to form. Please don't feed the algae in Otty Lake!

If You Detect a New Blue-Green Algae Bloom:
  • Contact the MOECC (Ministry of the Environment and Climate Change) Spills Action Center at 1-800-268-6060. This is a 24 hour 7 days a week service.
  • If you are unsure it is blue-green algae, you can contact the Lake Association for assistance. Derek Smith, 267-5225 or Murray Hunt, 264-9273 from the Lake Association Environment Committee can come to the site of the algal bloom to assist you in the identification
What Happens Next:
  • The Spills Action Centre will determine if it is indeed blue-green algae and take samples to determine if it toxic. This could take two to three days. They will also notify the local health unit
  • Determining the level of toxicity could take a week or more.
  • During this period the Health Unit will advise against drinking, swimming, fishing or using the water for household use in the area of the algal bloom.
  • In addition to public announcements, the lake association would be asked by the health unit to use their contact list help ensure all affected parties are informed.
Slide Presentations
  • Presentation by Teresa Clow, Public Health Inspector, with the Leeds, Grenville & Lanark District Health Unit to the April 2015 Lake Networking Group Meeting.
  • Presentation by Laurel Rudd, Surface Water Scientist, focuses on the MOECC response to blue-green algae sitings, and was mentioned at the April Lake Networking Group meeting.
  • Presentation by Mike Yee, of the RVCA, to the Lake Networking Group meeting of September 2014, adapted from Algae Blooms in Ontario's Lakes: Analyzing the trends" by Jenny Winter, Ministry of the Environment and MOE Fact Sheets.
island mist by Hendy
Crown Island Use

Twenty islands on Otty Lake are "Crown Owned" by the provincial government and managed by Ontario's Ministry of Natural Resources (MNR).  MNR promotes a free use policy of Crown Lands and focuses on positive messaging, emphasizing good stewardship. If you are going to be using any of these islands, read these suggestions for responsible use.   


Otty lake green algae
Let’s Starve Otty of Phosphorus
Algae at Otty Lake

In the last several years there has been an increased amount of blooms of green algae at Otty Lake. Periodic sampling of these algae shows that they are a green filamentous type predominately of the two species, Spirogyra and Mougeotia. These green algae are not harmful to humans. It is unclear why there has been a noticeable increase in profuse algal blooms at Otty and other local lakes in recent years and steps are being undertaken by the responsible government authorities to initiate research into this matter. However, there is meaningful action that Otty Lake cottagers and residents can take to control algal blooms.

Algae Close Up

August 10, 2014 - Reports Derek Smith: "The Spirogyra have just started to bloom in shallow bays around Otty this week. The bloom in early June was a different species. Notice the spiral chloroplasts which  make this one easy to identify.

Here are three microscope pictures; the black point in the second are algal “zygotes”, and they are shown in greater detail in the third.

This species has a certain beauty under a microscope, but is not so pleasant as a floating mat."

Spirogyra algae View 1 Spirogyra algae view 2 Spirogyra algae view3

Below is an example of Cladophora, a branching filamentous green algae.

Cladophora on Rock Cladophora closeup

tickTicks and Lyme Disease

Populations of Lyme disease-infected black-legged ticks have been found in the Otty Lake area. Not all blacklegged ticks are carriers, but the risk of contracting Lyme disease is on the rise in Canada. Your risk of a tick bite is greatest in spring and summer in forested and overgrown areas. There have been reported cases of Lyme disease in humans in Lanark, Leeds and Grenville, as well as in dogs. Protect yourselves and your pets. If you develop symptoms, consult your healthcare provider right away. A firm diagnosis of Lyme disease can be difficult, but the disease can be treated with 2-4 weeks of antibiotics. A vaccine is available for protecting dogs against the disease. Note that as of July 1, 2014, the Health Unit does not accept ticks for analysis.

Tick Smart Poster >>
Ministry of Health and Long Term Care >>
LLG Health Unit Information >>
Ticks, People and Pets >>
Lyme Disease: Why You Should Take Note>>