Leech Lake, Muskoka

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Monday, August 27, 2012

Loon Death Update

On the original post about the loon death I had not been able to contact the Jacobs family that discovered the dead loon. This afternoon we had a discussion about their tragic discovery.

The Jacobs family found the loon amongst some rocks adjacent to their cottage. The loon was dead when they discovered it. It had a fishing lure lodged in its mouth with a long piece of fishing line attached to the lure.

On the weekend of the discovery the Jacobs were unable to contact the Department of Natural Resources. They have since advised DNR and the loon is buried in the Hunt Camp property across the road.

We can speculate about what actually happened to our loon. It could have come across a lure that had been abandoned in the lake for whatever reason. It could have attacked the lure of a person fishing on the lake and the sheer weight of the bird and a fight that would ensue could have broken the line. The chances that it attacked a fish that had a lure in it seems remote as the lure was lodged in the loon's mouth and throat area.

Whatever happened the bird would no doubt be in shock and of course would be unable to feed. It would not have been a peaceful death.
In the last three years we have lost three adult loons and all had fishing lures in them. Our lake is so small that it seems that fishing and loons cannot co-exist without serious mishaps.

Its sad state that in instances wherever modern day humans chose to exist nature suffers.

Otter Experiences

I was out kayaking early on Saturday morning. I was exploring the rock island close to our cottage. I rounded one end of the rock outcropping and ran into two otters diving. I was within 10-15 yards of these animals. I remained motionless and they did not seem to notice me. As they came closer I moved and they dove and then resurfaced to look at me and then dove again. They continued to dive frolic just off shore.

On Sunday I was again out early for a paddle. As I was returning I noticed, from a distance, the otters in front of our neighbours cottage. As passed by I saw one of the otters on a rock along the shore eating a small fish. I returned to our cottage and beached my kayak. The otters were now in front of our cottage diving for fish I assumed. I watch for a short while and then the otters did not resurface. I went a little closer to our floating dock and I could hear something. The otters were under our dock! I went on the dock. You could hear them breathing and snorting. As well they occasionally made a type of purring sound. At the shallow end of our dock one of the otters was eating a fish. I could hear the bones cracking as the fish was being consumed.

Eventually I rocked the dock but that did not seem to bother them. In retrospect I thought I should have lain prone on the dock and looked through the opening slits along the side. I could have come eyeball to eyeball with these animals. Well maybe next time. It is evident that they use our dock frequently as their droppings are left on top of the dock. They predominantly consist of fish scales.

Another Loon Death

It is with sadness that I report that we have suffered the loss of an another adult loon on the lake. The Jacobs at 1160 Lakeshore Rd S. reported that they found a dead loon adjacent to their property on August 18th. When I heard the news I had a sick feeling in my stomach!

I have not been able to connect with the Jacobs to understand the details of their discovery and will report on the event as details become available.

We were at the lake this past weekend and saw two loons, one juvenile and one adult. The adult was making those plaintive calls and knowing of their loss the calls seemed to have a mournful tone.

This is the third year in a row that we have suffered an adult loon tragedy. Something is terribly wrong. Hopefully we will be able to research this death and with a better understanding hopefully we can take some remedial action.

Thursday, August 16, 2012

LL Bug Count July 22, 2012

 This was the Benthic (bug collection) activity that took place on our lake. Below you will find a letter from Katie the technician from Muskoka District. Also attached is an explanation of the the benthic monitoring and how it can benefit our lake by keeping on top of trends so remedial action can be taken if necessary.

Kudos to Valerie McCoy and family. They organized and provided their cottage, food, beverages etc.

We hope this is education.  

Hello Valerie,
  I wanted to thank you, your family and the wonderful people of Leech Lake for volunteering on the benthic sampling day. Everyone appeared to have a great time and learn plenty of new things. Leech Lake is very lucky to have you all.
  Please find attached an official thank you letter, followed by some graphic displays of the results. I have also included the table of all results from site 2 and the “ Benthic Macro-invertebrate Monitoring” document which helps to further explain the results.
  I have also attached a feedback form. So if you have any more suggestions for next year or the program in general, please let me know.
 Please contact me if you have any questions or concerns.
  Thank you again,
Katie Paroschy
Biomonitoring Technician 2012
The District Municipality of Muskoka
 Benthic Macroinvertebrate Monitoring

Monitoring bottom-dwelling aquatic invertebrate communities has been part of the District Municipality of Muskoka’s Lake System Health Biological Monitoring Program since 2003. In biological monitoring, composition of the aquatic-invertebrate community, the pattern of abundances of different species collected, indicates the health of the ecosystem.
Aquatic invertebrates, such as worms, mollusks, insects, crustaceans, and mites, are common indicators in biological-monitoring programs. These animals are sensitive indicators of the health, or condition of lakes and streams, and different species have different sensitivities to environmental changes such as pollution or habitat alteration. Aquatic invertebrates live between 1 and 3 years and are in constant contact with lake sediments. Contamination and toxicity of sediments affects those animals that are sensitive. For example, lake acidification is accompanied by both a decline in the total number of species present, and an increase in the abundance of those species able to tolerate acidity.

Reference-Condition Approach
One of the challenges of biological monitoring is that the composition of healthy invertebrate communities varies from place to place, and from time to time. We therefore have to understand natural variability to be able to make reliable conclusions about whether or not the community that we find in a given lake is normal or not. One way to determine what normal looks like is to sample reference sites. Reference sites are locations where human impacts (such as pollution, shoreline alteration, and development) are minimal and the aquatic ecosystem is considered to be in the best condition found in Muskoka.

Biological-monitoring assessments can make judgments about the condition of lakes by comparing samples from a given lake of interest (a test lake) against a set of samples from reference lakes. In short, reference lakes define what normal Muskoka invertebrate communities should look like in the absence or near-absence of human influence. Atypical sites, which are biologically different from reference sites, warrant further study to determine why their communities are unusual.
Because we need information from minimally-impacted reference sites before we can evaluate our lakes, much of the focus of our bio-monitoring program to-date has been on sampling reference sites. Since reference sites are assumed to be in excellent condition, it doesn’t make sense to report their condition; however, because their communities act as a benchmark for assessing other lakes, it is informative to understand invertebrate-community composition in reference lakes, and to watch for changes in reference lake composition over time. This report serves to characterize reference lake community structure, and gives a preliminary assessment of local test lakes.
Data analysis
Biological monitoring programs yield large data tables. You can envision such tables as columns of numbers, each column representing the counts of different species collected at a given location. It is very difficult to pick-out ecological patterns in such complex data sets, so it is common practice to simplify data tables into a manageable number of indices that represent meaningful ecological patterns. This is similar to the way stock-market performance is measured using indices like the TSX or the Dow Jones Industrial Average. The District of Muskoka uses several indices to simplify bio-assessments, as described in Table 1.
Table 1: Indices used to summarize aquatic invertebrate composition in Muskoka.
What it tells us:
Number of taxa collected:
The number of taxa is a measure of biological diversity. Richness increases with increasing habitat diversity, suitability, and water quality; therefore, the healthier a site’s community, the greater its number of taxa.
Percent of collection made-up of mayflies, dragonflies, damselflies, and caddisflies
(% EOT)
Ephemeroptera (mayflies), Odonata (dragonflies and damselflies), and Trichoptera (caddisflies) are very sensitive to pollution and habitat alteration. They should be prominent in healthy ecosystems, but their numbers will decline in response to stress imposed by human activities.
Percent of collection made-up of midges
(% Chironomidae)
Midges (true flies in the family Chironomidae) are tolerant of pollution and habitat changes so their dominance indicates water quality problems.
Percent of collected animals that are predators
(% predators)*
In a healthy ecosystem, the numbers of predators and prey are maintained within a narrow range. Extreme fluctuations in this balance signify that the ecosystem is sick.
Percent of collected animals that are adapted to feeding on coarse plant matter
(% shredders)*
Shredders are a group of plant eaters adapted to breaking down leaves, wood, and other plant matter that originates on land but gets transported into waterbodies. Such animals should be abundant if there is a good connection between a lake and its watershed. In addition to recycling nutrients, shredders are food for other animals.
Percent of collected animals that are adapted to feeding by collecting small pieces of organic matter
(% collector/gatherers)*
Collector-gatherers feed on small pieces of organic matter that arise from the processing activities of shredders (described above). Their presence indicates a good population of shredders, which provide them with food. Like shredders, these animals perform a vital role in energy cycling, and are prey for other animals.
Organic pollution score
(Hilsenhoff index value)
The Hilsenhoff index combines information about the abundances of different types of animals collected at a site with information about those animals’ sensitivities to sewage pollution, farm wastes, and other sources of nutrients like phosphorus, nitrogen, and carbon. High values of this index indicate pollution; low values indicate good water quality.
∗ In healthy ecosystems, the proportion of the aquatic-invertebrate community that is made-up of predators, shredders, collector/gatherers, and other animals is maintained within a narrow range. Marked divergences in abundances of any type of animal signifies a stressed ecosystem.
How do your local sites fare?
For a preliminary evaluation of your lake, refer to the attached Aquatic Invertebrate Data Sheet. If your sites are reference lakes, assumed to reflect the best ecosystem conditions in Muskoka, no assessment is warranted. For test locations, assessments can be made by comparing test-site index values against the averages for Muskoka reference lakes, which are provided in the shaded box at bottom right.
In general,
1. Richness should be high (close to the average for Muskoka or above).
2. % EOT will decrease and % Chironomids will increase over time with water quality impairment.
3. % Predators should be less than the other types of benthos (shredders, collector/gatherers) and these percentages should remain relatively constant over time.
4. The Hilsenhoff Index value should be close to the average for Muskoka or less, as a lower value indicates healthier water.
Even though most of the lakes in Muskoka are quite similar, no two lakes are identical and there are various factors that play a role in determining the relative abundances of different types of aquatic invertebrates. Comparing your lake’s data to the rest of the lakes in Muskoka is not definite, but it can give you an idea. If there is a trend in all the types of indices and data, either above or below normal, it may indicate your lake’s overall quality.