Big Picture – Lake Scugog Research

The Big Picture:

Water lilies, one of the best plants for the lake

When you visit Lake Scugog it’s easy to be immersed with your immediate surroundings. “What’s that plant?”, “look at that blue heron!”, “the water looks so nice for a paddle right now”, or “where have all the walleye gone?”, are some of the thoughts that might cross your mind, depending on what is in front of you. Often, people get so concerned about what’s happening at their favourite spot that they fail to consider the lake as a whole. For example, a new plant may be growing at your shoreline that is considered a recreational nuisance, but is actually helping to clean the water. Similarly, walleye populations may not be what they used to be, but maybe they were never a natural part of this ecosystem to begin with. It is important that we consider ecological phenomena from the big picture, both in time and space.

The Effect of Time

When we look at a snapshot in time, we often long for those “good old days” when the walleye were so abundant in Lake Scugog rivers that you could almost walk across the water on their backs, when there appeared to be fewer plants and algal blooms, and when you could swim without getting stuck in the mud. Was this ever a reality? Maybe for a moment in time, but consider the fact that walleye were stocked in the early 20th century, and too many ‘weeds’ were a complaint then too; biological communities change naturally over time. Water quality has actually improved since the 1980’s, resulting in fewer algal blooms, probably because of the invasion of Eurasian watermilfoil in the 1960’s which used up a lot of the free phosphorus and later the invasion of zebra mussels. Agricultural practices were improved partially because of the cost of fertilizer. Indeed, our perception is often far from reality. Many anglers appreciate the complex habitat that milfoil provides for fish.

Examining a sediment core

Lets go back to the year 1834, when the first dam was put in the Scugog River at Lindsay, which flooded the lake. Previously, Lake Scugog was 6 feet lower, and looked more like swamp land than a lake. This flooding created stagnant waters, poor water quality, and a wave of deadly fevers that caused the eviction of First Nations people from Scugog Island. Soon after, the dam was torn apart and rebuilt, and water quality got better, but Lake Scugog was forever changed. Water levels are managed by the Trent Severn Waterway, but continue to fluctuate. Bottom sediments, studied through sediment cores that allow paleolimnologists to look in to the past, indicate a rich history of altered land use and fluctuating water levels. In some areas there are meters of “mud”, made up of years and years of decaying plant material, both indicators of the lakes terrestrial beginnings and nutrient-rich (thus plant-rich) nature. THIS is the underlying ecology of Lake Scugog. Changes in fish, plants, and other biological features, are dictated by this history, which continues to evolve in to this day.

The Effect of Invasive species:

Disturbance paves the way for change. Often, it means new niches are available for new plants/animals to colonize. This is where a non-native species can turn invasive. Have you ever noticed that on roadsides, new developments, and other disturbed sites, there is a different assemblage of plants than in an untouched ecosystem? Those tall grasses with fluffy heads that line the roadsides of Southern Ontario and elsewhere are a great example of an invasive species, known by it’s latin name Phragmites Australis, that has moved in to exploit an area where native plants were too disturbed to survive.

Zebra mussels on milfoil

Another example is the zebra mussel, which was unintentionally introduced in to the Great Lakes in the 1980’s and found it’s way in to Lake Scugog soon after. At first, these tiny, undesirable mussel couldn’t be ignored; clogging water intake pipes and cutting the feet of swimmers. They even altered the nutrient cycling and water clarity of entire lakes, by ingesting algal particles and locking up phosphorus at the lake’s bottom. But, over time, other fish and animals adapted to the zebra mussel, made use of them, and the ecosystem stabilized. For example, certain fish evolved larger mouth parts so they could eat zebra mussels, thereby keeping populations in check.

This all said, it is difficult for some species, including humans, to adapt to change, in a time scale that is practical, and it is best if we prevent the spread of invasive species to begin with. This means creating as little disturbance as possible – especially alongside waterways and other corridors – and restoring disturbed sites with native plants. Keep in mind that once a new species has invaded an area, it is very difficult to control. So control what you can control (smaller patches of invasive species), and avoid causing more disturbance by using chemicals or extreme mechanical means to remove larger patches of invasive species.

The Effect of Climate Change:

The Earth is experiencing a rise in temperature, and a slew of irregular weather patterns and events that are tied to this instability. Scientists agree the main cause of the current global warming trend is the human-driven increase in greenhouse gases. Over the last century, the burning of fossil fuels, in particular, have greatly increased the concentration of atmospheric carbon dioxide.

What does this mean for Lake Scugog? It is difficult to say. Environmental scientists can use models to predict the future of our climate, but the interactions between pollutants, climate, water quality, and biological systems is very complex. Climate change is a global issue that requires global solutions. That’s not to say you can’t do your part. Decrease your amount of fertilizer use, fossil fuel combustion and biomass burning, which releases nitrous oxide, another greenhouse gas. Lobby for the importance of forests – which filter the air by sequestering carbon dioxide and producing oxygen. Leave wetlands intact – as disturbing wetlands can result in the release of large amounts of methane, a potent greenhouse gas. Similarly, practice “no till” gardening/agriculture, as tilling also releases methane from the Earth.

Change that is caused by humans, should be monitored, studied, and addressed. In most cases, change is considered undesirable, because it can be unpredictable, and something we are not prepared for. But if you think about the billions of years this planet has evolved, you will understand that some types of change are natural, and given time, the ecosystem will adapt to a new normal.

The Effect of Space and How we use it

Scugog watershed

A watershed is an area in which all water that lands on it’s surface flows to the same collection basin, eg. a lake or a river. Consider a map of Lake Scugog. The watershed for Lake Scugog is 141 km2 and of that, just under half is the lake itself.

Kawartha watershed

Now zoom out, until you can see the whole of the Kawartha Lakes watershed. The Kawartha Lakes watershed, that encompasses Lake Scugog, stretches from south of Port Perry, to North of Coboconk, East to Balsam Lake, and West to Pigeon Lake. Land uses in this area are mainly agricultural, urban and rural development, and natural areas. Every chemical, including fertilizers applied to the land, has the potential to make it in to one of these water bodies.

Zoom out again, until you can see the whole Kawartha Lakes region. You’ll see Bald, Buckhorn, Chemong, Lovesick, Stoney, and Rice Lakes added to the picture. These lakes make up a significant portion of the Trent Severn Waterway – a connected series of lakes and rivers stretching from Trenton on Lake Ontario to Port Severn on Georgian Bay. A highway, if you will, for water movement and the things that water contains. With Scugog as one of the feeder lakes (higher in elevation, so water flows out of it and in to the rest of the system), consider what impact the things that happen in – and around – Lake Scugog could have on the rest of the Kawartha Lakes system. Water chemistry? Fish species? Plants? Algae? Bacteria? You bet. All of these things can move freely, but especially with the flow of water, through the Trent Severn Waterway. This is especially important when looking at the movement of invasive species, like Starry Stonewort.

Trent-Severn Waterway connections

Take a big step back now, and look at all of North America. Consider the movement of Asian Carp up the Mississippi, which might ultimately make it in to the Great Lakes, which feed in to the Trent Severn Waterway. Think about land use in the greater picture, including the long range transport of air pollutants, which can come from as far away as China. Consider all the values of our lakes economically, recreationally, culturally, and environmentally. Now you might understand that to make a difference in that one place in time, you also need to consider what is happening up stream and down stream, and realize that the landscape, and even the entire planet is the overall driver as to what is happening