Healthy shorelands are as valuable to people as they are vital to lake ecosystems. The area where land meets water can be both captivating and calming, and is a primary focus for many recreational activities.
Sometimes referred to as shorelines or the “ribbon of life”, shorelands are actually the wide bands of land that surround the lake, including upland areas at least 30 m beyond the riparian edge. Since shorelands are ecotones, or a meeting place of upland and lowland/aquatic ecosystems, they provide important food sources and habitat for 80-90% of freshwater species, as well as essential support for up to 70% of land-based wildlife too – from birds, to minks, and moose.
The “shoreline” is not a mere “ribbon”, but rather a 100-foot band beginning at the littoral zone (about 3 feet into the lake) and stretching far into the upland area, often comprising the majority of a residential lot. Therefore, the “shoreline” is more accurately referred to as the “shoreland”.
In their natural state, shorelands can be remarkably resilient and self-sustaining. Rocks and the deep roots of native plants along the shore help prevent erosion from wind and wave action, protecting the lake’s habitats and landowners’ properties. Shoreland vegetation also acts as a filter, guarding the lake against the runoff of harmful excess nutrients or contaminants. However, this area is sensitive to excessive use and common human activities. Careful considerations are therefore needed to balance human recreation with lake conservation.
Natural Shoreland Features and Functions
Natural shorelands have three key areas that are crucial for maintaining a healthy lake: the littoral zone, the riparian zone, and the upland zone.
- The littoral zone is the shallow water near the shore. It begins at the water’s edge and extends out to the area where sunlight no longer reaches the lake’s bottom.
- The riparian zone is the land from the water’s edge up to the area where dry land begins. It is the transition zone where terrestrial and aquatic environments meet.
- The upland zone is the higher and drier land that extends beyond the riparian area.
Although these zones have some distinct features, they are interconnected and gradually transition into each other almost seamlessly.
Maintaining the integrity and connectivity between these zones is important for lake health and the survival of the many species that contribute to and depend on a healthy lake environment.
Riparian areas occupy a small percentage of land but usually have a more diverse range of plants and animals than upland areas.
The term biodiversity is used by ecologists, biologists, and other scientists to describe the variations among all living things on Earth. It ranges from the diversity of genetic information found in individuals of the same species (i.e. genetic diversity), to the number of different species (i.e. species diversity), to the diversity of whole ecosystems (i.e. ecosystem diversity). A shoreland is said to have high biodiversity if all three types of diversity are well-distributed along the shoreland (i.e. corridors are present to connect habitats, various plants and at different heights are present, and which attract various species among different taxa), and there are healthy interactions between each of the three levels of diversity with their environment.
Shoreland biodiversity is essential to sustaining life for numerous wildlife species, supporting cultural and recreational activities for humans, and maintaining water quality.
Natural shorelands are extremely biodiverse because they feature a range of flora, fauna, and environmental conditions from two different ecosystems – the aquatic and terrestrial. This transition zone between two ecosystems, referred to as an ecotone, is marked by high habitat complexity and connectivity. Ecotones provide food, shelter, habitat, and dispersal routes for all sorts of living things. Some species may use the shoreland as their sole home whereas others are passersby that use the shoreland to hunt, travel, or simply take a water break. Native species whose ranges are restricted to the shoreland zone are referred to as endemic species and include a variety of plants such as sand-loving grasses, floodplain specialists, and aquatic vegetation, as well as invertebrates such as stoneflies, mayflies, and snails, and vertebrates such as fish, turtles, amphibians, shorebirds, and waterfowl. Animals that frequent the terrestrial area of the shoreland not only include larger scavengers such as raccoons, foxes, songbirds and bats, but also smaller, less apparent animals like beetles, dragonflies, isopods (e.g. sowbugs), and grasshoppers.
The natural fluctuation in water levels along a shoreland also contributes to habitat complexity and biodiversity. Seasonal changes in water levels and frequent wave action makes the sand and soil in these areas able to support a rich variety of plants that would not be able to grow elsewhere. For example, many shore plants require exposed, saturated soils to germinate and establish – the saturated soils at the shoreland are inhospitable for most shrubs, thus allowing more sunlight to reach the aquatic and semi-aquatic herbaceous plants instead.
Natural shorelands are also highly variable in terms of elevation. The gradient from the deeper offshore waters, moving up to the shoreland and then further upslope to the uplands offers a diverse range of conditions which support many different types of vegetation. For example, trees, shrubs and grasses grow in the upland area, whereas woody plants and emergent species (e.g. cattails and reeds) grow at the shoreline, and aquatic emergent plants (e.g. pickerelweed, water lilies, etc.) along with floating aquatic species (e.g. duckweeds) and fully submerged vascular plants (e.g. pondweeds, muskgrass) grow just beyond the high water mark in the littoral zone. This variation in vegetation along the elevation gradient also attracts a variety of different animal species.
Functions of a Natural Shoreland
Aquatic vegetation, wood debris, and rocks in the littoral zone are critical components of healthy lake habitats. Plants help supply the lake with oxygen and are important food sources for many aquatic species. Logs and rocks provide essential spawning grounds and nursery areas for fish. Combined, these features also offer places for rest and refuge for the lake’s inhabitants.
Vegetation in the riparian and upland zones form a protective barrier against the runoff of contaminants from land to water. These natural buffer zones absorb a substantial amount of excess nutrients (from leaky septic systems, the use of fertilizers, and deposits from pets, for example) before they reach the lake. Without this protective barrier, the influx of nutrients such as phosphorous into the lake (a process known as eutrophication) can cause harmful algal blooms, which lower the lake’s water quality, reduce its oxygen levels, and destroy ecosystems.
Foliage in the riparian and upland areas also keeps the land and waters cooler and intact. Tree canopy creates shaded areas that regulate the lake’s temperature (cooler lake temperatures mean more oxygen for fish and other aquatic life), and thick layers of vegetation help prevent erosion. Leaves and branches reduce the impact of rain on the shore, for instance, which is further reduced by ground cover such as leaf litter, pine needles, and fallen twigs. Below ground, the deep roots of native plants, shrubs, and trees absorb the excess moisture and their diverse roots form a complex web that acts as a “glue,” holding the shoreland together.
Natural shorelands provide food and shelter for terrestrial species as well. In fact, they are hotspots for biogeochemical activity. Compared to other habitats, the shoreland is one of the largest producers of the building blocks of ecosystems; organic carbon found here is an essential nutrient for fueling food webs. It fertilizes soil for plant growth and provides food for organisms at the base of the food chain/pyramid which then feed other species further up the ladder. Aside from providing essential energy, natural shorelands also offer safe travel corridors for wildlife. It is therefore important to preserve the features of these zones and connectivity between them to benefit life on the land and in the lake.
Shoreland alterations intended to “improve” the waterfront by removing its natural features (vegetation, rocks, wood debris) and replacing them with sand or hardened shores are harmful to landowner’s properties, the lake, and lake ecosystems. These alterations can limit or eliminate the shoreland’s potential to function as a protective barrier against erosion and contaminants, and remove important habitat and food sources for the numerous species that depend on them.
Preserving natural shorelands, restoring shorelands to their natural state, or even just incorporating native plants in a garden style along the shoreland, can benefit the lake and lake residents in a variety of ways.
For example, natural shorelands:
- Protect the lakes’ water quality
- Provide habitats for fish and wildlife
- Act as travel corridors for plants, animals, and even seeds
- Produce and process organic matter which fuels food webs
- Provide shade from the sun and relief from the wind
- Reduce noise and dust
- Dissipate wave energy, reduce erosion and help prevent flooding
- Reduce the amount of time and money spent on property maintenance
- Provide privacy and screening against social crowding
- Provide an instant learning ground and playground for children and youth
Landowners can reach their intended goals (such as preventing erosion, creating better swimming and docking areas, and improving the view) in ways that benefit people, the lake, and the lake’s inhabitants. These actions are not only easy and inexpensive, but also provide spaces where both people and the lake environment can thrive.
Shoreline erosion, more accurately referred to as shoreland erosion, is the process whereby wind, ice, water cooped with gravity all contribute to destabilizing the shoreland and displacing soil. The most common signs of erosion include:
- Exposed soil
- Rills and gullies (small channels in the soil carved by runoff downslope)
- Slumping (loose shifting of land mass downslope)
- Undercutting (when the toe of the slope has been displaced or “undercut” by waves yet the top of the slope remains)
- Scouring (erosion along the face of a bank that leaves behind exposed soil and tree roots)
- Turbidity (cloudiness in the water)
- Receding shoreland
- Exposed/slumping/leaning/fallen trees and roots
It is important to note that erosion is a natural and common process in and of itself; however, human influence has significantly exacerbated the rate of shoreland erosion over the years. Natural erosion often occurs at such a slow rate that it is barely noticeable – the natural rate of sediment accumulation in a lake due to erosion is around 1 mm/year. However, as shorelands become artificially hardened and/or where plants and their root systems are removed, the physical forces of water flows are increased, often leading to fast and noticeable effects, sometimes in unexpected areas. Some outcomes can include slope failures, which cause property damage and also threaten human life.
Typical human actions that can increase the rate of erosion around a lake include:
- Removing natural vegetation from the shoreland and water
- Hardening surfaces (e.g. installing pavement, patio stones, rip rap, concrete, etc.) that increase runoff instead of infiltration
- Creating excessive boat wakes
- Developing on land, exposing soils, trampling soil and vegetation, and
- Hydrologically altering/hardening the shoreland (e.g. installing a retaining wall where natural slopes, soils and vegetation used to be) which result in powerful wave backwashes.
Some consequences of erosion on the lake ecosystem and human property include:
- The loss of land and the creation of unsafe and unsightly areas
- The loss of wildlife habitat including siltation of fish nurseries (covers fish spawning grounds)
- Creation of sand bars on neighbouring properties which may require dock extensions
- The alteration of the lake substrate (more silt and sand sedimentation)
- Reduced water clarity due to turbidity and subsequent death of aquatic life
- Increased water temperature from water running overland on hot surfaces and into the lake, as well as removing natural shade sources
- Decreased water quality due to increased presence of heavy metals, chemicals and nutrients (phosphorus and nitrogen) in runoff (which increases algal blooms)
- Increased stress on fish and wildlife due to habitat loss and degradation
Fortunately, there are many measures that can be taken to prevent erosion from happening in the first place:
- Most importantly, if you already have a natural shoreland then you are lucky! Leaving the natural shoreland intact as much as possible is beneficial and easy to do. An untouched shoreland consisting of rocks, boulders, logs, and both dead and alive vegetation serves to hold the soil together and provide food and habitat for wildlife.
- You can mitigate runoff by reducing hard surfaces (e.g. manicured lawns, pavement, stairs, patios, decks, etc.), and instead choosing permeable solutions such as raised staircases, interlocking brick driveways, and woodchip pathways. You can even create settling pools that allow water to drain into the soil, instead of flowing over the land and into the lake, and/or connected natural plant corridors that intercept overland flows. A great investment is a rain barrel which can be used to capture runoff from your roof, and in turn be used to water your garden with!
- An easy win is to avoid constructing paths that run perpendicular to the slope and instead make paths that meander parallel or on an angle to the slope to keep water from gaining energy as it flows towards the lake – this will help slow runoff and erosion. A bonus to this solution is that meandering paths surrounded by natural vegetation also help to deter geese from your property!
- Another choice to help reduce erosion and subsequent habitat disruption in riparian and littoral areas is to watch your wake when boating! Limiting your speed to 10 km/h within 30 m of the shore is recommended to reduce wave action created from boats.
- Be mindful of erosion and siltation during construction by having contractors use the proper precautions (i.e. silt fences, hay bales, filter cloth) and avoid working when soils are loose and wet.
Gently sloping soft shorelands, particularly those covered in a diverse range of native plants, are more effective in shoreland stability and erosion control than artificial, hardened shorelands. Replacing native vegetation with wall-like structures (even small walls) is a costly, temporary, and unnecessary “fix” when it comes to protecting shoreland properties. The force of backwash from breaking waves against hardened surfaces leads to the resuspension of sediments in water and may direct wave energy, and therefore erosion, to neighbouring lands, harming adjacent habitats and biochemistry. Contrastingly, gently sloped, natural shorelands with established root systems actually dissipate wave energy remarkably effectively. In other words, artificial or hardened shorelands have little benefit to the landowner, the lake, or the lake community. Natural or softened shorelands, on the other hand, are inexpensive and nearly maintenance-free, saving the landowner money and valuable time that could be spent enjoying what a healthy lake has to offer.
Some natural and lake-friendly options for stabilizing a shoreland can include the following:
- Vegetation 🡪 Plant a variety of aquatic and terrestrial plant species, including trees, shrubs, flowers, grasses and sedges throughout the littoral, riparian and upland areas. If needed, use biodegradable erosion control fabric, such as coir matting made from coconut husks or mulch, to stabilize the soil until the plants establish roots. Some plants have extensive roots systems. See our plant list for more suggestions.
- Loose rock 🡪 Some rocks can be placed along a slope that is suffering from erosion, but rocks should be placed far enough apart to insert native plantings in the gaps. Willow stakings and other quick-to-establish and densely-rooted plants are ideal for these areas that may be frequented with water from wave action.
- Bioengineering 🡪 Bundles of branches or root wads can be inserted into steeper banks to mitigate erosion, ideally in combination with planting native vegetation. However, more severe erosion sites will require a professional to assess the extent and severity of erosion, and to determine if more complex bioengineering techniques are needed.
Play and Preservation
Some common alterations made to natural shorelands to improve recreational areas can have devastating impacts on the lake environment. Compromises can be made, however, to balance outdoor recreation with shoreland preservation.
On the Land
Lawns consisting of short, shallow-rooted grass can create open spaces for outdoor activities and easier access to the water, but they lack the absorbency needed to protect the lake from runoff. Mowing the lawn to the shore also increases the risk of erosion and flooding, and destroys habitats. Open areas with fertilized lawn also attract geese! Geese are tundra species that require open and wide sight lines to thrive. Their guano contains a bacteria that can be harmful to humans, and high nitrates that can reduce oxygen availability in lakes.
Landowners can enjoy open spaces while protecting the lake by establishing a “no mow zone” along the shore. Preserving taller, native vegetation helps maintain the lake’s natural protective barrier, or buffer zone. A minimum of 30 feet is recommended for adequate filtration and habitat preservation (100 feet is better). In general, steeper shores or shores with finer soil particles typically require larger buffer zones for optimal functioning.
At the Shore
Sand that is imported for sunbathing and wading areas is a temporary addition to the shoreland that can have long-term negative impacts on the lake environment. Sand along the shore ends up in the lake, causing siltation. When siltation occurs, the fine particles in the water can smother and suffocate fish eggs, bury mayflies in their burrows, and cover cracks, crevices, and vegetation that fish, frogs, and toads depend on to lay their eggs. To enjoy the sand and protect the lake, setting a beach back from the shoreland (especially one that is more like a sandbox and in the upland zone) can be a good compromise. Forgoing the sand altogether is even better. Maintaining the shoreland’s vegetative buffer also helps prevent soil from land erosion having the same effect on the littoral zone as sand.
When it comes to “tidying-up” the shoreland area, removing too much “wrack” (i.e. the narrow band of washed-up coarse woody debris, vegetation and dead organisms along a shoreland) can greatly reduce the biodiversity of aquatic and terrestrial habitats. Wrack is essential for providing food and organic carbon needed to support soils and sediment, and for feeding and sheltering microbes, invertebrates which support fish nurseries and other animals.
In the Water
Fewer rocks, vegetation, and wood debris in the water can improve swimming and docking areas for people, but can be disastrous for the lakes’ inhabitants. Removing these natural features means removing essential oxygen sources, food resources, and habitats for many aquatic species. Clearing an area for swimming and boating safety while maintaining areas for aquatic vegetation and other features can be a good compromise. Simply adding a buoy, flag, or other indicator of these elements is even better because it can help swimmers and boaters navigate through the waters while keeping these areas intact. For fewer aquatic plants, preventative measures are best. Limiting the amount of excess nutrients that enter the lake by monitoring what goes on the land (e.g., reducing or avoiding the use of fertilizers) and maintaining the shoreland’s natural buffer zone can help ensure there is a healthy balance of aquatic vegetation – enough for a healthy lake, but not too much to pester people or pollute the lake environment.
Docks can also be used as a bridge to bypass aquatic vegetation in shallow waters. Floating and cantilever docks have the least impact on wildlife. To learn more about building or repairing docks that minimize harm, see the Dock Primer: A Cottager’s Guide to Waterfront Friendly Docks, produced by Fisheries and Oceans Canada and Cottage Life.
Lake Views and Landscaping
The view of the lake can be improved while maintaining the natural shoreland. Pruning trees (instead of removing them) enhances sight lines while protecting and maintaining important habitat for birds, fish, and other wildlife. Trees also benefit the landowner by guarding against erosion and providing shade, privacy, and shelter from wind, dust, and noise. To learn how to properly and safely prune your shoreland trees, refer to Watershed Canada’s Maintaining Your Natural Shoreline: Native Plant Care Guide.
Don’t like the look of the vegetation along the shoreland? You can design your own shoreland garden with beautiful native plants to enhance your shoreland’s aesthetics while improving or maintaining a functioning and flourishing buffer zone. Having an assortment of plants that attract birds and butterflies can create a beautiful, lively property for you and your family to enjoy, and a bountiful lake environment for wildlife to thrive.
For more information on shoreland designs, attend a Design Your Own Shoreland Garden workshop.
Thinking of re-naturalizing your shoreland? The Natural Edge site visits are also available to help you with your project.
The Beginner’s Guide to Shoreline Stewardship describes simple actions at the shoreline that can protect lake health for future generations.
The Land Between’s own Design Your Own Shoreland Garden video provides background knowledge and start to finish guidelines
References and Reading Resources:
Coming soon: The Land Between’s Guide to Shoreline Naturalization
A Shoreline Owner’s Guide to Healthy Waterfronts, produced by the Federation of Ontario Cottagers’ Associations
A Shoreline Owner’s Guide to Lakeland Living, produced by the Lakeland Alliance
Kipp, C. & Callaway, S. (2003). On the Living Edge: Your Handbook for Waterfront Living, Rideau Valley Conservation Authority.
Love Your Lake: Erosion, produced by Canadian Wildlife Federation and Watersheds Canada
Ontario’s Biodiversity Strategy, 2011: Renewing Our Commitment to Protecting What Sustains Us, produced by the Ontario Biodiversity Council
Strayer, D., & Findlay, S. (2010). Ecology of freshwater shore zones. Aquatic Sciences, 72(2), 127–163. https://doi.org/10.1007/s00027-010-0128-9
The Shore Primer: A Cottager’s Guide to a Healthy Waterfront, produced by Fisheries and Oceans Canada in Association with Cottage Life
Take the Plunge: A Guide to Stewardship of Ontario’s Waters, produced by the Federation of Ontario Cottagers’ Associations