Threads of Life - Rivers & Floodplains | Carolinian Canada

Threads of Life - Rivers & Floodplains

The rivers, streams and creeks of the Carolinian Zone the Sydenham, Grand, and Thames amongst many are the foundation of our natural riches. Steeped in history, they wind past towns where 19th-century mills foundries and factories still stand and meander through forests of sycamore, walnut and hackberry. For centuries, communities depended on them for food, water, transportation and recreation.

Today, the largest river in Southwestern Ontario, the Grand, is still home to 82 fish species. Its world-class brown trout fishery has recently been restored thanks to a successful recovery program. Thirty four mussel species have been found in the Sydenham River, the only river that runs entirely in the Carolinian Life Zone. The Sydenham and Thames River harbour the first and second most diverse assemblages of mussels found at any location in Canada. Some of the healthiest remaining populations of some mussels globally are found in these rivers imparting a huge responsibility on Carolinian residents to protect those species.

Floodplains are seasonally flooded areas adjacent to rivers. They play an important role in recharging aquifers. Healthy floodplains are enchanting communities filled with a great diversity of trees and delicate wildflowers.

Protected Areas

Municipal parks are attracted to rivers and are characteristic of many Carolinian communities. Lawn and paved trails are now shifting toward more appropriate naturalized areas along shorelines that help to protect water quality.

The Canadian Heritage Rivers System was established by the federal, provincial and territorial governments in 1984 to give national recognition to the important rivers of Canada, to conserve and protect the best examples of Canada's river heritage, and to encourage the public to learn about, enjoy and appreciate Canada's rivers. In Carolinian Canada, heritage rivers include the Grand, Thames, Humber and the international Detroit River, providing a wealth of opportunities for community celebration, use and enjoyment

Conservation Areas are found on most Carolinian floodplains to manage areas for flooding, species at risk and recreation.

Rouge Park was established in 1995, in response to years of citizen support for the protection of the Rouge River Valley It provides the Greater Toronto Area with 50 of natural corridor from the Oak Ridges Moraine to Lake Ontario including 12 Environmentally Significant Areas, 2 provincial Areas of Natural and Scientific Interest (ANSI) and 2 Provincially Significant Wetlands. The Rouge Park Alliance, the partnership body that governs Rouge Park, will permanently protect this land as a natural environment park.

What’s the Problem?

Rivers and streams, while appearing healthy on the surface, are in fact the most degraded and polluted of all our habitats. Run-off from cities, residential areas and agricultural lands carries excess nutrients, sediment, heavy metals, pesticides, and great surges of water after storm events. Floodplains are very prone to invasion from alien species carried in water and because silt deposits during flooding renders the soil very fertile.

Of all aquatic species, North American mussels are the most threatened. Some mussels may already be extinct or soon will be. Many have disappeared from large portions of their range and the status of most others is sketchy at best. Mussels are dependent on water quality and stream features such as riffles. They are doubly affected by poor river conditions, because they are entirely dependent on a fish or mudpuppy for the larval stage of their life cycle. Some mussels are hosted by only one species of fish and many fish are also declining. For example, if the Eastern Sand Darter disappears so will its associated mussel, the Round Hickorynut. For some species, research by the University of Guelph is on-going to determine which fish are used as hosts.


Recovery Strategies

Plants Small-flowered Lipocarpha Toothcup Wildlife National Mussels Wavy-Rayed Lampmussel Channel Darter Redside Dace Lake Erie Water Snake Queen Snake Eastern Spiny SoftshellEcosystems Ausable River Grand River Sydenham River Thames River Carolinian watercourses that drain into Detroit River, St. Clair River and western Lake Erie. 

Habitat Saving Ideas

Play Safe! Carolinian Canada’s rivers and streams are wonderful places for a refreshing swim, canoe ride or recreational fishing. As fish stocks are in decline, observe the guidelines for allowable size and number of fish of each species. Be respectful of all river species, including snakes that are sometimes persecuted to the brink of extinction.

Mow Safe! Riverfront is prime real estate. Improve your environmental value by naturalizing shorelines, eliminating chemicals in areas adjacent to water and maintaining septic systems. The Organic Landscape Alliance provides information and links for healthy backyards

Buffers for All! Most riverside landowners are familiar with hazard and flood line guidelines that protect property along watercourses. Rivers with gabions, steel walls and other bank stabilization measures prevent turtles such as the Eastern Spiny Softshell from basking which is crucial to egg production and nesting. Go natural on buffers that are now required along most watercourses to protect our water quality and soils. Consult your conservation authority or stewardship council about local programs and assistance.

Farm Safe! Ontario’s Best Management Practice booklet series is a standard for landowners, based on information from a wide variety of agriculture partners. It provides a practical, affordable approach to conserving a farm's soil and water resources without sacrificing productivity. Factsheets from many agriculture groups are updated continually to highlight the latest techniques. Link to a great variety of resources from the Ontario Ministry of Agriculture and Food and the Ontario Soil and Crop Improvement Association

Clean your hulls! Our lakes and rivers are full of an extraordinary number of aliens including smelt, alewives and Pacific salmon that bring devastating impacts to complex aquatic ecosystems. The Thames River is now under invasion by Zebra mussels causing the disappearance of rare native mussels. Aggressive alien bait crayfish are impacting native populations. Ontario Federation of Anglers and Hunters (OFAH) offers an Invading Species Hotline (1-800-563-7711) for boaters, fishers and cottagers


Rivers @ Risk

Sydenham River

This river supports the greatest diversity of freshwater mussels in all of Canada. At least 34 species of mussels and 80 species of fish have been found there. Species at Risk include five mussels, eight fishes, and one turtle. Some, such as the Rayed Bean, are found nowhere else in Canada and remain at only a few locations across North America. The Sydenham River watershed is of global significance to the conservation of these species.

Where? Has two main branches (North Sydenham and East Sydenham) that drain into Lake St. Clair

What’s the problem? With extensive drainage, most of the wetlands and their natural filtering functions have been lost. The river is nutrient-rich, polluted and turbid. These widespread and chronic problems likely have been causing species decline over some time.

How to Help! The Sydenham River Stewardship Initiative was established in 2000 through the local stewardship councils (Lambton, Kent, Middlesex) and the St. Clair Region Conservation Authority to provide landowners with financial and technical support to assist them with habitat improvement projects.


Thames River

The Thames watershed is home to many Species at Risk including 7 mussels, 10 fish and 6 reptiles. The 3 branches of the Thames River drain 5,285 sq. km., the second largest watershed in southwestern Ontario. It contains one of the most diverse communities of freshwater fish and mussels in Canada thanks to fluctuating water levels, pools and riffles, high nutrient levels, long growing season and a mix of cold and warm water streams.

Where? The Thames originates northeast of London and flows 273 km through the agricultural heartland of southwestern Ontario to Lake St. Clair.

What’s the Problem? This river flows through highly developed portions of southern Ontario and, as such, faces many pressures from urban and rural land uses such as sedimentation and siltation, nutrient loading, toxic pollution, altered water flow, disturbance, barriers to fish movement, exotic and invasive species and thermal pollution.

How to Help! The Upper and Lower Thames River Conservation Authorities are working with communities and landowners to raise awareness and make changes to improve water quality, that will bring benefits to both wildlife and human communities.


Species @ Risk

Green Dragon Arisaema dracontium

G5S3. Special Concern in Canada

This wildflower grows 15 to 90 cm high with tightly packed flowers which turn into bright reddish-orange berries. It grows in damp, deciduous floodplains.

Where? In Canada, southern Ontario and southwestern Quebec

How Many? Over 50,000 plants in over 50 localities, but only about 300 fruiting individuals

What’s the problem? Destruction or modification of habitat for residential, industrial and recreational development; collection of plants for the nursery trade; low fertility and limited genetic variability

How to Help! Protect floodplain habitat from site alteration.


Blue Ash Fraxinus quadrangulata

G5S3. Special Concern in Canada, Vulnerable in Ontario

This tree grows up to 20 meters high and is named for the dye which can be extracted by mashing and cooking the inner trunk bark. Its scientific name refers to the distinctive four-angled twigs. It grows in rich floodplain forests, shallow soils over limestone or sometimes on sand.

Where? In Canada, only in southwestern Ontario.

How Many? About 40 sites with a few dozen to a few hundred trees and saplings in each

What’s the problem? Loss of habitat, removal of large seed-producing trees. It is now threatened by the introduced Emerald Ash Borer that may spread in southern Ontario.

How to Help! Some populations are protected in national and provincial parks. Protect floodplain forests. Re-establish natural habitats along river corridors.


Wavy-rayed Lampmussel Lampsilis fasciola

G4S1. Endangered in Canada

This mussel is readily distinguished by its yellowish-green rounded shell up to 10 cm with numerous thin wavy green rays. The host fish for the larval stage is the Smallmouth Bass. Adults are found in gravel riffles. Clear water may be a requirement for successful reproduction.

Where? In Canada, Grand, Thames, Conestoga, Maitland Rivers

What’s the problem? Excess sediments, pesticides, fertilizers, livestock manure, pollutants and pathogens from sewage treatment plants and stormwater runoff

How to Help! Incentives and awareness to reduce run-off into rivers and streams


Rayed Bean Villosa fabalis

G1G2S1. Endangered in Canada, Globally rare

This very small mussel is elliptical in shape, and has crowded wavy green rays. Possible fish hosts are Greenside Darter, Rainbow Darter, Mottled Sculpin or Largemouth Bass. Adults are usually well buried in sand or gravel among the roots of aquatic plants.

Where? In Canada, the Sydenham River

What’s the problem? Contaminated run-off, Loss of host fish

How to Help! Reduce chemicals in surrounding landscape and reduce run-off into rivers and streams.


Mudpuppy Mussel Simpsonaias ambigua

G3S1. Endangered in Canada

This small mussel may reach a size of 5 cm. The thin oval shell is smooth, yellowish tan to dark brown, with no markings. The only host for the larval stage is the Mudpuppy, an amphibian that lives its entire life in water. Adults live in sand or silt deposits under flat rocks in areas with swift currents.

Where? In Canada, only in the Sydenham and Thames Rivers

What’s the problem? Contaminated run-off, Loss of host fish

How to Help! Reduce run-off into rivers and streams.


Snuffbox Epioblasma triquetra

G3S1. Endangered in Canada

Up to 10 cm, this mussel has a thick, smooth, yellowish green shell marked with numerous dark green rays. The fish hosts are the Logperch, Mottled Sculpin and Blackside Darter. Adults are found in riffles in small to medium-sized rivers and streams, deep below the surface.

Where? In Canada, only the Sydenham River

What’s the problem? Contaminated run-off, Loss of host fish

How to Help! Reduce run-off into rivers and streams.


Northern Riffleshell Epioblasma torulosa rangiana

G2T2S1. Endangered in Canada

A yellowish brown or green mussel. Males are oblong and females have a large expanded posterior. This species has suffered a 95% reduction in range in North America. It needs highly oxygenated riffle in medium to large rivers with rock, fine gravel or sandy bottoms.

Where? In Canada, only the Sydenham River

How Many? As much as a 90% decline in Ontario in the last 30 years

What’s the problem? High silt loads, low oxygen concentrations, runoff of pesticides and fertilizers, loss of stream side buffers

How to Help! Reduce run-off into rivers and streams. Naturalize waterways.


Black Redhorse Moxostoma duquesnei

G5S2. Threatened in Canada and Ontario

One of the smallest suckers, this fish may grow up to 33 cm. The back is grey or olive brown and the sides are bluish silver. It is a bottom-feeder, sucking up aquatic invertebrates. It lives in medium-sized rivers with sand, gravel and bedrock bottoms with minimal siltation.

Where? In Canada, Catfish Creek, Grand, Thames and Maitland watersheds. Breeding populations are known only from the Grand and Thames Rivers.

How Many? Unknown

What’s the problem? Appears to decline after damming of a stream or river.

How to Help! Reduce siltation of rivers with appropriate buffer strips.


Eastern Sand Darter Ammocrypta pellucida

G3S2. Threatened in Canada, Rare in Ontario

This small, translucent fish with 10 to 14 dark spots along each side hides in the sand with only its eyes exposed ready to “dart” out to catch prey. It is host to the endangered Round Hickorynut Mussel. It lives in rivers, streams and lakes with sandy bottoms.

Where? In Canada, Lakes Erie and St. Clair and their tributaries and southern Quebec

What’s the problem? Siltation of sandy areas in streams and rivers

How to Help! Reduce siltation of rivers with appropriate buffering.


Bigmouth Buffalo Ictiobus cyprinellus

G5S1. Special concern in Canada, Very rare in Ontario

This large, brown sucker was first discovered in the Sydenham River in 1997. It prefers warm, muddy, highly enriched and poorly oxygenated water. Bigmouth Buffalo spawns in marshy habitat along river and lakeshores.

Where? In Canada, southern Saskatchewan, Manitoba and Lake Erie, Thames and Sydenham Rivers in Ontario

What’s the problem? Lack of spawning habitat which is flooded mid to late May

How to Help! Maintain marshy habitat along rivers and lakeshore. Protect upstream wetlands so there is enough water in May for spawning.


Northern Madtom Noturus stigmosus

G3S1S2. Endangered in Canada, Threatened in Ontario

This mottled catfish has three dark saddles on its back and grows up to 13 cm. It lives in large creeks and rivers with clear to turbid water and moderate to swift currents.

Where? In Canada, only in Lake St. Clair, Detroit and Thames Rivers

How Many? Found only twice in the Thames River in the last decade

What’s the problem? Not known


Louisiana Waterthrush Seiurus motacilla

G5S3. Special concern in Canada, Vulnerable in Ontario

This dark olive-brown bird is a warbler, not a type of thrush. It frequently bobs its tail and prefers streams in large mature, shady forests or pools of open water in swamp forests.

Where? In Canada, within a few km of the Carolinian coastline of Lakes Erie and Ontario

How Many? 150 to 300 breeding pairs

What’s the problem? Forest fragmentation, Stream pollution, siltation and development

How to Help! Keep shady forest buffers over clear water streams. Reduce stream siltation with grassy buffers.


Eastern Spiny Softshell Apalone spinifera

G5S3. Threatened in Canada and Ontario

This fascinating turtle is large and flat with a rubbery shell and snorkel-like nose. It is also known as the pancake, pig-nosed, or rubber-backed turtle. It lives in rivers and shallow, sheltered lake inlets with sand or mud bottoms.

Where? Fragmented into about five populations in Canada: Lake Champlain in Quebec, Thames River, Sydenham River, Long Point and Rondeau Bay

How Many? Less than 2500 adults

What’s the problem? Habitat loss and alteration, Collection for the pet trade and food, Pollution

How to Help! Protect open sandy shorelines and river islands for nesting.


Lake Erie Water Snake Nerodia sipedon insularum

G5T2S2. Endangered in Canada and Ontario

This harmless blotchy, dull snake can grow up to 115 cm. It spends most of its time in water along shorelines where it hunts small fish and crayfish.

Where? In Canada, Pelee Island and other nearby islands

How Many? Unknown, drastic reductions in recent years

What’s the problem? Persecution by humans, Shoreline development

How to Help! Lakeshore landowners can protect critical habitat by keeping natural rock formations, wild grasses and shoreline wilderness.


Queen Snake Regina septemvittata

G5S2. Threatened in Canada and Ontario

Also known as the crayfish snake, this slender, aquatic snake is moderate in size (38-61 cm) and marked by 7 long stripes. It lives in creeks, streams and rivers with rocky shores and bottoms.

Where? In Canada, rivers in the Carolinian life zone

How Many? Likely 100’s, known at only 16 locations since 1979

What’s the problem? River shore modifications, Pollution, Loss of crayfish and other prey

How to Help! Keep river shores natural and eliminate chemical runoff.



Carolinian Canada Coalition 2009

Content based on 2004 guide by Michelle Kanter, Dave Martin, Veronique LeHouk, and Jane Bowles

Many Thanks to Photographers who donated their work for this project:
Jane Bowles, Allen Woodliffe, John Ambrose, Scott Gillingwater, Ben Porchuk, Rob Willson, Mathis Nativik, Shawn Staton, David Mihilik, Joe Milner, George Brackx, Kevin Railsback, Hamilton Conservation Authority, Essex Region Conservation Authority, Margaret Pickles, Leora Berman, Donald Kirk, Upper Thames River Conservation Authority, Larry Lamb, Peggy Hurst, Michelle Kanter, Gregory Peck, Jim Flynn and Rick Battson. 

Thanks also to expert support from Dan Kraus, Mike Nelson and Paul Smith.

 Assistance for this project was provided by the Ministry of Natural Resources.


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