Wetlands of the
Cariboo Chilcotin
Thousands of ponds, marshes, bogs, fens and meadows dampened by flood waters and heavy precipitation dot our region. They appear within the grasslands, forests and alpine meadows of the Cariboo Chilcotin. Crucial for water storage, protecting the land from erosion, and providing valuable nutrient exchange and habitat for wildlife and fish, the wetlands play a vital role in the ecological balance. Smoothed and flattened by the glacier's massive weight, the plateaus and valley pockets of the Cariboo Chilcotin became dotted with many lakes and wetlands as the Cordilleran Ice sheet receded. Ponds and marshes appeared as the lowland began to drain off the excess melting waters.
Moistened by mineral-enriched ground water, the deep peat soils of fens that dominate our wetlands are ideal for sedge, moss and willows . Bogs receive their water only from rain and snow, so their acidic, nutrient-poor soils suit the black spruce, Labrador tea and sphagnum moss that growth ere. Wet meadows contribute to nearby streams and marshes that rise and fall with snow melt and rainstorms. These meadows, effective for storing water and cycling minerals, provide for lush plant life that soaks up excess water which would otherwise cause erosion.
An abundance of invertebrate life is found in wet meadows and marshes and feeds numerous types of birds and amphibians. Fresh water shrimp and snails are plentiful. Reptiles abound in wetlands - salamanders, frogs, toads, snakes and the blue listed* painted turtle abound in ponds and marshes. Painted turtles possess no teeth and rely on a sharp beak for chewing. They can stay submerged for long periods without breathing and in our region survive months of hibernation throughout the winter. Alteration or destruction of the painted turtles' habitat is the main threat. In Williams Lake the painted turtle may be seen basking on logs at the Scout Island marsh.
Beaver, the largest rodent in North America, - dam creeks creating ponds and marshes -sites for nesting flocks of migrating water birds. Once abandoned, beaver dams deteriorate and the marshes drain allowing new vegetation to flourish. Another rodent of the wetlands, the muskrat, feeds on the plentiful supply of cattails around marshes. The homes of the beaver and muskrat are especially visible when the ponds freeze.The moose, largest of the deer family, frequents marshes where they consume up to 14 kg (30 lbs.) of willows per day. Travelling in the bogs for moose is made easy by their long legs and cloven hooves. Their hair is hollow, allowing for more efficiency when swimming and drying out after. As well, the black bear, considered 75% vegetarian, feeds on the herbs and lush greens of wetlands.
Nesting water birds flock to the marshes and lakes in the region each spring. Canada Geese, Harlequin, Pied billed Grebes, Coots, Lesser Scaup, Mallards, Green and Blue-winged Teal, and Ruddy Duck are a few. These ducks' average flight speed is 65 to 90 km/hr. Some ducks feed on the bottom of ponds and are called divers. Divers include Goldeneye, Ruddy Duck and Lesser Scaup, and usually nest in vegetation directly over the water. Their large paddle-like feet are used to help them take off, pattering over the surface for some distance. Ducks often dive underwater from 1 to 2m, though Scaup and Goldeneye may go down to 15 metres! Another diver, the red listed Western Grebe, once nested in the Cariboo, with up to 35 breeding pairs nesting on Williams Lake. These grebes nest in vegetation along a lakeside, away from waves and human disturbances, yet near access to open water deep enough for diving. Other ducks called dabblers are shallow-water feeders, tipping their heads up to sift vegetation. Dabblers such as Mallards, Green and Blue-winged Teal "take off" directly from the water and generally have a larger wing span than divers.
Red-winged and Yellow-headed Blackbirds, Sandpipers, Killdeer, marsh wrens, Fox and White-crowned Sparrow, Yellow Throat Warblers, Barn Swallows and Flickers feed over the marshes and waterways, perching on bulrushes and tree branches as they fill the air with their songs. Little Brown Myotis bats roost in tree cavities and rock crevices close to wetlands, and fly 3 to 10m above the meadows and open water, eating hundreds of insects each night. Meadow vole abound in the meadows, leaving a network of tunnels and runways through which they escape from their predators. The red listed Peregrine Falcon hunt the wetlands, feasting on small ducks and shore birds, robins, swallows, pigeons and crows. Once a common inhabitant, nesting on cliffs overlooking wetlands, lakes and major rivers, the Peregrine Falcon are gradually re-establishing themselves, and may now be seen occasionally hunting above waters in the region.
Two of the largest birds in North America that frequent our region are the Great Blue Heron and Sandhill Crane, both reach over 1 m in height and are blue listed. They feed by the lakes and marshes on small fish, frogs, snakes and insects. The heron with it's large gray-blue body, white head with plumes, black stripe above each eye, fly with it's neck bent back. It is very sensitive to human disturbances, especially during nesting March through June. Herons prefer to nest in high trees, well away from predators, and build these huge nests with sticks. They may often be seen perched on trees or objects above a marsh, or wading in the shallow waters in search of a meal.
Sandhill cranes, a very secretive bird, nests in open areas in the fens, bogs and marshes but unlike the heron they never perch on trees. Their nests are made of grasses, rushes, and moss, and either are anchored in shallow water or lay directly on the ground. Their long legs and non-webbed feet are built for walking on the ground and in water. The bare red skin over the forehead and upper face and white cheeks stands out against the Sandhill crane's grey neck, body and wings. Cranes have a courtship ritual that has evolved over thousands of years and includes a "rattle like" call. The red markings on its head and straight neck in flight distinguished it from the heron.
Tundra Swan, Greater and Lesser Yellowlegs, Wilson's Phalarope, Herring, Ring-billed and Mew Gulls frequent the wetlands in migration period. The only nesting colony of American White Pelicans in BC is located at Stum Lake in White Pelican Provincial Park in the Chilcotin. From this nesting site, these large white birds feed on fish in shallow lakes, sometimes hundreds of kilometers away, including Alkali Lake and Williams Lake. The pelican's3 m wings are black tipped and they have orange bills and a very expandable pouch which is connected to the throat. This pouch is used not only to catch fish, but serves as a bowl in which young pelicans feed on the regurgitated fish their parents provide.
The pelicans are threatened by fluctuating water levels which will often cause a colony to be abandoned. In drought years, nesting islands become connected to the mainland, allowing access to land-based predators. Sudden noises may cause the red listed pelican to abandon their nests or in a panic crush eggs and knock over nests as they flee. Unattended eggs or nestlings are preyed on by gulls, ravens, crows, or may die from exposure to cold, rain or hot sun!
The importance of wetlands with their systems of water purification, soil enrichment and plant and wildlife habitat, is significant to maintaining a healthy balance in all the ecosystems of the Cariboo Chilcotin. Remember that nesting birds are very sensitive to disturbance and when flushed from their nests, the eggs or young are left unprotected. Birds that moult (lose their flight feathers) after nesting, must grow new feathers before they can fly again and are very vulnerable.
*Species are ranked in BC by their risk of extinction:
Red Listed means the species is endangered.
Blue Listed is a species of concern due to characteristics that make them sensitive to human activities and/or natural events.
All reference to Red and Blue listings refer to the Province of BC's Listings.
This brochure produced by the
Cariboo Chilcotin Conservation Society.
Publication support received from: the Vancouver Foundation.