|Map Sheets||83H/7, 8, 9, 10|
|Lat / Long||53.4500000, -112.5333333|
|Max depth||2.3 m|
|Mean depth||No Data m|
|Dr. Basin Area||1,970 km2|
|Drainage Basin||North Saskatchewan River Basin|
|TP x||No Data µg/L|
|CHLORO x||54.0 µg/L|
|TDS x||922 mg/L|
Beaverhill Lake is one of the most important bird habitats in Alberta. It is recognized as an internationally significant water body for shorebirds and waterfowl, in particular, as a staging area for migratory birds flying to and from the arctic. During May and September each year, the lake hosts thousands of birds. In the spring, most of the birds move on, but many others stay and nest. Beaverhill Lake and the surrounding area have been Ducks Unlimited (Canada) projects since early 1969. In 1981, the Canadian Nature Federation designated the lake as a National Nature Viewpoint in recognition of its importance to birds and birdwatchers, and in 1982, the lake became part of the Wetlands for Tomorrow Program. This is a joint program between Ducks Unlimited (Canada) and Fish and Wildlife Division for the management and enhancement of waterfowl populations and habitats. In June 1987, the lake was designated a Ramsar site. The Ramsar Convention of 1971 is an international agreement that identifies and protects wetlands of importance to migratory birds. By 1988, the convention had been ratified by 45 countries. The secretariat for the convention is the Switzerland-based International Union for the Conservation of Nature and Natural Resources.
Beaverhill Lake is situated in the counties of Beaver and Lamont. It is easily accessible from the city of Edmonton, as it is located only 65 km east of the city, just north of Highway 14 and east of Secondary Road 834. The closest population centre is the town of Tofield, 4 km southwest of the lake on Highway 14 (FIGURE 1).
The lake's name is a translation of the Cree name, amisk-wa-chi-sakhahigan (Holmgren and Holmgren 1976). The lake appears on the Thompson map of 1814 as Beaver Lake. This map also shows the nearby Beaver Hills, now known as the Cooking Lake Moraine, which were named for the large number of beaver found there.
According to legend, the lake was a favourite camping spot for Cree when they came to the area to hunt buffalo. In the late 1800s and early 1900s, settlements were established in four areas near the lake. The western shore was first settled by Métis, who came to hunt buffalo in the early 1870s (Touchings 1976). Many of the Métis families later filed for homesteads and began farming. White settlers arrived in the area during the 1880s and occupied land along the western shore. One of the first settlers to acquire land legally was Robert Logan, who operated a store and trading post and owned land near the lake. The district soon became known as Logan, and the Logan post office was established in 1892. Robert Logan's son, John, promoted the lake as a pleasure resort, and operated a steamboat that carried vacationers across the water (Lister 1979). The second area, Beaverlake Settlement, was located on the northeast shore just east of the lake's outlet, Beaverhill Creek. This area was settled sometime after 1873, and by 1892, the settlement boasted a school and a one-man detachment of the North West Mounted Police. The third area, Bathgate, was located on the southeast shore; it was settled around 1900. The Bathgate post office opened in 1906 but closed in 1927 after the community failed to expand. The fourth settlement was the village of Tofield, located 4 km southwest of the lake. It was the fastest growing community in the area in the 1900s. In 1907, Tofield was incorporated as a village, and in 1909, after the arrival of the Grand Trunk Pacific Railroad, it became a town (Touchings 1976). At the present time, Tofield is the only one of the four communities that still exists.
The birds of Beaverhill Lake have been studied by many ornithologists since the beginning of the twentieth century. In particular, long-term observations were made by the late Professor William Rowan and the late Robert Lister, both from the Zoology Department of the University of Alberta. Beginning in 1920, Rowan spent 37 years collecting, sketching and banding birds and making extensive notes on their behaviour. He combined two contradictory attitudes toward wildlife: that of the hunter/collector and that of the naturalist/conservationist. In 1925, the lake was declared a Public Shooting Ground, but by 1948, when the Edmonton Bird Club was founded, most visitors to the lake were more interested in identifying and observing birds than shooting them (Lister 1979). The Edmonton Bird Club has contributed much to the knowledge of the species of birds at the lake. In 1983, another group of birding enthusiasts began the Beaverhill Lake Bird Banding Station to encourage research and to provide instruction in ornithology. The group was named the Beaverhill Bird Observatory in 1985. Members carry out many projects, including daily counts of birds, construction of nesting boxes, banding, and research on the behaviour and habitat of individual species (Ebel 1988).
During the 1970s, management of the Beaverhill Lake area became a subject of concern to the Fish and Wildlife and Public Lands divisions of Alberta Forestry, Lands and Wildlife, Alberta Agriculture, local leaseholders and the general public. In 1981, the Beaverhill Lake Integrated Resource Plan was approved (Alta. En. Nat. Resour. 1981). It allocated the approximately 4 450 ha of Crown land around the lake according to 5 land-use themes: agriculture, agriculture-wildlife, wildlife-agriculture, wildlife and recreation. Theme areas are used to prepare a local development plan for each disposition. The local development plan then forms the basis for range improvement agreements between the government and the lessee or permittee, or for wildlife habitat enhancement or recreation projects.
In 1987, Alberta Forestry, Lands and Wildlife established the Beaverhill Natural Area to protect parts of Beaverhill Lake and the surrounding area (Alta. For. Ld. Wild. 1987). The natural area comprises the Dekker and Pelican islands at the north end of Beaverhill Lake and land surrounding Robert Lister Lake, also known as "A" Lake (FIGURE 1). It is managed through the cooperation of the Fish and Wildlife and Public Lands divisions of Alberta Forestry, Lands and Wildlife, Ducks Unlimited (Canada) and the Beaverhill Bird Observatory. Although the natural area is conserved and managed to maintain its wilderness and wildlife qualities, recreational and educational use is encouraged. Popular activities are birdwatching, photography and hiking.
There are several points of access to the shore of Beaverhill Lake, but most of them must be reached on foot. The route to the southern side of the lake begins in Tofield (FIGURE 2). Turn left off Highway 14 and then immediately right onto the Tofield access road. Turn left again at the gas station. The Beaverhill Lake Nature Centre is located next to the gas station. It provides field checklists for birds, nesting boxes, seed and tourist information. Once over the railroad tracks, turn east onto Rowan's Route, which is also called 51 Avenue within Tofield, and Secondary Road 626 outside the town. About 5 km east of Tofield, a north-south road allowance provides a short, direct route to Francis Point on the southern side of the lake. The turnoff is marked with a sign. At the far eastern end of Rowan's Route is the access to Robert Lister Lake and the natural area. When you have driven almost 9 km from Tofield, turn north off the road. Close the gate upon entering the pasture, then drive northeast over a cart-track that ends in an informal parking area at another gate. Motor vehicles are not allowed past the parking area. There is a large sign on the other side of this gate that shows a map of Beaverhill Lake. A cart track leads from the sign along the western shore of Robert Lister Lake, and terminates at a Ducks Unlimited (Canada) weir. Another trail runs from the weir along the southern shore of Beaverhill Lake to Francis Point.
Robert Lister Lake is an impoundment developed by Ducks Unlimited (Canada) to control water levels and provide nesting habitat for waterfowl. Approximately 26 islands have been built around the southern and eastern sides of the lake; they have been well used by nesting ducks and geese since their construction. The headland on the western side of the weir is one of the best locations for viewing shorebirds. The Beaverhill Lake Banding Station is situated near the western side of the weir, as well.
Kallal's Ponds are located at the Kallal Dam on Amisk Creek, just south of Robert Lister Lake (FIGURE 2). During migration, waterfowl, blackbirds, marsh-dwelling birds and sandpipers congregate on the ponds (Heath et al. 1984). Another area enhanced by Ducks Unlimited (Canada) is a marsh called "C" Lake, which is located near the southeastern shore of Beaverhill Lake, approximately 2.2 km northeast of the weir on Lister Lake. To create waterfowl nesting habitat, about eight islands were built around the perimeter of the marsh. The marsh is connected to Beaverhill Lake by a drainage ditch.
Access to the Beaverhill Lake Recreation Area, midway along the eastern shore, can be gained from Secondary Road 855 (FIGURE 1). This area is operated by the County of Beaver, and has a picnic shelter and outdoor toilets. In 1988, however, they were in need of repair. Motor boats are not allowed on Beaverhill Lake, but canoes and rowboats are permitted (Alta. For. Ld. Wild. 1988). The lake is popular for waterfowl hunting, but hunting restrictions are in effect over the southern half of the lake. Hunting game birds on the southern portion of the lake and the southern islands, or hunting within 0.8 km of the edge of the water of that portion of the lake, is prohibited until 1 November each year (Alta. For. Ld. Wild. 1989).
A large portion of Beaverhill Lake's drainage basin lies within the Cooking Lake Moraine (Alta. Envir. 1977). This landform occupies most of the central and western parts of the watershed. It is characterized by knob and kettle topography that gives it a gently to strongly rolling appearance. The knobs range from 5 to 15 m in height, and many of the kettles contain water. In general, the moraine slopes downward to the northeast. The eastern and southern parts of the drainage basin are a poorly drained ground moraine plain. Intermittent and permanent sloughs and lakes are present throughout this area.
The Cooking Lake Moraine contains the largest tracts of continuously forested land within a 30-km radius of Edmonton (Alta. Envir. 1977). The moraine is part of the Boreal Mixedwood Ecoregion (Strong and Leggat 1981). The soils are mainly Orthic Gray Luvisols and the forest cover is mostly deciduous, with trembling aspen the dominant tree (TABLE 1). White spruce is the climax species but, because of land clearing during the late 1800s, timber harvesting and fire, few mature stands of spruce remain. Mature trembling aspen forest predominates in the southern part of the moraine, as well as in Elk Island National Park and the Cooking Lake-Blackfoot Grazing, Wildlife and Provincial Recreation Area in the northern part of the moraine.
The ground moraine plain in the eastern and southern parts of the drainage basin has relatively little tree cover. This area is part of the Aspen Parkland Ecoregion, and the natural vegetation consists of trembling aspen interspersed with patches of grassland (Strong and Leggat 1981). Much of the land, however, has been cultivated since the early 1900s. The soils are fertile Black Chernozemics that are used to grow barley, oats and canola crops (Alta. En. Nat. Resour. 1981; Howitt 1988).
Approximately 90% of the 4,450 ha of Crown land surrounding the lake is leased for agriculture, primarily grazing, and the private land nearby is used to grow crops. In 1981, there were 35 grazing leases, 5 grazing permits, 7 cultivation permits and 6 farm development leases assigned to approximately 44 farmers and ranchers who own adjacent lands. A recreational lease for the Beaverhill Lake Recreation Area on the eastern shore is held by the County of Beaver. As well, there were 12 producing and 13 potential natural gas well sites in the area in 1981 (Alta. En. Nat. Resour. 1981).
The development of country residential subdivisions in the western portion of the drainage basin increased dramatically during the 1970s and 1980s. Closer to the lake, however, residential development has been minimal.
Most of the creeks draining into Beaverhill Lake flow intermittently. Amisk Creek drains the southern part of the watershed and flows over two Ducks Unlimited (Canada) weirs into Robert Lister Lake. Norris, Wakinagan, Hastings and Katchemut creeks drain the Cooking Lake Moraine and flow intermittently into the western side of Beaverhill Lake. The outlet, Beaverhill Creek, is overgrown with cattails and flows only during periods of very high water. It eventually drains into the North Saskatchewan River.
The large size (139 km2) and shallow depth of Beaverhill Lake, as well as the presence of several islands, are some of the physical features that attract birds to the lake. There are no depth contours available, but the shape of the lake basin is that of a large, shallow pan with a maximum depth of 2.3 m (TABLE 2). The number and size of the islands at the north end of the lake, which include the Dekker and Pelican islands (FIGURE 1), vary with the water level.
The character of the shoreline is variable. The southern shore is quite straight and has narrow, sandy beaches, whereas the northern shore is muddy and irregular in shape, and is characterized by reed-choked bays and rock-strewn points. The lake is bordered by willow and trembling aspen in the east and south, but in the west and north the landscape is open and consists of pasture and gently sloping fields (Dekker 1982).
The elevation of Beaverhill Lake has been monitored since 1968 (FIGURE 3). The minimum recorded level (668.23 m) occurred in that year, and the maximum level (669.60 m) was recorded in 1974. An interesting anecdotal history of long-term water levels in Beaverhill Lake is given by Lister (1979). In 1885, the lake's elevation was so low that buffalo had to drink from springs in the centre of the basin, and willow and poplar trees grew on the accrued land. By 1895, the water level had risen high enough to flood the trees, and Great Blue Herons nested in their dry, dead branches. The period between 1899 and 1903 was very rainy, and the lake level of approximately 670.9 m achieved in 1902 may have been the highest of the past century. From 1905 to 1910, the lake receded, and much of the previously submerged land was cultivated. Water levels remained stable until the rainy fall of 1915, when they began, once again, to rise. The highest level for this period was approximately 670.3 m in 1917 (Zelt and Glasgow 1976). By 1922, the lake had receded to levels similar to those of 1910. In 1929, the elevation dropped about 1.5 m, and the following winter most of the fish population died. Water levels remained low for more than two decades, and in 1950 and 1951, the lake almost dried up completely. By 1974, the elevation had risen to 669.60 m, but it declined again during the late 1970s, and has remained quite stable since that time (FIGURE 3).
At various times, Lister Lake has been either an integral part of Beaverhill Lake, a dry mud flat, or various stages in between. In 1917, it was a large, wide bay at the southeast end of the lake (Zelt and Glasgow 1976), whereas in the 1950s, a car could be driven across its dry bottom (Lister 1979). In 1970, it was a water-filled slough, and Ducks Unlimited (Canada) built a weir between it and Beaverhill Lake (FIGURE 1). To encourage waterfowl production, they also constructed artificial islands and nesting platforms. High water levels during the spring of 1974 washed out the weir, but it was reconstructed soon after. The present structure is an earthen berm with a concrete spillway.
The water quality of Beaverhill Lake was studied by researchers at the University of Alberta during 1971 and from 1974 to 1976 (Alta. Envir. n.d.[a]).
The water is well-buffered and slightly saline (TABLE 3). The dominant ions are bicarbonate, sulphate and sodium. The lake is so shallow that it is mixed constantly by wind during the open-water period. In 1975, the water column was weakly thermally stratified during June, but isothermal for the rest of the open-water period (FIGURE 4). The concentration of dissolved oxygen was high during the summer and fall of 1975 (FIGURE 5), but declined over winter until, by February 1976, the concentration was 2.4 mg/L at the surface and 1.8 mg/L at a depth of 0.5 m.
Beaverhill Lake is hyper-eutrophic. In 1975, the average Secchi depth was only 0.4 m and the average chlorophyll a concentration was 54 µg/L. The highest chlorophyll level (137 µg/L) was recorded in August (FIGURE 6). Data for total phosphorus concentrations are not available, but the high chlorophyll levels suggest that total phosphorus levels would be very high as well. Major potential sources of phosphorus are runoff from agricultural land, particularly pasture land near the shore, inputs by the tens of thousands of birds that use the lake, return of phosphorus from sediments to the water column, and phosphorus released by senescing macrophytes.
Qualitative studies of the plant community in Beaverhill Lake were conducted by researchers at the University of Alberta from 1974 to 1976 (Alta. Envir. n.d.[a]). Of the eight algal genera identified, three were green algae (Chlorophyta: Ankistrodesmus sp., Chlamydomonas sp., Crucigenia sp.) and three were blue-green algae (Cyanophyta: Anabaena spp., Aphanizomenon sp., Microcystis sp.). Macrophytes were sampled in June 1975. The three emergent species identified were common great bulrush (Scirpus validus), sedges (Carex spp.) and rushes (Juncus spp.), and the two submergent species were large-sheath pondweed (Potamogeton vaginatus) and mare's tail (Hippurus vulgaris).
The zooplankton community was sampled regularly from November 1974 to July 1976 by the University of Alberta (Alta. Envir. n.d.[a]). During the open-water period in 1976, the average biomass was 2.5 g/m2. Copepods, in particular Diaptomus sp., were present in large numbers on all sampling dates except 2 June. On that date, the planktonic rotifer Conochilus unicornis was dominant numerically. In August, Daphnia pulicaria shared dominance with Diaptomus sp.
There are no data available for the benthic invertebrate community.
There are no sport fish in Beaverhill Lake. Because of the lake's shallow depth, dissolved oxygen becomes depleted over winter and most fish are unable to survive. Historically, northern pike, whitefish and suckers inhabited the lake, which supported a good fishery when water levels were high. At present, however, only minnows and sticklebacks can survive the winter (Lister 1979; Dekker 1982).
Beaverhill Lake is one of the major staging areas in western North America for waterfowl and shorebirds bound to and from the western Arctic. By 1988, 272 species of birds had been reported in the area of the lake (Ebel n.d.). Of these, 145 species are known to breed locally. Dekker (1982) gives an excellent overview of the timing of various migrations and the locations of locally nesting birds and migrants. In years with an early spring, the first Canada Geese arrive before mid-March. Locally breeding pairs are followed by transient "honkers", then later by White-fronted and Snow geese. Their numbers can reach tens of thousands at peak periods. Most Sandhill Cranes arrive in late April or early May, and stragglers continue to come for two weeks. Shorebirds, including Greater and Lesser yellowlegs, Short-billed and Long-billed dowitchers, Hudsonian Godwits and Pectoral Sandpipers, congregate on flooded fields and wet meadows before the lake is free of ice. As meltwater pools evaporate, flocks of waders congregate on mudflats along the lakeshore. The number and variety of shorebirds increase toward mid-May, when great numbers collect on pastureland to feed on newly hatched midges. Different areas of the lake are used by various species of waders. Sandpipers are found in the greatest numbers along the open western shore, whereas Sanderlings are attracted to the wave-swept strip of sand along the southern shore. Dowitchers, yellowlegs and Stilt Sandpipers favour shallow bays, Black-bellied Plovers, Knots and Ruddy Turnstones frequent rock-strewn points along the eastern shore, and American Golden Plovers and Buff-breasted Sandpipers use the nearby grasslands. After the northern shorebirds depart, locally breeding waders, such as American Avocets, Marbled Godwits, Willets, Wilson's Phalaropes, Killdeer, and a few Piping Plovers, remain.
Other birds that nest at the lake include Canvasbacks, Pintails, Mallards, Ruddy Ducks, American Coots and grebes. The distribution of ducks, geese and swans was surveyed during the fall of 1973 and the spring and summer of 1974 by the Canadian Wildlife Service (Kemper 1976). The greatest number of birds are present during spring and fall, but because Beaverhill Lake is a major duck moulting area, duck numbers increase substantially in July and August when birds that have nested in nearby potholes move from the potholes to the lake to moult. Other ducks breed on the lake itself, and their numbers increase when ducklings hatch. Most of the ducks are dabblers rather than divers; they primarily frequent the marshy shorelines at the northern end of the lake during July and August.
During summer, thousands of Red-winged and Yellow-headed blackbirds and Franklin's gulls raise their young in the cover of bulrushes. Ring-billed and California gulls, terns, Black-crowned Night Herons, Great Blue Herons, White Pelicans and Double-crested Cormorants nest on islands (Dekker 1982). Two groups of islands are part of the natural area. The Dekker Islands (FIGURE 1) consist of three islands at the northern end of the lake. The two southern islands are included in the natural area; the largest of these two islands has hosted a nesting colony of Great Blue Herons, but since 1980, the colony has been inactive (Folinsbee 1988). The Pelican Islands are a group of very small islands near the eastern shore. Their number varies depending on water levels. They support nesting colonies of pelicans and cormorants. Access to the Pelican Islands is prohibited by The Wildlife Act (Alta. En. Nat. Resour. 1981).
While local birds are still raising young, migrants from the north begin to arrive. Least Sandpipers appear by mid-July, followed by Semipalmated Sandpipers and a few plovers. Northern Phalaropes start to build up substantial flocks far out on the lake during summer, although they do not reach the large numbers seen in late May. By early August, parts of the lake are crowded with Dowitchers, yellowlegs, Stilt and Pectoral sandpipers (Dekker 1982).
Rare birds that have been sighted at the lake include Surfbirds, Sharp-tailed Sandpipers, Ruffs, Western Sandpipers, Wandering Tattlers, Black-necked Stilts, Common Egrets, Sabine's Gulls, Black Brants and Long-tailed Jaegers (Dekker 1982). During the summer of 1988, about 15 juvenile Trumpeter Swans were recorded on the lake.
Birds of prey such as Red-tailed, Swainson's and Cooper's hawks are plentiful in late summer and fall, and Parasitic Jaegers are recorded in most years. Shorebird numbers begin to decline by October, although some remain until freeze-up. Small passerines such as longspurs and buntings, on the other hand, are more plentiful than ever in October (Dekker 1982). From September to early October, very high concentrations of ducks mass along the southern shore where a bait station is located. The station, which is operated by Fish and Wildlife Division, feeds grain to ducks to minimize damage to nearby crops. Public access to the station is prohibited. The best staging areas for geese are along the northern and western sides of the lake, although smaller flocks use pastures along the southwestern and southeastern shores. Whistling Swans are the last large group to arrive. Thousands of these birds line the shores and dredge for the roots of aquatic plants. Many remain until November when ice begins to form (Dekker 1982).
Beaverhill Lake is an important area for ungulates. The northern, eastern and southern shores provide wintering habitat for white-tailed and mule deer (Alta. En. Nat. Resour. 1981). A census of the muskrat population conducted during the autumn of 1974 recorded 65 muskrat houses along the shoreline, and the population was estimated to be at least 390 muskrats (Zelt and Glasgow 1976).
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-----. n.d.[c]. Tech. Serv. Div., Surv. Br. Unpubl. data, Edmonton.
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-----. 1988. Boating in Alberta. Fish Wild. Div., Edmonton.
-----. 1989. Guide to game bird hunting. Fish Wild. Div., Edmonton.
Alberta Research Council. 1972. Geological map of Alberta. Nat. Resour. Div., Alta. Geol. Surv., Edmonton.
Dekker, D. 1982. An introduction to Beaverhill Lake. Alta. Nat. 12:1-5.
Ebel, G.R. n.d. Birds of the Beaverhill Lake area: A field checklist. Beaverhill L. Nat. Centre, Tofield.
-----. 1988. The Beaverhill Bird Observatory, Edmonton. Pers. comm.
Energy, Mines and Resources Canada. 1983. National topographic series 1:250 000 83H (1983). Surv. Map. Br., Ottawa.
Environment Canada. 1982. Canadian climate normals, Vol. 7: Bright sunshine (1951-1980). Prep. by Atm. Envir. Serv. Supply Serv. Can., Ottawa.
Folinsbee, J. 1988. Alta. For. Ld. Wild., Fish Wild. Div., Dist. Office, Edmonton. Pers. comm.
Heath, R., G.R. Ebel and M. Cox. 1984. Beaverhill Lake gazeteer. The Edm. Bird Club, Edmonton.
Holmgren, E.J. and P.M. Holmgren. 1976. Over 2000 place names of Alberta. 3rd ed. West. Producer Prairie Books, Saskatoon.
Howitt, R.W. 1988. Soil survey of the County of Beaver. Alta. Soil Surv. Rep. No. 47. Alta. Res. Counc., Terrain Sci. Dept., Edmonton.
Kemper, J.B. 1976. Implications for waterfowl and migratory birds [Appendix 7]. In Cooking Lake area study, Vol. IV: Ecology. Alta. Envir., Plan. Div., Edmonton.
Lister, R. 1979. The birds and birders of Beaverhills Lake. The Edm. Bird Club, Edmonton.
Strong, W.L. and K.R. Leggat. 1981. Ecoregions of Alberta. Alta. En. Nat. Resour., Resour. Eval. Plan. Div., Edmonton.
Touchings, D. 1976. Heritage resource inventory of the Cooking Lake study area [Appendix 10]. In Cooking Lake area study, Vol. V: Economic base and heritage resources. Alta. Envir., Plan. Div., Edmonton.
Zelt, K.A. and W.M. Glasgow. 1976. Evaluation of the fish and wildlife resources of the Cooking Lake study area [Appendix 6]. In Cooking Lake area study, Vol. IV: Ecology. Alta. Envir., Plan. Div., Edmonton.