Chain Lakes (AB026)

Chain Lakes (AB026)

Hanna, Alberta

Description du site

The Chain, Spiers and Farrell lakes are located 20 to 40 kilometres northwest of Hanna, Alberta. They are a complex of shallow alkali lakes, some of which are ephemeral in nature. The surrounding landscape consists of grassy meadows, aspen parkland, and alkali springs that feed small wetland areas. The Chain Lakes consists of a series of eight small wetlands extending in a line northwest from the Dowling Lake IBA. Each lake is numbered sequentially from east to west; the first and third lakes are named Pearl and Clear, while the others remain unnamed. Chain Lake #4 has 10 to 30 m wide beaches of alkali and gravel, while the beaches of Chain Lake #6 are wider, and are composed of firm gravel and sand with only small quantities of alkali beach. Spiers Lake, about 5 km to the north, is a freshwater lake with a narrow gravel bar and a shoreline that is mostly vegetated. Farrell Lake is located immediately to the west. This lake contains mudflats that are attractive to migrant shorebirds.

Oiseaux

The series of lakes that comprise this IBA support significant numbers of nesting Piping Plovers (identified as nationally endangered and globally vulnerable). Between 1986 and 1996 an average of 16 plovers were recorded at all the sites (based on counts from seven years). This total would represent about 1% of the Canadian portion of the Great Plains Piping Plover population. Chain Lake #4 is consistently the most significant with as many as 24 adult Piping Plovers being present in 1995. Spiers Lake supports nesting plovers on an occasional basis, with one nest in 1986 and 1991. Another shorebird, the American Avocet, has been seen here in large numbers in the spring (up to 350 on one lake).

Large numbers of geese utilize these wetlands and lakes during fall migration, with greater than 15,000 recorded in the 1980s at Spiers Lake, and over 5,000 recorded at Farrell Lake. In the summer, both Bairds Sparrows and Spragues Pipits breed in the grasslands surrounding the lake.

Enjeux de conservation

Shallow lakes, such as those found at this site, may dry up for extended periods, because water levels are dependent on winter snow pack and spring rains. Nonetheless, water level fluctuations due to climatic variations are a natural part of these ecosystems, which in turn lead to fluctuating numbers of plovers.

Disturbance of the shore soils and vegetation by cattle is a problem that is ongoing at many Piping Plover sites including this site. At some sites, fencing has been used to exclude cattle, but this measure has not yet been used here. At the Chain Lakes, human disturbance and the use of ground and surface water are also concerns.

The northwest corner of Spiers Lake is a National Wildlife Area and both Spiers Lake and the Chain Lakes are listed as potential Western Hemisphere Shorebird Reserve Network site under the endangered species category.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection

• Pluvier siffleur24 (max.)
• Oiseaux aquatiques20 000 (max.)