CHEMICAL LIMNOLOGY AND WATERBIRD USE OF AN URBAN CONSTRUCTED WETLAND

The Sackville Waterfowl Park is a 19-ha shallow freshwater constructed wetland located in Sackville, New Brunswick, Canada. The objectives of this ongoing study are to determine the relationships between chemical limnology, primary productivity, macroinvertebrate abundance and waterbird density in this urban wetland and if these change with increasing duration of flooding. Based on total phosphorous and chlorophyll-a, this wetland would be categorized eutrophic. Annual mean concentrations of total phosphorous, total organic carbon and chlorophyll-a, did not decline during 1992-1996, a period from four to eight years after the creation of this wetland. Total nitrogen concentrations did however decline during this time period. Associated with high nutrient availability there was an abundance of macroinvertebrates with mean dry weight per activity trap ranging from 7-560 mg. Six different species of fish were caught in minnow traps, with mean number of fish caught per trap increasing from 10 to 27 during 1993-1996. The urban setting of the park has not deterred wildlife from using it, with over 160 species of birds being observed. There have been 26 species confirmed bredding in the park. There was an average of 49 broods of waterbirds produced annually during 1993-96, one of the highest reported brood densities in Atlantic Canada. These results suggest that constructing wetlands in an urban environment can create excellent wildlife habitat.