7.0 Wetland Dynamics on the Long Point Bay

Previous chapters have dealt quite extensively with human impacts on the health of the Long Point Bay ecosystem and associated wetlands. This chapter deals solely with actual wetland loss at Long Point and the ecological implications of this loss.

7.1 Relative importance of Long Point for staging and breeding waterfowl:

Figure 7.1 Distribution of Major Waterfowl Habitat Complexes along the Great Lakes Coasts.

Figure 7.2 Long Point Bay - Ownership and Location of Hunting Clubs.

Table 7.1 Average Number of Waterfowl Use-days (X 1,000) in Great Lakes Coastal Wetlands During Spring (S) and Fall (F) Migration. Adapted from Prince et al. 1992.

Table 7.2 Estimated Number of Breeding Pairs of Dabbling Ducks in Major Coastal Wetland Complexes of the Great Lakes. Adapted from Prince et al. 1992.

Some of the greatest values for coastal wetlands lie in their habitat potential for migratory waterfowl (Smith et al. 1991). Consequently it is of great concern that coastal wetland loss on the Great Lakes has been substantial, with only about 20-25% of the original wetland area of western Lake Ontario remaining (Whillans 1982). Over 95% of western Lake Erie's coastal wetlands have been lost (Herdendorf 1987), and what little remains of the existing wetlands continues to receive pressure from accelerating coastal development.

Despite the drastic decline in availability of wetlands in the last half century, the Great Lakes region continues to supply essential staging habitat for migrating ducks, geese and swans. In fact, 15 coastal Great Lakes wetlands have been identified as key staging areas for migratory waterfowl (Figure 7.1)(Prince et al. 1992). Long Point receives the highest combined spring and fall waterfowl use of the 15 identified key coastal wetlands (Table 7.1). This extensive use by migratory ducks, geese and swans can be attributed to Long Point's unique southerly location, as well as the fact that it, unlike most other coastal wetlands, has not been extensively drained or reclaimed for human use. The importance of Long Point is reinforced by the fact that the Eastern Habitat Joint Venture of the North American Waterfowl Management Plan has listed the wetlands associated with Long Point as a priority for securement (EHJV 1994).

Figure 7.1 Distribution of Major Waterfowl Habitat Complexes along the Great Lakes Coasts.

1. Chequamegon Bay 2. Portage Entry 3. Bay de Noc 4. Green Bay 5. West Michigan 6. St. Mary's River 7. Georgian Bay 8. Saginaw Bay 9. St. Clair Delta 10. Detroit River 11. Southwest Lake Erie 12. Point Pelee/Rondeau Bay 13. Long Point 14. Southcentral Lake Ontario 15. Northeast Lake Ontario. From Prince et al. 1992.

Table 7.1 Average Number of Waterfowl Use-days (X 1,000) in Great Lakes Coastal Wetlands During Spring (S) and Fall (F) Migration. Adapted from Prince et al. 1992.

The two most common nesting species at Long Point are Mallard and Blue-winged Teal, (McCracken et al. 1981), while Redheads also irregularly breed in Great Lakes coastal wetlands (Reeves 1991a). The Black Duck probably once was the most common nesting duck at Long Point (Snyder 1931); unfortunately it probably no longer breeds in the area (Prince et al. 1992). The low reproductive success of waterfowl at Long Point has been attributed to intense predation on eggs and young (Munroe 1965). However, in terms of continental waterfowl production, Great Lakes coastal wetlands have probably always been of relatively minor importance because the region is on the periphery of the breeding range of many species (Prince et al. 1992).

Also, it has been suggested that frequent and substantial water level fluctuations on the Great Lakes (see Chapter 2) tend to flood out nearshore and overwater nests (Prince et al. 1992). Consequently, Long Point probably never was an important breeding area for waterfowl. Thus, while Long Point is the most important of the 15 identified key Great Lakes wetlands from a staging aspect, it is one of the least important from a waterfowl reproduction standpoint (Table 7.2). Also, with the occasional exception of Wood Ducks, molting waterfowl have not been reported at Long Point in large numbers (D. Dennis, CWS, 1992 personal communication, from Prince et al. 1992).

Table 7.2 Estimated Number of Breeding Pairs of Dabbling Ducks in Major Coastal Wetland Complexes of the Great Lakes. Adapted from Prince et al. 1992.