5.0 Submerged Aquatic Plants on Long Point Bay

5.1 Introduction

Staging areas are extremely important for north-temperate and arctic-breeding waterfowl, as the body fat that birds acquire on these wetlands provides a crucial energy source during egg laying and incubation, as well as during spring and fall migration. However, a large proportion of North America's staging areas have been drained, while many on the Great Lakes have been degraded to the point where the loss of aquatic macrophytes has decreased their carrying capacity for staging waterfowl (Dennis et al. 1984; Crowder and Bristow 1988). This has precipitated drastic declines in the numbers of waterfowl using affected wetlands, thereby increasing the importance of remaining mid-continental wetlands for feeding and resting waterfowl. Therefore, it is important to manage and maintain the aquatic vegetation on remaining wetlands as a food source for migratory waterfowl. Long Point's relatively pristine state, as well as its unique geographic location on the Atlantic flyway between Gulf and Atlantic coast wintering areas and Arctic and Prairie breeding areas, makes it one of the most important waterfowl staging areas in North America. Long Point's productive wetlands receive the highest waterfowl use of any area on the Great Lakes, regularly supporting hundreds of thousands of waterfowl during spring and fall migration (Chapter 8). From a purely nutritional standpoint, Long Point is probably particularly important for staging diving ducks. Because of their obligation to forage aquatically, they are dependent on the availability of aquatic plants to gain the body fat necessary for migration and reproduction. Therefore, the availability and suitability of aquatic macrophytes on Long Point Bay is extremely important for migrating waterfowl, particularly members of the tribes Aythya, Bucephala, and Mergini. The fact that Canvasbacks abandon traditionally used wintering and staging areas when preferred foods (ie. fennelleaf pondweed, wild celery, and fingernail clams) decline below a critical threshold (Trauger and Serie 1974; Munro and Perry 1983; Serie et al. 1983) underlines the importance of conserving the ecological integrity and species composition of Long Point Bay's aquatic macrophytes.