Mallard Tubes
Giving Nature a High-Rise Advantage
Developed and provided to Hullett Marsh courtesy of Delta Waterfowl, these elevated nesting structures are specifically engineered to solve the primary threat to mallard populations: nest predation. By placing a hay-lined wire cylinder atop a steel pole over open water, we create an sanctuary that effectively increases nesting success rates from a typical 15% on the ground to over 80%. This tunnel-like system provides overhead protection from avian predators like hawks and predator baffles on the poles prevent access ground-based predators like Raccoons and Mink. Combined, these structures allow Mallards to thrive in areas where quality cover and nesting opportunities may be lacking.
Habitat Housekeeping
When Hullett freezes over, our team navigates the ice to perform vital winter maintenance on each of our 25 active Mallard tubes, clearing weathered debris and packing them with fresh, insulating grasses. During this process, we record unhatched eggs and shell fragments to calculate success rates, which informs our adaptive management strategy of moving tubes to more productive locations. Every survey also includes an inspection of the mounting poles to ensure they remain a sturdy, foolproof barrier against climbing predators, guaranteeing a secure environment for the hens returning in the spring.