The bufflehead, a small diving duck, is recognizable by its distinctive large head and compact body. These ducks are commonly found across North America, inhabiting a variety of aquatic environments, including small ponds, lakes, rivers, and coastal areas during winter. Their presence often indicates healthy aquatic ecosystems, where they actively forage for food.
Main Food Sources
Buffleheads are primarily carnivorous divers, with their diet largely consisting of aquatic invertebrates. In freshwater habitats, they consume insect larvae, such as midges, dragonflies, and damselflies, along with water boatmen, mayfly, and caddisfly larvae. In saltwater environments, their diet shifts to crustaceans like shrimp, amphipods, and isopods, and mollusks such as snails and mussels.
Buffleheads may also consume small fish, including sculpins and ratfish, or fish eggs, particularly when other prey is scarce. This opportunistic feeding allows them to adapt to varying food availability. They occasionally ingest small amounts of aquatic plant material, such as seeds from pondweeds and bulrushes, especially in fall and winter, but this constitutes a minor part of their overall diet.
Foraging Techniques
Buffleheads are highly skilled divers, a key part of their foraging strategy. They disappear underwater quickly and can resurface in unexpected locations. Their powerful legs, set far back on their bodies, act as effective propellers, allowing them to move efficiently through water. Unlike many other ducks, their small wings are also adapted for propulsion underwater, though they hold them tightly against their bodies during dives.
They primarily forage in shallow waters, usually less than 15 feet deep, but can dive deeper if necessary to pursue prey. Buffleheads are visual hunters, relying on their keen eyesight to spot invertebrates and small fish underwater. They often swallow smaller prey while still submerged, a behavior that helps prevent other birds from stealing their catch. Dives typically last about 12 seconds, though they can hold their breath for up to 25 seconds.
Dietary Adaptations
The diet of buffleheads varies based on seasonal availability and their specific habitat. During warmer months and in freshwater environments, aquatic insects and their larvae are more prevalent. As seasons change, especially in winter, those in coastal areas switch to consuming more crustaceans and mollusks. This dietary flexibility allows them to thrive in diverse locations across North America.
The type of water body also influences their food choices; for instance, inland ponds offer different prey than brackish estuaries. Ducklings initially feed on smaller, more easily digestible prey and may dabble at the water’s surface instead of diving. As they mature, their diet gradually shifts to include the larger invertebrates and small fish consumed by adults. Their small, pointed bill is well-suited for grasping the slippery, small prey they capture underwater.