Eagles are magnificent birds of prey, recognized globally as apex predators. Their powerful physique and sharp vision allow them to capture a wide array of prey in diverse habitats. This predatory nature leads people to wonder how far down the food chain their diet extends, specifically whether these large raptors consume small, ground-dwelling invertebrates like earthworms.
The Definitive Answer: Foraging Habits and Prey Size
The simple answer to whether eagles eat worms is no, as these invertebrates do not align with the energetic demands of a large raptor. An adult eagle requires significant caloric intake daily to maintain its high metabolism and sustain flight. The energy expended locating and capturing a small earthworm would far outweigh the minimal nutritional return, making this food source inefficient. Eagles possess specialized features designed for capturing and dismembering larger prey, not for probing soil. Their massive, curved talons and sharply hooked beaks are adapted for gripping and tearing meat, which is incompatible with the meticulous searching required to find earthworms.
Primary Prey: What Eagles Hunt and Scavenge
Eagle diets are primarily composed of high-protein, high-calorie sources that offer a substantial energy payoff for the effort of the hunt. For instance, the diet of the North American Bald Eagle is heavily reliant on fish, which can constitute up to 90% of its food intake, especially near coastal or inland waterways. These birds often target species like salmon, trout, or bottom-feeding catfish, which they snatch from the water’s surface using their powerful talons.
Other eagle species, such as the Golden Eagle, frequently target small to medium-sized mammals. Their diet includes rabbits, hares, ground squirrels, and even larger prey like young deer or mountain goats, depending on the region. These raptors demonstrate incredible strength, sometimes carrying prey that equals their own body weight back to their nests.
Beyond hunting, scavenging plays a significant role in the sustenance of many eagle populations. Carrion, or decaying animal remains, is readily consumed, particularly during lean times. This opportunistic consumption of already deceased animals allows them to conserve energy that would otherwise be spent on a strenuous hunt.
Species Variation and Opportunistic Feeding
While the general dietary rules apply across the genus, specific diets vary considerably based on the eagle species and their local ecosystem. Sea eagles, like the Steller’s Sea Eagle or the White-tailed Eagle, naturally concentrate their efforts on marine life, including fish, seabirds, and crabs. In contrast, the Golden Eagle’s preference for terrestrial prey means it will rarely seek out aquatic food sources.
Eagles are highly opportunistic feeders, meaning they take advantage of accessible food sources beyond standard hunting practices. This behavior frequently manifests as kleptoparasitism, where an eagle steals a catch from another bird, such as an osprey. While this opportunism might extend to eating larger invertebrates like snakes, turtles, or large insects, it does not lower the threshold to include earthworms as a viable food source.