The Wedge-tailed Eagle (Aquila audax) is Australia’s largest bird of prey, found across the continent, Tasmania, and southern New Guinea. This magnificent raptor is recognized by its impressive wingspan, which can reach up to 2.84 meters, and its distinctive wedge-shaped tail. Its fully feathered legs and powerful feet make it a formidable aerial predator. Eagles often soar effortlessly to altitudes of 2,000 meters, utilizing air currents.
Main Prey
The Wedge-tailed Eagle’s diet consists primarily of mammals. Introduced species like rabbits and hares form a substantial part of their diet, often comprising 30-70% of their diet, and up to 92% in some areas. They also prey on native medium-sized marsupials, including wallabies, bandicoots, possums, and young kangaroos. They target mammals weighing over 500 grams.
Their diet also includes birds like cockatoos, magpies, ravens, and waterfowl, often birds weighing over 100 grams. Reptiles like lizards, including bearded dragons and goannas, are also eaten, especially in arid regions where they can be a key food source. They also hunt introduced species like feral cats and foxes. While they can take surprisingly large prey, often the young, small, or sickly individuals of larger species are preferred.
Scavenging and Opportunistic Foods
Wedge-tailed Eagles are significant scavengers, frequently consuming carrion. Roadkill represents a readily available food source. This opportunistic behavior contributes to their dietary flexibility and survival.
Reports of eagles preying on livestock, like lambs, often stem from observations of them scavenging deceased animals. Studies show lambs constitute a small percentage of their diet, with most instances involving eagles feeding on dead or dying stock. Dead or dying stock can account for up to 9% of their diet in areas with widespread sheep grazing. They also consume afterbirth. This scavenging role helps maintain environmental hygiene by clearing carcasses.
Hunting Techniques
Wedge-tailed Eagles use diverse strategies to acquire food. They often hunt by soaring at high altitudes, spotting prey from great distances with exceptional eyesight. Their vision allows them to accurately assess distances and pinpoint targets, similar to a camera’s zoom lens. They also use a “wait and hunt” approach, perching on trees or rocky outcrops and swooping down when prey comes within reach.
Cooperative hunting is effective, especially for larger animals like kangaroos. Pairs or small groups work together to flush out or corner prey, increasing their success rate. Powerful talons snatch prey from the ground or tree canopies, and hooked beaks efficiently tear food. Occasionally, they may even catch prey in flight.
Factors Influencing Diet
The Wedge-tailed Eagle’s diet is dynamic, influenced by environmental and biological factors. Geographical location and prey availability play a significant role. For example, in regions where rabbits are scarce, eagles may rely more on native marsupials like macropods. Disease introduction, such as calicivirus affecting rabbit populations, also prompts eagles to adapt their diets by consuming more native species.
Seasonal variations also impact food availability, shifting what eagles consume throughout the year. Eagle age influences dietary habits; younger, non-breeding birds might rely more heavily on carrion than breeding adults. Human activities, including agricultural practices and land use changes, can also indirectly alter prey distribution and abundance, affecting foraging choices.