The echidna, a spiny mammal native to Australia and New Guinea, is one of the world’s most unique creatures, belonging to the group of egg-laying mammals known as monotremes. Its diet is highly specialized, and the animal’s entire anatomy, from its snout to its tongue, is perfectly engineered for finding and consuming a specific type of prey.
The Primary Diet: Ants and Termites
The diet of the most widespread species, the Short-beaked Echidna (Tachyglossus aculeatus), centers heavily on myrmecophagy, which is the consumption of ants and termites. These insects are hunted with a keen sense of smell, which the echidna uses to locate colonies within the ground, under leaf litter, or inside rotting logs. The echidna is an opportunistic insectivore, but these two groups of social insects constitute the bulk of its nutritional intake across most of its extensive range.
The echidna does not simply consume the adult insects but often targets the eggs, larvae, and pupae, which are richer in nutrients and softer to digest. In certain habitats, particularly arid and semi-arid zones, termites are the dominant food source, while in cooler, wetter areas, ants are more prevalent. However, the echidna’s diet shows some flexibility; for instance, in parts of Tasmania where termites are absent, the echidna compensates by consuming large quantities of scarab beetle larvae.
An echidna must consume a significant volume of insects daily to meet its energy requirements. The insects are typically ingested whole, along with a considerable amount of soil and debris from the nest itself. This high-volume consumption of small, protein-rich prey necessitates a continuous foraging behavior, which the animal undertakes during the cooler parts of the day.
Specialized Feeding Mechanics
The echidna possesses remarkable physical adaptations that allow it to exploit its insect diet without needing teeth. It has a long, slender snout, often referred to as a beak, which is used to probe into crevices and ant or termite mounds. This snout is equipped with electroreceptors and a strong sense of smell, which together help the animal locate the electrical signals and chemical trails of its prey underground.
The tongue is the most specialized feeding tool, being long, slender, and coated in sticky saliva produced by large salivary glands. The tongue can be rapidly protruded and retracted, which is how the echidna can collect dozens of small insects in a matter of seconds. For the Short-beaked Echidna, the tongue can extend up to 17 centimeters and effectively “slurps” up the prey.
Since the echidna lacks teeth, the captured insects are ground down using a unique mechanism within the mouth. Hard, keratinous pads at the back of the mouth press the food against corresponding ridges on the roof of the palate, effectively crushing the exoskeletons for proper digestion. Powerful, shovel-like claws on the forelimbs are used to tear open termite mounds, logs, and soil to gain access to the insect colonies.
Dietary Differences Across Species and Development
The four species of echidna exhibit notable differences in their dietary focus, primarily distinguished by the length of their snouts. The Short-beaked Echidna, with its shorter snout, largely focuses on the smaller prey found in nests, such as ants and termites. In contrast, the three species of Long-beaked Echidnas (Zaglossus spp.), which are restricted to New Guinea, have a longer, more downward-curving snout that is better suited for probing deeper into the soil.
The Long-beaked Echidnas mostly consume larger soil invertebrates, such as earthworms, beetle larvae, and other arthropods, rather than specializing in ants and termites. Their tongues are also structured differently, featuring tiny, backward-pointing spines that help them hook and secure the slippery earthworms. This anatomical difference reflects a clear divergence in foraging strategy and preferred prey type between the two main groups.
The youngest echidnas, called puggles, have a completely different diet during their early development. After hatching from an egg, the puggle is nourished exclusively by its mother’s milk within a temporary pouch. Unlike most mammals, the mother echidna does not have nipples; instead, the milk is secreted through specialized pores located on milk patches on her abdomen. The puggle laps up this milk directly from the skin surface, remaining in the pouch until it begins to develop spines, typically around two to three months of age. Weaning is a gradual process, with the puggle transitioning to an adult insectivore diet over several months after being moved to a nursery burrow.