What are Some Burrowing Animals?

Many burrowing animals have existed, including numerous mammals, insects, amphibians, reptiles (including small dinosaurs), crustaceans, worms, and even a few fish and birds. The start of the modern era of life, the Phanerozoic, is defined by the appearance of complex burrows in the fossil record 542 million years ago. These burrowing animals broke up the previously hard-packed and anoxic ocean floor, allowing much greater biological diversity as well as interspecies competition. Burrowing is thought to have evolved as a defense against predation. Many ecological arms races between predators and prey can be characterized as burrowing animals versus predators trying to get animals out of their burrows.

The most famous burrowing animals are mammals, including rabbits, chipmunks, moles, gophers, and groundhogs. The burrow of a single groundhog occupies 1 cubic meter, while the complex warrens of rabbits may occupy hundreds of cubic meters. Some animals, such as the marsupial mole, have adapted so extensively to burrowing that they have lost their eyes and hunt prey using only their senses of smell and touch. In Australia, burrowing rabbits were introduced in the late 18th century and have since reproduced to be out of control, destroying large tracts of the bush and leading to the extinction of many other species.

Though we are most familiar with mammalian burrowing animals, non-mammalian burrowers are also common, especially in the sea. Entire animal phyla, such as phoronids and mud dragons, spend their life in self-constructed burrows, living entirely using tiny cilia that reach out into the water. Some sea animals can secrete special chemicals that allow them to burrow directly into hard rock, albeit at a slow rate. Some of the most prolific burrowers in the sea are the polychaete worms, aquatic annelids that are expert bottom-scavengers. These burrows help them escape the jaws of bottom-dwelling predatory fish.

Some burrowers that evolved from surface animals have developed highly unusual adaptations to the dark, subterranean life. One animal, the star-nosed mole, has a sense organ composed of incredibly sensitive nasal tentacles called Eimer's organs. These are used by the mole to detect very small prey animals. The star-nosed mole is also known as nature's fastest eater, taking as little as 120 milliseconds (faster than the human eye can follow) to identify and consume prey items.

A burrowing animal is one that digs into the ground to create a space for living, protection, or hunting. These animals have specialized behaviors and physical adaptations, such as strong limbs, claws, or snouts, which enable them to move soil efficiently. Burrowing is common among mammals, insects, reptiles, and even some fish species.

Animals burrow for various reasons, including seeking refuge from predators, creating a stable environment for raising young, storing food, or escaping extreme weather conditions. For instance, according to the National Wildlife Federation, groundhogs hibernate in burrows to survive the winter, while burrows can also help animals like desert tortoises regulate their body temperature in harsh climates.

Some animals, like the prairie dog, are renowned for their intricate burrow systems. Prairie dog towns can span hundreds of acres with a network of interconnected tunnels and multiple entrances. Similarly, rabbits construct warrens with specialized chambers for nesting and escape routes, showcasing a sophisticated understanding of spatial design and social living.

Yes, several aquatic animals are adept burrowers. For example, the fiddler crab excavates burrows in mudflats and marshes, which serve as protection against predators and extreme temperatures. Additionally, some fish, like the lungfish, burrow into the mud during dry seasons to survive periods of drought, encasing themselves in a mucus cocoon, as reported by the American Society of Ichthyologists and Herpetologists.

Burrowing animals play a crucial role in their ecosystems. Their digging activities aerate the soil, improving its fertility and water infiltration. They also contribute to seed dispersal and the cycling of nutrients. According to a study by the University of Oxford, earthworms, often called 'ecosystem engineers,' can move large amounts of soil, influencing soil structure and nutrient dynamics.

Yes, many burrowing animals have adapted to urban environments. For instance, foxes have been known to dig dens in city gardens, while rodents like rats and moles can be found burrowing in urban parks and yards. These animals often seek out spaces that provide shelter and food resources, even in the midst of human development.