Ecosystem engineers are perhaps one of nature’s biggest problem solvers. They can alter their surroundings differently, affecting countless other species. Without them, we probably wouldn’t have the landscapes and environments supporting varying life forms. Here, we look at what ecosystem engineers are, who they are, and their impact on the ecosystem.
What Are Ecosystem Engineers?
The most agreed upon ecosystem engineer definition is any species capable of creating, maintaining, destroying, or significantly modifying a habitat. Because they can have a telling impact on species richness and landscape level heterogeneity of an area, ecosystem engineers are vital for maintaining the health and stability of the places they thrive.
Keystone Species vs Ecosystem Engineers
The battle between keystone species vs ecosystem engineers is usually a close one, considering the concepts often overlap. However, the two are different. Ecosystem engineers directly affect the environment where they thrive. For instance, beavers (a great example of an ecosystem engineer) build dams, creating ponds that support aquatic ecosystems.
On the other hand, keystone species rely on their abundance to cause a ripple effect that then affects the ecosystem. For example, wolves control prey populations that, in turn, prevent overgrazing. Wiping out the wolves would result in overpopulation of prey, leading to overgrazing. In this case, the population of wolves is big enough for their absence to affect the ecosystem.
Examples of Ecosystem Engineers
To further understand ecosystem engineers and their roles, here are some prominent examples and what they do:
Beavers
Beavers are the perfect representation of what ecosystem engineers really are. They are semiaquatic rodents native to the Northern Hemisphere. The creatures are among the biggest from the rodent family, only trailing to capybaras. Adult beavers can weigh up to 50 kilograms (110 pounds).
The animals thrive in areas with rivers, streams, and wetlands. Their engineering impact comes from the fact that they can build dams using branches, rocks, and mud. This creates ponds and wetlands that support other diverse species, including amphibians, fish, and waterfowl. Additionally, by slowing down water flow, beavers help reduce soil erosion and improve water quality.
Coral Polyps
From Class Anthozoa, you can find coral polyps in shallow, warm marine waters. They are tiny, soft-bodied organisms related to jellyfish and sea anemones. As for engineering impact, coral polyps secrete calcium carbonate, forming reefs’ hard structures. The reefs provide shelter, breeding sites, and feeding grounds for many marine species.
Besides being critical for the survival of many fish and invertebrates, coral reefs shield coastlines by slowing down wave energy.
Prairie Dogs
Prairie dogs are herbivorous, burrowing ground squirrels with five recognized species. As ecosystem engineers, these animals dig complex burrow systems, aerating the soil and improving water infiltration.
The burrows created by prairie dogs are often used as shelter by other animals, including black-footed ferrets, snakes, and burrowing owls. Also, by facilitating the thriving of grasslands, prairie dogs support plant diversity and grazing species, including bison.
Earthworms
Earthworms are among the most famous soil-dwelling terrestrial invertebrates. They have other slang names, including rainworm, angleworm, nightcrawler, and dew-worm. You can find earthworms in agricultural fields, soil in forests, and grasslands.
There, they burrow through the soil, creating channels for air and water to pass through. The organisms also help decompose organic matter, enriching the soil with much-needed nutrients.
Elephants
Famous for their massive bodies, elephants are the largest living land animals. They have elongated tusks (basically their incisor teeth), which they use to move objects and as weapons. Scientists classify elephants as ecosystem engineers because they uproot trees and trample vegetation, shaping open grasslands.
Additionally, when elephants dig the ground during dry seasons, they create waterholes that help other species hydrate. Elephants’ dung can also disperse seeds, ensuring that plant reproduction continues. The iconic animals help maintain grassland and forest ecosystems, benefiting other creatures.
Termites
Termites are insects that eat decaying plant material. This can be wood, soil humus, or leaf litter. As such, termites are common in tropical and subtropical regions.
The insects are famous for their mound-making abilities. By doing so, termites help regulate humidity and temperature. If you couple that with the fact that they can create tunnels to help aerate the soil and improve nutrient cycling, termites are perfect ecosystem engineers.
Kelp
While kelp may appear as plants, they are not! They are large brown algae from the order Lanibariales. To qualify as ecosystem engineers, kelp usually form dense “underwater forests,” which other marine organisms call home. Looking at the bigger picture, these “forests” also help reduce wave energy, protecting coastlines from erosion.
Woodpeckers
As the name suggests, woodpeckers are birds famous for their wood-pecking abilities. They can be found worldwide, excluding Madagascar, Australia, New Guinea, New Zealand, and other extreme polar regions.
As woodpeckers remove tree cavities for nesting, the spaces left behind can be homes for other animals, including squirrels, bats, and owls. That’s how they qualify as ecosystem engineers.
Gopher Tortoises
Gopher tortoises are mainly found in the sandy soils of the southern United States. They are seen as ecosystem engineers because they dig huge burrows, protecting them from predators and extreme weather. According to extensive research, these burrows are also home to more than 350 other species, including frogs and snakes.
The Impact of Ecosystem Engineers’ Absence to the Ecosystem
After learning about how ecosystem engineers operate, what do you reckon would happen if they weren’t there anymore? Since many other species depend on them, eliminating ecosystem engineers from the ecosystem would mean the other reliant animals would disappear with them.
Without shelter, nesting grounds, and spaces to evade predators, the reliant animals would be extinct in no time. Other probable effects include a decline in biodiversity, altered ecosystem functions, food web disruptions, and increased vulnerability to environmental change.
Rather than imagining what would happen if ecosystem engineers are removed from the ecosystem, there is already a case in point. In the 20th century, the wolves in Yellowstone National Park went extinct. This led to an overpopulation of elk and overgrazing. The authorities had to re-introduce more wolves to Yellowstone National Park to stabilize the elk population.
