Keystone species examples include: Beavers, Sea Otters, Prairie Dogs, Hummingbirds, Bees, African Elephants, Tiger Sharks, star fish, desert tortoises among others.
These are organisms that hold together an ecosystem and are classified into four main categories: (i) predators (ii) prey (iii) ecosystem engineers and (iv) mutualists.
- Predators are essentially the ‘controllers’ of the population of prey species. This control ensures that the quantity of plants and animals is sufficient throughout the food web.
- Prey serves as a critical source of food for predator species. They range from the Antarctic krill to Canadian snowshoe hares.
- The ecosystem engineers are those that can change, create or destroy a habitat like the beaver.
- Mutualists on the other hand are two or more species within an ecosystem that benefit from each other such as the bee and flower ‘relationship’.
Keep on reading to learn more about these keystone species and the important role they play in the ecosystem.
16 Keystone Species Examples
1. Beavers
Beavers prefer freshwater ecosystems. Water is an important part of their habitat as they like to swim, dive and float logs. They like to build dams as lodge entrance protection from potential enemies on land.
While building these dams, they create a wetland habitat in which many more other organisms can live. By taking down dead and old trees along riverbanks, they allow for newer and healthier trees to thrive and as a result, play a significant role in maintaining and sustaining the ecosystem. [1]
Beavers are often referred to as wetland engineers because of their ability to maintain wetland ecosystems which in turn purifies water, increases biodiversity and prevents large-scale flooding.
2. Sea Otters
Sea otters live in coastal marine habitats, rocky shores, sandy sea bottoms and coastal wetlands in general. They like offshore areas where there is an abundance of food and kelp canopy.
Sea otters maintain the ecosystem through their predatory nature. They prey on sea urchins and thus reduce their population hence allowing kelp canopies to flourish. Similarly, they feed on other nearshore species such as clams and consequently preserve the nearshore ecosystem.
3. Prairie Dog
The Prairie dog is an example of a keystone species whose large population has a positive impact on the ecosystem.
They are a food source for animals such as hawks and foxes. [2]
Their burrows are used by black-footed ferrets as homes. Furthermore, prairie dogs help in the aeration and fertilization of the soil thus enabling different types of plants to thrive.
4. Bees
“If the bee disappears from the surface of the Earth, man would have no more than four years to live,”
Albert Einstein
Albert’s words could not be far from the truth, his statement is indeed a true reflection of the significance of bees within their ecosystem.
Bees are mutualistic keystone species in that while they acquire nectar from flowers, they also aid in pollinating the flowers and as a result, contribute to the survival and blossoming of flowers.
Plant populations continue to thrive, thanks to the symbiotic relationship between them and bees. This further sustains the ecosystem as more species rely on plants for food.
Beyond being pollinators, bees are also efficient in zootherapy. They store antimicrobial molecules in honey and other non-edible substances that they produce which have medicinal properties significant to humans and other organisms within their ecosystem.
5. Hummingbirds
Hummingbirds are another example of a keystone species. They mostly inhabit temperate woodlands, cloud forests, tropical forests, mountain meadows and deserts. Their habitats are characterized by numerous flowers and thus can be found in urban and suburban gardens as well.
They are keystone mutualists as they are pollinators and aid many plants to reproduce.
6. The African Elephant
African elephants are ecosystem engineers as well as keystone mutualists. They shape their habitat in several significant ways. For example, their dung consists of seeds which are significant in spreading plants across the ecosystem. On top of that, the dung also provides a home for dung beetles.
7. Tiger Sharks
Tiger Sharks are keystone species because they are apex predators and strike a balance in their food webs thus maintaining the ecosystem.
They prey on sea turtles who feed on seagrass. Seagrass beds are known to be the protective habitats for fish and shellfish. Therefore, by reducing the population of the sea turtles they preserve the seagrass beds and in turn fish. [3]
Tiger sharks live in tropical waters and are common throughout the world’s temperate waters save for the Mediterranean Sea. Both open oceans and shallow coastal waters make for their homes.
8. Grizzly Bears
Grizzly bears are both predatory and keystone mutualists in that they regulate healthy populations of their prey such as elks and help in dispersing seeds of plants they feed on through their waste.
These animals prefer woodlands, forests, prairies and alpine meadows. Within their habitats, they prefer riparian areas along the rivers and streams.
9. Star Fish
All the oceans across the world are home to starfish. They like tropical coral reefs, rocky shores, seagrass meadows and deep-sea floors.
They are predators and help to keep the populations of sea creatures such as mussels under control. This in turn regulates the healthy population of seaweeds and sea creatures such as sea urchins that feed on them.
11. Gray Wolves
The gray wolf plays a critical role within its ecosystem by regulating healthy prey populations. In doing so, they also enable other plant and animal species to thrive. Generally, they help maintain the food web.
These animals thrive in woodlands, forests, deserts and grasslands. They are predatory carnivores and like to feed on deers and elks among other large hoofed mammals.
Related: Did you know the gray wolf is a type of wild dog?
12. Desert Tortoises
Desert tortoises are found on bajadas, alluvial fans and bajadas. They enjoy burrowing into the soils thus their habitats will not only be defined by the plants present but also the soils available.
They are considered ecosystem engineers as other species within the ecosystem benefit greatly from their burrows. Such species include the Gila monsters, roadrunners and peccaries.
13. Jaguar
Within their ecosystem, Jaguars are apex predators whose main role is to regulate the healthy prey populations by keeping them at a balanced level.
They are the largest cats in the Americas and are found in dry deciduous forests, rainforests and tropical forests.
14. American Alligator
American alligators thrive in subtropical and tropical ecosystems such as cypress swamps and marshes. They are common in southern Texas and South Carolina.
They are apex predators and are important in their native ecosystems as they help to regulate healthy prey populations. Moreover, they are also ecosystem engineers.
These Alligators use their tails to dig burrows in the mud which they use for nesting and keeping warm. When they abandon these holes, freshwater fills them and are used by other species as a source of drinking water or breeding grounds.
15. Sea Urchins
Sea urchins are a keystone prey species. They are a source of food for a wide variety of predators such as sea otters and starfish. In addition, they help to maintain a balance between coral and algae.
Sea Urchins live in oceans and cannot survive in freshwater habitats. They are mostly found in rocky reefs on the seafloors within kelp forest ecosystems. Kelp comprises a large part of their diet.
16. Snowshoe Hare
The snowshoe hare is found in boreal forests in North America. They are important prey species as they are a source of food for a wide variety of predators.
They are a keystone prey species as they are food for predators such as foxes, coyotes, hawks and many other predators within their native ecosystem. Moreover, their herbivorous nature allows them to regulate the population of the plant species within their ecosystem.
Keystone Species Examples Summary
| Keystone Species Examples |
|---|
| Beavers |
| Sea Otters |
| Prairie Dogs |
| Bees |
| Hummingbirds |
| African Elephants |
| Tiger Sharks |
| Grizzly Bears |
| Star Fish |
| Gray Wolves |
| Desert Tortoise |
| Jaguar |
| American Alligator |
| Sea Urchins |
| Snowshoe Hare |
