The Grassland Ecosystem
Cara Vasso and Phoebe Alley
What are Grassland Ecosystems?
Grassland ecosystems are open areas of habitat that are mainly composed of grasses and grasslike plant species, such as wild oats, foxtail, purple coneflowers, buffalo grass, goldenrod, and sunflowers. Other forms of vegetation are not suited to survive in the dry environment of grasslands and thus are rarely seen in these ecosystems. Summers in grasslands are very hot and may reach 45°C (113°F). Winter temperatures often fall below freezing, which is 0°C (32°F). In addition to the name “grassland”, this type of terrain can also be called a savannah, prairie, or a rangeland. Grassland ecosystems can be located in South Africa, Hungary, Argentina, Uruguay, Russia, and the plains of central North America. They are most often located between forests and deserts. The commonality between areas deemed as grasslands is their hot summer temperatures and low precipitation, as well as a lack of trees. The soil found here is deep, dark, and very fertile. Because water is scarce, grassland ecosystems are particularly fragile and depend on regular fires to help maintain the ecosystems’ health and vigor. The presence of burns has several purposes in a grassland ecosystem- it warms up the soil, reduces the lead litter that accumulates each year, and allows sunlight to penetrate the soil. Roughly 80% of global fires occur in grasslands each year.
Animals in Grassland Ecosystems
Because grasslands have such a unique and diverse climate, they are host to a diverse collection of species, providing a home to some of the most strange and distinct animals. The majority of species are grazing animals, meaning they require a large amount of space and territory to hunt, breed, and eat. Some of the species that have adapted to living in this type of ecosystem include buffalo, rhino, elephants, zebra, antelope, badgers, armadillos, and many different kinds of insects. The animals that do not graze for their food source, such as wolves, coyotes, swift foxes, leopards, hyenas, and badgers, are grassland predators, feeding on small animals like mice, molerats, and squirrels. In addition to the grazing mammals and predators, grasslands are home to numerous birds of prey such as red-tailed hawks, american kestrels, short-eared owls, barn owls, Savannah sparrows and Henslow’s sparrows.
Issues with the Ecosystem
Most issues relating to grasslands revolve around habitat loss. Habitat loss in the grasslands is mostly driven by human actions. Agriculture is a leading threat of habitat loss. Around the world, around 50% of temperate grasslands and 16% of tropical grasslands have been transformed for agricultural purposes. For example, 42% of the grasslands in the Northern Great Plains have been converted into fields of crops. The Northern Great Plains is located in the United States, and is one of the four remaining temperate grasslands in the entire world. Five percent of the Northern Great Plains has been developed by humans, which leaves only 53% of the ecosystem undamaged. One way that agriculture is harmful is due to the use of toxic pesticides. Pesticides are extremely harmful to the native flora and fauna. Another way that agriculture is damaging is by degrading the soil. Soil is an incredibly underrated component of ecosystems, and it is truly the foundation of healthy vegetation. Grasslands rely on healthy soil for adequate flora and fauna vegetation. Agricultural practices often incorporate only using one type of crop at a time, instead of a variety of crops, which depletes nutrients in the soil and reduces biodiversity.
Another threat to grasslands that results in habitat loss is the expansion of urban areas. Grasslands typically contain level grounds, which makes them desirable to develop. Urbanization of the grasslands, let alone any habitat, completely transforms it. Not only will the flora and fauna in the areas being directly developed be disturbed, but the surrounding areas will also as the biome changes. In addition to habitat loss, grasslands also face threats from climate change. Climate change causes droughts, abnormal participation patterns, and increased temperatures. These effects are harmful to vegetation because they don’t allow for proper growth conditions. Increased temperatures will most likely cause an increase in wildfires, especially since grasslands are found in already dry climates. In severe cases, grassland habitats could transform into deserts. Hunting is another threat to grasslands. Many animals in the grasslands are poached, which disrupts the natural flow of the biome. The plants and cycles within an ecosystem are just as dependent on the animals that live in it.
Policies Addressing the Issues
There are multiple policy initiatives surrounding the grasslands. An example of a global-scale policy initiative is the integrated approach between the International Union for Conservation of Nature (IUCN), the World Commission on Protected Areas (WCPA), and the Temperate Grasslands Specialist Group. The Temperate Grasslands Specialist Group, with the support of the IUCN and the WCPA, has implemented the Temperate Grasslands Conservation Initiative (TGCI). The goal of the TGCI is to preserve the grasslands on a global scale. Since the plan focuses on conservation at a global scale, it is seeking to provide spatial equity across habitats. Most of the plan revolves around land management conservation and sustainability. Some of the goals of the plan incorporate sustainable development, protection of both private and public land from disturbances, and encouraging communication between indigenous people and governments. It is important that the plan acknowledges and incorporates indigineous people into the conversation when planning their goals. Indigineous people rely on the grasslands for life and cultural survival, and should therefore have a role in creating the plan. The TGCI strives to provide legal protections ranging from untouched grasslands to grasslands that have already been severely damaged and fragmented. It is important and beneficial to the habitat as a whole that the plan doesn’t neglect areas that are already damaged. The plan originally hoped to double the protection of the grasslands, and has made impressive strides since its launch. The TGCI is an ongoing process, and is far from being achieved.
An example of a smaller scale policy initiative is the Grassland Ecosystem Management Plan, which was proposed by the city of Boulder, Colorado. Around 24,000 acres within the Grassland Management Plan is managed by Boulder’s “Open Space and Mountain Parks” sector. The management goal of this area is to protect and conserve the species within it. The strategy of the Grassland Ecosystem Management plan is to incorporate an integrated approach between biologists, government entities, ecologists, and other beneficial people in order to come up with long-term conservation targets. These targets seek to enhance and maintain the overall biodiversity of the grasslands. The Grassland Ecosystem Management also strives to discover and implement sustainable agricultural practices. Sustainable agriculture is integral to the wellbeing of the grasslands as harmful agricultural practices are a leading cause of habitat loss in these areas.
Other than local and global initiatives, continent-wide approaches are utilized as well. In Australia, the Native Grassland Conservation Strategy is a good example. The goal of this strategy is to build off of the successes of previous policies that have conserved large portions of grassland habitat. It is considered to be a territory-wide approach that encompasses all types of grasslands including rocky and mountainous. It also encompasses grasslands that have already been disturbed. Most importantly, the plan acknowledges the changing climate, and it seeks conservation management based off of those unprecedented changes. This is important because a “business as usual” approach does not apply to any habitats around the world, as their biome is changing under the disturbances of global warming. Similar to the Temperate Grasslands Conservation Initiative, the Native Grassland Conservation Strategy acknowledges indigenous people, in this case the Ngunnawal people, as the “traditional custodians” of the territory.
How Animals are Affected
Animals are affected by nearly all of the changes grasslands are undergoing. Habitat loss has a direct negative effect on animals, but even habitat alteration can have severe consequences. This is because not all animals will have the resources to adapt to the sudden changes within their niche. Hunting is another factor that has decimated species.The species within the grasslands exist in an interconnected web, with many species relying on each other for survival. Therefore, when one animal becomes threatened or extinct, it can have dire consequences for the rest of the ecosystem. One example of an animal that has declined severely in numbers is the prairie dog. Prairie dogs have declined by around 95% of their original population, mainly due to habitat loss and hunting. Prairie dogs are considered “key species” within the grasslands, meaning they have a large effect on the environment. Specifically, prairie dogs have 9 other species relying on them for survival. Not only are they important for sustaining other animals, but key species also influence soil and plant life. For example, prairie dogs improve vegetation and enrich soil in the grasslands. This happens when their burrows imitate aquifers, which prevents water from eroding land as well as cooling it. Prairie dogs are just one example of many key species within the grasslands that are vulnerable to climatic and human disturbances. Another key species in grassland ecosystems is the bison. Millions of bison previously roamed the grasslands, but their numbers have declined significantly. Today, it is estimated that around 350,000 bison exist in North America. However, when Columbus came to America there were around 30 million. Similar to prairie dogs, over-hunting and habitat loss are leading causes for the decline of bison.
What You Can Do to Support Grasslands
Temperate Grasslands have served as a primary habitat for people, animals, and plants over the centuries. The unique, dry, grassy plains have supported large numbers of grazing animals, many of which are nearing extinction today due to overfarming, overhunting, and climate change. While this is a depressing fact, there are things you can do as a consumer and animal-lover to support the well-being of this vital ecosystem.
- Shop local! By choosing to buy food that is locally grown, you are not supporting corporations that may be overplowing grasslands and converting them into cropland. If you are going to buy non-local food, do your research about the sustainability of the corporation and the cropland they are using.
- Educate yourself on the type of laws that your local or federal government is enacting concerning agricultural development, particularly the USDA and the U.S. Fish and Wildlife Service. Read the fine print and write/call your representatives if you’re concerned about what you see.
- Advocate for the preservation and protection of grasslands through donations of time and money to organizations that are working to save grasslands. Some organizations that are doing incredible work to conserve grassland habitats include:
- Ducks Unlimited: Organization committed to conserving wetlands and valuable habitat in priority areas for North American waterfowl. The work that Ducks Unlimited does regarding grasslands helps to secure and restore the habitat to reduce predation rates and improve nest success.
- The Nature Conservancy: Extremely reputable organization who are known for collaborating with policy-makers and industry leaders to minimize the impacts of development and maintain the health of American prairies.
- Defenders of Wildlife: Animal-focused organization that identifies emerging conservation challenges and works tirelessly in courts and on Capitol Hill to defend wildlife species and habitat.
- Advocate for healthier alternatives to pesticide use in agriculture. Industrial monoculture farming is resource intensive and depends on heavy pesticide use to keep up with the demand for the products. These toxic pesticides seep into the soil and into the Earth that the animals of the grasslands depend on. Many are poisoned and species are driven to local extinction as a result. There are many more sustainable approaches to monoculture farming that can be advocated for, such as crop rotation, using cover crops, and increasing soil fertility. Do your part by avoiding produce that is genetically engineered with pesticide use and speak out about the dangers of pesticides.
- Plan a trip to a grassland near you! See for yourself the wonders of these incredible habitats. Grassland habitats, or prairies as they are called in North America, are located in a lower belt of midwestern America. Always be respectful of the place you are visiting and ensure that you are caring for the space.
Sources: City of Boulder Colorado, The Government of the Australian Capital Territory, Humane Society, International Union for Conservation of Nature, Jungle Jenny, National Geographic, The Nature Conservancy, Pets on Mom, Sciencing, World Wildlife Foundation