Temperate Grassland Ecosystems
Temperate grasslands are also known as prairie, puszta, pampas,
plains or steppes with warm, moist summers (average 18ºC) and cool, dry winters (average 10ºC). It can snow during
the winter. The most prominent temperate grasslands are found in the Great Plains of Canada and the United States,
Argentina, South Africa, Central Eurasia and Australia.
There are two distinctive types of temperate grasslands – tall-grass (more than 2
meters) and short-grass less than 60 cm). Trees are generally not found in these regions due to the lack of
moisture and their need for a relatively longer life cycle. Grasses such as purple needlegrass, blue grama, buffalo
grass and galleta grow in the temperate grasslands.
Much of the temperate
grasslands in North America have been converted into farmland and the once teeming herds of bison and pronghorn
antelope have dwindled almost to extinction, except in regions where the prairie grasses have been retained. For
example in Southern Saskatchewan province it is still possible to see wild pronghorn, and buffalo have been
reintroduced into Grasslands National Park, the newest Canadian park located near Val Marie.
Steppes can be found in both Europe and North America where there are hot summers
and cold winters, with an average rainfall of 25 – 50 cm. All too frequently the local peoples grow crops such as
wheat and allow their livestock to graze, thus destroying the natural grasses.
Animal Adaptations
The most predominant species found in the temperate grasslands are large
grass-eating (herbivorous) ungulates (hoofed mammals), who are able to take full advantage of the various grasses
found there and who have a specially adaptive digestive system to process the grasses. Because of the relatively
short height of plants, they are able to see a predator from a distance and have adapted to be able to run swiftly
away from danger.
Examples of animals that can be found in temperate grasslands of North America
include bison, pronghorn antelope, rodents, badgers, coyotes, blackbirds, grouses, quails, hawks, owls, snakes,
grasshoppers, leafhoppers and spiders.
The Russian steppes are home to tarpan (wild horse), saiga antelope, polecats and
mole rats, amongst others. The latter animal lives underground in burrows and is adapted to this lifestyle by
virtue of their short limbs, small eyes, tiny external ears and large incisors used for digging.
Many grassland mammals have front legs and paws adapted to dig burrows where they
can be safe from predators.
Many prairie animals have coats that blend in with the surrounding vegetation, so
that they are camouflaged from predators. In the colder climates of Eurasia, the snow leopard has a coat of creamy
white behind dark rosettes which helps to camouflage them in the snow and rocks.
Aardvarks eat only insects, utilizing their large claws to dig into anthills and
termite mounds, and then utilizing their long, sticky tongues to lap up the insects.
Prairie dogs mostly eat grasses, seeds, leaves, flowers and fruit (herbivorous),
but also eggs and insects.
Animals such as red-tailed hawks, owls, skunks, coyotes and opossums are carnivores
(meat-eaters) and feast on small mammals.
Badgers are an example of an animal that eats both animals and plants (omnivores),
choosing from a variety of rodents, frogs, snakes, insects, fruits and roots.
The Australian dingo (wild dog) is an example of an animal that is active at night
(nocturnal)
Despite many efforts to eradicate the black-tailed prairie dog because they were
considered a nuisance to farmers, they still manage to survive in certain areas, living in burrows adjacent to one
another in great numbers. These are known as "towns". The highly endangered black-footed ferret depends upon the
prairie dog as its sole source of food and, thanks to the efforts of several conservation groups, are now making a
comeback in Wyoming and will soon be re-introduced into Grasslands National Park in Saskatchewan, Canada as the
population of black tailed prairie dogs becomes stable.
Another example of interdependence is the monarch butterfly and the milkweed plant.
The butterfly larvae eat the milkweed leaves (toxic to most other insects). This toxin accumulates in the
butterfly’s body, making it inedible to most birds, and who consequently avoid the monarch.
As the weather turns cold, animals such as the thirteen-lined ground squirrel digs
a deep nest below the frost line, plug the entrance with soil to keep themselves warm. In addition, these squirrels
also build two other kinds of burrows – one for hiding for short periods of time and another to nest in during the
warmer weather.
Plant Adaptations
The soil of the grasslands is generally deep and fertile, with roots penetrating
way below ground where moisture is retained during droughts.
Perennial grasses bud below ground or just at the surface, making them resistant to
drought, fire and cold. The stem is narrow and upright, reducing the affects of heat in the summer.
As with the tropical grasslands, the temperate grasslands also rely on seasonal
drought, fire and grazing to prevent shrubs and trees from becoming established. Many beautiful wildflowers such as
asters, coneflowers, goldenrods, sunflowers, clover, etc. thrive in these regions, as well as certain trees such as
willow, oak and cottonwood near the rivers. Insects are attracted to the colourful blossoms of the wildflowers; as
the insect feeds, the pollen brushes off on the insect who then carries it to another plant and in the process
fertilizes that plant.
The stinging nettle plant has a beautiful plant but contains a painful sting to
protect itself from humans and grazing animals.
Overgrazing and plowing over of grasslands lead to erosion of the soil during
droughts. The loose soil left behind is picked up by strong winds, causing dust storms for miles and the loss of
fertility in the earth.
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