Key
Points
Key Points will give you the main information you
should know to teach the activity.
- An
animal needs air, food, water, shelter and space to
survive. An animal's habitat is the place where it
can find these things it needs to live.
- Animals
need air because oxygen is necessary in animals' bodies
for the chemical process that allows usable energy
to be released from food.
- Animals
need food because it provides energy and nutrients
necessary to the body to perform life functions.
- Animals
need water because it transports nutrients and wastes
in the body, it regulates body temperature and it
is necessary as an ingredient in internal chemical
reactions.
- Animals
need shelter because it protects them from the elements
and from predators.
- Animals
need space because overcrowded areas lead to starvation
and disease.
- For
concise information on spotted salamanders, river
otters, American alligators and bottlenose dolphins,
scroll down to "Featured Species" section.
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Detailed
Information
Detailed Information gives more in-depth background
to increase your own knowledge, in case you want to
expand upon the activity or you are asked detailed questions
by students.
Animals
need food, water, air, shelter and space to survive. No
matter where an animal lives, it must be able to attain
these things. The world is comprised of many different environments
with many varied climates. Because of this, animals develop
specialized adaptations to allow them to get the things
they need to survive from a variety of different environments.
Where they get these things is there habitat. The animals
found in the deep ocean are not the animals found in the
tropical rainforest or the desert or the tundra, yet all
these share in common the need for food, water, air, shelter
and space.
Animals
cannot produce their own energy like plants can, and
so they must eat other organisms to get their food energy.
Some animals, such as deer and elk, are herbivores,
and eat only plants. They make use of the energy the
plant has produced through photosynthesis. Some animals,
such as eagles and hawks, are carnivores that eat other
animals and get their energy from the organic compounds
stored in their prey. Some animals, such as humans,
are omnivores that can eat both plants and animals.
Some animals are scavengers that live off of dead animals,
such as turkey vultures, and get energy from the organic
compounds remaining in the animal’s dead carcass. Some
animals, such as blue crabs, are opportunistic feeders,
meaning they will eat just about anything they can get
their mouths around. All animals depend on the food
they eat to receive the energy and nutrients they need
to carry out their life functions.
All
living things depend on water to survive. Water is a
major component of all the fluids in the body as well
as the protoplasm of each individual cell. Water is
also important as a solvent for chemicals and nutrients
in the body. Water makes up 60 to 90% of the composition
of all living things. For this reason, all animals must
find a way to intake water on a regular basis.
All
animals must bring oxygen into their systems in order
to convert food energy into usable energy. For this
reason, all animals must utilize some form of respiration.
Terrestrial animals, such as reptiles and mammals can
pull oxygen out of the atmosphere. Aquatic animal such
as fish can pull oxygen out of the water. Amphibians
can do both. Because life processes occur twenty-four
hours a day and they all require energy, an animal would
soon die without oxygen.
Animals
also depend on shelter to survive. Shelter protects
an animal both from the elements and from predators,
and thus increases its survival chances. Shelter can
take many forms. The shells of snails and other mollusks,
the nests of birds and the burrows and dens of mammals
are just some examples of shelter.
Space is necessary
too. If too many animals are competing for the same space, than
they are also often competing for food, water and shelter. Being
crowded together makes the animals more prone to diseases and
parasites, which are spread more quickly and easily. Because an
environment can only support a certain number of organisms, removing
predators from an ecosystem can sometimes have negative effects
on the animals the predator preys on. Without the limiting factor
of predators, the prey animals can multiply rapidly causing a
loss of space for these animals and leading to diseased and malnourished
animals.
An animal's
habitat is the place where it can get air, food, water, space
and shelter. The animal's adaptations determine where its habitat
will be. Because an animal has specific habitat requirements,
if you take the animal away from its habitat, or if you bulldoze
the habitat away from the animal, the animal will not survive.
This is why a habitat that is suitable for one animal, such as
a house for a human, may not be suitable for another animal, such
as a house for a salamander. The house cannot meet the salamander's
habitat needs.
Top
Featured
Species
Spotted Salamander (Ambystoma maculatum)
The spotted salamander is the state amphibian of South Carolina.
This 6 to 10 inch salamander is found near shallow pools in
deciduous forests in eastern North America from Louisiana to
Canada as well as throughout South Carolina. In South Carolina
it is most common in the Piedmont and Mountain regions. These
salamanders avoid areas prone to flooding or pools populated
with fish. They spend a good deal of their time in burrows underground
or under trees and so are difficult to find.
Spotted
salamanders prey on insects, worms, slugs and other
small invertebrates. They can most easily be found on
a rainy night on the forest floor looking for food.
In the wild, they can live over 30 years.
Though
they spend most of their adult life on land, they lay their
eggs in water and spend their larval stages in water. Therefore,
spotted salamanders tend to stay near aquatic habitats.
When it warms in spring, the female will move to a shallow
pool, lay 200-250 eggs in a mass on submerged sticks. The
eggs will hatch within two months. The larval salamanders
will remain in the pool for another two months, maturing
and developing until they look like adult salamanders. They
then move on land to begin the terrestrial life of an adult
spotted salamander.
River
Otter (Lutra canadensis)
The
largest mammal predator in the mountain stream, river
otters are found throughout North America except for the
extreme northern portion of Alaska and the Southwest desert and
arid Plains states. Locally common in South Carolina, it ranges
across the state in virtually all freshwater and estuarine aquatic
habitats. A member of the weasel family, the otter has short legs
with webbed toes, a broad tail, and an elongated body. An adult
otter will grow from three-and-half to four feet in length and weigh
from ten to twenty-five pounds. Social animals, otters travel within
a home range of 15 square miles in family units of four to five
individuals.
Uniquely adapted
to its aquatic environment, the otter has webbed toes, a water-repellant
coat, and the ability to close its ears and nostrils while diving.
The otter also has long whiskers that help it to detect prey underwater.
These adaptations allow the animal to exist chiefly on a diet
of fish, which they catch with their superior underwater swimming
skills. Otters are also known to eat frogs, turtles, snakes, crayfish,
and an occasional bird.
Beavers
are very important to otters. If beavers frequent a
particular area, there is a good chance that otters
will also be found there. The ponds created by beaver
dams are prime habitat for the otter. Otters often use
the abandoned dens of beavers as sleeping quarters.
If a beaver den is not available, they also may be found
in hollow trees or between rocks or roots, building
nests out of sticks, leaves and grass.
Otters
are active and curious. They spend much of their time
playing with each other and exploring their environment.
While other animals may play to practice hunting and
survival skills, otters often play for pure enjoyment,
a rare trait in animals and usually a sign of higher
intelligence.
Mating
takes place in the fall after rival males battle for
a mate. After a gestation period of up to 270 days,
the female otter gives birth to one to three young,
called kits, in a den with an underwater entrance constructed
beneath the bank of a stream, river or lake. The mother
otter defends her kits fiercely and they remain with
her as a family unit for over a year.
The otter
has few natural enemies other than man, who trap it for its rich,
thick pelt, and who also have lowered populations through habitat
destruction and roadkill. Look for otters in larger streams or
rivers where food is abundant and the water is unpolluted and
quiet. The best time to look is early morning or evening.
American
Alligator (Alligator mississippiensis)
American
alligators, the largest land reptile in the United States, are found
throughout the Coastal Plain of South Carolina. These crocodilians
grow from 8 to 12 feet in length, though individuals up to 18 feet
in length have been found. Despite their size and their reputation,
they are generally not a threat to people. In a quarter century,
there have been only six documented alligator attacks on people
in South Carolina and none were fatal. An alligator’s diet consists
of invertebrates, fish, birds and small mammals. Generally if a
person is attacked, it is because the alligator was protecting itself
or its young and not because it was seeking a meal. Like any wild
animal, though, it is a good idea to keep a respectful distance
from an alligator, and not to engage in any activity the animal
finds threatening such as approaching it.
Alligators
are found in freshwater swamps, marshes, impoundments,
lakes, ponds and the backwaters of large rivers. Alligators
are cold-blooded aquatic animals that depend on the
sun for warmth and freshwater aquatic habitats for food.
For this reason, they are found only in the Southeastern
United States, where the climate is warm and water is
plentiful.
Adult
alligators feed on fish, turtles, aquatic birds, water
snakes and small mammals. Many alligators also feed
on carrion. Alligators are carnivores, but they are
also opportunistic feeders, and will not turn down an
easy meal.
Alligators
are often found in the day basking in the sun on the
shore of some body of water. Unable to maintain a constant
body temperature, alligators depend on external sources
to raise or lower their body temperature. Absorbing
sunlight warms the alligator and prepares it for evening
hunting. If it becomes too warm, it will move to the
water to cool off. In the winter when temperatures drop,
alligators go into a semi-dormant state, and generally
do not become active again until March.
Female
alligators are very protective mothers. In June the
female builds a mound made of dirt and vegetation about
seven feet in diameter and one to two feet in height.
In the middle of this mound she digs a hole and lays
15 to 80 eggs. This nest acts as an incubator that keeps
temperatures for the eggs in the upper eighties. During
this whole time, the mother watches the nest with a
protective eye and keeps hungry predators away. When
the eggs begin hatching in September, the mother helps
the young by digging them out of the nest and even gently
carrying some of the young in her jaws to the water.
It is amazing that jaws capable of exerting 3,500 pounds
of pressure per square inch on a prey item can be used
for such delicate actions. For up to a year the mother
will stay with the young to protect them from predators.
During this time, the young alligators feed on insects,
crayfish and frogs.
Atlantic
Bottlenose Dolphin ( Tursiops truncatus)
The
Atlantic bottlenose dolphin, commonly misidentified on the South
Carolina coast as a porpoise, occurs from Cape Cod south through
the Caribbean and Gulf of Mexico to northern South America. Common
along the entire southeastern coast, it frequently ventures up tidal
creeks and rivers into virtually freshwater. The bottlenose dolphin
grows to twelve feet in length.
Dolphins
typically breed in the spring, and after a gestation
period of twelve months, one calf is born. At birth
the three-foot long dolphin calf weighs approximately
25 pounds. The calf will stay with its mother and nurse
for 12 to 18 months before fending for itself. Dolphins
live for 25 to 40 years on a diet comprised primarily
of fish, squid, and shrimp. The bottlenose dolphin requires
about 10% of its body weight in food daily.
Dolphins
use echolocation to help them to pinpoint the location
of prey. The underwater use of sound to locate food
is similar to the terrestrial echolocation used by bats.
Dolphins occasionally use complex herding formations
to capture fish. In shallow tidal creeks, a pod of dolphins
sometimes herds fish towards land. When the fish are
cornered, the dolphins rush in and knock the fish onto
a sand bar or mud bank with its powerful tail. The dolphin
then pulls itself out of the water onto the bank and
retrieves its stranded prey.
To
prevent sharks from invading their territory, dolphins
are known to attack the sharks by ramming the shark
in the gills with their rostrum (snout) in an effort
to force the shark to leave the area. On occasion dolphins
have been observed to surround a shark and take turns
either ramming the shark or tossing it into the air.
It is unknown if this behavior is a serious attempt
to injure the shark or simply a playful game.
Dolphins
also display cooperative behavior. Healthy dolphins
will come to the aid of another sick or weak dolphin.
The two stronger dolphins will flank the sick animal
and guide it to the surface by supporting it under a
pectoral fin. On rare occasions, the bottlenose dolphin
has helped humans in distress in the water. This usually
involves a drowning person that the dolphin pushed to
the safety of shallow water.