One our class assignments includes analyzing our field notes and field guides then explaining the behavior of animals we saw...
Herbivores:
Burchell Zebras:
The zebra’s most prominent
characteristic is its stripes. Each zebra has a different stripe pattern (like
fingerprints) and can identify each other by memorizing each other’s patterns.
In particular, baby zebra’s memorize their mother’s stripe pattern so that they
can identify her easily amongst the herd. A zebra’s stripes also serve as a
camouflage technique from predators— because many predators lack an advanced
color vision, the black and white stripes break up the image and create a
pseudo shadow appearance. This can help the zebra remain unspotted and gives it
a greater chance of survival.
Their mane stands erect and is
short and neatly chopped. The exact purpose of this is unknown; however, when
the zebra is sick, its main will droop to one side. This sign of poor health
could deter others from mating with a weak zebra and make the gene pool
stronger.
Zebras live in family groups
where it is typical to find a couple males, females, and a baby. On our 4th
day of safariing, in the afternoon, we saw a stallion who put himself in
between us and his herd and was “displaying” himself. Stallions
are very defensive over their family groups. By threatening potential threats
and alerting his group to dangers, they are safer from predators.
Baby zebra’s can nurse for up to
a year and remain with their mother during this time for protection until they
have grown enough to fend for themselves.
Savannah Giraffes
The splotches of brown on gold on
a giraffe’s coat provides excellent camouflage. It breaks up the landscape when
looking from afar and looks like shadows created from tree branches. This
decreases the giraffe’s chance of being spotted by predators.
Their long neck allows them to
feed high up on trees where other animals cannot reach. They are also the first
to spot danger because they are so high up. Giraffes spread their legs apart in
order to reach their neck to ground. This is how they drink and reach low lying
leaves. To avoid competing with each other, females graze lower on trees while
males graze higher up.
A giraffes horns are used for
protection. When fighting, they use their long neck like a baseball bat to
whack their opponent. During one of the drives, the other car saw 2 giraffes
fighting. I unfortunately was not with them, but they told us that the stronger
giraffe was using its neck to repeatedly pound its victim. Before developing,
baby giraffes Male giraffes are larger overall and have bigger horns than
females. Before developing, babies have shaggy horns, but due to fights, males
often wear off the hair on their horns. Females, on the other hand, are smaller
overall and have slender horns with hair on the top. This difference between
genders has developed because males are territorial and require larger horns to
defend their ground.
Giraffes are one of the only
animals able to eat from the acacia tree. In order to get around the acacia’s
thorns, giraffes have evolved a long, hardened, dexterous tongue that can
easily eat around them.
There is no set social structure
for giraffes; however, mothers with young will congregate together for extra
protection. This increases their young’s chance of survival because other
vulnerable babies are around that the predator can choose from.
On our walking tour, the giraffes
were not threatened by us; however, if they are threatened, they will move
straight towards the predator. Predators often have chasing instincts, so
moving towards them throws them off guard. We also examined their dung on the walking
tour and discovered that one can identify the sex of a giraffe by looking at
their dung. Females’ dung is pointed on one side and flat on the other while
males’ dung is flat on both sides.
Warthogs
Often while driving, we’d see
warthogs trotting through the grass. At one point, we saw several babies emerge
out of a burrow and follow their mother. As they run, it is difficult for young
warthogs to follow because the grass is taller than them. Therefore, their tail
that stands straight up while running is a following signal.
They live in ground holes that
are initially created by aardvarks digging into termite mounds. The warthog
then scrapes the hole out even more, creating a burrow in which they can raise
their young and hide from predators. When getting in their burrow, they always
back in with their tusk facing the outside. In this position, a predator who
tries to attack the warthog will likely run head-on into sharp tusk that can
injure it.
To eat, they kneel down and are
able to eat roots and short grasses that many other herbivores do not eat. This
prevents competition.
On day 7 in the afternoon, we saw
a warthog with its hair standing up. This is called pilo erection and is a fear
response. They look bigger and more threatening when their hair is sticking up;
therefore, it can possibly deter predators from attacking.
Hippos
Hippos thrive in the water during
the day and move onto land to graze at night. This allows them to spend their
time conserving energy and affords them the luxury of having to eat less grass.
During the day, they secrete a sun-screen like chemical that protects their
sensitive skin from the sun.
Hippos are vegetarian (excluding
a few rare exceptions) and come ashore to graze during the night.
On day 8, we saw 2 hippos (one
male and one female) in a lake. One lifted its head out the water, opened its
mouth, and made grunting sounds. This is threatening behavior and used to
defend its territory. In this pond, there was only one female, but typically
they have a harem structure with one male and multiple females.
Kudu
Their brown coat with white
stripes serves as camouflage by creating pseudo shadows and hiding them from
prey.
A noticeable characteristic of
the males are their large horns (they have the largest horns of any African
antelope). These are used for defense as well as for mating.
Impala
A two-toned coat acts as
camouflage to predators by blending into the environment and creating a three
dimensional shadow appearance. This helps them avoid being spotted by
predators.
Impala are mixed eaters and eat
both grass and trees. Often they will be found in conjunction with other
herbivores such as giraffes, zebras, wilderbeast, or warthogs. Each animal is a
different height and has different “eating zones.” This allows them to stay
together for safety, but not compete against each other for food.
Impala maintain safety in numbers
by staying in large herds. It is a lottery for them as to who will get picked
off next; but by doing this, the weak get picked off and the strong survive,
increasing the genetic gene pool. November is the peak of the new babies birth.
All impala females have young within 2 days of each other. When an entire herd
of say, 30, has young, it is expected that a few will fall prey. However, the 5
or so that do is a small price to pay for the 25 that will survive.
During mating season, there are
three different social structures for impala: a harem herd, bachelor herd, and
a solitary male. Harem herds consist of 20+ females and one dominant male. When
a male grows up enough to mate, he is rejected from the herd. From there, he
joins a bachelor herd that consists of males of different ages. There he will
wait until he is strong enough to defeat the dominant male of a harem herd.
Males often practice fighting and are ranked within the bachelor herds. On day
2 we saw 2 males thrashing (butting heads) to assert which one is more
dominant. When a male decides to challenge, he becomes solitary and selects a
territory to defend. This leaves it venerable to predators, but is necessary to
mate. When females cross his path, it will then challenge the dominant male in
the hopes of winning the females over. This method of mating increases genetic
diversity.
Metatarsal glands on the back of
their ankles releases a musky smelling chemical when running. Pre-orbital
glands on their face secrete chemicals as well and impala rub their faces on
things to mark their territory. These chemicals are used to find mates and
prove their status as a male.
On our walking tour, a male
impala was grunting. This behavior either means he is getting ready to
challenge a male or herding his females to safety.
Waterbuck
A circle on their butt acts as a
following signal. While running through the bush, young waterbuck can easily
see where they are going and follow.
When approached, they stand stock
still and stare. Predators detect movement, so by doing this, they are trying
to blend in with the environment.
Dikei
A brown coat is used for camouflage and
blending in with their surroundings. Because of their tiny size, they use
concealment as a survival strategy. They have a very square build compared to
the steenbok’s lean build. They are able to maneuver quickly throughout the bush
felt and hide from predators.
These are pair bonding animals
and will either be in groups of a female and male or be alone. Pair bonding
saves them the energy of finding a new mate and allows them to focus more on
survival. When one is spotted, it is almost certain that its mate is nearby;
however, the two do not stand near each other for survival purposes.
Vervet Monkeys
On day 2, these animals made an alarm call
when we approached and hid in their trees on the river bank. Eventually, they
determined we were not a threat and ventured out of hiding. They stick together
in groups and alert each other to threats. Looking out for each other helps
them survive.
Buffalo
Buffalo use olfactory senses to
smell threats. When we approached on foot (Day 2), the herd got a whiff of our
scent and took off in a stampede. Being able to sense predators before they are
close enough to kill gives them an advantage. Additionally, stampeding poses a
danger of being trampled to any animal who attempts to take one down. When
alerted to a threat, they access it and depending on the situation, either
flight or fight.
Males have a “part” in the middle
of their head called a “boss” that is actually a thick, hardened bone. This
protects their skull in fights.
They group in large herd that can
contain around 100 buffalo. Because they are social animals; this
allows them more access to mates. Young buffalo also learn faster and become
independent sooner. This helps them survive by outgrowing their vulnerable
stage quickly.
The older dominant males are the
primary ones who mate with the females of the herd. When searching for a mate,
the male partakes in “flemming.” The male tastes the hormones in females’ urine
and can tell if they are in estrus or not. If they are, they will mate.
Steenbok
These tiny brown antelope are
able to bound through the bush quickly and are less noticeable to predators
because they are so small.
Steenbok are pair bonders and
will pair for life unless something happens to their partner. This allows them
to spend less energy trying to find mates and more energy on surviving.
Hare
Hares, in contrast to rabbits, are born with
their eyes open and with hair. This increases their survival because they are
not as reliant on their mother when born.
Elephants
The size of an elephant helps protect it from
predators. They can weigh around 3-4 tons, making it very difficult for
anything but a large pride of lions to successfully kill it.
Elephants particularly like
marulla trees. They will strip the tree of its nutritious bark by scraping it
off with their tusk, eat its fruits (during feb), and push it down to eat their
leaves.
We saw 2 male elephants on day 6
that had mud all over them. Elephants cover themselves in mud and then rub
against trees to remove ticks and parasites. One of these males put his ears
back and shook his head. This behavior means he was agitated.
Elephants will only mate when a
female is in estrus and a male is in musk. Often it is the mature, dominant
males that go into musk when a female is in estrus. They secrete a chemical in
their temporal gland that increases their testosterone, sex drive, travel more,
and makes them spend less time eating and drinking. Musk is therefore very
taxing on males. When ready to breed, they move as far away from their birth
place as possible to increase genetic variation. Once mated, females gestate
for about 22 months and typically give birth around the end of summer
(feb/mar).
On day 2, we also saw a male
elephant that was about 12-13 years old. He stayed close to the herd, yet was
quite out of range of them. This is because the females are beginning to kick
him out. In order to have genetic variation, males must leave their family
herds in order to find mates with different genes.
The same day, we saw a herd of
elephant mothers with babies. One of the mothers trumpeted at us and even
bluffed a charge at the other vehicle. This protective behavior is critical for
their babies to survive. A protective mother can deter a predator from
attacking because it’s not worth the risks. Once determining we were not a
threat, the female mother kept a watchful eye and occasionally raised her trunk
in the air. This is how she smells us and determines if we are dangerous or
not. The baby with her looked to be about 2 years old. It was still trying to
suckle but the mother was preventing it. When the dominant female turned or moved,
the others followed. This leadership helps the herd maneuver safely throughout
the bush.
We examined elephant dung on our
walking tour; because elephants only digest 40% of what they eat, there were
many pieces of undigested fruit, seeds, and grass. The undigested material is
useful for many animals to utilize.
At the elephant whisperers, they demonstrated
just how smart elephants are. They can remember roughly 80 commands and have astonishing
memories. In the wild, the matriarch remembers where they have eaten for years.
This allows her to guide her herd to new grazing areas. If the leader is
killed, the herd will be thrown into chaos and may starve.
White Rhino
As the 2nd largest
land mammal in the world, they have virtually no predators (besides humans). A
large horn protruding from their nose helps them to defend themselves. If
something threatens them, they will charge blindly towards the threat. Bad eye
sight makes them even more dangerous because they are unpredictable and will
unknowingly run you over.
White rhinos eat grass which
allows them to coexist with the black rhino that feeds on trees.
To mark their territory, they
kick their dung around. This deters other males from entering their area and
gives the marker more access to females.
A rhino horn is valuable in India
because many believe a myth that it can cure cancer and other diseases. A kg of
rhino horn powder sells for $80,000 and a whole horn can sell for ½ million.
Poachers therefore hunt the rhino for their horns and as a result has
endangered it. The reservation injects poison into their horn in an attempt to
prevent this.
On day 8, we spotted 2 male
rhinos grazing. They have to constantly eat in order to maintain their massage
body weight.
Wilderbeast
A sloping back is conducive for
long distance running, and other features, such as their coat, allow them to be
camouflaged from predators.
Wilderbeast secrete a pheromone
that relay to other wilderbeast information such as its age, dominance, gender,
territory, etc. This helps males find a mate and size up competitors. It also
tells males which females are in estrus and ready to mate. We saw a male rubbings
his scent onto things and leading his herd off. This is how they mark their
territory and tell others that this is his land.
At one point, we saw a solitary
wilderbeast with several impala. The wilderbeast was likely staying with them
for protection while they were within his territory.
When walking through the bush, a
wilderbeast spotted up, snorted, and moved away from us. It snorted to alert
the females to predators. This protective behavior can save the lives of member
of the herd.
Baboons
One baboon can weight up to 90
lbs. In a group, there is one big male who is in charge. They have an oligarchy
structure in which all males are ranked above all females.
They are very intelligent and
cause damage to homes because they can break in easily. As a result, many are
shot.
Carnivores:
Dwarf Mongoose
Jackals
Jackals are scavengers and feed off of the
leftovers from lions and other large predators. They are also pair bonders and
spend less time and energy searching for mates.
Hyenas
Hyenas live in a matriarchal
society where every single woman is more dominant than even the highest ranking
male. It is difficult to determine their gender because females are physically
bigger and have a “pseudo penis” that consists of enlarged genitals.
On day 4 we saw 3 hyena pups.
They raise their young in old warthog or aardvark dens, but the puppies will
modify it to create little chambers in which they can tuck themselves away.
They stay in this den for about 1-2 years. The pups we saw were probably about
a year old and were just getting ready to leave the den.
A slanted back allows them to run
long distances. To catch prey, they chase them until they are exhausted and
cannot run anymore. From there the hyenas move in for the kill. They do not
have retractable claws, so they cannot climb; however, their claws provide
traction for running.
We saw a carcass of a giraffe
that had been chewed up by a hyena. Hyenas are the only animals that can crunch
bone with their teeth. By opening up the bone, other animals can therefore get
inside.
We examined the dung of a hyena
on our walking tour; it was very chalky and white. This is a result of their
diet that includes a lot of bone. The calcium turns their dung white.
On day 7 in the afternoon, we saw
a hyena resting in a puddle of water. They do this to cool themselves down on a
hot day.
Nile Crocodile
We saw a couple crocs throughout the trip
that were swimming in lakes. Crocodiles feed on turtles, fish, and other small
animals. They can live alongside hippos because they do not compete against
each other; however, if a croc comes too close, the hippo would overpower it
and could bite it in half.
Leopard
We first saw a leopard sitting on
a man-made watering hole. It jumped in, but after a few minutes it hopped out
and casually laid in the grass. Resting during the day is typical of leopards
because they are conserving their energy for hunting during the night. These
big cats have spots that help it blend in with its surroundings and stalk up on
prey without them noticing. They are also built for strength and
power—necessary to take down larger prey.
We saw another leopard during the
afternoon drive on day 7. As it walked it sprayed urine on trees. This is how
they mark their territory. On of its eyes were injured and it kept licking its
paw, so we suspect that was injured as well. These injuries were likely from a
fight with the larger male leopard that controls that territory. The smaller
leopard was in his territory because he was looking for a female that was in
that area a couple years ago.
On day 8, we saw the same leopard
we had seen on day 7. Birds made alarm calls at it to alert others that a
predator is in the area.
Lions
Lion’s social structure consists of one male
and several related females. Once a lion grows to adulthood, he is forced out
of the group and becomes solitary. He then waits until he grows strong enough
to challenge the alpha male of a new pride. This system increases genetic
diversity. One example of how lions are drawn to others with different genes
was seen the first night. Two female lions slept on the fence line for 6 months
because they were trying to get to the male on the other side. Likewise the
male (seen the following night) was also on the fence line hoping to get across
and mate with those who had “fresh genes.”
Cheetahs
On day 7 in the afternoon, we saw
a pair of male cheetahs laying down. They require a lot of resting to conserve
their energy for running. The cheetahs then got up and started walking, panting
as they went. They pant to cool themselves down.
The thin frame, large lungs, and
muscular legs of a cheetah are all physical factors that contribute to its
speed. It uses its speed to chase down prey.
To prevent competition with lions
and leopards, cheetahs often hunt during the day. Even still, however, they
often fall prey to lions.
Honey Badgers
A honey badger’s aggression;
loose skin; and fearlessness allows it to defend itself from predators and be a
successful carnivore.
As part of the weasel and
mongoose family, it preys on small animals and scavenges for eggs and
leftovers.
One of their favorite things to
eat is honey. They will crack open a bee hive and despite being stung by the
whole swarm, will sit there and eat.
No comments:
Post a Comment