Showing posts with label mammals. Show all posts
Showing posts with label mammals. Show all posts

Sunday, November 27, 2011

Visiting the relatives


We share around 98% of our genes with chimpanzees, according to the San Diego Zoo. In Kibale National Park, Uganda, these relatives rule the forest.


Chimpanzees construct nests to sleep on at night

We visited five different forests between Uganda and Rwanda that are known to support populations of chimpanzees. In our experience, they are not always easy to find and even when you do see them, it may only be a brief encounter. Most tracking hikes give you just a brief shot at observation in the wild. However, in Kibale, you have the unique option of tracking them for the whole day. On November 5, at 6 am still in the dark of morning, Michele and I jumped off the back of a motorcycle and began our search for Pan troglodytes.


Our guide had been a ranger in the park for many years. We started searching for a group of chimpanzees not-yet-used to people but discovered only smashed figs from a recent meal. We later found a lone mother and child collecting and eating fruits in a tall fig-like tree. We eventually followed a habituated group (used to human observation) as they wandered the forest. We counted 18 individuals in the group, but a few more could have been out of sight. Because they were used to humans, we could sit/stand around ten meters back observing them while they ate, groomed, played, climbed, and rested. We even saw a skirmish with olive baboons!


At around 2:30 pm, it started to rain. A flurry of excitement filled the chimpanzees, and our guide told us "the rain dance" was imminent. Male individuals ran back and forth on two legs and used their hands to shake and pull young trees (normally they walk on all fours using feet and knuckles). Other individuals crowded close to big trunks to avoid the bursts. We watched until every chimpanzee had seemingly ran off or vanished into the rain. 


Even though chimpanzees and humans appear very different from each other on the surface, consider that our cells are nearly identical in form and function, and we have nearly identical internal anatomies. Check out more similarities and differences between humans and chimpanzees


Humans are in such a different world than chimpanzees, but we share the same earth, the same biology, and a common history. Various populations of chimpanzees in Africa total up to two hundred thousand (200,000 chimpanzees). We are at a population of seven billion (7,000,000,000 humans). Our worlds collide as our demands on the forests of Africa grow. Is the earth big enough to support both species? Will we be able to visit our closest genetic relative in the future? I do not know the answer to these questions, but I hope the answer is yes. 

Saturday, November 12, 2011

Leave only footprints

Hippo prints, Murchison Falls National Park, Uganda. Note the tire track
on the right came before the hippo passed.


Tracks from the past
Impressions in the mud
Here but now gone
Our footprints linger on


Leopard print, Ngorongoro Conservation Area, Tanzania

Take only memories
Leave only shapes
Elephants, hippos,
Leopards and apes


Chimpanzee foot and knuckle prints, Kibale National Park, Uganda

Casts left in African soil
As animals make their way
The stories mud could write
Of the details of the day


Elephant print, Ngorongoro Conservation Area, Tanzania

Rain falls heavy from the sky
Washing away yesterday’s marks
But leaving the dirt soft
For fresh footprints to start


Human footprints, Rwanda

Monday, October 31, 2011

Run like an antelope

Thomson's gazelle (Gazella rufifrons) in Ngorongoro Conservation Area,
Tanzania. Look at all those flamingos in the background! What a life, to
run around free and enjoy the birds, without a care, except for lions,
cheetahs, leopards, and hyenas, of course.

The name antelope refers to a wide variety of mammals. Although antelopes are extremely diverse, they all share some basic characteristics.

White-bearded gnu (a subspecies of blue wildebeest (Connochaetes 
taurinus albojubatus) in Ngorongoro Conservation Area, Tanzania.

Antelopes are even-toed, hoofed mammals. They share this foot morphology with hippopotamuses, warthogs, giraffes, and deer, but none of those are "antelope."

Female eland (Taurotragus oryx) in Akagera National Park, Rwanda.

Antelope are classified in the family "Bovidae" along with cattle (buffalo) and sheep. Something that distinguishes the Bovids from other even-toed, hoofed mammals is that Bovids have horns.

Kongoni (hartebeest) (Alcelaphus buselaphus cokei) in Serengeti 
National Park, Tanzania.


Topi (Damaliscus lunatus) in Akagera National Park, Rwanda.

Antelope have horns, not antlers. Deer, for example, are not antelope. If you think about the common white-tailed deer, you may remember the male has antlers. His antlers branch; horns of Bovids do not branch. Additionally, antlers are shed each year and then regrown. Horns are permanent and do not shed.

Female waterbuck (Kobus ellipsiprymnus) in Akagera National Park, 
Rwanda.

Most antelope species also exhibit sexual dimorphism. Sizes, coloration patterns, and the presence of horns may differ between the males and females depending on the species. Adult males of all antelope always have horns, but some females have them too. Male and female elands, for example, both have horns but differ in their shade of brown and how much hair they have on their necks. Male impala have horns but females do not (males and females also differ in size but otherwise look the same).

Bush duiker (Sylvicapra grimmia) in Arusha National Park, Tanzania.

Kirk’s dikdik (Madoqua kirkii thomasi) in Tarangire National Park, 
Tanzania.

Antelope vary greatly in size. Eland males can weigh nearly 950 kilograms whereas Kirk's dikdik reaches just 7 kilograms. Some dikdik species are even smaller (2-3 kilograms).

Bohor reedbuck (Redunca redunca) in Serengeti National Park, Tanzania

Some antelope species live in large herds, such as wildebeest and impala, but others like duikers live alone or in small groups. In some species, like waterbuck and gazelles, in the breeding season, the males split apart from herds and defend a territory. 

Impala  (Aepyceros melampus) in Serengeti National Park, Tanzania

Uganda Kob (Kobus kob thomasi) in Murchison Falls National Park,
Uganda

All antelope are grazers. What they graze upon depends on their habitat. Antelope inhabit ecosystems from desert to grasslands to dense rainforests. They eat plants and serve as the link in the food chain between the sun and the predators.

Male bushbuck (Tragelaphus scriptus) in Akagera National Park, Rwanda

Big antelope are preyed upon by lions, cheetahs, leopards, and hyenas, but smaller antelope are eaten by a wide variety of predators. Life as an antelope is a life on the move, in search of food and avoiding being the food. Run antelope run!

Works consulted
  • Gomez, W., T. Patterson, J. Swinton and J. Berini. 2011. "Bovidae" (On-line), Animal Diversity Web. Accessed October 31, 2011 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Bovidae.html.
  • Kingdon, Jonathan. The Kingdon Pocket Guide to African Mammals. Princeton and Oxford: Princeton University Press, 2004.
  • Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey. "Horns and Antlers." 2006. The Animal Diversity Web (online). Accessed October 31, 2011 at http://animaldiversity.ummz.umich.edu/site/topics/mammal_anatomy/horns_and_antlers.html
  • "Mammals: Antelope." 2011. Zoological Society of San Diego. Accessed October 30, 2011 at http://www.sandiegozoo.org/animalbytes/t-antelope.html


Wednesday, October 26, 2011

Zebras, rhinos, and giraffes oh my! A mammal extravaganza

Common zebra (Equus quagga) in Ngorongoro Conservation Area,
Tanzania

There are roughly 5,000 mammal species on Planet Earth. Some extraordinary species inhabit East Africa. Enjoy them!

Black rhinoceros (Diceros bicornis) in Ngorongoro Conservation Area,
Tanzania


All mammals exhibit three basic characteristics. All mammals have three middle ear bones that help transmit vibrations from the eardrum to the inner ear. All mammals have hair at some point in their lives. All female mammals produce milk from mammary glands (modified sweat glands) to nourish their offspring. 


African elephant (Loxodonta africana) in Serengeti National Park,
Tanzania


After those three standards, although there are other shared characteristics, the forms of mammals are very diverse. From mice to elephants (and whales if you really want to go big), mammals vary in size. From giraffes to bats, mammals vary in body shape and method of locomotion. From squirrels to lions, they differ in what they eat and how they get.


A species of zebra mouse, Agahozo-Shalom Youth Village, Rwanda

Giraffe (Giraffa camelopardalis) in Tarangire National Park, Tanzania


For more about mammals, see the previous posts “Happy Mother’s Day” (about mothers and nursing their young), “Big cats and the endless plains of the Serengeti,” “Abirthday with gorillas,” and “Monkeying around.” Look forward to “Run like an antelope,” an upcoming post about the many antelope of East Africa. 


A species of fruit bats, in trees on the shore of Lake Kivu, Rwanda

Common warthog (Phacochoerus africanus) in Tarangire National Park,
Tanzania


Black-necked rock hyrax (Procavia johnstoni) in Serengeti National
Park, Tanzania

Brindled gnu (blue wildebeest) (Connochaetes taurinus) (left) and
golden jackal (Canis aureus) in Ngorongoro Conservation Area,
Tanzania

Boehm's squirrel (Paraxerus boehmi) in Mabira Forest Reserve, Uganda

A young African lion (Panthera leo) in Ngorongoro Conservation
Area, Tanzania

Works Consulted
Wund, M. and P. Myers. 2005. "Mammalia" (On-line), Animal Diversity Web. Accessed October 26, 2011 http://animaldiversity.ummz.umich.edu/site/accounts/information/Mammalia.html.

Wednesday, July 13, 2011

Big cats and the endless plains of the Serengeti

A leopard rests in an acacia tree next to a stream.  At night, they stalk
their prey and pounce, but rarely chase. Leopards are widespread
throughout Africa, but this is the only one I have ever seen.

When grasses bloom, the herds follow. Lurking in places beneath the eye, the cats await their next feast. With muscles tensing, jaws opening, claws extending, they pounce!

Read on for lions, cheetahs, and the endless plains...


Sunrise over the Serengeti. Let the day begin...

In the Masaai language, according to our guide, "Serengeti" translates to "endless plains."  Filled with grasses and occasional trees, Serengeti National Park covers 1.5 million hectares. It stretches into other nearby parks in Tanzania and into the Masaai Mara of Kenya. To the human eye, it is indeed an endless plain.


The male African Lion, Panthera leo, lifts his head from rest. When prey
is plentiful, lions may sleep up to twenty hours a day. 

Although it can get warm in full sun, the Serengeti plains rise from around 1000 to nearly 2000 meters. I think where we stayed was around 1700 meters above sea level. With previous impressions of a dry and sun-filled landscape, I was surprised at how cool it was in the morning and as the sun set.

A pile of female and young male lions sleep nearby the previously-pictured
male.

The availability of water is a major limiting factor in the growth of plants. Where there is not enough water for trees, grasses often blanket the land.

The spotted hyena, Crocuta crocuta, is a peculiar predator that is related
to cats. Although they have a reputation as scavengers, they actually hunt
most of their food. They have been widely killed by humans and often fight
over kills with lions. Find out more.

By streams and their adjoining marshes, trees find enough water to grow. Sometimes the only break in the flat plain is a line of trees following the river.

This spotted carnivore, Acinonyx jubatus, is the fastest land mammal.
Although it once roamed several continents, the cheetah is now endangered
and can only be found in northern Iran and sub-Saharan Africa. 

We found many animals near the water sources. Ducks and sandpipers were on the water, weavers constructed their nests on the branches of the nearby trees, and vultures sat atop the crowns waiting for the scent of flesh. 

The herd of African buffalo is tiny compared to the expanse of the plains,
even though each buffalo (Syncerus caffer) is 2-3 meters long and
on average weighs 700 kilograms.

There was never a dull moment in the Serengeti. Even when all animals seemed to disappear, the sounds of the wind rustling the grasses provided a soundtrack as heavy clouds pushed along the sky.

Hyenas and lions are the main predators of the buffalo.


Just look at what the hyenas are watching. A herd of Thomson's Gazelle
grazes, drawn to this predator-rich land by an even richer store of grasses.
High numbers of Thomson's gazelle, Grant's Gazelle, Zebra, Topi,
Bohor reedbuck, hartebeest, impala, wildebeest, buffalo, small mammals,
and even elephant provide opportunities for the Serengeti's predators.

So flat and big you can see an individual rainstorm start and stop.

The Serengeti ecosystem is protected by the Tanzanian government as a National Park and several other conservation-designated areas. Still, it is threatened by human activities and invasive species. Activities outside the park can affect the migratory animals that flow in and out of the park boundaries.

Panthera pardus is hunted for its skin and killed by cattle ranchers. 

All three of the big cats shown in this post are either endangered, vulnerable, or conservation-dependent. Places like the Serengeti are essential for their survival. As we humans exert so much influence, we must make choices about the kinds of impacts we make. Will the plains continue to support millions of wandering animals? Will lions, cheetahs, hyenas, and leopards have a home in the 21st century and beyond? Will we keep places like the Serengeti? 

Kopjes are small rocky hills that generally covered in trees and shrubs.
They provide habitat and cover for many creatures that venture out
into the grasses by day or night. Some animals even specialize in
staying at these rocky islands in the sea of grass.

Water holes and rivers are essential hydration spots for the animals of the
Serengeti. In the dry season, these are the easiest places to find a wealth
of big animals who need a drink. In the wet season, animals
spread out over the land.


There is so much in the Serengeti, but grass and sky dominate.
Hopefully this beautiful place will be "an endless plain" forever.

Works Cited

Harrington, E. and P. Myers. 2004. "Panthera leo" (On-line), Animal Diversity Web. Accessed July 13, 2011 http://animaldiversity.ummz.umich.edu/site/accounts/information/Panthera_leo.html.

Hunt, A. and P. Myers. 2011. "Panthera pardus" (On-line), Animal Diversity Web. Accessed July 13, 2011 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Panthera_pardus.html.

Law, J. and P. Myers. 2004. "Crocuta crocuta" (On-line), Animal Diversity Web. Accessed July 13, 2011 http://animaldiversity.ummz.umich.edu/site/accounts/information/Crocuta_crocuta.html.

Mulheisen, M. and N. Knibbe. 2001. "Acinonyx jubatus" (On-line), Animal Diversity Web. Accessed July 13, 2011 http://animaldiversity.ummz.umich.edu/site/accounts/information/Acinonyx_jubatus.html.

Newell, T. 2000. "Syncerus caffer" (On-line), Animal Diversity Web. Accessed July 13, 2011 http://animaldiversity.ummz.umich.edu/site/accounts/information/Syncerus_caffer.html.

2011. "Serengeti National Park" (On-line). UNESCO World Heritage Centre.  Accessed July 13, 2011. http://whc.unesco.org/en/list/156/