The African Great Migration and Its Significance

The last few days of our expedition gave meaning to our adventure. We were in the Kenyan Maasai Mara, thrilled by the larges animal migration of on Earth.

On the cover photo is a group of blue Wildebeest. AKA the common wildebeest Connochaetes taurinus) it is a large antelope found in Kenya and Tanzania.

One wildebeest is not photogenic. There is never just one. Tens of thousands of them live and move together as one massive organism. Hundreds of thousands of mixed species of animals move with them and between each other during the great wildebeest migration.
Migration map We were in the Maasai Mara during the last four days of August.

The Maasai Mara of Kenya is contiguous with the planes of the Serengeti National Park and the Tanzanian National Park. All are part of the Serengeti plane. These images are from the Kenyan Maasai Mara National Reserve. It was the most favorable point to observe the Great Migration when we were there. As the weather changes from dry to the rainy season the grass regrows. It is the grass which provides food for the grazing animals. This is irresistible to the wildebeest, zebra, impala, buffalo and other animals who follow this growth by the millions. The dead grass remains after the tops have been eaten to the ground or burned off. The rain brings a fresh regrowth. This regrowth replaces the razor-sharp stubble with soft young plants.

One of the most thrilling wildlife spectacles on earth was spread before us like pepper on a salad. We stopped to watch this ancient migration sight that this area supports. You can see in every direction that the savanna is covered by hundreds of thousands of animals. It is hard to comprehend that they actually number in the millions. They are visible to every horizon, slowly moving to follow the fresh growth. They meander about eating and mingling, occasionally fighting and challenging one another for mating or protecting one another from the daily challenges of survival, reproduction, and predation. For reasons unknown to us they may gallop along following some instinct or stamped when startled or frightened. It is this cumulative picture of integrated behavior based on soil, seasonal weather, prolific plant life and a massive accumulation of thousands of animal species which underscores the interdependency of this huge ecosystem.

Migrating animals wandering from one side of the horizon to the other. View of the north.

We did cross the Mara river and its tributaries where crocodiles and hippopotamuses were swimming or simply resting. The hungry crocodiles were ready at a wildebeest crossing to take advantage of the weakest or most vulnerable animals. We did not see this classical behavior but none-the-less the trap was set. Predators and scavenger animals follow this migration in the ladder of primacy with the lion at the apex.

The Mara river teeming with crocodiles waiting for the stampede.
The blue wildebeest, keystone animal of the Serengeti, Maasai Mara. Running with the group on its way into the future.

The wildebeest is the keystone animal of this ecosystem. It is the primary consumer of the grasses. It has a high reproductive rate. It is the resource upon which all of the carnivores and scavengers depend. They till and fertilize the soil. A single calf is born after 8.5-month gestation. Bands of female wildebeests are in control, leading the entire herd towards new grasslands. In the mid-20th century, the wildebeest population was decimated. The herd was cut down to one third of its normal size because of the rinderpest viruses (a variant of the measles virus). It originated and was spread from domestic livestock. As a result of loss of the grazing animals the grass lands grew uncontrolled. This over-growth subsequently changed the natural fire regime to an intense wildfire which burned nearly the entire Serengeti. This was an ecological disaster. Millions of domestic animals also died. Plant and animal species collapsed. Because of a massive human intervention including vaccination and quarantine the wildebeest population has been transformed. The Serengeti and Maasai Mara have been magnificently rewilded and the population of these animals is back to a stable 1.5 M with no disease detected in the last 8 years. Perhaps my 30 year wait to go was helpful because it allowed the wilderness more time to recover.

View to the south where the spread of animals seems endless.
Mixed wildebeest with zebra was a common observation
Animals on the move for the last hour and will probably continue for the next hour (My first video)

The sight of all these animals and the resource to feed and accommodate all of them provides a small but expanding view of the might of the ecosystem. At one time in the distant past this view would have been quite prosaic. Imagine Neanderthal or possibly the older Cro-Magnon people living with this type of annual migration. They would have been part of it. They would have been much earlier than our current view of history, but it probably looked like the American Great Basin to the First Peoples and early settlers of the Americas. We must appreciate that this area is just a few hundreds of miles from the Olduvei (Oldupai) gorge where Lewis and Mary Leakey (beginning in 1937) found fossilized hominoid remains dating back hundreds of thousands of years. (Pronconsul 25 million years old).  What were those people thinking when they saw this sight? The ancient hominoids and modern tribal peoples were and still are intimately connected with this environment. Their moment-to-moment survivals depended upon understanding this grand recipe and also the small, intimate details of their surroundings. The people of the Maasai tribe move their domesticated herds in synchrony with the wildlife, plants and rainfall. They know this because of their exposure to a multigenerational experience. They now participate in separation of their herds of domestic cattle and vaccination from Rinderpest and Foot and Mouth disease. We were so poorly prepared to comprehend systems as complex as this in just a few days.

I think that there are many lessons to be learned from this. For at least a million years hominoids and humans have learned that living in harmony with the constantly changing environment is a prerequisite to survival. The environment changes including geologic-like continental drift and volcanism. Weather changes, due to wind and rain/snow, land slides and floods, drought, temperature and storms. Species changes with mutations and natural selection. Human behavioral changes including perception and interpretation of surroundings, the value of group behavior and behavioral adaptation by creation of societies. Society changes with development of institutions like religion and governments. Behavior changes lead to exploration, discovery, invention and industrialization. The nomadic herders of today who live in near Stone Age conditions with cell phones will change. What changes will Space Age people make? We, the people of the space, information and atomic age have the ability to affect all of the aforementioned changes. We have the opportunity to do so because we live with disposable wealth and a discretionally directed time.

From the successful story of the rewilding of wildebeests in the Serengeti we have started on a new path. The wildebeest story is considered one of the most successful rewildings of our time. Rewilding efforts have been remarkably successful in Yellowstone, Spain, Argentina, Switzerland, ocean reef areas and many more. These efforts can not only save species and restore habitats but also fight the climate change crisis. Rewinding Florida is an active effort and a topic worthy of further exploration and discussion.

#Africa #wildebeest #Great Migration #migration #Maasai Mara. #Serengeti #rewilding #Mara river #stampede

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Geography – Okavango Delta and Maasai Mara Savanna

UNDERSTANDING THE TWO ECOLOGICAL SYSTEMS BY COMPARING THEM FROM THE GROUND UP.

To help understand what is happening in this system it may be made easier by look at its parts. There may be some errors in this method but at least this is a reasonable hypothetical start. Let’s begin with the idea that every detail is important and that everything is interconnected. Also, if a part of the system is lost the entire system is compromised. See the map at the end of this posting.

The featured image shows one of thousands of termite colony mounds

The Okavango and Mara locations are very different not only in location and elevation but also in geology. Two soil samples were taken from typical road side areas in the savannah-like landscapes away from human traffic areas. Under the microscope you can see that the individual sand grains are transparent, something which is not obvious when looking at the sand with the unaided eye. The sand of the Delta (Fig. A1 & 2 is made up mostly of silicon dioxide (SiO2). It is completely glassy. It is not soluble and has no mineral content. Volcanic pumice Fig B1 & 2 is a complex particle aggregate of ash feldspar. It is an incomplete glass with other minerals at the particles’ surfaces. The Mara soil has a much higher metabolizable mineral content which makes the soil more fertile than the Delta.

Fig A1. Sand particle sample from Okavango Delta. (20X) Completely translucent. Illuminated with transmitted plane light. This is nearly pure silica.
Fig. A2. Sand particle sample from Okavango Delta. (20X)
Completely translucent. Illuminated with transmitted polarized light.
Fig.B1
Sand particle sample from Mara.
Note the surface’s complex micro-porosity. Illuminated in dark field with direct lighting. This amorphous, opaque particle is definitely volcanic in origin. (20X)
Fig. B2.
Sand particle sample from Mara. (20X) Completely opaque. The red color is iron oxide. Illuminated in dark field with direct lighting.

—+—-

OKOVANGO DELTA

The Delta is flat but it is cyclically flooded and the colors are green and tan. The islands of the Delta were built by the humblest of creatures. The termites as architects, engineers and builders have created a landscape of unbelievable variety. They harvest the dead plants and with the sand of the Kalahari desert and they build massive, nearly indestructible castles reaching meters into the sky. The nest height is determined by the water level. The higher the water level, the taller the nest will be. When the population reaches a critical mass, a new colony is initiated. With erosion by water, wind, and the burrowing of animals the mounds collapse and islands grow. As a result of centuries of this cycle the islands provide a collective of soil used by the large mammals, birds and fish. The aquatic plants are supplemented by grasses, brush, bushes, and trees. These form savannas in the Delta for non-migrating herds of grazing land animals and the creatures which accompany them. They also encourage aquatic animals like fish, birds, reptiles, and mammals which are supported by the aquatic environment. 

Termite mound on savannah island of the Okavango Delta
Pampa Grass (Niscanthus junceus) Assists in forming islands by trapping sand and with decaying plants supports rooted water plants such as water lillies.
Blue Water Lilly (Nymphea nouchali). These also assist in the formation of islands and support protective areas for aquatic animals.
Marshland in the Okavango Delta with grazing zebras. The trees in the background are on the island that emerged from the work of the termites and plants.
Impala roaming through of the woodlands of the Okavango Delta. This land is based on the foundation of sand deposited by wind and water sediment which is fixed and enriched by termites and plants.
These zebras are grazing on a very large island in the Okavango Delta. It appears like a classic savannah landscape.
Tree covered island succumbing to salt accumulation in the Okavango. The islands dehydrate and accumulate salt at the periphery. When high water returns and infiltrates the interior of the island the salt enters the soil. Plants, weakened by drought, are further dehydrated and die.

The water levels rise and fall because of the flow of several rivers that end in the Delta. The water never reaches the sea; hence the Delta. Water is lost by evaporation and transpiration. The animals have a reliable supply of water and plants. They do not migrate.

—-+—-

MAASAI MARA

The Kenyan savannah is so starkly different from the Okavango Delta they seem worlds apart. The Serengeti plane colors are tan and beige. The Mara land is flat and dry. In contrast to the Delta, the Maasai Mara is the result of volcanism and rain.  Dominating the landscape is the ancient volcano of Mt. Kenya along with the range of uplands that are a result of the enormous energy expended in tectonic plate collision and the spread of the great Rift Valley. It stands as a plateau at an elevation of about 1,480 to 2,280 meters. The volcanoes of the area have created a mineral rich soil which when watered by the seasonal rain provides an opportunity for lush grass to grow. There are few trees growing on the savanna of the Mara making it seem like a great lake of soil dressed in golden grass. The Mara also has riverine forests. The seasonal rains are predictably distributed regionally causing the rotation of the animal migration. The people of the Maasai tribe move their domesticated herds in synchrony with the wildlife, plants and rainfall. 

When looking at the landscape of the Maasai Mara it is nearly unavoidable to escape the surrounding mountains replete with volcanoes. Mount Kenya (ancient volcano) is just to the right side of the image. The ash of these are the source of the soil. The sand particles seen in Figs. B1&2 came from these volcanoes. Note how dry it is in this region.
Mara river cutting through the savannah. The river is a limited but reliable source of water. Seasonal rain is the major water resource however it is variable and recently very deminished.
Hillsides erosion adds to the plane.
The massive savannah of the Serengeti plane supports an animal migration that may be the greatest seasonal movement of animals on earth. The grass is lush and green.
Mount Kenya off in the distance as part of the Great Rift Valley. No migratory animals here.
This map* of the central eastern sextant of the continent of Africa shows the relative position of the two areas of our grand safari.

These two systems are much more complex than this simple description. This only becomes apparent after returning from there, collecting and organizing observations, and reflecting on the diversity and life forms and cycles. This leads to many more questions such as: Where did the glassy sand come from? Why do the two areas share so many identical species? Why are there so few cactus or pine species? How would you summarize the comparison of these two areas? Perhaps these questions can stimulate discussion in our comment section.

* Modified from African Safari Planning Map, 3rd ed. African Adventure Company 2018

#Kenya #Botswana #termite #savannah #sand #Kalahari #desert #map #Africa #great rift valley #Serengeti #Mara #Okavango #woods #marsh #zebra #impalla #great migration

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Wild Africa – A Trip In the Plan for 30 Years

An overview:

The previous posting on Africa showed the photographic preparation for the trip. This posting is an introduction to the upcoming blogs which will feature the animal and plant wildlife in more detail. This photo safari was planned for thirty years. It has been postponed three times. At last, this was the opportunity to go. Botswana and Kenya are the two countries we visited in sub-Saharan Africa. The reasons to go there were their diversity of wildlife, ecosystems, and safety. The month of August was selected to be timely to see the greatest density of animals in the most clement season. It was also an opportunity to look for the similarities and differences of the comparable African and US locations. Here are thoughts, impressions and recounting of the two weeks of experience there.

The title sunset image is typical of the African sky. The beautiful sunset red comes from sand and minerals of the desert suspended in the air and refracted by the light. These same sands which are blown across the Atlantic Ocean color our Floridian sunsets too.

This lengthy monologue is only a rudimentary description of a very large subject. It is intended to help understand and appreciate the reasons for these features seen on this expedition and to summarize the complexities of the climate, geology, the flow of water on the land, the interdependency of species and some similarities to areas in the USA. The two major eco systems were marshlands and savanna. In Botswana the wetlands of the Okavango delta were the focal point. In Kenya the savanna of the Maasai Mara section of the Serengeti was of greatest interest. The Okavango delta ecosystem has some similarities to the wetlands found in the Southwest Florida Everglades National and State Park systems. The Maasai Mara is more like the grasslands of Montana where, 250 years ago, buffalo, antelope, elk, and wolf roamed in their own great migration.

Climate and Geology:

The Okavango delta is 19 degrees south of the Equator. The Florida Everglades are 19 degrees north of the equator. They receive approximately the same amount of energy from the sun. The marshlands of the Okavango delta and the Florida Everglades are both essentially inland dispersions of fresh water. The Okavango is a unique feature of the Kalahari Desert. This delta is deep in the interior of the land mass and the climate is continental. Unlike the Everglades, it does not have the moderating exposure to a neighboring ocean. It has a soil basis of sand that averages 200 feet deep. On top of that is a soil of a few inches depth with mixtures of soil brought by wind, flood, and a thin organic compost. The average elevation is 3100 ft. The delta has three biome types that include savanna, woodlands, and swamp. The Okavango River supply is derived from the confluence of the Cubango and Cuito rivers in Angola. The annual flow reaches the delta between March and June with maximum flow in July. Additionally, there is seasonal 18-inch rainfall in the Okavango from November to February which adds to water shed. 

Floridian Everglades are at sea level and are founded on petrified sea bottom called sedimentary rock with a high calcium carbonate basis called limestone. The Florida Everglades topsoil is an average 17-foot-thick layer of marl (calcitic mud), peat and muck. The Everglades are subtropical wetlands whose freshwater system begins near Orlando in the Kissimmee River. The average annual rainfall is 60 inches. The Everglades have a maritime weather with tropical storms and moderation of climate. Climatically, there are no hurricanes in the Okavango and in the Everglades there is no drought.

In support of the science of plate tectonics. The Americas and Africa were one land mass 200 million years ago.

The concept of moving plates of the crust of the earth suggests that at a distant time in the past the assembly of the plates separated into the various land bodies. The shapes of the land mass fragments seen today can be manipulated as puzzle pieces into a larger land mass that fits together quite well. This particular assembly is called Pangea. If this is how the continents formed then there is a strong relationship between the eastern geology of the Americas and the western African geology. This fit is not entirely perfect, however, when considering the length of time for the division to transpire it is remarkably good. This has been supported by substantial evidence of rock formations that span the continents.The science is based on continental fit, matching rocks, fossils, corals, mountains, glacial striations, magnetic lineages and direct measurement of the movement.

Plate tectonics

Comparison of ecosystems:

Water and Land:

About 98% of the water that goes into the Okavango delta is eventually lost through evaporation and transpiration.  Transpiration results when water moves through the plant and evaporates from leaves and flowers. Despite the subtropical sun generating intense evaporation, the delta’s water is fresh, not salty. I was surprised by this because non circulating ponds of water in the middle parts of the islands have very high chemical and salt concentrations. This chemical concentration occurs in thousands of islands. The reason the water is fresh is that trees on the edges of the islands create a barrier of natural filters between the inner part of the islands and the floodplain. The second reason is a process of transpiration caused by trees. Water flows into the delta and carries with it silica and soluble minerals like sodium carbonate. As the water is lost from the trees, the silica and salts remain to build islands. The center of the islands concentrates the accumulated salt and as a result the vegetation dies from dehydration leaving a central bare white mineral spot. Termites facilitate island formation when they build nests of organic material, fungus, soil and water. These mounds of soil and nutrients promote tree and other plant growth.  When the seasonal water rises the termites build skyward forming islands. Eventually the nest is abandoned to form a new colony. The mound then collapses from animal invasion and erosion. Termites are the keystone species of the Okavango. Without them the delta would be like the desert. Water would be lost, and life would be less dense and less diverse.The Okavango has no palm trees and pines are also nearly absent. 

Pond in center of a large island in the Okavango delta. Salt has accumulated in the water causing the trees to dehydrate and die.
Okavango Savana, for centuries built from sedimentation and termite mound building. Trees in the center of the island died from dehydration caused by salt accumulation. Grass is a monocot and is salt tolerant. The termites moved out and the mound is vacant.
Intermittently flooded lowland in the high water season of the Okavango delta
Freely flowing fresh water in a branch of the Okavango river. The plant is Pampas grass (Miscanthus juncos).

The vegetation in Florida also plays an important role. The ocean barrier to salt invasion are mangroves which are salt tolerant. These mangroves are key to prevention of back flow of the salty ocean and hold the soil preventing erosion. Some fresh water flow does reach the ocean creating a relative partial positive pressure. The soils of the Everglades are rich in nitrates and farmers increase the nitrogen of a large portion of the Everglades. This has resulted in an overgrowth of a complex of bacteria species which feeds on the nitrates and deplete the nutrient value of the topsoil. The Everglades have no Acacia trees and lots of mosquitos.

The Kenyan savanna is climatically and geologically very different from the Okavango savanna. Kenya is at the Equator. It is a mile high in altitude and the soil is volcanic in origin. It is more like the area around Denver CO. It is surrounded by hills and mountains and has two rivers flowing through it. The major river flow is the Mara. The other is the Talek. It is part of the Mara-Serengeti ecosystem spanning Tanzania and Kenya and has been geologically very active with ancient and recent rock formations. It is in the Great Rift Valley. It is in this valley that the million-year-old petrified remains of very early hominoids have been found. 

High planes savanna of the Maasai Mara portion of the Serengeti plane. Mt Kenya is on the right horizon.
River cut into the Mara plane providing water to the vegetation and wildlife. This is a spot where the Wildebeests would cross during their migration. They would climb the banks of the river during a stampede. The animals are subject to the risks of death from the crocodiles that ply the river during the crossing.
Igneous rock formation on exposed hill side in the western Mt Kenya highlands.

The plants and animals are widely different in speciation in these three areas but they have similar behavior. This may be the result of adaptation to similar geologic and weather conditions. The apex predators of all locations are big cats. All have eagles, egrets, large carnivorous reptiles and cats and lots of grass.

Human impact:

The effect of the behavior of large numbers of modern people on the Florida ecosystem is dramatically different from the African locations. The Everglades water flow is highly engineered and not necessarily for the best. Southward flow of the Florida delta is interfered by highways and farms to the point that it does not meet the sea as it original did. The Okavango delta also does not meet the sea. In Africa the observed locations have relatively low populations and have been benignly neglected or protected from hunting, industrialization, mining or drilling and farming so that the plants and animals have survived basically unchanged for centuries or even millennia.

Romancing Wild Africa:

We went to see the animal life of Africa and did not go to see the cities, towns, or villages. We did not have much contact with the people of the areas we visited. Africa is a huge, populous, resource rich continent with a history that dates to the origin of most species. There is great wealth and great poverty. Too many people have nothing. They live an impoverished stone age existence in the space age. I acknowledge that many of these are desperately poor and politically persecuted to enslavement and/or death. The NGOs, like CARE, work to help many but must be careful to manage their limited resources. They also try not to support the migrant people in camps to a better level than the local people. The native residents also live by subsistence on gardening, raising a few cattle, contract farm working, tourism, and crafts. Some also engage in a variety of illegal endeavors such as poaching and grazing their animals on park land. You can read the newspapers for details of other antisocial behaviors such as intertribal warfare, abduction, extortion, theft, civil insurrection etc. Desperate people do desperate things.

The wilderness of the savanna of Africa is nothing like anything in eastern US. There is no sense of luxury to the plants or the soil. Much of the topsoil is sand deposited by wind and water. The stark beige color varies little by the source of volcanic mineralization. The organic content is not a rich loam of plant breakdown. It is thin and the organic content is from the sparse droppings from animals or the occasional bush or more rarely from a tree. Animal droppings are recycled by the life on the planes and provide an episodic line of trees from incompletely digested seeds. The brilliant emerald green plants, startling blue sky and the breathtaking color of twilight is such a relief from the monotony.

Next:

We will look in greater detail at the findings of this two-week photo expedition in the following blogs. They will focus more on species than locations. 

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#Africa #Okavango #Botswana #Kenya #Everglades #transpiration #Maasai Mara #salt #tectonics #transpiration #evaporation #Tanzania #marsh land #savanna

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