The golden hues of winter have brushed over the landscapes around the Concession. Each afternoon, as the sun begins to set, the sky is painted in vibrant tones of orange, red, pink, and blue.
As the abundance of water slowly starts to evaporate away, the movements of many of our Concession’s residents are slowly starting to become far more predictable. In particular, our big cat residents have once again taken to their habitual water sources on an almost-daily basis. As a result, not only has the frequency of sightings increased significantly but also, each safari has produced a visual spectacle of the magic of the African Bush.
In our May Newsletter, we will update you on what our favorite residents have been up to, and we will also dive into the fascinating topics of species competition as well as the evolutionary transition of species from water to land.
ECOLOGY: SPECIES INTERACTIONS AND COMPETITION
Organisms live within an ecological community, which is defined as an assemblage of populations of at least two different species that interact directly or indirectly within a defined geographical area. Species interactions form the basis for many ecosystem properties and processes that are essential for biodiversities such as nutrient cycles and food webs.
At the broadest level, ecological interactions can be defined as either intraspecific or interspecific. What does this mean? Intraspecific interactions: those that occur between individuals of the same species. Inter–specific interactions: those that occur between two or more species.
Let’s take a closer look at the ecological meaning of competition. This is most typically considered to be the interaction of individuals that compete over a common resource that is in limited supply. More generally, competition the direct or indirect interaction of organisms that leads to a change in biological fitness (the success of the species in its environment) when the organisms compete for the same resource. The outcome usually has a negative effect on the weaker of the two species (which most likely results in the weaker species being less successful in that environment). There are three major forms of competition: a) interference competition, b) exploitative competition, and c) apparent competition. We will investigate each form separately:
This is probably the most straightforward type of intraspecific competition to understand. In this form of competition, members of the same species “interfere” with one another when acquiring resources such as access to mating. In some cases, organisms that usually live communally will literally fight for resources, which can be seen in a basic troop of a baboon, for example. Normally, around 4 dominant males will run a troop, but one of them will prohibit any of the other males from accessing the mating females by using physical aggression or displays of aggression. Therefore, the more dominant male is directly altering the mating behavior of other males.
This occurs when individuals interact indirectly as they compete over common resources such as habitat, prey, or food. To put in more simple term, the use of the resource by one individual will decrease the amount of it available for other individuals. In the Kruger National Park, particularly, zebra and waterbuck (by virtue of their abundance and the success around watering holes) have outcompeted sable and roan antelope, which feed on the same types of grass. Another poignant example of this would be where the resources required by lions are limited by human activity, such as habitat loss due to expanding agriculture, human settlements, and the loss of wild prey.
This occurs when two individuals that do not directly compete for resources affect each other indirectly by being prey for the same predator. This type of competition occurs when the first group of species increases in number in a particular area. This, in turn, results in an increase in the number of predators in the area. For example, an increase in the number of buffalo in the Concession will cause an increase in the number of lions as they have a tendency to follow the large herds of buffalo. The increase in lion activity will therefore negatively affect other herbivores such as kudu and wildebeest, which are at greater risk of predation.
LIONS OF THE MLUWATI CONCESSION:
The month of May has seen no less than 9 fully grown adult males around the Concession. This has unfortunately resulted in many of our smaller female prides going into hiding. As both the Imbali and Hamiltons Pride currently have young cubs, it is likely that their sudden disappearance is a result of them protecting the young cubs from unknown males.
The Einstein Pride (Imbali Breakaways):
The Einstein Pride seems to have a new member! Einstein, the male after whom the Pride is named has been joined by a much younger male lion who has very little evidence of a mane at this stage. The two males were heard calling early one morning, and our guides managed to find the younger male first who eventually found Einstein. After somewhat of a standoff, where Einstein quickly established his dominance, sticking the younger male with a rather large paw and some very sharp nails, they moved off together.
The Hamiltons Pride:
Towards the end of the month, tracks for the Hamiltons Pride were found heading just outside of the Concession around the S125 Loop. On the same morning, Madala was found heading in the direction of these tracks. Based on the abundance of scavenging birds as well as birds of prey in the area, it is likely that the Pride managed to kill something substantial just outside of the Concession.
We were also very lucky to spent time with the four cubs of some of the lionesses who had left the adorable youngsters in the dense woodland just across the Camp as they went about hunting.
The four of them, though inquisitive of the vehicles, kept a safe distance and occupied themselves by playing around the muddy slopes and fallen tree logs of the area.
WILD DOGS OF THE MLUWATI CONCESSION:
Grab and Go. This is literally the way we have been encountering the Wild Dogs through the month. One running across the road leaving you still trying to figure out was went flying past you at a million miles an hour. Denning of the large pack is happening off concession but we are lucky enough after some burning done in the park that the dogs spend a lot of time on the concession looking for food to feed the hungry mouths of those back at the den. It will be great to see the little ones when they finally become active. Strange smaller group of dogs also spending a lot of time on the concession consisting of 3 adults only.
CHEETAH OF THE MLUWATI CONCESSION:
After a considerable absence, our favorite 4 boys are definitely back in town. It has been a month of stunning and unforgettable sightings of these incredible predators. Although they do still disappear for a few days back into Manyeleti and the Sabi Sand Wildtuin, we have been fortunate to spend some quality time with them throughout the month. A female cheetah has also been spotted every now again around Hamiltons Tented Camp. We are hoping that this female will have better luck this year producing a successful litter of cubs as the last cubs unfortunately did not make it.
ECOLOGY PART II: RESOURCES & COMPETITION
When we refer to resources this can include anything found in the environment that is necessary for growth and reproduction such as food, shelter, water, light and substrate or territory. For individuals of the same species this can also include mates. Resources can be different due to environmental conditions because resources have the potential to become scarce. Environmental conditions include components of the environment that affects the growth and reproduction of organisms but are shared identically among all members of an ecosystem. Such conditions include temperature, salinity and PH.
A major factor affecting the availability for resources in an ecosystem is the density of individuals, or the number of organisms living in a certain area. The more individuals live in a certain area the quicker the depletion of the resource will be which will also result in ecological competition for this now limited resource to intensify. Imbali Safari Lodge and Kruger National Park as a whole went through this experience during one of the severest droughts which continued through 2015 and 2016.
In order to simplify the intensity of ecological competition we can use the following example. If two different species of birds eat only one type of berry, competition for this berry will be intense. However, if out of the two species of birds one only eats a certain berry but the other is also know to eat local nuts or seeds then the competition for the berry will not be as great.
Russian Ecologist Georgii F Gause performed classic experiments in 1934 that led to the development of the competitive exclusion principal, also referred to as Gause’s law. He grew two species of closely related protozoans supplying them each with a controlled food source. When the two species were grown separately, they multiplied exponentially as predicted by theoretical equations of cell division. However, when the two species were grown together on the same food source only one species survived. The other species was eliminated. Gause’s competitive exclusion principle states that if a limiting resource exists in the environment and two species rely on that resource, only one species will survive. The other will become extinct in the environment or it will develop evolutionary adaptations that shift it toward a different ecological niche. Ecological competition affects the community structure of an ecosystem and it places evolutionary pressure of the development of adaptations in a population. As a result, changes to the competitive forces in an environment can not only affect the ecosystem as a whole, but also the evolutionary history of a species.
Within the vertebrates we see the evolution of increasingly complex fish, beginning with jawless fish. The jawless fish evolved to for, jawed, cartilaginous fish and eventually bony fish. Animals we commonly this of as vertebrates, four legged (or two legs or two wings) backboned animals, arose from bony fish. These tetrapod classes include the following: Amphibians, Birds, Reptiles, and Mammals.
LEOPARDS OF THE MLUWATI CONCESSION:
We have been blessed this month with so many leopard sightings and interactions, which have proved that our Concession is indeed a hive of leopard activity at the moment. All in all this month, we have probably seen leopard every 4/5 drives, which is definitely a record number of unforgettable sightings!
Our favourite leopardess was seen on numerous occasions around Hamiltons Tented Camp. On one very memorable occasion, she tried to steal some meat of an impala carcass from an unknown, skittish male who had left the carcass up in a marula tree. As soon as she began to make her way up the tree, the male emerged from the thickets and chased her off! Although very noisy, the interaction between the two never really resulted in any physical confrontations. Tiyasela also scent-marked repeatedly around the area. However, after a couple of days, the two leopards parted ways.
Wabayisa is still around and doing very well. He is currently spending a considerable amount of time around Imbali Safari Lodge. At the moment, he enjoys crossing into the lodge, choosing to walk through the drainage of our general manager’s house and continuing on past our boma until he makes his way back out of the lodge through the gate closer to Room 9. He also came across an younger male leopard on the open plains behind the staff village, which may explain why he is spending so much time around this area.
An unknown young female leopard was seen around the Imbali Staff Village and even climbed the marula tree in front of Julia’s house. It was the first time that we have ever seen a leopard climb this tree.
As mentioned above, we came across a young skittish male near Hamiltons Tented Camp. Over the course of the few days where he had his impala carcass up in the marula tree, he relaxed with the vehicles quite quickly. By the time he had finished the carcass, he was comfortable enough with our presence to voluntary lie down right next to the vehicle. He is a gorgeous leopard, and we certainly hope that he sticks around.
ECOLOGY PART III: FROM WATER TO LAND
A major evolutionary event that occurred within the vertebrates was the transition from water to land. This required a number of physiological changes to compensate for the differences between an aquatic environment and a terrestrial environment.
On land, animals need systems to conserve water, exchange gases internally and move from place to place on the ground. In addition, land animals cannot rely on water currents to disperse their gametes in order to sexually reproduce. These changes began to be seen as amphibians evolved from a bony fish called a lobe-finned fish. These fish had what are called proto-lungs and proto-limbs. The proto-lungs enabled them to surface from the water and breathe air for a short time. The proto-limbs, or lobed fins enabled them to walk out of the water and on land for short distances. From the lobe-finned fish, amphibians evolved true lungs and true limbs for survival on land. However, most amphibians are still dependent of water to lay their eggs.
Amphibian eggs are not able to survive in a non-aquatic environment because they do not have a waterproof covering – except for Foam Nest frogs who have developed even further by creating a protective layer covering the nest which hangs off branches over waterholes. The adaption first arose in reptiles, they have what is called an amniotic sac. In this sac the embryo is surrounded by layers of membranes and a solid, water impermeable shell. This allows the embryo to survive on dry land. Reptiles marked the full transition from water to land.
It is important to realize, however, that chordates were not the first animals to make the water to land transition. Arthropods had achieved this step independently and through evolutionary changes that were quite distinct from those of vertebrates. For example, arthropods dealt with the problem of retaining water partly by using a physical feature that they had already evolved, or pre-adapted, called the exoskeleton.
In the next newsletter we will go into some more interesting information about Mammals and Birds and how they managed to evolve through time and adapt to their ecological niches.
SCAVANGERS OF THE MLUWATI CONCESSION
Vulture Breeding on the Concession
It is that time of the year where white backed, hooded and white head vultures have returned to their nests from last season. Adjustments and the addition of some new sticks.
We are proud to boast a very healthy population of breeding sites here on the concession. Then newest nests found which is that of hooded vultures which is totally exciting.
Hyenas of the Mluwati Concession
It is surprizing to count the amount of times since April the Hoyo Hoyo clan have managed to catch and kill on Hoyo Hoyo main deck. It is incredible how quickly they have learnt how to actually herd animals onto the deck and into the corner by the dining room where they have learnt the antelope cannot escape from them. None of the actual kills have been seen while they are happening only the crime scene in the morning lets us know what has happened during the course of the midnight hours. Imbali clan have been on their own hunting missions but they are not as tenacious as Hoyo Hoyo so they steal from Leopard especially and very often groups of two or three hyenas will be seen following the wild dogs around know this is where they are going to be getting something to eat.
The Hamiltons clan seems to be spending most of their time in the eastern block – they have always been known to hunt for themselves.
FOOD FOR THOUGHT
There is a body of psychological theory that explores the biological benefits of immersing oneself in nature, particularly biophilia hypothesis and Attention Restoration Theory (ART). Biophilia hypothesis is described by psychologists as having an “an innate love for the natural world, universally felt by all, and resulting at least in part from our genetic make-up and evolutionary history”. Fundamentally, this hypothesis is based on the fact that our separation from nature (by the development of mass urban spaces) is relatively recent in the last 250 years, and that we have not yet adapted to this separation. As a result, we tend to experience increased levels of stress, anxiety, and impaired attention levels when not surrounded by nature.
Studies show that a prolonged exposure to nature improves our direct-attention abilities in the same way as how improving our nutrition and reducing the amount of choices increase our levels of mental willpower to problem-solve. The additional benefits of immersing oneself in nature include reduced levels of depression and anxiety, increased resilience, increased engagement in learning, improved self-esteem, increased physical health, and increased capacity to engage socially. Fundamentally, there is overwhelming scientific evidence that shows how nature is a vital actor in positive psychology—specifically in terms of our subjective levels of wellbeing, contentment and satisfaction, hope and optimism, as well as in our overall flow and happiness.
The more we immerse ourselves in nature, the greater levels of stress relief and willpower recovery we experience, which can then allow us to be more productive and to ultimately thrive!
“Nature holds the key to our aesthetic, intellectual, cognitive and even spiritual satisfaction…just being surrounded by bountiful nature, rejuvenates and inspires us” – Edward Osborne Wilson (on the Theory of Biophilia).
THE GUIDES OF THE MLUWATI CONCESSION