Wednesday, October 21, 2009
Tuesday, October 6, 2009
Monday, September 28, 2009
At home amongst bushbabies
When I’m at home (which is not too often), I live in a bushbaby sanctuary which remarkably is located in the middle of the city. The developers of this townhouse complex rose to the challenge of incorporating wildlife into city living. Having identified the site, it was discovered that a naturally occurring population of lesser bushbabies (Galago maholi) were already in residence there. Instead of merely flattening the area for construction, the bushbabies were taken into ‘protective custody’ for the duration of building and sections of the natural bush preserved for their release back into their habitat once construction was complete. Subsequently gardens were planted comprising only indigenous vegetation including transplanted trees of the variety crucial for the survival of the VIP residents and these are connected via the residents’ gardens by ropes along which the small primates scamper like tight-rope walkers each evening on their way to feed.
Bushbabies are amazingly adapted for their nocturnal, arboreal lifestyles. They have enormous eyes with expanding pupils that allow for the collection of light in poor light conditions. Their eyes are so large that they are immovable in their sockets and to compensate bushbabies can rotate their heads 180 degrees (much like a bird) to look over their shoulders. They are able to bulge their eyeballs to gain focus of an object. There is a highly reflective layer called the tapetum lucidum in the back of the eye which shines reddish in torchlight. This also facilitates night time vision. Remarkably for nocturnal creatures, bushbabies have a high percentage of colour cone cells on the retina.
Bushbabies have long whiskers (vibrissae) near the eyes to help them detect nearby objects and so protect the eyes while foraging in the dark. The membranous ears are also moveable and can be swivelled independently or simultaneously to pick up sounds or can be folded back out of harms way. Bushbabies’ hearing is so acute that they are able to locate insects on sound alone even snapping gnats out of the air with their hands. They in fact jump upon prey with their eyes closed so as not to get flailing insect parts in them.
The bushbabies brilliant leaping ability is effected by enlarged powerful hind legs and the long tail is used for power and balance. Primate-like hands and feet with nailed fingers and dexterous thumbs and toes assist with grip. The ends of the digits are padded with soft friction pads as well as the palm of the hands and the soles of the feet. These also help with grip and with capturing prey. They are able to land and grip with just their feet to keep their hands free for grasping prey. Bushbabies can leap horizontally up to 4m and vertically almost 2m. They can cover many meters (ten yards) in just a few seconds and more than a kilometre in a night with these impressive leaps and bounds. On the ground, bushbabies hop like miniature kangaroos. They have taken to doing this along the perimeter walls if roping across the garden becomes too mundane!
Bushbabies are amazingly adapted for their nocturnal, arboreal lifestyles. They have enormous eyes with expanding pupils that allow for the collection of light in poor light conditions. Their eyes are so large that they are immovable in their sockets and to compensate bushbabies can rotate their heads 180 degrees (much like a bird) to look over their shoulders. They are able to bulge their eyeballs to gain focus of an object. There is a highly reflective layer called the tapetum lucidum in the back of the eye which shines reddish in torchlight. This also facilitates night time vision. Remarkably for nocturnal creatures, bushbabies have a high percentage of colour cone cells on the retina.
Bushbabies have long whiskers (vibrissae) near the eyes to help them detect nearby objects and so protect the eyes while foraging in the dark. The membranous ears are also moveable and can be swivelled independently or simultaneously to pick up sounds or can be folded back out of harms way. Bushbabies’ hearing is so acute that they are able to locate insects on sound alone even snapping gnats out of the air with their hands. They in fact jump upon prey with their eyes closed so as not to get flailing insect parts in them.
The bushbabies brilliant leaping ability is effected by enlarged powerful hind legs and the long tail is used for power and balance. Primate-like hands and feet with nailed fingers and dexterous thumbs and toes assist with grip. The ends of the digits are padded with soft friction pads as well as the palm of the hands and the soles of the feet. These also help with grip and with capturing prey. They are able to land and grip with just their feet to keep their hands free for grasping prey. Bushbabies can leap horizontally up to 4m and vertically almost 2m. They can cover many meters (ten yards) in just a few seconds and more than a kilometre in a night with these impressive leaps and bounds. On the ground, bushbabies hop like miniature kangaroos. They have taken to doing this along the perimeter walls if roping across the garden becomes too mundane!
Friday, September 11, 2009
Chasing Cheetah
The Masai Mara is a predator haven few places can rival. The other night we headed off to walk the dogs on a private airstrip only to discover the area to be occupied by a female cheetah and her three tiny cubs. The clever mother had killed a rather large Grant ’s gazelle as supper for her brood and was blissfully oblivious to the fact that two eager hounds were now not going to get their evening walk.
We were delighted. The Olare Orok Conservancy is testament to the fact that there are solutions to Africa (and specifically Kenya’s) wildlife-human challenges. The area is community owned land that abuts the Masai Mara National Reserve and as a result of an official agreement between the community and various tourism partners, the Masai people have moved their settlements and livestock off the land to accommodate for unspoilt wildlife and eco-tourism and each family reaps a direct monthly monetary reward in return. Although land ownership is new (and somewhat foreign) for the Masai, this arrangement is suiting both parties well and the conservation of wildlife is the direct result and overtly obvious. The Olare Orok Conservancy is a paradise teaming with game. See www.oocmara.com to learn more.
Cheetah are predators specialized for speed. Clocking a record speed of 112 kmph, they are undoubtedly the fastest land mammals. Generally cheetah only accelerate up to between 75-100kmph at a full sprint and this lasts only a few hundred meters before they tire. In order to be successful, cheetah must get close enough to their quarry before embarking on the final sprint and are thus accomplished stalkers. They hunt in open areas making use of any available cover to stalk or they may simply walk directly towards the prey freezing immediately should the animal raise its head. Cheetah will try to get within 100m of their target before chasing it and they typically choose animals isolated on the skirt of a herd. Once the chase is underway, cheetah will pursue the animal for a short time only and its marvellous sprinting ability must enable it to gain on the prey almost immediately in order to trip it up with a paw and then secure a throat grip (thus depriving the prey of already depleted oxygen reserves) or else the cheetah will abandon the chase.
Once a kill is made, the cheetah is too exhausted to feed immediately and rests to catch its breath first. Prey is eaten where it falls or dragged to nearby shade if possible. Cheetah are picky eaters skimming meat neatly off the surface of a carcass. They may eat the heart and liver but the other innards are discarded. Bones and skin are also discarded due to their toughness and the cheetah’s diminished dentition and small jaws. They only scavenge occasionally and usually when displacing another predator is not required. Although cheetahs are relatively large in size, they generally do not attack large ungulates (hoofed animals) like wildebeest, zebra or buffalo. This is due to the fact that pulling these powerful animals down requires great strength which the cheetah lacks and in the process would risk injury to itself. Coalitions of males may cooperate to pull down larger prey but usually they target younger animals of these species.
Because cheetah are so over-specialized for speed they are almost totally defenseless against larger predators like lion, leopard, hyena and even vultures. As a result they are very susceptible to loosing kills to larger predators. To avoid the attentions of largely nocturnal carnivores, cheetah hunt during the day (diurnal predators). However, all predators are opportunistic and should they become aware of a kill, they will scavenge regardless of the time of day.
Cheetah specialization includes the following: They have long legs, long, flexible spines and wasp-like waists that in combination effect the long strides necessary to run quickly. The chest of the cheetah is deep set to accommodate its large lungs and heart, the internal powerhouse of the sprinter. The tail is long and acts as a rudder to counter-balance the cheetah when it has to change direction quickly. The head is small and stream-lined with only small ears. The teeth are smaller than other similar sized predators as these make the skull heavy. The reduced dentition also makes room for bigger nasal cavities to improve oxygen intake while in full sprint and to facilitate breathing when suffocating captured prey. Cheetah also have aerodynamic nostrils to maximize the flow of air over them while running. Although it is commonly thought that cheetah can’t ‘retract’ their claws at all, they do in fact have semi-retractable claws but these are unsheathed and so appear to be permanently protruding. This is an adaptation to assist with traction during chases. Pads on the underside of the feet are hard and often ridged which also assists with traction and improves their braking ability.
Cheetah are considered attentive mothers and cubs, which are born in tall grass or other cleverly hidden sites after just three months gestation, will regularly be moved to remain undetected and free of parasite infestations. The female painstakingly moves her cubs one at a time pinching them by the scruff of the neck which relaxes the nerves in that area and calms the cubs as they travel. The female brings meat back to her litter when they are still as young as five weeks old and in just three months the cubs are completely weaned and by eight months old will begin to hunt and make their own kills.
Young cheetah cubs (up to three months old) have a mantle of grey fur along the saddle of their backs which at quick glance resembles the colouration of the formidable honey badger. This mimicry is believed to deter larger predators from attacking the defenceless cubs as they are mistaken by predators for the more ferocious and generally avoided badger.
We were delighted. The Olare Orok Conservancy is testament to the fact that there are solutions to Africa (and specifically Kenya’s) wildlife-human challenges. The area is community owned land that abuts the Masai Mara National Reserve and as a result of an official agreement between the community and various tourism partners, the Masai people have moved their settlements and livestock off the land to accommodate for unspoilt wildlife and eco-tourism and each family reaps a direct monthly monetary reward in return. Although land ownership is new (and somewhat foreign) for the Masai, this arrangement is suiting both parties well and the conservation of wildlife is the direct result and overtly obvious. The Olare Orok Conservancy is a paradise teaming with game. See www.oocmara.com to learn more.
Cheetah are predators specialized for speed. Clocking a record speed of 112 kmph, they are undoubtedly the fastest land mammals. Generally cheetah only accelerate up to between 75-100kmph at a full sprint and this lasts only a few hundred meters before they tire. In order to be successful, cheetah must get close enough to their quarry before embarking on the final sprint and are thus accomplished stalkers. They hunt in open areas making use of any available cover to stalk or they may simply walk directly towards the prey freezing immediately should the animal raise its head. Cheetah will try to get within 100m of their target before chasing it and they typically choose animals isolated on the skirt of a herd. Once the chase is underway, cheetah will pursue the animal for a short time only and its marvellous sprinting ability must enable it to gain on the prey almost immediately in order to trip it up with a paw and then secure a throat grip (thus depriving the prey of already depleted oxygen reserves) or else the cheetah will abandon the chase.
Once a kill is made, the cheetah is too exhausted to feed immediately and rests to catch its breath first. Prey is eaten where it falls or dragged to nearby shade if possible. Cheetah are picky eaters skimming meat neatly off the surface of a carcass. They may eat the heart and liver but the other innards are discarded. Bones and skin are also discarded due to their toughness and the cheetah’s diminished dentition and small jaws. They only scavenge occasionally and usually when displacing another predator is not required. Although cheetahs are relatively large in size, they generally do not attack large ungulates (hoofed animals) like wildebeest, zebra or buffalo. This is due to the fact that pulling these powerful animals down requires great strength which the cheetah lacks and in the process would risk injury to itself. Coalitions of males may cooperate to pull down larger prey but usually they target younger animals of these species.
Because cheetah are so over-specialized for speed they are almost totally defenseless against larger predators like lion, leopard, hyena and even vultures. As a result they are very susceptible to loosing kills to larger predators. To avoid the attentions of largely nocturnal carnivores, cheetah hunt during the day (diurnal predators). However, all predators are opportunistic and should they become aware of a kill, they will scavenge regardless of the time of day.
Cheetah specialization includes the following: They have long legs, long, flexible spines and wasp-like waists that in combination effect the long strides necessary to run quickly. The chest of the cheetah is deep set to accommodate its large lungs and heart, the internal powerhouse of the sprinter. The tail is long and acts as a rudder to counter-balance the cheetah when it has to change direction quickly. The head is small and stream-lined with only small ears. The teeth are smaller than other similar sized predators as these make the skull heavy. The reduced dentition also makes room for bigger nasal cavities to improve oxygen intake while in full sprint and to facilitate breathing when suffocating captured prey. Cheetah also have aerodynamic nostrils to maximize the flow of air over them while running. Although it is commonly thought that cheetah can’t ‘retract’ their claws at all, they do in fact have semi-retractable claws but these are unsheathed and so appear to be permanently protruding. This is an adaptation to assist with traction during chases. Pads on the underside of the feet are hard and often ridged which also assists with traction and improves their braking ability.
Cheetah are considered attentive mothers and cubs, which are born in tall grass or other cleverly hidden sites after just three months gestation, will regularly be moved to remain undetected and free of parasite infestations. The female painstakingly moves her cubs one at a time pinching them by the scruff of the neck which relaxes the nerves in that area and calms the cubs as they travel. The female brings meat back to her litter when they are still as young as five weeks old and in just three months the cubs are completely weaned and by eight months old will begin to hunt and make their own kills.
Young cheetah cubs (up to three months old) have a mantle of grey fur along the saddle of their backs which at quick glance resembles the colouration of the formidable honey badger. This mimicry is believed to deter larger predators from attacking the defenceless cubs as they are mistaken by predators for the more ferocious and generally avoided badger.
Tuesday, September 8, 2009
Enjoy every sunset
It doesn't matter how many I've seen, every sunset in the bush seems to take my breath away. When you're working and you have to travel across miles of wilderness just to get from A to B to do whatever it is you need to do, its such an incredible priveledge to be able to enjoy the wonders that nature throws at you along the way. It takes a couple of moments to stop and just appreciate it and breathe deep before carrying on with the task at hand. Thats why I do this job!Monday, August 31, 2009
Luangwa - Battlefield of Hippo (Part 5)
Although they all but share a kingdom, both the crocodiles and the hippos are prepared to cross boundaries if something is at stake. For the crocodiles it’s a matter of food, for the hippos, possibly a matter of kinship or simply a lack of cognitive understanding of death. Amidst the feeding chaos, the hippo’s own brave the hordes of shiny teeth and flailing tempers for an investigation. Barging through the ranks of crocodiles, biting, pushing…what are the rules?
Recognition is sought by the hippo through licks and sniffs and nudges. The opening of the mouth indicates the use of the vemoronasal organ (commonly called the Organ of Jacobsen) which detects airborne steroid hormones. Typically this organ is used in determining whether an individual is ready to mate but is also used in the recognition of individuals. Maybe the salts on the sun-baked skin are simply a dry season delicacy for those who survive to harvest it? The teeth of a hippo are not exactly designed to nibble meat off spongy carcasses but licking is certainly possible. Hippos are after all the descendents of pigs.
On a particular channel, the Changwa, there are so many hippos packed together in the shallow remaining water of a fast shrinking river that a photograph reveals 100 heads but no light or space between them…it’s an epic tin of sardines! Changwa especially becomes overcrowded as the water level drops, a giant super-pod of thriving bodies and bad tempers. The rerouting of the river here, in its relentless quest to change course and create oxbows, provided an apparently super-attractive spot of hippo real estate. The Changwa Pod is no ordinary pod of hippos, it’s a super-pod and they offer us an exaggerated look at the dynamics of hippo life in the Valley. Fights break out…disease attacks…heat exhaustion takes its toll and hippos die creating a feast of notable proportions for the 100’s of crocs in the river that pile into these carcasses in numbers up to 200 at a time. The crux comes when the lions find such carcasses on the waters edge and fight off the crocs in a unique predator standoff for sole access to the meat.
For most of the year, these species seldom clash. Lions dispatch all decaying finds on land, crocodiles keep the Luangwa’s waters clean. Not so at this time of year. It’s a free for all and a wealth of hippo meat is too good a find for both competitors and sharing is just not an option. Armed with enormous teeth, lightning fast reflexes and claws of steel, the crocodile is a force to be reckoned with. But although the crocodile is obstinate and has craftiness on its side, there is a chink in its armour. Ten times the size of a lions’ jaws perhaps, the crocodile’s jaws do not provide an enormous amount of crushing power. Success is in the surprise of the attack and thereafter the ability to latch, drown and twist to feed off their prey. If matched against the lions and hippo, the crocs are up against high odds when out of their own domain.
Moving straight in, the lioness drags the carcass inch at a time up the beach, gaining ground for the lions before the carcass is lightened enough to be fleet-footed into the water. The water means victory for the crocodiles and here the lions do fear to tread! The crocodiles crawl up the beach after their escaping meal. The lions have speed and muscular power on land but the crocs have overpowering numbers on their side.
The Luangwa Valley’s top predators come face to face in the ultimate showdown. Lions and crocodiles clash over the final rights to this ultimate dry season prize – a prize defended valiantly by its own kind!
Wednesday, August 26, 2009
Luangwa: Battlefield of Hippo (Part 4)
Nature’s abundance of sausage trees provides for Luangwa’s abundance of hippo and in turn this supports another abundance…
In the Luangwa, a profusion of Nile crocodiles infests the waters, feeding stealthily on fish, thirsty antelope compelled into the murky shallows and even the occasional unsuspecting fisherman – crocodiles are notoriously indiscriminate in their choice of victim. But it is the giants of the river, the hippos that sustain and replenish the hordes through the dry season. With so many hippo conflicting, large mounds of decaying meat are a common sight along the river during the dry months. The heat rots the flesh quickly and it doesn’t take long for the crocodiles to sense the feast. So acute are their smelling senses for navigating through the murky water that no free meal goes unnoticed. Poking top-mounted beady eyes above the surface of the water, the sight of the mound of decaying flesh confirms what the nostrils already detect and draws the crocodiles in their hordes...in their hundreds.
Sometimes boundaries must be crossed to access the meat…the crocodiles must move onto the land. Disarmed of their usual feeding format, the characteristic grip, spin and rip, the crocodiles can only enter the carcass where it is soft. The exceptional heat quickly loosens the flesh however and with some spectacular land-bound spins, the meat comes free - enough to lighten the load sufficiently after a day or two that they can drag the bulk into the water and there feast more comfortably in their own medium. Until then they pile upon one another, crudely slithering over each other like maggots.
In the Luangwa, a profusion of Nile crocodiles infests the waters, feeding stealthily on fish, thirsty antelope compelled into the murky shallows and even the occasional unsuspecting fisherman – crocodiles are notoriously indiscriminate in their choice of victim. But it is the giants of the river, the hippos that sustain and replenish the hordes through the dry season. With so many hippo conflicting, large mounds of decaying meat are a common sight along the river during the dry months. The heat rots the flesh quickly and it doesn’t take long for the crocodiles to sense the feast. So acute are their smelling senses for navigating through the murky water that no free meal goes unnoticed. Poking top-mounted beady eyes above the surface of the water, the sight of the mound of decaying flesh confirms what the nostrils already detect and draws the crocodiles in their hordes...in their hundreds.
Sometimes boundaries must be crossed to access the meat…the crocodiles must move onto the land. Disarmed of their usual feeding format, the characteristic grip, spin and rip, the crocodiles can only enter the carcass where it is soft. The exceptional heat quickly loosens the flesh however and with some spectacular land-bound spins, the meat comes free - enough to lighten the load sufficiently after a day or two that they can drag the bulk into the water and there feast more comfortably in their own medium. Until then they pile upon one another, crudely slithering over each other like maggots.
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