Interesting facts Bruce. We don’t realuze how big they really are.
On safari, giraffes are highly sought after. More so than leopards or lions. And to be honest, it does not surprise me how excited people are to see these magnificent creatures.
Here’s the truth: most of us who guide you on safari will have seen many giraffe in our respective lifetimes.
The giraffe, to most guides, is not like seeing the elusive leopard, for example. Many of my first-time safari guests, however, have placed the same importance and accompanying excitement on seeing their first giraffe just as they would any member of the Big 5. It is you guests who have re-instilled that awe inside me on viewing giraffe. You always give me the opportunity to see a giraffe for the ‘first time’ again, reminding me of how truly impressive and unique they are.
Having said that, giraffes are in fact categorised as vulnerable on the International Union for the Conservation of Nature (IUCN) species list. There are about 68, 000 giraffes in the wild.
Let’s get into some facts about them which you may not know…
Giraffes quite clearly have a heavy neck (over 600 pounds). You would think that it would be so cumbersome to keep its head and neck held up but the large muscular band in the neck holds up that huge combination of bone, muscle, tendon and blood without difficulty. In fact, the giraffe has more difficulty in bending its head down to the ground! The only times a giraffe will bend its head down (by pulling on that muscular band) is to drink and to pick up bones to chew (in order to increase certain minerals in its body like phosphorous).
On that note, it is essential for a giraffe to keep its head up. Firstly, it increases the chances of spotting lions (their main predator); it also links directly to their habit of not resting much during the day… giraffes will feed for about 18 hours in a day and sleep for only about 30-45 minutes. Isn’t that just crazy? Imagine sleeping for 45 minutes a day! The other hours are spent moving and wandering and ruminating as they find new trees to browse on. The males will also follow herds of females with an oestrus cow present (a female ready to mate).
Giraffes are really great indicators of predatory animals in an area. Look at the photograph above… see how all the giraffes are standing in a group extremely focused on and staring at the lions? Now imagine that we haven’t found the lions yet. You are half a mile away and you look up to the crest to see all of the giraffes behaving like this. You race around to see what they are looking at, and you find the lions! Giraffes won’t stare so intently on animals that aren’t predators. They’ll stare just like that when they see a leopard. And they’re so tall, making it easier to see them from a distance.
Giraffes have an incredible physiology. A giraffe’s heart is 11 kilograms (25 pounds) and over two feet long. This massive heart pumps 60 litres of blood around the body at twice the blood pressure of a human!
That’s a lot of blood; surely then when the giraffe bends down to drink the blood pressure around the brain will be too high? To protect the brain there are valves stopping the back flow of blood as well as blood vessels perfectly designed to contract and dilate to manage blood flow. There is also a network of capillaries in the brain that work like a sponge, absorbing the blood when the head is held below the neck.
As a runner myself, I am always interested in the heart rates of people and animals. Here’s a strange fact: the pygmy shrew, weighing less than an ounce, has a heart beat of 1,200 beats per minute (bpm)! Crazy, I know. Giraffes have a resting heart rate similar to humans, between 40-90 bpm. Think of how strong that heart is to pump so much blood around such a big body at such a low heart rate. Their hearts are also lopsided; the left ventricle has a much thicker wall (3.2 inches or 8 centimetres) than the right (0.6 inches or 1.5 centimetres) because the left side pumps blood up the two-meter neck whereas the right side pumps blood to the lungs.
Despite all the Wow! facts about giraffes, it only takes looking at their beautiful patterns, awkward gait, towering height and sheer size to be in awe of them. Even though I (and most likely your safari guide) have seen giraffes each year since I was born, I feel privileged to see them each time.
Filed under Wildlife
Hi Callum! Yes you’re right, the Nubian and Kordofan subspecies are most endangered. They’re listed as critically endangered.