Last week, spending time with the pack of wild dogs, while filming for the virtual safari, we had the privilege of witnessing the entire process of the adults venturing off on an afternoon hunt before returning to their pups. These formidable hunters successfully flushed, chased down, and caught a young male nyala. After gorging themselves at the carcass, the wild dogs dutifully returned to their pups, their bellies acting as temporary food storage units to safely transport some sustenance back to the young.
The insatiable appetite of the pups is temporarily subdued after the adults engage in a somewhat displeasing behaviour but one that is vital for these animals to survive. The adults regurgitate their quarry prompted by a begging response from the pups. This intriguing process sparked my curiosity, leading me to a deeper exploration of the intricacies of wild dog feeding strategy and their associated behavioural nuances.
While we take a moment to delve into some of the nitty-gritty of these fascinating animals and how they are probably the most successful hunters we will come across while on safari in Africa, let me just mention that individual feeding patterns and subsequent consequences are not fully understood and that I am merely shedding a bit of light on what I could find.
Wild dogs are purely carnivorous, deriving their energy from eating meat. Robyn discusses this process a little further here, if you are interested. But in a nutshell, they have a rapid digestive system that caters to their high energy demands of a rapid metabolic rate. Wild dogs could be described as highly collaborative endurance pursuit hunters whereby the pack can pursue their prey for kilometres. Once successful in catching the prey, they begin feeding, sometimes before the antelope has succumbed. Wild dogs live on what is known as an energetic knife edge, the energy costs of hunting are so high that should they lose a meal to another predator/scavenger such as a hyena and are unable to replenish their reserves, the impacts are enormous and they have to spend even longer hunting to achieve an energy balance.
How much energy do wild dogs burn in a day?
As one would imagine, the energy expenditure of wild dogs is exponentially greater than most other animals out here. For an animal that is seldomly seen walking and that chases its prey to exhausting at speeds of 60-70km/hr for 4-5km – it is no wonder that they need to eat at least once a day if not twice a day.
So trying to work out the daily energy expenditure of a wild dog would be beyond impossible, in fact, I wouldn’t even know where to begin. Thankfully, that’s where a little deep dive into the literature came to the rescue. I came across a study where the energy expenditure of six dogs was measured using the doubly labelled water technique, the average expenditure was 15.3 megajoules or 3670 calories per day. And the instantaneous cost of hunting was up to twenty-five times the basal metabolic rate.
OK, so I am sure that sounds like a bunch of gibberish to many of you, and in fact why does it even matter? Well, let me try to contextualise this while bearing in mind that this is almost like comparing apples with oranges. Anyway, energy expenditure or calories burnt is correlational to the size of the animal. The smaller and lighter you are, the easier it is to move around and the less energy is burnt in order to do so. Larger animals require more energy to move around.
I am a relatively active, 90kg (198lbs) individual who does at least one intense bout of exercise per day. My average daily calorie output was 2908 over the last week. Now compare that to the average calorie output of a wild dog, which weighs about one-third of my weight and yet still burns 3670 calories per day. So if we simply compare based on weight category taking the average weight of a wild dog to be 25kg, wild dogs would burn 13 212 calories a day if they weighed 90kgs. That is 4.5 times as many calories as I burn.
How much can wild dogs eat in a sitting?
Wild dogs are known for their remarkable hunting abilities and probably have the highest hunting success rate of all the large predators. However, since the energy expenditure of a hunting mission is so high, they need to ensure they can replenish their energy stores before the kleptoparasitic predators such as hyenas swoop in and steal a free meal. In this rapid quest to consume as much meat as possible from their freshly procured meal, they savagely tear mouthfuls off at a time, which are swallowed whole, with no time for chewing.
They can consume a significant amount of food for their size, but there is a limit to how much they can eat in a single sitting. This limit is determined by their stomach capacity, which varies among individuals. If the carcass is substantial enough, it is believed that each dog can consume between 1 kg and 6 kg of meat and some have a stomach capacity of up to 9 kg. That is more than a quarter of their own body weight.
Going off a rough estimate of about 120 calories per 100g of impala venison, at an average meal of say 4 kg, that is roughly 4800 calories. A surplus in the sense of replenishing what they would have burnt through the hunt and their basal metabolic rate. However, this figure would probably be less than that based on the wild dogs’ digestive system only absorbing 60-70% of what they eat.
So in consuming a slight excess of meat it allows for them to regurgitate for their young. However, the feeding behaviour of wild dogs is a complex and fascinating process. It’s not as structured as it might seem, with regurgitation being more of an instinctual response to the needs of the young pups rather than a precise portion control mechanism. The pack must strike a delicate balance between caring for their young and maintaining their strength for future hunts. This unique approach to parenting in the wild highlights the adaptability and resourcefulness of these remarkable animals.
Stay tuned for more on the actual regurgitation process…