For a very long time, it was believed that predators would not eat predators. This rule was probably first decided when people witnessed something like a lion killing a leopard and leaving the body unfed on. This may be the case in certain situations, but predators to often eat other predators. A bird of prey may feed on a snake, or a crocodile may grab an unsuspecting wild dog puppy, so it does certainly happen. We’re going to have a look at what predators feed on, why and how some have adapted to combat this.
Omnivores
There are many species of animals that do prey on other animals that will also feed on plant materials at certain times and these are known as omnivores. One of the most recognized omnivore in the world is the Grizzly and Black bears. We don’t have anything on that sort of scale in Africa, but our primates, jackals, certain mongoose species and civets are probably our best known.
Omnivores have a much higher metabolic rate than herbivores and normally prefer feeding on another animal than on plant materials. Plants do not have near as much protein, but need to be relied on at certain times when proteins in the form of prey can be hard to come by.
Important critters
It’s not only the mammals and birds that are important predators, but most of our reptiles, like crocodiles, lizards and snakes are also all predators. They themselves may be prey for other, larger species and often larger specimens of their own species. One of the biggest predators for young monitor lizards, is larger monitor lizards for example. All of these “smaller’ predators also manage to get into a lot of the smaller and inaccessible places the larger predators can’t. Also feeding on smaller prey that may be overlooked or not attempted by larger predators.
Large amounts of insects and all arachnids are predators. They feed on other invertebrates, birds and even small mammals at times. These predators are often then preyed on themselves by the larger predators as well.
Numbers and Energy
The fact that these smaller predators have a far greater prey availability to them, means that can survive in far higher numbers than the larger mammalian predators. If you have to compare the biomass of predatory insects to birds or mammals, or probably both even combined, the insects would far out way them. When it comes to producing, they seem to have much larger litters than the mammals or birds. Where an eagle may only have one chick survive, a snake may lay a clutch of more than forty eggs.
The fact that smaller predators have so much more food available to them, also means they are far more active and busy. Something like a wasp is always busy, resting occasionally, but easily picking up a fly or another insect as a snack. On the other side of the scale though you’ll have a lion that will rest for a large percentage of the day, conserving energy for an actual hunt. Many of the reptiles an energy saving, sitting in ambush, waiting for the prey to come to them. Others will rather forage over a large range which is far more energy demanding. Small insectivorous birds like warblers, will often use either of these two ideas.
Efficient digestion
Compared to the herbivores, the carnivores have a very efficient digestive system. Carnivore intestines usually measure out to be about the six times the length of the animals body, where a herbivore is almost twenty four time, this helps with their high carbohydrate diet. For the predator, little chewing is needed to eat the protein filled meat that is digested and turned back into energy very quickly. Herbivores are well adapted to their high carbohydrate diet and get enough from their vegetation and microorganisms. Predators get enough protein and produce carbs when necessary, using fats or amino acids.
Despite each having their pros and cons, the digestive tracts of both the predator and prey species are both incredibly evolved in their own right. Herbivores have a big advantage in the ways that is plentiful in good times and doesn’t move around like a herd of animals might for the big cats. These big predators may spend quite some time in the search and then hunt of their prey. Depending on group size and food availability, will depend on how large on area any species may need.
Birds
Birds of prey and other birds that feed on invertebrates, generally have a very similar body shape and size as have similar energy demands. Most of our birds of prey have strong hooked bills, phenomenal vision, powerful crushing talons and an acute sense of smell. Depending on the size of the bird, will depend on how much food the bird will need, which can be anything from 5% to 50% of its own mass. What we have found out is that the smaller birds need more food than the larger one. So a Lanner Falcon would need 50% of its own weight, where something like a White-backed Vulture only needs about 8%. The smaller birds need far more food to satisfy their energy requirements.
A lot of our insectivorous birds on the other hand, are a lot smaller in comparison to the birds of prey. These birds wouldn’t hunt from the air, but rather from a perch. Hunting insects that are very quick, means using a lot of energy and so they need to put a lot of energy. Some of these little birds eat as much as 60% of their own body weight in a day.
Protein is protein
With their specialized digestive system, the predators have managed to move wherever their prey species have moved. They are capable of finding and utilizing any protein that they could, even if it is one of their own. From the lions hunting the large herds of wildebeest, a snake catching a rodent or a prey mantis catching a moth, they are all predators.
