Conservation: The Little Five
Big Game hunting of the much-loved African ‘Big Five’ (the leopard, the rhino, the elephant, the buffalo and the lion) is fortunately far less popular these days than safaris to see them in natural environment, although the problem of poaching remains. South African Scientist Rael Loon felt that we should also get to know the ‘Little Five’ he identified in relation to these magnificent animals; entomologist Dr. Simon Carpenter takes us on a little safari to meet them.
No. 1 The Leopard Tortoise
The leopard tortoise is the second largest tortoise in Africa and is common across savannah and grassland habitats. The largest leopard tortoises still weigh in at 13-15kg. Despite this, and the not inconsiderable effort of carrying around their camouflaged shell, leopard tortoises are mobile and one frisky specimen was found to travel up to 8 km in a single day in the Nama-Karoo region of South Africa, although movement of around 100-200m each day is more common. Leopard tortoises do not burrow like many other tortoises, but tend to co-opt holes made by aardvarks and other medium-sized mammals.
Leopard tortoises are currently classified as being of low risk of extinction by the Convention on International Trade in Endangered Species (CITES), but were originally collected as part of the international pet trade. Captive-bred individuals are still popular in many countries, however, and can live for 75 years or longer, meaning that inheritance planning is a must for most prospective owners!
No. 2 The Rhinoceros Beetle
The spectacular rhinoceros beetles include some of the largest insects ever identified, reaching up to two inches in length, and are notable for possessing a spectacular range of horns in the case of males. This has made them popular subjects of research for evolutionary biologists interested in how animals select their mates.
In rhinoceros beetles there is evidence that males with large horns and body size are more successful in battle, but this is balanced by a greater chance of larger horns breaking. Larger males have also been found to be more prone to being spotted by crows and racoon dogs, for whom they are a great, protein-rich snack.
No. 3 The Elephant Shrew
Ostensibly the cutest of the little five, the elephant shrew (or Sengi) is bad news if you are a small invertebrate. While not strictly speaking a shrew, these mammals have the same compulsive attitude to food in order to maintain their metabolic rate and will happily consume worms, termites, beetles and centipedes.
Unlike shrews, they are active during the day which is made possible by their incredible speed. They do, however, occasionally fall prey to snakes, hawks and owls. Currently, 19 species of elephant shrew have been discovered, but they are restricted in range to Africa.
No. 4 The Buffalo Weaver
Another resident of the savannah, the buffalo weaver, is the easiest of the little five to see, but the least studied in terms of formal scientific research. All three birds get their names from a propensity to follow buffalo and collect insects they disturb. However, the degree to which this is a specific relationship is debatable, and the birds are far more likely to be encountered in their noisy colonies.
Red-bills have been suggested to be early adapters to environments disturbed by humans and livestock, with a survey finding that around 10% of their nests use man-made structures. This response may be important in surviving predicted future changes to the landscape of Africa, which will see a major increase in both city size and urban populations in the future.
No 5 The Antlion
The antlion is known almost entirely in popular culture by its ferocious larval form. Antlion larvae are best known for their habit of building traps, especially in sand dune and scrub habitats. The larvae create a pit through a spiral movement, ploughing material away from the central opening with their abdomen. This not only reduces the time the larvae are exposed to predators while building the trap, but also results in lots of slippery sand grains accumulating on the surface. The antlion larvae then seize and kills any small insect or spider that stumble into the pit. There are around 2000 species of antlion worldwide and over 200 in southern Africa alone. Identification is made easy by the habit of adults being attracted to artificial light at night.