How many ant species do you know? Chances are that you're familiar with the persistent little black things that creep out of the cracks in the floor in dry times in their hundreds, and maybe the glossy brown semi-translucent 'sugar ants' that scuttle out of the sugar bowl some mornings.
Nature documentary fans may be familiar with the photogenic 'leaf cutter' ants that chop down leaves to feed their fungus factories, but few would guess that the beginnings of an ant diversity study in the Kruger National Park has turned up an astounding 85 species of ants. Hendrik Sithole, manager of the invertebrate research department in Kruger, has been glued to his microscope for some time.
Looking at tiny features such as the number of sections in ant antennae, spines, appendages, the number of hairs on certain body parts, and other minute details, he has found 85 species of ants from 30 different genera. Hendrik has been working together with other overseas researchers on an ant diversity and distribution study since 2003. During the wet season ant pitfall traps are left in grids in the veld, filled with water and an anti-evaporant liquid.
So far 12 sites have been sampled in the park, which has been divided into some 200 sites. The ants are collected from the field after five days, and then textbooks, tweezers and time are used to identify the species, and to count the number of ants from each species. Hendrik presented his findings thus far at the Entomological Society of Southern Africa's 15th congress last month. Interesting findings include three sites that each have 17 different species of ant that were found only at those three sites.
Many ant species seem to be unique to individual sites, with the most abundant species only being found at four sites. Two other species were found at three sites each. Even sites relatively close to each other in the same landscape type were found to have different species dominating in the pitfall traps. The south-west and north-west sampling sites appeared to have more different species overall than sites sampled in the far east of the park.
The ant sampling will continue to monitor this one facet of biodiversity over time, and some things seem certain. The total number of species of ants found will rise well above 85, and Hendrik will continue to be delighted by the glossy creatures in his microscope's field of view. Next time you take a walk in the park, take the time to put your nose close to the ground and see if you can spot some of the more obvious differences in the ants underfoot.
By Melissa Wray
In Kruger National Park