Treasure hunt into the Sperrgebiet

Not only is the desert alive, but sometimes it is virtually teeming with small creatures. This is the conclusion drawn by 17 learners from Windhoek and Karasburg who participated in an excursion of EduVentures into the Sperrgebiet in August. They collected 4,365 samples of insects, spiders and reptiles for the scientific collection of the National Museum. “We never collected as much material as this on any of the previous eight expeditions”, says EduVentures’ Tharina Bird. “And it is highly likely that we have discovered totally unknown species.”

Members of the EduVentures expedition into the Sperrgebiet. (Photograph by EduVentures)

The learners presented the results of their excursion in the National Museum on Friday. Guests were given an impression of the scenery, the plants and animals during a slide show. The Sperrgebiet may only be entered with a special permit issued by diamond company Namdeb. The excursion explored two mountain ranges, the Kowis and Tsaukaib Mountains, about 30 and 60 km east of Lüderitz respectively. The mountains form part of the northern fringe of the Succulent Karoo, the most bio diverse desert on earth. This is also one of the reasons why so many small animals were found there. “The timing of our expedition was just right”, added Bird. “After the exceptional rainfall this year there were plenty of plants, insects and spiders.” With a total of 2,985 samples, insects made up the largest part of the collected material. Of particular interest were bagworms - moth larvae which camouflage their cocoon with pebbles or, depending on the species, with small sticks or the fluffy seed coverings of the wild rosemary bush; or the grasshoppers which look like rock and can fold back their tentacles into grooves on their head; or the monkey beetles with the peculiar eye markings many have on the abdomen which make them look like a little monkey when they move their hind legs up and down while drinking nectar from a flower.

As arachnologist (spider expert) of the National Museum Tharina Bird is particularly pleased about the 801 spiders and 547 arachnids (scorpions etc) which were collected. “Approximately one third of the spiders are adults and half of those are males”, she says. “Usually the share of adults is around ten percent of which a quarter are males. The reason is that spiders, very generally speaking, become sexually mature after nine months; females then live for another three months, while males stop eating and usually die within one month.” There should also be several new species among the insects and spiders. Scientists believe that worldwide only about half of these groups of animals have so far been found and described. When the collected material has been looked through and identified as far as possible, ‘unknown’ samples have to be sent to experts. Confirmation that it is indeed a new species can only be expected several months later. Last year EduVentures discovered a new spider species in the Fish River Canyon area as well as several samples of the gladiator insect, belonging to the new order Mantophasmatodea, which was first discovered on Brandberg Mountain in 2002 and which caused a worldwide stir.

EduVentures expeditions always head for remote areas from which not much biological material is available yet. Through each of the EduVentures excursions the collection of the National Museum thus receives valuable material – veritable treasures of science. At the same time the expedition leaders introduce talented and motivated learners to the basics of scientific work and get them enthusiastic about nature’s wonders. The existing variety of schools allows for interaction between different population groups – like in this case A. Shipena Secondary School (Katutura), Deutsche Höhere Privatschule (DHPS, Windhoek), and Namibian Institute for Special Education (NISE, Windhoek) and Karasburg High School.