08 Sept, 2008

In a Namaqualand flower sits a bagworm, another creature - like the tortoise - that carries its home around.

We returned to the Goegap Nature Reserve, south-east of the town of Springbok in the Northern Cape province of South Africa. Here we searched among the striking rock structures for more of nature's little creatures.

The Namaqualand sandveld comes to life with the coming of the flowers, and the many different insects that pollinate those flowers, and the small animals and reptiles that feed off those various invertebrates.

The succulent plants are coming into their own as the sandveld begins to dry, and protruding through the beds of mauve and purple flowers are large mounds of granite boulders which have been weathered by wind and sun over many millennia. They, too, give shelter to much of this life.

Plodding through the underbrush came an angulate tortoise … obviously on a mission, and the pink colour of his gular shield indicated that the mission might have something to do with a female tortoise.

This single gular shield, which protrudes forward from under the tortoise's head, also confirmed that this was definitely a male.

The gular shield is used as a battering ram in male-to-male contests. Males use this protrusion to overturn and batter an opponent.

This angulate tortoise was very beautiful, with distinct markings on its shell, and this individual seemed to be in about the middle years of its life. They can live for up to about 35 years in favourable conditions.

This species is endemic to southern Africa, and is the sole member of its genus. Although quite a hardy generalist, the angulate tortoise is, like many tortoises, vulnerable to veld fires, and unseasonal wildfires can have a marked influence on population sizes.

The home range of a tortoise like this one would be about 2.5ha (6 acres), and as a generalist feeder it would subsist on grasses, annuals and succulents.

One particularly interesting fact about tortoises is that they are able to drink by sucking water in through their nostrils.

Off he plodded in his shell or his 'travelling house', and as he passed a succulent flower bush with some striking pale yellow flowers in full bloom, I saw in one of these flowers another little creature with which I am fairly familiar … a bagworm.

Now this is one of nature's particularly interesting little configurations. This creature also has its own peculiar little 'traveling house'.

Newly hatched larvae of these species use vegetable debris, thorns or sticks to construct silk-lined portable cases in which they live out their life cycle. The sticks, as in the case of this particular individual, adhere to a substance excreted by the larvae, serving both as a protective case and as a camouflage in the local environment.

Both males and females pupate within this constructed case or 'home', and the female is able to turn around within the case, and to lay eggs before she dies. These eggs then hatch, and the newly hatched larvae or worms then head off and attract or construct their own travelling cases.

– by Paul Myburgh, Earth-Touch crew © Earth-Touch

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