Another perfect day for searching and collecting those evasive specimens still not found, and the 6 Toyota Hilux and Fortuners vehicles with all members of the different scientific teams and members of the media set off for Bainskloof, about 50km west of Worcester.
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| Bains Kloof Bridge |
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| Group Pic |
After completing the Michell’s Pass in 1840, Andrew Geddes Bain decided to build a pass through the Wellington Mountains. He was one of the famous Bain construction engineers who built many passes in South Africa.
Bain described the landscape as “repulsive and savagely grand” and “for the first three miles we had nothing but crossing and recrossing the river and climbing up the mural banks at the risks of our necks, so gloomy was this place, there is a perfect absence of animal life.”
Work started in February 1849 on the easier western approach. This section required little blasting, and two timber bridges and four stone culverts. He also had 300 oaks planted for shade.
He also tried to shorten this part of the route by building a 122m tunnel, but the rock face soon proved too unstable and dangerous. In 1851 he moved his camp to Tweede Tol to start work on the remaining, more difficult part of the pass. Ten kilometers of road had to be blasted through solid rock, and in places 20m high retaining walls had to be built.The workers used little more than hand drills, sledge hammers, steel bars, picks and shovels.
Most of the work was done by convict labour - between 300 and 350 people at a time. Sometimes the figure went up to 450. About 1,000 convicts could claim that they were involved in building the 30 km pass.
The pass was opened in September 1853 and is still in use today - with a few minor improvements like getting a tarred surface in 1934.
It became a national monument in 1980.
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| Dr. Dai Herbert |
The scientists who are looking for mollusks or snails had a very successful day and found a very rare and poorly known species. There are very few records for this particular snail and it seems to be confined to the mountains in the region between Wellington, Ceres and the Grootwinterhoek area. It belongs to a family of snails, the Dorcasiidae, that is endemic to south western Africa. Most of the species live near the coast and some are capable of living in near desert environments, but this one is unusual in that it occurs in montane fynbos. Our snail folk were also pleased to find some living examples of a small pinwheel snail, which again seems to be a species restricted to montane fynbos. In these habitats snails are very few and far between, but the few that do occur there are particularly interesting and their conservation is a matter of concern because of their limited distribution.
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| Find of the day -Tulbaghinia Isomeriodes |
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| Mary Cole |
A few comments from the Mollusk Expert Group
According to Dai Herbert (Kwazulu‐Natal Museum), with its emphasis on the barcoding of alien and invasive species, Toyota Enviro Outreach 2012 will make an important contribution to our knowledge of introduced snails and slugs in South Africa. Many of the most adept hitchhiking snails belong to families where the differences between species are small and they are therefore difficult to identify – even for specialists in their native range. This problem is even greater in countries to which the animals are introduced, because the necessary taxonomic expertise is often lacking. As a result some introduced species have in the past been mistakenly redescribed as newly discovered native species. Currently we know of 34 snail and slug species, which have been introduced to South Africa, but there are a number of others around which raise questions – both regarding their identity and whether or not they represent introductions. DNA barcode data promise to provide valuable insights relating to these questions, helping us to obtain a more accurate picture of the alien terrestrial mollusc fauna of South Africa. A number of species have invaded natural habitats and some are amongst our worst agricultural pests. In this regard the Western Cape is the most adversely effected region with over 30 introduced snail and slug species. Mary Cole (East London Museum) – One difference between indigenous forests in the Western Cape and forests in other provinces where I have collected (i.e. Eastern Cape and Kwazulu‐Natal) is that there are many alien snails in the Western Cape indigenous forests, both in terms of numbers of different species of invasives, and they can be abundant. Forests where I have observed this include: indigenous forests above Kirstenbosch,
Grootvadersbosch and Platbos near Gansbaai. In other respects the forests appear pristine until one scratch in the leaf litter. In the Eastern Cape, and elsewhere, invasive snails are confined mainly to gardens, and while one may come across the occasional slug in indigenous forests, one seldom encounters alien snails. Alien snails and slugs have been in the Western Cape a lot longer than in other provinces, but it is more likely that the climate or other abiotic and/or biotic environmental factors favours them more there than in other provinces, and hence they have been able to establish themselves with greater success. This project will strive to increase our knowledge regarding global biodiversity.
Cornus apserum (formally Helix aspera) introduced European garden snail, was observed
Reflections of the day:
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