Zandvlei Trust

Spring Festival  – Wednesday 21 September

About 35 members and friends came to the presentations by Prof Timm Hoffman (Leslie Hill Institute of Botany at the University of Cape Town) and Nathan Meyers (Consultant Entomologist and IT specialist).

Timm setting up the equipment with some help from Erika Foot and Michael Hoarau.

Timm re – introduced us to the ZIMP (Zandvlei Inventory and Monitoring Programme) with 5 years worth of information to give some ideas of what may or may not be happening at Zandvlei. Rainfall is collected by 7 volunteers around Zandvlei presently. He showed with graphs, how by keeping regular records there is almost a 50% chance of determining the salinity levels by knowing the ingress of fresh water into the system. Salinity is measured with a refractometer in daylight hours. There are a few volunteers taking regular readings at given points in Zandvlei and these data are recorded, together with the Scientific Services dept of the City of Cape Town.
He used his bird data to illustrate the seasonal relationship of mainly water birds and the rainfall and this relationship in different parts of the vlei with different salinity levels over annual cycles. The graphs showed the current years data with an averaged 5years records.

Erika Foot gave a presently inconclusive summary of the frog and Leopard Toad census as she and her helpers are still collecting data. In some areas the Leopard Toads are still calling.

Steve Davis gave a short inspirational slide presentation to encourage new people to join the botany section and their impressive collection and achievement. There is much still to do and they have regular outings, you do not have to be an expert to join in.

Gavin Lawson encouraged all to use our web site for sourcing information about ZIMP and Zandvlei in general. It is planned to have data on the activities and records archived on a server for anyone to access especially for the management, research and study of Zandvlei and its Catchment.

Timm ended off encouraging and challenging all to contribute towards this ambitious project by volunteers, to see what can be achieved in the next 5 years. 

The project needs funding to achieve a level of co–ordination and needs to employ someone to produce data for the various records.

 We need more people to collect data for the following subjects;

salinity,
fish,
rainfall,
animals,
terrestrial plants,
water plants,
insects,
anecdotal stories about people, characters past and present in the area.
historical records..........

There are many more that anyone can be involved in, you do not have to be an expert, you only need to be able to count and record what you observe.

Nathan Meyers discussing some interesting insects.

Nathan took us through 12 of about 30 orders of insects commonly found around Zandvlei. He reminded us that insects have 3 body parts – a head, thorax and abdomen usually used to identify them. They usually have 6 legs. Did you know that flies, bees and ants are of the same order? Did you know that a dragonfly has 4 wings and they move idependently of each other, enabling it to hover and fly off in any direction?

Nathan has collected, identified, labelled and mounted a small section of the insects found at Zandvlei. These are housed in small portable wooden boxes with glass windows..
He initiated a valuable software database for the describing and the indentification of these insects. This database can also be used for the describing of all other plants, birds, fish, reptiles, mammals etc found within the City of Cape Towns Nature Reserves. It could be an invaluable management tool.

 It needs funding to move this valuable resource and data project along.

At the Cape Town Museum entomology reference section, Nathan had to carefully study and consult with the experts to correctly identify and describe all the specimens with the correct labels. This is the scientifically accepted method.

Very little is known and understood how valuable insects are to keeping the Fynbos alive. The Fynbos biome was declared a World Heritage site in 2004. It is the smallest biome, it takes up less than 1% of the earths land surface, yet has about 22 000 different plant species! 
Not enough information is available on this subject.