Bees tend to
have a high species diversity in arid areas, particularly those with a mediterranean
climate. South Africa, being a largely arid country, has its fair share of bee
species, but when there are no rains and consequently no flowers, they cannot
be found. As with most insects, solitary bees breed through the summer and
their progeny emerge during the following summer to reproduce. Therefore, productive
bee collecting has much to do with the previous summer’s weather.
During 21
November to 1 December 2016 the bee team began fieldwork. The team consisted of
Elisabeth Khumo Mwase and Connal Eardley, who spent a day collecting at each
site. One day is adequate to sample a square kilometre for bees.
The trip
focussed on the East Karoo BioGaps sites. The area was dry, with some sites
being very dry, except for the Black Hill farm that had received rain.
Surprisingly, bee collecting was not much better on Black Hill than on the
other farms, but the results were different because we collected many more small
carpenter bees than elsewhere. With one or two exceptions, bee collecting was
average. A few sites were very dry and bee collecting was poor.
The second
BioGaps bee trip took place in the Central Karoo during 30 January to 4
February 2017. The team consisted of Reinette Swanepoel and Connal Eardley. . Although
flowers were plentiful near Victoria West, bees were scarce in that area. We
had sampled bees there during the previous summer and had found the area very
dry with few flowers; hence the knock-on effect described above. The other
sites, near Beaufort West, Fraserburg and Loxton were devastatingly dry and
bees were non-existent (because we could not find any bees we sampled more than
one site per day). This was disappointing as we now have no bee records from those
areas. It will be interesting to see how long it takes after good rains have
fallen for the bee populations to recover. Let’s hope that the rains come soon
and that long-term sampling can be undertaken.
Near the BioGaps site on Chris Hayward’s farm
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