Street vendors, Arum lilies and Arum lily frogs
Last week Denise and I found a delightful little Arum lily frog in my front garden sheltering in the rain gauge. How the little frog got into the cup, goodness alone knows. Perhaps I should mention that there are numerous arums in the vicinity and it is a known fact that these little creatures use the flowers as shelter. What prompted me to write this article is the concern expressed about the future existence of the little frog and its presumed dependence on the Arum lily.
A campaign was recently launched in Cape Town urging residents to refrain from buying arum lilies from street vendors and to report vendors who, by selling the flowers, are inadvertently endangering the lives of the ‘arum lily micro frog’ which is said to breed inside the water and dew held in the cup of the lilies.
In response the City of Cape Town issued a statement as follows: “According to CapeNature, the City’s Environmental Resource Department and the South African National Bioversity Insititude, this frog does not exist. There are however, two different species of frog, namely the micro frog (Microbatrachella capensis) and the arum lily frog (Hyperolius horstockii). The micro frog is smaller than a fingernail, while the arum lily frog is somewhat larger, growing to about 40mm in length. Furthermore, no frog species breeds in the flowers of arum lilies. While the arum lily frog occasionally uses the flowers for shelter, it is not dependant on them. The little frogs breed in wetlands and not in the flowers of arums. The micro frog is ground-dwelling, breeding in temporary pools, and does not climb into any flowers.
Arum lily frogs are very pale and hide their bright orange feet and legs under their bodies during the day. In this way, the frog is able to use a white background as camouflage against predators. They do not use the pollen of the flowers to camouflage themselves, as has been suggested.
Arum lily frogs are only found in the Western Cape and they are not classified in the 2004 Red Data book as threatened. However, it is true that the species is becoming increasingly rare as their habitat is lost to urban development.”
Despite assurances from the authorities that the little frogs’ dependence is purely based on taking shelter from predators, it must be noted that the faintly scented Arum lily (Zantedeschia aethiopica) attracts various crawling insects and bees which are responsible for pollinating the flowers. The tiny flowers occur on the yellow ‘rod’ which is surrounded by the spathe. The spathe is typically white with a faintly yellow tinge. Flowering season is throughout the year but mainly spring and early summer. A white crab spider of the family Thomisidae visits the flower to eat the insects. This spider does not spin webs and uses its whiteness as camouflage against the spathe. The tiny Arum lily frog, Hyperolius hopstocki also uses its whiteness as a camouflage, and is also attracted to the arum lily flowers. Why? For one simple reason – the availability of food. The spathe turns green after flowering and covers the ripening berries. It rots away when these are ripe and the succulent yellow berries attract birds, which are responsible for seed dispersal. To put the above in perspective: the Arum does not only feed the little frogs, but a number of other creatures also depend on the existence of this lovely, graceful plant.
The sale of ANY illegally harvested flora is a cause for concern: indigenous flora plays a vital role in the eco systems of our region and is increasingly under threat. I suggest we get in touch with the Municipality and SANPARKS to voice our concerns. It is disturbing to see so many vendors walking the streets with arms full of wild flowers, let alone the vendors along the N2 toward Plettenberg Bay – they increase in numbers every week.