Aquatic environment

Hands-on education a hit in biodiversity hot-spot

Frog Night at Chrissiesmeer provides visitors with the unique opportunity to catch, and identify some of the amphibians in the Lake District. Petro Kotzé Petro

An eco-tourism initiative in Chrissiesmeer, Mpumalanga, for the One particular weekend, at the Chrissiesmeer is teaching young past 13 years. beginning of each December since Located just over 20 km from 1997, is an interesting weekend to be and old to catch on to conservation. Carolina, a stone’s throw from the a frog around Chrissiesmeer. About Article by Petro Kotzé. Swaziland border, the Chrissies- 160 people of all ages head to the meer village itself is but a handful area for Frog Night. Presented by s the sun sets, the choir of streets surrounded by a lively the Matotoland Eco-Tourism Asso- starts a vaguely organised community dependent mainly ciation, the event not only educates array of snores, rings, whis- on farming and forestry. A small guests about the amphibian species Atles and pings. The audience is ready sign at the entrance provides the found in the area, but gives them for the show, donning the necessary first clue to where the town’s pri- a chance to get to know them first headlamps and plastic bags. This is orities lie, as it warns drivers to hand, literally donning sneakers and no ordinary performance, especially slow down…for the frogs. “This is plastic bags to catch them in one of not from the elated crowd. Rather, it probably the only town where you the abundance of local pans. is a somewhat alternative choice of will have rocks thrown at your car However, visitors to Chrissies- entertainment, especially for a week- if you run over a frog,” the barmaid meer who think that frogs are the end in the countryside. Welcome to in the town’s oldest, and only hotel, area’s only claim to fame are dearly Frog Night, an annual highlight in says cheerfully. mistaken.

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More than meets Really an elevated plateau, the the eye MLD is a unique geomorphic entity. In fact, it has been described n general, pans in as a glimpse of one of the most Iare spread in a band across the ancient land surfaces in southern interior. The bulk sits in the drier, Africa and between 10 and 20 mil- western part, around the Northern lion years old. Frogs are not the Cape, Free State and North West only reason why visitors should Province, while a unique cluster in tread carefully, underfoot is possi- the eastern part is centered in bly one of the last remnants of the Mpumalanga around , post-Africa I surface.

“This is probably the only town

where you will have rocks thrown at Kotzé Petro your car if you run over a frog.” in the ‘rejuvenation’ of rivers in the Above: Frogs are interior. As a result, downwards placed in see-through, inflated bags for easy Post Africa I and II refer to peri- and headwards erosion took place, the largest natural body of freshwater identification, such in the country (with a circum­ference ods of uplift and tilting of the sub- removing the veneer of ancient soil as this Rattling Frog of 25 km). Some 270 pans are scat- continent (respectively 20 million and exposing younger erosion sur- (Semnodactylus tered in a 20 km radius around the and 5 million years ago) that resulted faces. Some of the old land surface wealii). village of Chrissiesmeer, and are also less saline than their western counterparts. Here, a number of features are of significance. Even though there are no rivers in the area, it’s sur- rounded by the drainage basin of four river systems; the Vaal River, which eventually turns into the Orange at Douglas and ends in the Atlantic, is one. The Komati, which then flows past Komatipoort to Mozambique, is another, while the Usutu River that ultimately empties into Maputo Bay is the third. The last is the uMpuluzi. The perennial (during normal rainfall seasons) pans of the Mpuma­ langa Lake District (MLD), as the pan field is known, receive water in a number of ways. Rainfall and run-off from surrounding watersheds are two sources. Some water also per- colates into the ground to become groundwater, of which a small amount migrates into the pans. Furthermore the area, spe- cifically the Tevreden Pan Peatland Complex in the northern part of the MLD represents a unique wetland type uncommon in the South African landscape, namely peat- Left: The Rattling lands (also refer to The Water Frog (Semnodactylus

Wheel, July/August 2010). Kotzé Petro wealii).

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significant region, one night in December 2010, a question was posed: “How do you catch a frog?” Snores, rings and whistles

he answer came in a confident Tvoice from among a hoard of excited, young faces: “You throw it with your Croc!” can still be identified at the MLD, Did you know? Luckily for the MLD’s 13 frog where it is slowly being eroded being species, explained the night’s encroached by head-cutting of the speaker, herpetologist Jerry Theron, here are no Rain Frogs in the four rivers mentioned earlier. the answer is much more diplomatic: TMLD. It is speculated that the The origin of the pans is still a You listen to them. Male frogs call predominant soggy (clay) soil is the matter of speculation. A popular to attract their mates. Most females hypothesis was put forward by the reason, as the species prefer sandy have no larynx, with the one excep- late Prof John Wellington. He theo- soil for breeding purposes. During This Common Caco tion in South Africa being the female rised that the pans can be linked to (Cacosternum mating, the male of this species Platanna. Each frog’s call is like a form an eastward flowing drain- boettgeri) was one of fingerprint, and is species-specific; a is glued to the back of the female age network, which once formed a the many caught on the night. deep vibrant snore for the Guttural (with a sticky secretion). The eggs tributary network to the ancestral are laid in burrows, within which the uMpuluzi. When head-cutting by tadpoles develop and emerge from the Vaal River cut into this drainage as fully formed froglets. network, it was deprived of its water and rendered moribund (stagnant) No one is sure what the lifespan as the water was diverted to the Vaal of a frog in the wild is (being under- itself. Westerly winds formed dunes standably hard to track) but Bullfrogs with sand from the river beds, in captivity have lived up to 25 years. which divided the drainage network This hardy amphibian buries itself into a series of isolated segments during times of drought, where it (the pans). Other hypotheses include is able to slow-down its breathing regional warping of the sub- and heartbeat to almost zero. It can continent (the pan belt coincides remain in this state for years at a with a continental-scale drainage time. divide that divides northerly from The female Foam Nest Frog is southerly flowing tributaries) or fertilised by about ten males at even the occurrence of exception- ally dry periods that coincided with her sides, which generate foam by the ice ages in the Northern Hemi- churning the egg jelly with their sphere. The thought is that reduced hind legs. Nests are common in trees vegetation during these times would that overhang pans in the bushveld. have promoted the formation of When the tadpoles hatch, they fall wind-blown sand deposits along the into the water below. courses of the rivers. Around 20 million or so years Petro Kotzé Petro later in this same geologically

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Toad (Bufo gutturalis), a clear ‘quoip’ for the Bubbling Kassina (Kassina senegalensis) and a piercing ‘pip’, sometimes in short bursts, for the Striped Stream Frog (Strongylopsus fasciatus). Incredibly, what would sound like a confusing choir of clicks, pips, snores, rings and whistles to the untrained human ear, is a clear signal for female frogs that indicate potential mating sites. The amphi­ bian ear is exceptional, particularly since the female can only hear the ‘voice’ of her specific species. The sounds, formed by blowing air over the vocal chords into a vocal sac that resonates, differ in frequency, pulse rate and duration, making each quite unique. As for female choice, choir leaders apparently stand a better chance to be selected, while size and age (bigger and older being the preference) are also possible deal-breakers. Calls, however, can also indi- Digging deep to save the MLD cate if a male frog’s territory is encroached upon. “The Painted Reed Frog, for example,” explains he pristine pans of the MLD are under threat MLD declared a Ramsar site, in order to offer the Theron, “has an inter-male spacing Tfrom rampant applications to develop open coal area more protection. The Ramsar Convention, of 50 cm.” If this space is entered, the mines in the area. In fact, says Mpumalanga Lake otherwise known as the Convention on Wetlands mating call changes to a territorial District Protection Group (MLDPG) project-coordi- of International Importance, is an intergovern- call. A River Frog’s usual ‘click-click- nator, Koos , there is literally not one farm in mental treaty that provides the framework for click’ changes to a feisty ‘meow’ and the region between Carolina, the Warburton Road, national action and international cooperation for a somewhat gentlemanly vocal fight and the Lothair/Ermelo Road that has not received the conservation and wise use of wetlands and results. an application for prospecting rights. their resources. During the December Frog Night, The trend, explains Davel, is for any investment Studies have shown that the bulk of the aquatic the talk on the aspects of the breed- or financing company, which has no interest in biodiversity in the area is irreplaceable, while the ing ecology of South African frogs mining, to apply for easily-attainable prospecting water is almost pristine. Geohydrological investiga- was followed by a visit to a nearby rights. Once the potential for coal mining can be tions of fountains on the farm Lusthof have proved pan, just as the sun was setting (most frogs are nocturnal). In summary, proved, the mining right is then re-sold for huge the exceptional quality of water, rated substantially frog hunting is dirty work. More amounts of money to mining companies. cleaner than the South African Class 0 (ideal) specifically, it is wet, muddy and not The MLDPG has been vigorously opposing these drinking water quality. “The water is so clean,” says for the feint hearted or impatient. applications, as opencast coal mining will disrupt Davel, “I can still see birds feast on fresh-water Theoretically, they occur around the the hydrology of the pans and cause irreversible mussels in a vlei nearby my property.” shallow edges of the pan. pollution. The organisation, with the Mpumalanga The fight to save the MLD from development The trick is to listen for the call, Tourism and Parks Agency (MTPA) aims to have the is ongoing. approach the direction slowly

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Sources Petro Kotzé Petro • www.chrissiesmeer.co.za The collected species are • Mining and conservation of the (at which point they will most likely Frog Night, after the prize giving and identified before being stop, having been disturbed), wait, frog count. Mpumalanga Lake District by T released back into the and repeat the exercise. As a rule, Even more encouraging is McCarthy, B Cairncross, J Huiz- pan where they were enga and A Batchelor (published found. captured frogs are kept in clear, the increasing amount of people on www.chrissiesmeer.co.za) inflated, plastic bags for easy iden- interested in attending the festivi- • The Tevredenpan Peatland tification. On the night, eager faces ties – this year, they had to show Complex of the Mpumalanga (of both the young and the young at many away. “Frogging” (as it is also Lake District by P Grundling, heart) then discussed size, call, skin referred to) is by no means a com- A Linström, R Grobler and J texture and so forth for purposes of mon choice for a weekend activity Engelbrecht (published on www. identification. “Kids rarely get the but, by the looks of it, Chrissies- chrissiesmeer.co.za) chance for an opportunity like this meer and the Frog Night’s encore • Sasol First field guide to frogs of Cape River Frog to learn more about nature,” explains will resound for a long time still to th” Southern Africa by Carruthers V. (Amietia fuscigula). Theron at the end of the “Lucky 13 come. (2001), Struik Publishers. • www.ramsar.org Petro Kotzé Petro

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