Since my early childhood, I have found frogs fascinating. This fascination with frogs has only increased in life the more I found out about them and studied/worked with them. Growing up in Ireland with a passion for reptiles and amphibians can be difficult at times. Our diversity is rather low to say the least; we’ve one species of frog, toad and lizard (including the slow worm brings it to 2 on the lizard front but due to its tiny distribution and its unnatural introduction I tend to discount it) and no snakes. Even still, it was and still is a joy to work with what we have! Some of my earliest memories are of me stalking my garden pond with net and jam jar for frogs, frogspawn, and tadpoles. Later I even purposefully extended the size of my garden pond (plus adding 2 more), removed all the fish, and introduced native plants all in the name of frogs. When I first discovered smooth newts arriving was an extraordinary moment! My amphibian diversity had risen to two! Later in life I have had the opportunity to photograph and study frogs in Indonesia and Nepal, even doing my MSc thesis on our native Irish frog (Rana temporaria). Globally there is about 4,800 species of frog and still counting! In Southern Africa (including South Africa, Mozambique, Zambia, Zimbabwe, Botswana, Swaziland, Lesotho and Namibia) there is about 160 species and again still counting, with South Africa (where I’m currently based) having a very high rate of endemism. Since arriving in South Africa I have been keen to get involved in any field herpetology work as well as my own specific terrapin research (for further info please read Immersed in the world of the crocodile, It pays to have a hard shell up here! and A nocturnal hunt for the “lions of the ground”). On saying that, I felt I have let frogs unfairly slide down my priority list. So, when I found out that Nick Evans was organising an evening frogging less than an hour’s drive from me in a small protected area on the outskirts of Durban, I couldn’t think of a better opportunity to learn more about South African frogs and return to some childhood fun.
Throughout KwaZulu-Natal and South Africa, Nick is renowned as an excellent field herpetologist, so I was really looking forward to the evening and learning as much as I could (for pieces by Nick on BioWeb.ie please see here ). On arriving at the site, it was a mild evening by KwaZulu-Natal standards, with a heavy mist in the air, but thankfully no serious rain. The site was small and surrounded on three sides by industrial property. Within the site though was high meadow grass habitat, forested habitat and many small ponds and pans. Seeing the site, I had memories of surveying the golf courses for frogs back home for the thesis, it seemed so familiar to home, not the huge wild expansive Africa the BBC or NatGeo tends to show. Although the site seemed just like a small wetland or park back home, one thing immediately stood out, the sounds. Just standing by the car putting on my wellies Nick could identify at least 4 species by their calls: painted reed frog, natal tree frog, red toad, and bush squeaker (fantastic name I know!). Things seemed a little slow to begin with, until we made it to the second small pond system with a wooded area on one bank, again the different types and number of calls was overwhelming. The first frog we came across was a Natal tree frog (Leptopelis natalensis). To a frog enthusiast this animal was stunning, with its bright red eyes, pale greenish skin with splashes of bright green, and his obvious round pads at the ends of the digits making it a fantastic climber. Our second find of the evening, was the Natal leaf-folding frog (Afrixalus spinifrons). Based on current data this species is listed as threatened by the IUCN. As the name suggests this species will fold leaves together to avoid detection by predators and to lay its eggs in. Up next was the bubbling kassina (Kassina senegalensis), another fantastic name! This animal had bulging distinctive eyes with different shades of brown being the most predominant colours. What was so interesting about this frog was his mode of locomotion Unlike normal frogs hopping, it had a distinctive fast little jog/dash, which was very amusing to watch.
Leaving the second pond, we began walking up hill towards the next, to our left an open high grass area and to our right a wooded forest area. During the walk, we could hear red toad (Schismaderma carens), clicking stream frogs (Stronglopus grayii) and plaintive rain frogs (Breviceps verrucosus). Unfortunately, these frogs were not visually encountered but hearing them, knowing they were present was a great feeling, especially considering the size and location of this small wetland habitat. On the way to the third pond we were also very lucky to spot a flap necked chameleon, Chamaeleo dilepis. Although not a frog or even an amphibian, I think this species is worth a mention as they are such a beautiful lizard, and herpetology is the umbrella of reptiles and amphibians. The flap necked chameleon is South Africa’s only normal sized species of chameleon, for want of a better term, the other species being dwarfs. Nick estimated the one we encountered at only being 1-2 years old so still quite small anyway.
On arrival at the third pond, we came across quite a few stunning painted reed frogs (Hyperolius marmoratus). This species is common and widespread; even so I think they were my second favourite frog during the survey purely because of how photogenic they are. They truly are a pretty frog! There are three subspecies of painted reed frog; the subspecies we encountered is endemic to coastal forests in and around Durban and nowhere else.
Other species encountered at the 3rd pond that I was either to slow to photograph or because my flash was letting me down that night included common river frog (Amietia quecktti), bronze cacos (Cacosternum nanum), African clawed frog (Xenopus laevis) and possibly my favourite name of the species spotted, the snoring puddle frog (Phrynobatrachus natelnsis). I strongly suggest anyone who is interested to do a quick internet search of these species for photos and a bit on their natural history. Some frog enthusiasts may recognise the African clawed frog by its scientific name Xenopus laevis, as the most likely culprit for spreading the deadly chythrid fungus. This species is unaffected by the disease, making it a suitable vector. The first well-documented method of human pregnancy testing involved this species, and as a result, large-scale international trade in living African clawed frogs began more than 60 years ago. If chythrid fungus originated in Africa, the African clawed frog seems a likely vector of the initial spread throughout the world.
For our final site of the evening, it seemed Nick was saving the best until last. He told us on our way that this is one of the very few places in and around the Durban area that he has encountered the Kloof frog (Natalobatrachus bonebergi). This species is classified as endangered by the IUCN and is only found in coastal and dense canopy forest in northern Eastern Cape and eastern KwaZulu-Natal. Urban development and sugar cane plantations are the greatest threat to this species’ survival, and the local endangered species trust is working hard to monitor it. As we approached the site, I did sense it was slightly different in habitat to the other ponds we had visited. It was smaller and in certain spots, there was flowing water running through, but the main difference was it was more densely vegetated, with many branches overhanging the water-bodies. Nick explained this was the very specific habitat the Kloof frog relies on for a number of reasons, one of which is it prefers to lay its spawn clump high above water away from predators on a thin overhanging branch, so when the eggs hatch tadpoles can drop directly into the water below. In the end, we saw three adult specimens and a spawn clump! It was rewarding to see that this small patch of habitat still had Kloof frog present, especially in such a built up urban area. The discovery of the spawn clump was also a great bonus to the short term future of the species here.
The evening unfortunately then came to a close, but in just two and a half hours we’d seen 10 species of frog including near threatened and endangered species, plus heard an additional 3 species calling, and a flap neck chameleon. This diversity was contained within a small locally protected wetland surrounded by a concrete jungle! As I mentioned before when people think Africa they think huge expansive nature and the big five. That is fine, but the wider more detailed picture I find is even more incredible. When you look at the sheer diversity of species, for me in particular, reptiles and amphibians it is so rewarding. Unfortunately though, a lot of these smaller species rely on such small home ranges and distributions and such specific habitat that their protection is becoming increasingly difficult. People like Nick and others who attended the survey are exactly what these species rely on: local people interested and passionate about their wildlife. They teach and share with others what is here, how unique it is, and how valuable these species are to the overall ecosystem.