The Reptiles and Frogs of Madagascar

Wildlife photographer Marius Burger writes about the fascinating frog and reptile fauna of Madagascar

South African wildlife photographer / herpetologist/ tour leader Marius Burger, whose marvellous photography and field notes appears in books like FIELD GUIDE TO THE AMPHIBIANS & REPTILES OF MADAGASCAR (Glaw & Vences) and MADAGASCAR WILDLIFE: A VISITORS GUIDE (Bradt, Schuurman & Garbutt), gives us an overview of Madagascar's diverse reptile and frog fauna. Marius also took the pictures.

An extended version of this feature appeared in the marvellous glossy wildlife and travel magazine Africa: Environment & Wildlife,November/ December 1996 issue.

Madagascar is a herpetological treasure trove. A plump blood-red tomato frog, a turquoise chameleon the size of a small cat, a jewel-eyed gecko edged with frills, and other bizarre creatures like golden frogs and flat-tailed tortoises, are just a few of the delights awaiting the avid wildlife enthusiast.

Madagascar is unique - an island continent whose plants and animals have evolved in isolation for more than 150 million years. Due to its proximity with Africa, the flora and fauna have an obvious kinship with the continent. However some Malagasy reptiles have their closest relatives not in Africa, but in distant South America. There are also curious gaps and exciting excesses that make the island's faunal assemblage special. Adders and cobras for example, are conspicuously absent. Also missing are ungulates, wild cats and canids (dogs). But in glorious profusion, are orchids (there are more species in Madagascar than in Africa); half of all chameleons, and the richest primate fauna in the world (albeit restricted to lemurs).

Humans arrived late, only some 1500 years ago, sailing across the Indian Ocean from the East Indies. In a short time they had hunted to extinction all the terrestrial megafauna. Most of the original habitats have been extensively altered, a process which continues largely unabated.

While such habitat changes might benefit certain animals, the majority are usually less tolerant, or entirely incapable of adjusting to a modified environment. Specialist species with very particular habitat requirements often demand near pristine conditions to ensure their survival. In response to this environmental crisis, scientists are actively searching the remaining forest fragments for the survivors of this unique radiation.

Amphibians and reptiles tend to proliferate in tropical areas. Madagascar is no exception. The island's diverse climatic, geological and botanical elements ultimately contribute to its faunal richness and diversity. More than 300 reptile species and 170+ frog species have been identified. In spite of these already impressive figures, new species are being discovered and described at a higher rate than ever. Within the last decade, 49 new reptile species and amphibians have been described while many others await formal description.
One would expect the fauna of at least the nature reserves to be well documented, but this is not the case. For instance, much of the Montagne d'Ambre mountain range in northern Madagascar, currently receives protection by means of a special reserve and a national park which were created in 1958. Despite a history of collecting in the area that dates back over a century, a 2-month reptile and frog survey in 1991-2 more than doubled the checklist. Out of a total of 70 species found for that survey, 37 were new records to the area.

Incredibly, 7 of these proved to be species new to science. Some of the newly discovered reptiles are so restricted that they are obvious conservation concerns. In fact, one new leaf-tailed gecko, Uroplatus malama, is known from only a single specimen from a remnant of low montane rainforest in south-eastern Madagascar. A similar species, U. malahelo, is known from only 2 specimens, collected in 1992, from a minute patch (1500 x 800 metres) of rainforest in south-eastern Madagascar. It is aptly named, 'malahelo' being Malagasy for sorrow. When the specimens were collected, their habitat was already being selectively logged and that forest was not expected to last more than 4 years. It may now be extinct.

The large, attractive new species Paroedura masobe is considered by many to be the most beautiful gecko on the island. It is known from a single site, fortunately within the boundaries of the Zahamena National Park. But its size and appearance guarantee its entrance into the insatiable international pet trade.

Of the approx 170 frog species, a staggering 99% are endemic. In the eastern Malagasy rainforests in particular, frogs are abundant. More than 90 species are known to occur in the 810 ha Perinet Analamazaotra rainforest reserve, making it one of the highest frog species-counts internationally among similarly sized forests. But few families represented, with some being notably absent. These include the almost cosmopolitan Bufonidae (toads) and the limbless amphibians (caecilians), present in much of Africa and the Seychelles.

Photographers would be hard pushed to find more photogenic frogs than the Boophis genus. But good photos do not come easily: to photograph these creatures, one must often spend hours at night in rainforests, trying to home in on their calls. Rainy nights are the most productive: then, frogs engage in a frenzy of calling and spawning. 36 species are currently known in this genus, but this is far from the sum total: since 1990, 13 new species were described with many others awaiting scientific names.

Some of the most popular frogs in captivity are of the genus Mantella. These small diurnal frogs are striking, displaying a variety of vivid patterns. Their brilliant colours may serve to warn predators of toxic elements present in their skin, (aposomatic coloration) a feature that they share with South American arrow-poison frogs. This is an extraordinary case of convergence (parallel evolution). Especially prized is the Golden mantella Mantella aurantiacea, of which thousands of specimens are exported annually to America and Europe for the pet trade.

Malagasy microhylids include a multitude of shapes, colors and sizes, and are represented by 10 genera. It is in this family that most new species still have to be described. The best known species is the tomato frog Dyscophus antongili, an obese red species that secretes a toxic substance from its skin to deter predators.

Most Malagasy frogs do not follow the typical amphibian life cycle in which eggs laid in water, hatch into tadpoles that metamorphose into small frogs. The many Mantidactylus frogs lay eggs on the forest floor near water, or on vegetation overhanging streams. The tadpoles emerge and wiggle their way towards water, to complete their life cycles in the usual way. But some frogs have skipped the free-swimming tadpole stage completely and are terrestrial breeders. One such genus is Stumpffia: these minute frogs lay eggs in foam nests hidden among leaves on the forest floor. The non-feeding tadpoles develop directly into tiny froglets. Those of S.pygmaea measure less than 3mm in body length, making them the smallest frog - if not the smallest of all vertebrates - in the world.

The most striking feature of the more than 80 species of Malagasy snakes, is the absence of deadly venomous varieties. All are clinically harmless. Larger non-venomous species may inflict a painful bite, but the back-fanged species possess venoms that are either too weak or produced in too low quantities to be of any danger to humans. With such an absence of dangerous snakes one would expect the Malagasy to have no fear of snakes. But this isn't the case. For one, the harmless "fandrefiala" Ithcyphus miniatus, is feared around much of the country. Local people believe it drops tail-first from trees, stiff as an arrow, to stab any passing cattle or humans.

The largest snakes include 3 boas, whose closest relatives live in the Amazon basin. (Pythons, which abound in Africa and Asia, are absent from Madagascar). All 3 boas are protected from the international trade, but their flesh and skins are increasingly exploited; belts and other articles are often found for sale in markets.
New snakes are being discovered on a fairly regular basis. One of the island's most unusual serpents is the twig mimicking spear-nosed snake, Langaha madagascariensis. This species exhibits sexual dimorphism, the sexes being different in coloration and in shape of their nasal appendages.

Lizards are abundant on Madagascar, with more than 210 species in 5 families, 4 of which are common in Africa. Absent however, are common African and Asian lizards like lacertids, agamas and monitors. Repeating the theme found in snakes, the island is home to a few iguanid lizards, a group otherwise restricted to the Americas and a few Pacific islands.

Madagascar is justifiably famous for its chameleons - it contains around half the world's species. Among these are the world's largest and smallest chameleons. Most peculiar are the small, stump-tailed Brookesia species. They clamber about on leaf litter on the forest floor where their drab colours and twig-like body shapes make them close to invisible to casual observers. Of the more typical chameleons, Oustalet's chameleon Furcifer oustaleti and Parson's chameleon Calumma parsoni are immense, both exceeding 60 centimetres in length.

The appearance of many chameleons differs so markedly between the sexes that to the uninformed, they may seem to be of different species. This radical sexual dimorphism is best illustrated by F. minor and F. labordi, in which only males possess extravagant nasal appendages or 'horns'. Females are more brightly coloured, however. While tourists tend to be fascinated by chameleons, local people might find them repulsive. Consequently, they are subjects of various Malagasy proverbs and taboos.

Day geckos (Phelsuma) and leaf-tailed geckos (Uroplatus) also elicit great excitement among visitors. Day geckos' brilliant neon coloration, abundance and approachability make them perfect subjects for photographers. In contrast, the leaf-tailed geckos are masters of camouflage: not only are they cryptically coloured, but some have ragged fringes along the throat, body and limbs - particularly U. fimbriatus and U. henkeli. When pressed against a tree, these fringes break the outline of the body and prevent a telltale shadow. With more than 300 teeth, the fringed gecko U. fimbriatus, has more teeth than any other reptile or mammal on earth.

Iguanids and gerrhosaurids are conspicuous medium to large diurnal lizards. They inhabit forests, deserts and rocky outcrops. The gerrhosaurid Zonosaurus maximus, is the largest Malagasy lizard, and locally is known as 'petite caiman', due to its size and aquatic habits.

4 of the island's 5 terrestrial tortoises are endemic. The plowshare tortoise Geochelone yniphora is probably the world's rarest tortoise, and is confined to a small area around Baly Bay in northwest Madagascar. To insure its survival, the Jersey Wildlife Preservation Trust established a captive breeding project at Ampijoroa Forest Station, but this very successful project suffered a severe setback in mid 1996, when 2 adults and 73 juveniles were stolen from the centre and smuggled to Europe for the international pet trade.

Another rare species is the flat-tailed tortoise, or "kapidolo" Pyxis planicauda, which means 'tomb tortoise' in Malagasy, so named because many are found in the tiny patches of woodland left protected to conceal Sakalava burial tombs.This small species aestivates most of the year while it is dry, only emerging in response to the rains in January to April. The island's smallest chelonian is the spider tortoise, P. arachnoides or 'kapika'. It inhabits the spiny desert in the semi arid south, along with the large, common Madagascar radiated tortoise Geochelone radiata. The latter is heavily collected for the pot and for the pet trade.

Of 4 resident freshwater terrapins, only the Madagascar big-headed turtle Erymnochelys madagascariensis, is endemic. Its also the only Old world representative of a family otherwise local to South America. The species is protected by law, reinforcement of which is virtually impossible however. And, many are caught accidentally in seine fishing nets, and eaten. It is also very sensitive to exploitation of its habitat, the western Malagasy wetlands. One factor contributing to its decline, is a long juvenile stage and large adult size. It becomes large enough to eat long before sexual maturity. (Marine turtles too, are heavily exploited in Madagascar; a 1971 survey revealed that annually, some 13 000 are killed along the Malagasy coast).

From the above synopsis, its painfully clear that Madagascar's herpetofauna is in huge demand for the international pet trade. Until the mid-1980's, Malagasy herps were poorly represented in the exotic pet market. But this is not the case today. Between 1986 - 1991, some 145 000 specimens of 17 day gecko species, were exported from the island. CITES figures for chameleon exports from 1986 - 1991, indicate 38 325 specimens from 21 species!
But the most apparent trade book of Malagasy herps is among frogs: for instance, legally exported mantellas skyrocketed from 230 specimens in 1980, to 11 058 in 1989.
BIODEV, a Malagasy task group working in conjunction with the IUCN, has investigated the economic potential of frog and reptile exports from Madagascar.

They calculate an economic potential of US$ 1 million (including $ 150 000 for chameleons and $ 240 000 for day geckos) per annum. This takes into account that most of the economic benefit from this animal trade will still accrue to the importing countries, where sales of Malagasy chameleons alone will probably top $ 1 million. In terms of foreign revenue to the Malagasy people, this trade will be equivalent to clearing some 16 000 hectares of Malagasy forest every year.
Such a reversal in conservation priorities from protection to utilisation can only work if profits from sustainable harvesting are equitably distributed to the people whose survival currently depends on cutting and burning their forests. In reality however, this is not the case.

Currently, the huge profit margins obtained exploiting Malagasy reptiles and frogs benefit just a few individual importers and exporters. A Malagasy villager collecting a day gecko, will earn a measly Fmg (Malagasy Franc) 50 (about US$ 0. 03), whereas the local exporter sells the animal for US$ 9 - 13. By the time it sells in the USA, it will fetch US$ 75. In other words, there's a 2500- fold price increase. The big question then, is: can Malagasy villagers be expected to protect forests and value sustainable harvesting when they make only US$ 3 for every 100 lizards they catch?

A possible solution could be for Malagasy authorities to place greater emphasis on nature tourism, to encourage more people to visit the island and to place greater value on protecting their wildlife. There's no doubt that Madagascar can be a prime tourism hotspot, what with its amazingly diverse wildlife, which impresses any naturalist. But can frogs and reptiles really serve as a draw-card, when most people view them with abhorrence? Here, we need to cite examples where certain reptiles are big tourist attractions: the Komodo Dragons of Indonesia, and the giant tortoises of the Galapagos, illustrate this perfectly. Annually, they attract thousands of tourists to their home territories, as remote as these may be. Nesting turtles elsewhere in the world, do the same. If this is the case, then Madagascar's exceptionally diverse reptile and frog fauna too, is sure to draw the crowds.

Marius Burger will be escorting two Madagascar Wildlife Discovery tours for Rainbow Tours in 2001. The tours cover not only top hotspots for Malagasy reptiles and frogs, but also for other fauna such as mammals, birds and invertebrates. See the relevant itineraries on our site, or mail us for further information.