BRIEF NOTES ON 
Mantella cowani (Boulenger, 1882)

Marc Staniszewski
Photograph of M. cowani by the author

Care and Maintenance
Cowan's Mantella or Cowan's golden frog (Mantella cowani) is a rare, possibly endangered, species endemic to Ambositra in East Betsileo eastern Madagascar to Fianarantsoa (Vences et al 1994) at the southern edge of the massif region. It is the most altitude-adapted species occurring at elevations of 1500 2000m (perhaps even greater) and this is an essential consideration for successful care and propagation in captivity. It is restricted to fragmented areas of intact primary or ancient secondary forest where there is good undergrowth and an extensive layer of humid leafy material. It is not always found in the vicinity of water and some populations occur in virtually inaccessible cliff` faces where there is a good growth of native mosses and dense rock-clinging vegetation (personal observation, Madagascar 1994). The vivarium set up and climate control must reflect this species natural preferences otherwise it will not breed. With this in mind I was able to breed from a colony of adults that I acquired at a reptile show in the UK. The adults were maintained in a large (36" x 24" x 24") vivarium landscaped with granite rock pieces and densely planted with Scindapsus, Diffenbachia, 'pothos' and Fittonia as well as a live culture of Java moss on top of a sphagnum moss peat and sand substrate. Only a small, shallow water dish was provided but the ambient humidity was controlled using a Pifco Humidifier (purchased from Index.) Low temperatures, in the range of 16 – 20°C. were provided during daytime. At night I had recorded low temperatures of just 7.8°C in 1670m altitude cliffs 4km north of Ambositra.

The animals were given a period of dormancy from December to April when they were kept cool (around 15°C +/- 2°C) and: dry (ambient 60 - 74% humidity). Gradually increasing the humidity through misting or with the ultrasonic humidifier until the ambient humidity was around 95% in May and June, while only raising daytime temps by 2 or 3°C, invoked advertisement calls in males. Though M. cowani is an incredibly secretive creature, occasional territorial bouts between males were witnessed in the open. I rarely observed the females especially around the time of egg deposition so I assume that this was at night.

The first clutch was deposited in a cavity beneath a large piece of granite rock on June 1^st 1999 and numbered 26 eggs. Using a ZooMed micropump I ensured slightly acidic (pH6.5) water dripped down this rock and soaked the substrate around the eggs but unfortunately this clutch proved to be infertile. The same female deposited a second clutch in the same place on June 24^th 1999, which numbered 33 large whitish eggs with a nucleus diameter of around 1.8mm (using a 20x Student microscope). Again the dripping method was used. 15 of the eggs developed and were removed to a rearing container by scooping the clutch with around an inch of the substrate and placing it on a mat of Java moss that was half-submerged in shallow water. The spoiled eggs were removed using a scalpel and forceps. During the final stages of nuclear embryonic development the water level was raised to submerge the eggs completely. So far 12 tadpoles are developing, being reared in separate containers (plastic beakers with 2 inches of pre boiled rainwater changed daily) and a clump of Java moss. They are fed Aquarian flake, Sera Micron and crushed gnat larvae. Although development is slow compared to say Mantella aurantiaca, they are just starting to show the limb buds and hopefully I will be able to publish a photographic montage of the egg -tadpole - froglet development soon.

If you remember the rule of KEEPING THEM COOL, you should have no problems keeping these wonderful but secretive Mantellas and perhaps breeding success too.