Ginger Tree Frog

The golden frog is active during the day (3) and lives in groups usually consisting of twice as many males as females (4). It is an insectivorous species, feeding on termites, fruit flies, ants and a huge range of other insects (4). Breeding tends to start after the first heavy rains of the year, and when there is plenty of food. Males attract females with their call (4). The male will then rapidly move himself to the female's back, without embracing her (virtual or cephalic amplexus) (6). The females do not lay their eggs in water, but in damp leaf litter, moss or under bark and rocks next to a water source (4). Each clutch contains 20 - 60 white eggs, each one measuring up to 2 mm in diameter (3); they are fertilised by the male immediately after laying (4). Two weeks later the tadpoles hatch out and they either wriggle into water or are are washed into small pools by heavy rain. It takes around 70 days for the tadpoles to metamorphose into froglets which measure 11 mm in length (3). The typical yellow-red colouration is acquired only after some weeks (6). Sexual maturity is reached 12 to 14 months later, and the average life span is eight years (4).

All mantella frogs are listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), which controls international trade in these species (2). The golden frog is bred in captivity in a number of zoos and other breeding facilities, including the Detroit Zoological Institute's National Amphibian Conservation Centre, which breeds hundreds each year for use in breeding programmes in other institutions (5). The provision of captive-bred individuals to zoos reduces the stress on wild populations caused by collection. Captive breeding programmes may also provide a genetic reservoir of a species to safeguard it should the population undergo a drastic decline or even become extinct; they also provide sources of animals for reintroduction to the wild and allow research to be carried out (5). Although captive breeding is an important facet of any conservation programme, protection of the remaining wild populations and the habitat on which they depend is of great importance (7).

The golden frog is a small poisonous frog which is bright yellow, orange or red with some red colouration on the upper surface of the hind legs (3). It is a member of the Madagascan genus Mantella, the members of which have evolved to be very similar in appearance and behaviour to the very distantly related poison arrow frogs of South America (family Dendrobatidae) (3). In this species, the eyes are typically black, although there may occasionally be golden pigmentation in the upper portion of the iris (3). The legs are short, and the tips of the fingers and toes bear distinct adhesive pads (4). Males are typically smaller than females and have a more angular body shape. The bellies of males are generally lighter in colour than those of females. Two pale-coloured ducts that carry sperm and urine are often visible passing along the belly (4). Males do not call as often as other species of mantella frogs (4); the call is composed of a series of short notes, each of which includes three short clicks (3). The tadpoles of this species do not have external gills, and the eyes are located on the top of the head. Young froglets are olive green in colour with dark marks on the back and the hind limbs feature dark bands (3).

Inhabits Pandanus forests where it is found in sunny areas. They tend to occur amongst vegetation in swampy sites (3).

This frog is endemic to central-eastern Madagascar (6), where it occurs in a highly restricted area at elevations over 900m (3).

Classified as Vulnerable (VU A1cd) by the IUCN Red List 2003 (1) and listed on Appendix II of CITES (3). A revision of IUCN categorisation for the Malagasy amphibians led to inclusion of Mantella aurantiaca in the “critically endangered” category (Global Amphibian Assessment, Madagascar Working Group, unpublished) (6).

This species is very popular in the pet-trade and over-collection of individuals is still carried out at some areas. Although at present there are no signs of reduction of population size due to this take off, it must be carefully monitored in the future to assure the survivorship of the species (6). Furthermore, large-scale deforestation, predation by introduced species, and encroachment by humans are all posing threats to this frog (4).