excerts from

Poison-Arrow Frogs,
Their Natural History and Care in Captivity

by Ralf Heselhause



Chapter 10, The Genus Dendrobates



Dendrobates auratus

Description

The auratus is one of the species of Dendrobates richest in varieties. In size and colouring as well as in habits there are great differences. It is between 2.5 cm (1 in) and 6 cm (2 3/8 in) long, according to its region of origin. Already over 15 colour forms of this species are known.

The home of one variety is the Pacific island of Tobago, belonging to Panama. These frogs, which are about 3 cm (1 1/8 in) to 4 cm (1 1/2 in) long, have yellow-gold stripes on a brown background. Many have a lighter brown background that emphasizes the golden effect even more. Partly because of the dry periods characteristic of the natural environment of these frogs, they are very robust and undemanding.

Among the most beautiful and most commonly imported of D. auratus are those from Costa Rica and western Panama. The glow in green and black, with bands of green irregularly distributed over the basic colour of varnished black - the proportion of green depending upon which population the variety comes from. The size of these very shy frogs varies according to the region of origin, but they are between 4 cm (1 /12 in) and 6 cm (2 3/8 in) long.

The smallest variety of D. auratus, 2.5 cm (1 in) long, lives in the Panama Canal zone. These frogs, also known as Colonauratus, have the same green-black colour scheme, but they display only a few small green spots on a black background. They are very active, quick frogs, which are rather shy. From the Pacific side of Panama frogs with blue markings have only recently become known. These attractively coloured frogs are basically black, with intense blue markings ranging from light blue to almost violet. Within this population are also the exceedingly rare uniformly blue frogs. This quiet and amiable frog is among the larger of the D. auratus frogs - it reaches a good 4 cm (1 1/2 in).

Many other varieties of D. auratus exist - there are albino forms and brown, white, or yellow striped, dotted or single-coloured specimens. The range of different forms is so large that they cannot all be discussed here.

Distribution and habitat D. auratus inhabits large regions of Central and South America and is to be found from southern Nicaragua to Costa Rica, from Panama to Columbia. In addition, numbers have been introduced to the Hawaiian island of Oahu.

As a rule D. auratus inhabits the dryer regions of primary forests. The frogs live in pairs or in small groups on the ground, near large trees. Their habitat always includes a layer of dry large leaves on the jungle floor. They live at sea level as well as at around 800 m (2,600 ft).

If their habitat has already been cultivated, they prefer to live in cocoa plantations, where the fallen cocoa-plant leaves on the ground supply ideal places for hiding and depositing eggs. Moreover, around the time of the cocoa harvest, the rotting fruit attracts large numbers of insects, which form an excellent, easily caught diet for the frogs.

In large areas, especially in Panama, the habitats of D. auratus have been completely destroyed. Very often it is only narrow strips of vegetation along river courses that enable a few varieties to survive. The blue D. auratus is one of the colour forms living in such an area. The homes of these frogs lie like oases in the midst of dried-up landscapes and it can only be a matter of time before the last of these frogs has disappeared.

Care in the terrarium All varieties of D. auratus are easy to keep and breed in captivity. The size of the terrarium depends of course, on the number of frogs you intend to keep - remembering that it is possible to keep D. auratus in company with other poison-arrow frogs in a community terrarium. As D. auratus lives mainly in two dimensions, scarcely climbing at all, a terrarium has to be chosen with as large a floor area as possible. Two to five animals should form a breeding group. The terrarium will most closely approximate to their natural habitat if the floor is completely covered with oak leaves. The only plant needed is Anthurium christallinum, whose attractive leaves and luxurious root system afford an interesting spectacle after only a short time. If you want to mix these D. auratus with other frogs, their needs will also have to be catered for. A tank measuring 90 cm (3 ft) in length, 60 cm (2 ft) in width, and 90 cm (3 ft) in height is suitable for four auratus, four P. lugubris, and five to ten D. pumilio, which all live together even in the wild.

Given temperatures of 20 to 28 degrees C. and high humidity, D. auratus will have offspring very soon. The frogs will use halved coconut shells as well as the leaf layer. The egg clutches contain six to eight eggs. As not all parents look after their young, the clutches should be tended artificially - caring for the larva is no problem.



Dendrobates azureus Blue poison arrow frog

Description D. azureus is a rare species with a small, limited area of distribution. Do not try to keep this species in a terrarium unless you are sufficiently experienced to breed it successfully.

The blue poison-arrow frog, with a size of 38 mm (1 1/2 in) to 45 mm (1 3/4 in), is among the larger species. It has an attractive appearance, with a glowing blue net or dot pattern on a black base. Some specimens are mainly blue. As in D. tinctorius, which can be crossed with this species, the fingertips of the males are flattened.

Distribution and habitat D. azureus inhabits the Sipaliwini savannah in Surinam at levels between 300 m (1,000 ft) and 400 m (1,300 ft). They are known nowhere else. Here they are to be found in small remnants of jungle in the savannah. They live on the ground, beside small streams flowing through the jungle islands. Temperatures are between 20 C. at night and 27 C. in the daytime.

Care in the terrarium D. azureus has been bred successfully with increasing frequency and so, thanks to committed terrarium keepers, a considerable stock of terrarium specimens has been derived from a few imported animals. Reports of successful breeding can be read, for example in Kneller (1982b).

These glorious blue poison-arrow frogs show no shyness in the terrarium, so their mating behaviour can be observed quite easily. As a rule the female is the more active during mating. A female willing to mate will nudge the male in the side and stimulate him by stroking his back with her front legs. The male seems to find this impossible to resist and the two frogs finally disappear into their chosen spawning chamber. Usually it will not be long before the clutch of four to six eggs is deposited. The entire mating procedure is carried out very quietly - D. azureus males are no vocal artists. Their occasional subdued croakings, no more than a quiet buzzing, can hardly be heard outside the terrarium. The development of the clutch up to emergence of the larva will take about 18 days at water temperatures around 22 C. The best container to use is a Petri dish. A drop of fungicide should be added to the water, which should be so shallow that the clutch is not completely covered.

The larvae should be raised in solitary confinement because of their aggressive behaviour. They will reach metamorphosis after 10 to 12 weeks if fed with flaked food and gnat larva, and will turn into young frogs about 18 mm (3/4 in) long.



Dendrobates fantasticus

Description The most remarkable feature of D. fantasticus is its red head, which clearly stands out from the lacquered black of its back and extremities. For this reason the name I have suggested for the species, the red-headed tree frog is probably quite appropriate. On its red head it has an irregularly shaped black mark, a kind of crown. The shiny black of its back and belly is broken by cream-white stripes. Young animals do not show the marked contrasts between red and black of the adult - they have red patterns on the backs to begin with, which they lose during the first few weeks of their lives. Distribution and habitat According to Kneller (1982a, 1983), D. Fantasticus lives in the forests of the eastern mountain ranges of the Peruvian Andes, in the province of San Martin. It inhabits by preference shady primary forests at heights of 500 m (1,600 ft) to 800 m (2,600 ft). Kneller was able to observe it in its natural habitat. According to his observations, the frogs are purely tree dwellers, as they were found always at least 1.4 m (4 ft 6 in) above ground level on different tree trunks. Kneller also observed a few specimens on high leaves, where they appeared together with D. imitator (which Kneller described at the time as D. reticulatus.)