Dendrobates pumilio

Jamie George
Last update: 17 August, 2002

Dendrobates pumilio is a small 18 - 24mm poison-arrow frog which lives in the lush rainforests of Costa Rica, Nicaragua, Panamá and its neighbouring islands.

D. pumilio Isla Colón
Photo Peter Draper

Although it occurs in a vast range of colours (see below), that most commonly seen in captivity is the one known as the ‘blue leg’ or ‘blue-jean’ form found in both Costa Rica and Nicaragua. This has intense strawberry-red back with blue legs. This has given D. pumilio its common name of Strawberry poison-arrow frog. However, the D. pumilio from the islands off the coast of Panamá can be orange with black spots, red with black spots or white with black spots. All three morphs occur on one island! There are other morphs from the islands of Cayo Nancy, Shepard, Colón, Bribrí, San Cristóbal and Isla Popa. These can be solid blue, brown, orange, green, black, green and yellow with brown spots, orange with black spots - the list goes on. Several colour forms occur in Costa Rica. For example, the form associated with the area of Puerto Viejo on the Caribbean Coast is a solid red with a small, blue patch on the chest. Further inland in the area around La Selva biological station the typical ‘blue leg’ form is most predominant.

Female D. pumilio are always a little larger than male D. pumilio and have a more rounded shape with smaller toe pads. Males are smaller, have a more slender appearance with bigger toe pads and have a vocal sac. The presence of this vocal sac makes some forms of D. pumilio easy to sex, as it appears as a dark-blue patch on the throat, a feature missing from females of the same colour variety.

The call of male D. pumilio is a long, high-pitched 'epp-epp-epp' sound, which he usually makes while displaying on a bromeliad leaf. If a gravid female is nearby, she will approach the male and stroke his back with her front feet. The male will then signal to the female to follow him. The pair will now look for a suitable place for the female to lay her eggs. Female D. pumilio will often lay their clutches of eggs on smooth bromeliad leaves or on the ground in the leaf litter.

Once the clutch of four to eleven eggs has been laid, the male will care for the eggs by periodically sitting in a very shallow water pool and then returning to the egg clutch to sit on them in order to keep the clutch moist. In addition, will often moisten the clutch with his urine. After ten to twelve days the tadpoles will hatch and their care is now taken over by the female, who carries the tadpoles on her back to deposit each one individually in the water-filled funnels of bromeliads.

D. pumilio near Limón, Costa Rica
Photo John Skillcorn

Over the following months the female returns to the bromeliads often to feed the tadpoles with infertile eggs that she produces especially for this purpose. This feeding of ‘food eggs’ to the tadpoles will continue until their metamorphosis, at which point tiny 10mm-long froglets will hop out of the bromeliads and into the leaf litter. They immediately begin searching for tiny food items like springtails.

D. pumilio Isla Popa (left) and Bastimentos (right)
Photo Paul Armitstead

D. pumilio typical form from near
Guápiles, Costa Rica

When keeping D. pumilio in captivity they should be provided with a vivarium filled with as many bromeliads as possible. This will provide them with a lot of cover to make them feel comfortable in their environment as well as providing them with prospective sites for tadpole care.

Most D. pumilio in the hobby are wild-caught, the main reason for this being that D. pumilio is comparatively difficult to breed in captivity being an ‘egg feeder’ (along with related species such as D. histrionicus, D. lehmanni, D. speciosus and D. occulator.)

A substrate of Oak leaf-litter is best to mimic their natural environment. The frogs will also eat a lot of tiny insects that live in the leaf litter – many of these are hardly visible to the human eye. A temperature of between 23-28°C (74-82°F) is best with humidity kept above 75%.

D. pumilio should be fed as big a variety of food items as possible, but the most popular food organism for all poison frogs is Drosophila, the fruit fly. These are easy to breed yourself with banana, oatmeal and yeast granules. Newly hatched crickets are also an excellent food source for D. pumilio, along with aphids which, during the summer, can often be found in vast numbers on the underside of sycamore leaves. Other small invertebrates can be collected at this time and fed to your frogs but always be aware of the risk of parasites when feeding food collected from the wild.

D. pumilio Isla Popa
Photo Peter Draper

So, given the right conditions and a varied diet D. pumilio should, with luck, breed in captivity. However, this species of poison frog is not for the beginner. Most of those that come available are probably wild-caught and hence infested with internal parasites, for which they will need appropriate treatment. Also, the fact that they are specialist egg feeders can leave you frustrated when attempting to breed them.

Bibliography
Hesselhaus, Ralf  Poison-arrow frogs - their natural history and care in captivity.