Poison-Arrow Frog
|
PHYSICAL CHARACTERISTICS:
The Poison-Arrow frog, Dendrobates azureus, is among the most handsome members of any collection of herpatiles. While nearly all frogs and toads have at least a trace of poison in their skin glands, toxins are most highly developed in some of the poison-arrow frogs. While most are not potent, a few species deploy some of the most poisonous biological toxins known. These toxins have long been used by Indians in the poisoning of their arrows to produce quick death in animals.
There are 116 species of Poison-Arrow frogs whose colors vary from bright green, red, pink or gold with darker spots and stripes. These bright colors warm potential predators, and birds which normally eat frogs, to avoid certain species.
Most species can be recognized by the presence of a pair of plate-like scutes on the upper surface of each toe and fingertip.
 Dendrobates leucomelas |
DISTRIBUTION and HABITAT:
These brightly colored terrestrial frogs are found in the rain forests of Central and South America, from Costa Rica to southern Brazil. They live in dense vegetation with high humidity and running water.
BEHAVIOR:
Both sexes defend territories against frogs of the same and other species. Aggressive behavior includes calling and color changes (in males), postural displays, chases, attacks and wrestling (both sexes). Prolonged fights are most likely to occur between frogs of the same sex, but sometimes males and females wrestle.
DIET:
Poison-arrow frogs have a disadvantage in their feeding habits. They require the tiniest of insects which may sometimes be difficult to procure. They eat ants, termites, small insects, and small spiders.
REPRODUCTION and GROWTH:
Eggs are laid in February or March and throughout the summer. The
male selects a flat area (bromeliad leaf), which he clears off while calling to the
female. Both male and female clean and moisten the area where eggs are to be laid. The
male tends to the eggs, making sure they do not dry out.
Eggs are 2 mm in diameter. Clutch size is from 1 to 14 eggs, averaging 7. Incubations is 10 to 14 days.
About four days after the eggs begin to hatch, the tadpoles swim up the male's legs onto his back. He goes into the water, and the tadpoles swim off him. Approximately 2 months after hatching, the frog- lets move out of the water.
Striking colors warn potential predators not to eat the small poisonous frogs of Central and South America. Some edible species also gain protection by mimicking the conspicuous coloration of their "poisonous cousins."
Amerindians hunt birds and monkeys with darts and arrows that have been coated with the frogs' skin secretions which are highly potent nerve toxins.
