Red-And-Blue
Poison-Arrow Frog
The red-and-blue
poison-arrow frog's jewel-like color stands out from the rich
rainforest vegetation as a warning that it is one of the most poisonous
animals on earth.
For centuries, the
poison-arrow frog has provided South American Indians
with poison for the tips of arrows and blowpipe darts. For
predators,
swallowing a frog means certain death, and even licking one can prove
fatal.
|
The newly
hatched young attach
themselves to the female's moist back.
HABITS
Like all amphibians, poison-arrow frogs must stay moist to survive.
The red-and-blue species lives in Costa Rican rainforests. The
constantly steamy, wet environment reduces the frog's need for streams and
pools.
It forages
through the rain-soaked leaves and vegetation for small insects such as
ants and spiders. The poison-arrow frog moves in short hops and
rarely stays still. Adhesive pads on its toes allow it to climb
agilely to search for prey.
Its vocal sac
fully extended, a poison-arrow
frog croaks a territorial claim.
POISON-ARROW FROG & MAN
The Choco
Indians of western Colombia developed the technique of using this frog to
poison the tips of arrows or blowpipe darts.
The Choco use poison
from three species. With the deadliest frogs, the tribesmen pin a frog to
the ground with a stick and wipe their arrowheads on its skin. Less
poisonous species are warmed over fires on skewers to make them excrete
large quantities of poison, which is concentrated for use.
Today
the Choco use poison darts or arrows for hunting small game, but in the
past they were used in wars with other tribes in the forest.
|
BREEDING
Many frogs lay large quantities of eggs in water and leave them alone.
Fish eat the newly hatched tadpoles, and few survive to develop into
adult frogs. The poison-arrow frog breeds in a different way that
ensures the tadpoles' survival.
After a courtship ritual of calling, chasing and wrestling, the female
lays four to six eggs. The male then fertilizes the eggs.
The newly hatched tadpoles climb onto the female's back, and she carries
them to the water. Sticky mucus holds the tadpoles on tight and
keeps them moist during the several-hour journey.
Instead of a pond or stream, the red-and-blue mother places her tadpoles
in tiny condensation pools in the centers of tropical plants.
The female puts one tadpole in each plant, feeding them each week by
placing unfertilized eggs in the pools. Fed on this nutritious
food, the tadpoles grow into adulthood.
Males wrestle for mates;
their poison is for predators.
DEFENSES
Some frogs protect
themselves from larger predators such as snakes and hawks by secreting
mild poisons from the skin to make themselves taste foul.
The poison-arrow
also uses this tactic, but its skin gland secretions are lethal. A
predator faces certain death if it swallows a poison-arrow frog, and
even licking one can often prove fatal.
These frog poisons are the most powerful animal poisons known. As
little as two micrograms of its poison can kill an adult human − and each
frog contains nearly 200 micrograms.
Because the poison-arrow frog is too small to be seen by some animals,
its brightly colored skin makes it more noticeable and acts as a
warning to predators that the frog is deadly prey.
Consequently, fewer frogs are eaten during the day, when predators can
recognize them as dangerous.
|