It is always nice to visit a National park and see animals such as Monkeys and
As we quietly stroll amongst the giant trees and along the trails our eyes and ears ever alert for that chance encounter with a Jaguar or a Tapir. It rarely happens though!
The forests offer big expectations to the casual visitor. The guidebooks and
promotional materials are brimming with descriptions of all the wonderful and
colorful animals that are just waiting to be photographed.
This can sometimes lead to a sense of disappointment for some of us. Its true,
all these fantastic creatures live out their daily lives here in the Tropical
forests, the Macaws and the Toucans, Humming birds and Spider Monkeys, Pizotes,
Armadillos, Ocelots and Anteaters, the list goes on and on. It’s also true that
we are, perhaps, more likely to see these animals here in Costa Rica than in other
destinations, but we are not visiting a zoo where animals are confined and on
display. It’s a jungle out there!
If you happen to be a forest denizen, chances are, you are either trying your
best to eat someone or you are trying your best not to be eaten. Bearing this
in min, the casual visitor will find that most animals are not out and about,
singing and dancing, and generally drawing attention to themselves, and understandably
so. If you want to live long, don’t be seen, that’s the rules of the jungle.
Thankfully, this rule does not really apply to us humans. We are too big to be
eaten by most forest residents, however, we are often seen as a potential predator
and hence, something to be avoided if possible.
There is however, one group of animals that are always present and seldom run
away from us when we approach. If we stop to really look at them and watch what
they are doing with their lives, we may not be so disappointed when we don’t meet
that puma we had hoped to see.
It is the humble ant which we are talking about here, and out of the 9000 varieties
in existence there are three very common species which are positively fascinating
when a little of their lifestyles is understood.
During the 1940s, a revolutionary named Pepe Figurez forcibly took over the Costa
Rican government sending his political enemies fleeing over the Nicaraguan border
for fear of their lives. One of his first acts as head of state was to abolish
the army. To this very day his legacy is evident in the absence of a national
fighting force, but as we will see, this truly is not the case.
A massive army of ruthless killers, camped out in the forests of the lowlands
is still very much in operation. They rampage across the country in their thousands,
armed with chemical weapons. They don’t understand the meaning of mercy and they
never take prisoners. Standing in unshakable solidarity, they move in unison,
striking fear into the hearts of those that know them. No one will dare oppose
them. They butcher and eat their victims, this army of sisters.
While in the forest we notice a sudden exodus of creatures of all shapes and
sizes moving along the leaf litter. It appears that they are all heading in the
same general direction and they are doing so with great haste.
Giant Cockroaches, Beetles, small Lizards, Toads and Frogs, big Spiders, grasshoppers,
Crickets, Centipedes and Scorpions are all running along together. It can be quite
alarming if our party happens to be directly in their line of travel.
One can be excused for believing that all the creatures of the forest have united
and are coming after us as if acting out a script from a nightmare Hollywood B
Some distance further back we can hear an omnipresent hissing noise, it’s reminiscent
of the sound made by very gentle waves lapping on a sandy beach. It’s not emanating
from one specific point though; it’s just generally coming from the ground.
This is the sound made by tens of thousands of little feet stampeding across
the drying leafs on the forest floor. To most of the non-flying animals that live
here, this is the sound of approaching death.
Even to a creature as relatively large as us human beings, the sight of a raiding
swarm of army ants is nothing short of awesome. Every centimeter of ground is
blackened by a seething mass of insects. They advance steadily forward, searching
under every leaf and stone for hapless prey, climbing up every treelet and plant
to capture caterpillars and bugs. They relentlessly pour themselves down into
every hole to decimate other species of ants or burrowing spiders such as giant
The advancing wave of ants can be over thirty meters wide. Metaphorically speaking,
no stone is left unturned.
Army ants devouring a scorpion
Web spinning spiders remain relatively safe, other species of arachnid who don’t
make webs hang precariously from a single thread, suspended in mid air hoping
to ride out the storm. There are a few hairy caterpillars, armed with bushy defenses
that prevent the ants clasping jaws from gaining a purchase, but in general, once
surrounded, most animals are condemned to be paralyzed by a potent chemical sting
and butchered on the spot by a hundred powerful mandibles.
They are like an efficient factory. The meat is cut up into manageable pieces
and then carried back to base camp to be fed to the colony’s developing larvae.
Army ants are carnivores’ par excellence.
They are such voracious predators that should they have a permanent nest, as
most other ants do, they would soon deplete the area of prey. This necessitates
a nomadic lifestyle.
They set up temporary home basis, which are constructed out of the living ants
themselves. They cling to each other using their hooked feet, forming seething
walls of protection for their queen and the colony’s youngsters.
Now we should return to the head of the swarm, back to where the ground is still
visible, back to where the other animals are running for their lives. If we look
up into the lower branches we now notice that there is a great many excitable
and noisy birds flitting around.
These birds are not avoiding the ants, not at all; they actually seek them out
and take advantage of the mayhem they cause. The birds swoop down and pick off
the refugees as they run blindly away. There is one family. Aptly named the ant
birds that owe their existence to these ants. Because colonies of army ants are
not always out hunting, these birds will closely monitor the movements of several
different groups within a territory and decide upon which one to follow for that
Robber flies engage in the same activities but on a smaller scale, they pluck
victims from the air and stab them with their hollow dagger like mouthparts.
Capuchin monkeys, Cross-billed hawks, Parasitical flies, and wasps all take advantage
and add to the slaughter. We can only be thankful that our size excludes us from
a fate such as this.
The next group of ants are a more genteel bunch, in fact we can aptly describe
them as peaceful farmers, minding their own business and tending their crops.
The leaf cutter ants are a charismatic bunch. They resemble an overcrowded yacht
race, moving along in organized columns, each one holding a green leafy sail above
Why are they carrying these neatly cut pieces of greenery down into their giant
underground nests? They must eat leafs, surely.
In fact, once the leaf fragments are taken from the tree they are chewed up into
pulpy mulch by a special cast of smaller worker ants. On this mulch grows a unique
kind of fungus, the ants staple diet.
The fungus is a fussy and fickle thing. It will only grow at a precise temperature
in a precise humidity on a precise medium. The ants provide these conditions to
perfection and even tend their fungal crops with a protective microbial secretion
that they rub off from their chests. Without this protection, the crops can be
lost to an enemy fungus, which destroys the edible variety. If this should happen
the colony will perish.
The fungus grows only in leafcutter ant nests and nowhere else. Without the ants,
the fungus could not exist, and vice versa, and without the microbes, which are
also life forms, the whole system would collapse. Scientists call this sort of
interspecies dependence, symbiosis.
Apart from the queen, virtually all the other members of the colony are sterile
sisters, but at a certain time of year, as with all ants species she will produce
winged reproductive daughters. It is the job of this special caste to fly out
into the world and found new colonies, but before they depart, each one will journey
down to the underground gardens and pick up a mouthful of fungal spores. It is
this important little sample that will be the foundation for her very own colony.
A single pioneering female, after mating, will burrow down into the earth with
her precious cargo of fungus. She will lay her first fertilized eggs and if lady
luck shines on her, she will be the first queen of a colony that can number in
the millions. They will build a nest up to fifteen meters wide and three meters
deep that will possibly survive for centuries.
Our last species of ant is another example of symbiosis. They are known as Acacia
ants, named after the small tree with which they form their dependant relationship.
The tree produces very large hollow thorns, perfect houses for little ants. These
insects are hyperactive little fellows. They run around every inch of the plant
and will fearlessly attack anything or any one who tries interfering with their
They may be small but just like their close cousins, the wasps, they are armed
with mighty powerful stings, and believe me, they know how to use them.
It’s not just the home that they are defending though; it’s their bread and butter
too. If we look very closely at the base of each delicate and feathery leaf, we
will see a very small pore like structure. These are called nectaries and serve
to feed the colony of ants with a sweet energy rich drink.
We may also see tiny yellow balls growing from the newest greenest leafs. The
ants will likely be tensing or harvesting intensely around this locality. These
little balls are packed tightly with all the nutrition that a happy growing family
of ants could need.
In return for three square meals a day and a cozy hollow thorn in which to sleep
at night the ants act as personal bodyguards to the tree. Nothing dares graze
on the tender juicy leafs. The ants even go as far as making a clearing around
the base of the plant itself. All other plants, potential competitors for light
and soil nutrients, are snipped and trimmed and all alien seed are carted off.
This clearing of the ground may also serve the plant as protection against fires.
So as we can, It’s not just all those big forest animals that can be intriguing
and exciting. We should spare some time for the smaller characters of Costa Rica
and get the most out of the National parks that we visit.
No doubt we will return to our homes and hotels with a few mildly painful red
and raised lumps on our bodies from interacting with these excitable little creatures,
but when somebody asks us “what did you see today on your walk in the forest”
we will be able to keep them enthralled for hours with our tales from the bush.
If we miss seeing a Jaguar because we were carefully following a trail of foraging
ants, we shouldn’t get too upset, after all, if you believe what the guide books
tell you, they are everywhere. No doubt, we will se one tomorrow.
Dale Morris and his wife Sasha left Great Britain 11 years ago. He has written
numerous articles about wild animals in Costa Rica since 1997. Dale works as a freelance nature writer and photographer and his work has been
published in BBC Wildlife, Geographical and Global Adventure and regularly contributes
to ‘Costa Rica Outdoor’ Magazine and Asahi weekly in Japan. Together, Dale and his wife have worked in Australia, Thailand, Indonesia, Nigeria,
Kenya, Tanzania, Costa Rica and Scotland and have been attacked by mosquitoes,
killer ants, monkeys, chimpanzees, jaguars, fish with sharp teeth, scorpions,
bees, bears, giraffe, elephants and drunken Scotsmen during that time.
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