Once upon a time, there were sixteen little bugs living in a vegetable garden next to a river. These tiny bugs didn’t eat much, but the owner of the garden didn’t want to share any of his vegetables with insects. So he bought a can of pesticide from the store. This poison was a fine white powder that he sprinkled on all the plants in his garden.
Each one of these tiny bugs had a very small mouth and could take only one tiny bite. However, with each tiny bite of vegetable, each bug swallowed one small dot of poison. Since these bugs were so tiny, this one small dot of poison was enough to kill them and they all fell over dead.
Just then, a group of eight larger insects, who just loved to eat other insects, walked by. Imagine their surprise and glee when they saw sixteen of their favourite bugs lying on the ground. These larger insects did some quick arithmetic and figured out they could each eat two of the small insects. What a feast! First, they each ate one bug and it was delicious. Little did they realize though, that each time they ate a bug they were also eating a dot of poison. However, since they were larger bugs, that one dot of poison wasn’t enough to kill them.
Maybe they felt a little sick but that didn’t stop them from eating a second small bug, which of course contained another small dot of poison. That did it! Now the larger bugs fell over and died.
Just then a strong gust of wind blew through the garden. It picked up the dead bugs and blew them into the river.
Swimming just under the surface of the river were four little fish looking for their midday meal. When these eight large bugs landed on the surface of the water, it took only a second for each fish to gobble up two of the large bugs, which don’t forget, had two dots of poison each. This means that each little fish ate four dots of poison.
Now these dots of poison weren’t enough to kill the four fish, but they were enough to give them stomach aches and make them swim a little slower. Because the little fish were swimming slowly, it was easy for two big fish, a male and a female, to quickly overtake them.
Each big fish swallowed two small fish. Now, each small fish had four dots of poison in it, and each big fish ate two small fish. So each large fish got eight dots of poison. This wasn’t enough to kill the large fish or even make them feel sick. But it was enough to make the male fish notice, in days to come, that he didn’t grow as big as his friends. The female fish began to notice that she wasn’t having as many babies as her friends.
One day, the man who owned the vegetable garden decided to go fishing. He threw his line in the river, and being the clever fisherman that he was, he soon caught both these large fish. “What a fine meal,” he thought to himself as he prepared and cooked the fish. And every bit was delicious! But, since each of these fish had eight dots of poison in it, the man ended up eating sixteen dots of poison. And it all started from that poison he had put on the garden a long time ago.
Now, these sixteen dots of poison weren’t enough to make the man die, or make him sick or even make him grow more slowly, but what might happen if he had eaten more fish or if he went fishing everyday and ate the fish containing the pesticide? Could he end up like the bugs or the fish?
This story is adapted from School Garden Manual, by Marny Smith, 1989, published by Save the Children, 54 Wilton Road, Westport, Connecticut 06880, U.S.A. The purpose of the story is to help people understand how pesticides and other poisons build up in different insects and animals along the food chain.