The farmer who didn't think
On a far away citrus farm, a farmer had planted 50 orange trees. The oranges produced were exceptional and all the town’s folk would comment on the excellent quality. The farmer also had wild birds that lived nearby. Every morning the farmer would wake up to the wonderful whistling of the birds. One day the orange trees started to die. The farmer kept a count of the average number of leaves on each tree and he plotted the number on a graph.

When walking through the trees the farmer noticed hundreds of grubs on each tree. They were ugly, with spikes and chewed through the leaves with a ferocious appetite. The farmer quickly sprayed the trees with insecticide and after a number of days noticed that the number of leaves on each tree started to increase. On the 16th day the farmer woke to a deafening silence, he would never hear the birds again.

Gather as much information from the graph and explain why the birds never appeared again. Use the words FOOD WEB and ENERGY.