Boy, the forest has been noisy at night! What with all the racket produced by the katydids, crickets and grasshoppers, it's as if the forest is filled with musicians, all striving to be heard above the surrounding din. What's the purpose of all this noise? As usual in the natural world, it all has to do with mating.

Often people ask me why the noise of the grasshoppers and crickets becomes much louder towards the end of the summer. The answer has to do with their life cycle. Most insects, including crickets and grasshoppers, will die in the fall with the arrival of the first hard frosts. If their mating season was successful, they will not have died in vain. The females of the species leave behind eggs that will ensure the continuation of their kind for another generation. The eggs, deposited on the ground or under leaves, tree bark and tree litter, will lie dormant all winter long. Even under feet of snow or exposed to howling winter winds, the eggs do just fine. With the arrival of warmer weather in the spring, the young insect finally emerges from the egg.

The eggs are minute in size, as is the baby grasshopper. At this stage, it is simply an eating machine. As a baby, it is of course not capable of mating. This explains why we don't hear much insect noise early in the summer. Occasionally, I will find an immature katydid early in the season. I'm always struck by how tiny they are, compared with the huge size of fully mature adults.

After a number of weeks of eating and molting, followed by more eating and molting, the insects are finally ready for mating activities. The time varies from year to year, depending on weather conditions, availability of food sources and other factors. This year, the katydids began calling in this neck of the woods a good two weeks earlier than they normally do. Despite this variation in the onset of mating, August is always the height of their frenetic activity.

By this time of the year, as soon as the cicadas quiet down for the night, the thundering chorus of the katydids resounds throughout the forest. They're joined by the more melodic crickets and the occasional piercing buzz of the cone headed grasshoppers. On a typical night, it will all last until around 3 a.m., at which time the exhausted insects are ready for a good day's sleep.

The sound of the katydids is one of my favorite in all of nature. We are fortunate to hear them here, as Adams County lies near the northern part of their range. While visiting Elk County a few weeks ago, I was struck by the utter silence of the night. Even in the deepest wilderness, there was not a single katydid to be heard.

I find it interesting how the sounds of insect mating calls are so comforting to humans. The chirping of the crickets has inspired many poems and songs in various cultures. The katydids lull me to sleep. Contrast that with the mating calls of humans. Imagine the streets of Gettysburg filled with young men bellowing over and over again, "Hey baby, I'm over here, look at me!" And you thought Bike Week was noisy!