An incredibly dry spring season in the North East part of the United States is boosting the Gypsy moth population, and people are being forced to deal with more than they are used to. The hungry insects have defoliated millions of acres of trees, and people have been cleaning an equivalent amount of fesses from cars and roofs.

The insects have completely defoliated millions of forest acres, and the sheer numbers have even disrupted activities at airports. People in the United States, especially in the Northeast, have been facing the same pest ever since it was introduced in the late 1800s. To boost the silk market in the country, a group of scientists brought the insects from Europe, but in the end, it was not profitable.

Some of the moths broke free and made themselves comfortable. In fact, absent the natural predators they had back at home, Both Asia and Europe, they thrived eating everything in their path. Image Credit: Uwex
Some of the moths broke free and made themselves comfortable. In fact, absent the natural predators they had back at home, Both Asia and Europe, they thrived eating everything in their path. Image Credit: Uwex

The moths themselves are not the problem, but when they are in their larval form, they are a real threat to unprotected echo systems. As any other caterpillar, they eat in excess until they reach the cocoon stage. In little numbers, they are nothing to worry about, and they have many natural predators back at home.

But in the United States, the story is different, they are aliens, and they don’t have natural enemies. As a result, the Gypsy moth population grew unchecked and became a real problem in the area. They prefer eating leafs from sweet trees, mainly oak trees which are critical for the economy of local communities.

The government expects the number of Gypsy moths to increase in the coming years

In the beginning, the Gypsy moth population was established in Main, Vermont, New Hampshire and Massachusetts, but that has changed over the years. According to the USDA Forest Service, they are spreading to the west and south at a rate of 21 km per year. They add if they remain unchecked, they could go as far as Arkansas by 2025. The experts have noticed the insects move in many different ways.

Scientists working with the federal agencies say that stopping the spread is totally impossible. Instead, they can slow down the pace at which they are doing, hence reducing the impact they have on the environment.

The authorities have identified the zones where the Gypsy moths live in high numbers which are the primary targets for suppression. However, they have also found isolated nests where the animals thrive in little numbers which indicates alternative spreading methods such as high winds or even human intervention.

The fact that scientist has confirmed the presence of Asian Gypsy Moths proves human intervention. Officials believe they were smuggled into the country and ended up in private collections or laboratories from which they escaped.

 It's worth noticing the first lot introduced in 1868 only had European moths. Image Credit: Ontario Moths
It’s worth noticing the first lot introduced in 1868 only had European moths. Image Credit: Ontario Moths

Gypsy moths are the worst pest existing in the United States, and local communities have tried to get rid of the problem using pesticides. The government realized that was not very efficient and authorized the creation of groups that specialize in suppressing the moths. In fact, in some states, there is a hotline to report the presence of the insects, so the authorities can go and clear the area. In spite of all these efforts, the numbers have steadily increased over the years.

Scientists had temporary success in controlling the pest

During its larvae state, gypsy moths have a lot of spikes all over their bodies which make it discourages local fauna from attacking them. And even though experts realized cuckoos and some species of mice preyed on the caterpillars, it was not enough to control their numbers.

That is why, in 1989, they introduced an Asian fungus that eats the larvae inside out, and it worked. After the fungus established in the area, the number of gypsy moths notably decreased until recent years when the climate started to change. The raise in temperature eliminates the humidity from the air which results in an overall reduction of fungi.

However, scientists are thinking of taking a different approach based on bio-engineering. Thousands of fruit crops were being ravaged by a pest of medflies in Australia, and there was little farmers could do. But in 2015, a British company grew their medflies modifying their DNA to make them infertile. Then, they released them into the wild where they started to mix with the current population. As a result, the number of medflies rapidly decreased, and the crops were saved without using a single drop of pesticide.

It is unclear if the United States will try to do something similar, but the government has been funding laboratories country wide to find a more permanent solution without having to destroy native fauna or flora.

Source: Forest Service