Some of the most recognizable insects on the planet, the monarch butterflies could very well be considered true royalty. Aside from the fact that they look majestic, their yearly migration during which they travel for two thousand miles from Canada to Mexico and then back is one of the most impressive animal migrations ever.
And seeing as the scientific community finally understood exactly how the generations of butterflies manage to fly across three countries without getting lost, they are now excited to find out more about the creatures. And finding out exactly why their numbers are declining is of top priority.
According to a new study from the Cornell University, lack of food and habitat changes endanger monarch butterflies. But while it was previously believed that milkweed, the food the creatures eat during the summer, was the one that was lacking, it turns out that the problem runs much deeper.
Professor of evolutionary biology and ecology at the Cornell University and lead author of the study, Anurag Agrawal, had this to say about the main culprits behind the decline of monarch butterfly numbers:
Thanks to years of data collected by World Wildlife Fund and citizen scientists across North America, we have pieced together the monarch life cycle to make inferences about what is impacting the butterflies.
Given the intense interest in monarch conservation, the blame being put on herbicide use and the national dialogue about potentially listing monarchs under the endangered species act, we have to get the science right.
So yeah, aside from climate change being responsible for the steady disappearance of the monarch’s favorite summer food, milkweed, most of the other factors driving the butterfly populations down are also man-made. From pesticide and herbicide use to genetically modified crops, and even the addition of invasive species, all of these factors are caused by mankind and are driving the butterflies to extinction.
Still, the creatures are doing better than they were two years ago. In fact, two years ago the monarch butterflies were at their all-time low, with their numbers being six times lower than they are today. Increased efforts and funds aimed at their conservation helped the tiny insects come back a little bit.
This means that further efforts would probably help preserve the butterflies even more, if only further efforts were being made. As the situation currently stands, many scientists are of the opinion that the population has dwindled so far that there are few chances of the creatures actually coming back in force.
While an estimated number of 140 million butterflies spent their winter in Mexico this year, that is but a fraction of what their numbers used to be in the past. As recently as the late 1990s, the monarch butterflies numbered at a few billion. Now, slightly more than 150 million are remaining.
Image source: Wikimedia