The number of California monarch butterflies has been alarmingly decreased in the last two years as said by a team of environmental researchers. These butterflies migrate along the California Coast. Recently, the Xerces Society recorded about these butterflies. They recorded less than 30,000 butterflies, which means it is an 86 % lesser as compared to 2017. In 1981, more than 1 million monarch butterflies were recorded as per the reports of the San Francisco Chronicle.
The Xerces Society conducted annual counts of these butterflies but was not sure about why the numbers dropped. A study done by researchers at Washington State University, in the year 2017, said that these species can become extinct if nothing will be done to save them. As per the scientists, these butterflies may have reduced in numbers because of a high number of pesticides and herbicides on their migratory routes. The scientists also say that the climatic changes could also be the reason. Effects of the historic drought, spring storms, season fires, etc. are a few climatic issues that may have affected these species. The monarch butterflies rely on milkweed plants and flowering plants for laying eggs and nectar respectively. But in California, many of these plants have been eradicated. For saving these species, we should think on both factors- climatic changes and the eradication of the plants necessary for their life.
Other researchers from Stanford University and University of Michigan found that the carbon dioxide from factory exhausts and cars affected the butterflies. The caterpillars use a natural toxin in the milkweed to fight parasites. The carbon dioxide has the capacity to reduce this toxin. The monarch butterflies are usually spotted from November to March on the California coast. The decline of these butterflies was first noted in 1997. Today’s number of these species is much alarming. It shows that the butterflies may not survive even for a year. There is still a chance to save these iconic and beautiful species. We must act immediately on this.