A recent study of the monarch butterfly (Danaus plexippus) population in California showed a catastrophic decline in numbers. If you leave everything as it is, then these butterflies, famous all over the world for their beauty, will soon disappear without a trace.
The study involved the Xerces Invertebrate Conservation Society and hundreds of volunteers. They count butterflies in about 300 different locations across the state every year, retaining the information for decades.
Records indicate that the population of monarchs is rapidly declining. So, in 1980 there were about 4.5 million of them, by 2005 there were just over 100, 000, and last year there were only about 28, 500 individuals.
Today scientists are concerned about the question: What is the lower limit of the size of this population, after which its restoration will become impossible? In their opinion, this is 30, 000 individuals. Apparently, the monarchs will finally disappear in the next 2 years.
And yet there is still hope to revive the endangered species of monarch butterflies. Scientists assure that it all depends on what measures humanity is ready to take for this.