It's not uncommon for a species to have a strong year sometimes. Here also birds and parasites find their host and reduce the population again. In the following year the parasite hardly finds a host and this population of parasites collapses. Now the butterfly (egg and caterpillar) can recover and the population rises again. This is how nature has worked for thousands of years. We humans intervene more and more often in this cycle and destroy habitats. The agricultural industry creates gigantic monocultures with all their disadvantages for flora and fauna. In many areas the biodiversity in the cities is higher than in the countryside. Habitat destruction, eutrophication and pesticides are the insects' greatest enemies.

Greetings from Germany 🦋