According to Cherka, it appears that the migrating birds adapted through natural selection to the climate conditions. He also added that "For many years, different species went out to the spring migration on their way to the nesting sites, so that the chicks will hatch at the exact time when there will be plenty of food for them, allowing growth of the next generation."
According to Cherka, the past few decades saw a 30% decrease in the number of birds all over the world. "There are many reasons for this, but the fast changes in global climate have probably made the timing of the migration less successful. This decrease is a blinking warning light for the future of the rest of the species all over the world."
Common kingfisher. Photograph: Inbar Shlomit-Ruin, KKL-JNF