A few months later, people from all over North America and Mexico began returning his labelled butterflies to him. Mexico was the southernmost area from which he had received a butterfly, so he started traveling there to look for the Monarchs. For many years, he traveled to Mexico. There he climbed through jungles, walked through forests, and talked to the people he found. He finally heard there was a place west of Mexico City where people had seen lots of monarchs all together. After a long search, He finally found millions of monarch butterflies covering every part of the area.