Roosting Monarchs
Monarch butterflies only migrate during the day. At night they cluster together in overnight roosts. Some roosts last for only one night. Others last for two weeks or more. A roost may have a handful of butterflies or far too many to count.

"We had 200 to 300 monarchs in the large trees in our schoolyard. We're only a block from Lake Ontario so it was a good place to rest before heading onward!" wrote students from Ontario.

Photo: Emily McCormick