Monarch butterflies should mostly be in Texas by now, winging their way to Mexico for the winter, the AP reports. But Darlene Burgess keeps seeing colorful clusters of them—and she lives in Canada. "As nice as this is to see, I really wish I wouldn't see it because they're running out of time," said Burgess. "It's really not good for them." It's not just Canada. Swarms have been seen elsewhere, including New Jersey, at levels more normal for late September and early October. Scientists say tens of thousands of the butterflies are likely to be stranded far north of where they'd normally be this time of year because of the unusually warm weather and strong winds that have kept them from migrating south, said biologist Elizabeth Howard.
Many of these butterflies might not even be alive if not for the warm weather. They are thought to be a sort of bonus generation—they were able to develop and emerge late in the season because it's been so unusually warm. Monarchs typically arrive in Mexico around Nov. 1. This many "stragglers" in Ontario and elsewhere is "definitely new territory for us," said biology professor Chip Taylor. Some monarchs were born late, some didn't move south because temperatures were warm, and some couldn't move south because winds were coming from the south for weeks. Now they may be stuck because temperatures are starting to fall. Howard said their muscles don't work when temperatures dip into the 50s. And if they don't freeze, they are likely to starve to death because much of the plants they need to feed their long voyage south are already gone for the season.