Drought and Migration
In just a few weeks, the entire migration will travel through Texas where drought conditions are severe. We asked Dr. Brower how the drought might affect the butterflies:

"As monarchs migrate through Texas and northern Mexico on their way to the overwintering sites, they spend considerable time building up their fat reserves by drinking the sugar-laden nectar from wildflowers. By the time they reach the Mexico overwintering sites, this sugar is converted to fat and the bodies of the butterflies are practically butterballs. To fuel winter survival and the migration back into the US the following spring, the butterflies gradually draw down these fat reserves. I am extremely concerned that the terrible drought this year in Texas and northern Mexico will have such a negative impact on the wildflowers that the butterflies will have a rough time building up their fat reserves and many more than usual will die of starvation."