Butterfly sighting brings thoughts of extinction (Upper West Side, Manhattan)

It's rare to see butterflies in Manhattan, and rarer still to have one land on you as this one did on my cousin as we were walking down a block in the 90s. It was a delightful moment and yet the delight passed quickly as I immediately thought of all the awful things that could explain the butterfly's seemingly aberrant behavior. Was it sick? Had it been weakened from some environmental disaster? Was it a sign of the of the decline in the population of monarchs and the problems with their winter migration? It's hard to know what's going on, at least from a cursory Google search. A column in the Portland Tribune announces ominously that "researchers warn that if present trends continue, Western Monarchs face a 72 percent likelihood of going extinct within 20 years" while an article in the Burlington Free-Press says the monarch migration this year is expected to be "enormous." Of course, both could be true: despite a rise in this year's migration, the lovely monarch might still be headed for extinction.