Yes there are, but by these days arrival is just beggining and the nuclea of butterflies in between the trees are yet very unstable. That´s the reason why biologists in charge of the sanctuaries, in coordination with the owners of the woods, authorize tourists visits from November 15th to 20th on, depending on the year.
Normally sanctuaries of butterflies are open to the public from Nov. 20th on. Reason is because colonies of butterflies are not stable yet, they could be spread out through the woods before this week, and authorities try to avoid crowds that could interrupt their natural process of selection of the right place to hybernate. As they behave, and under supervision, a few people couldn´t damage them.  But in order to avoid suspiciousness, authorities open until such dates.

Earliest we have gone is November 4th of 2006, and found several trees already covered with the butterflies. Nevertheless, by this days they are very dynamical yet, and they move constantly erasing rapidly the nucleus or so called colonies. But speaking of Nature, nothing gives you the warranty that it should be like this again next year. If it is cloudy we see nothing. From Patzcuaro to Morelia it is an average of one hour. We reccomend at least to stay in Morelia the previous night to your tour.