Date: 03/23/2009

Number: 1

Yesterday (March 23) many Monarchs were flying north through Contepec. I saw many on the road to Maravatio and even some in the center of that town. Today many are flying back with some stopping to drink in the mud by our pond. The days before yesterday, Sunday (March 24) and some days before that, were windy and colder so maybe that is why this group started migrating yesterday. It is of concern that many fly so low when crossing roads and highways. I think that many probably get killed crossing the freeway that goes past Maravatio toward Guadalajara. Also I have seen many going paralell to and over the very busy truck route from Querataro to San Luis Potosi.

The wintering site in Contepec was small. Probably not more than 12 or so small trees. The Monarchs have now all left our mountain (Altamirano). On the 25th of February I saw the first returning butterflies (i.e. migrating north, from the sancturies south of Contepec). On a bike ride around the northern part of our mountain in the late afternoon I saw many settling in oak trees for the night. Several pairs of butterflies were flitting about together and others were lighting on the white flowers of "Boshe" a shrub of the Compositae. That is the earliest that I have seen them leaving. Yet, two weeks later (~ March 11), woodcutters reported that there were still a smaller number of butterflies on the mountain. I have not had the time to go to the sanctuary recently.

Reported by Mr. Neal C. and forwarded to Journey North by Dr. Lincoln Brower who added, "It is very interesting to know that the monarchs stayed the winter on Altamirano, and to have information on the timing of their leaving." Regarding the 25th of February departure date, "While we do not have extensive data, I believe that the early reports of monarchs leaving their overwintering colonies are indicative of three possible anomalous conditions.....(1) global warming, (2) premature desiccation (drying out) due to warm and dry weather (likely associated with 1), and (3) excessive exposure of the overwintering colonies to the elements due to logging. The lack of consistent monitoring of departure dates from the colonies in Mexico is one of the major holes in our long-term records."

Contapec, MIC

Latitude: 20 Longitude: -100.2

Observed by:
Contact Observer

The observer's e-mail address will not be disclosed.
Contact will be made through a web-based form.