In New York, Monarch butterflies begin their annual fall migration in mid-August. These butterflies are the great-great-grandchildren of the monarchs that migrated to Mexico last fall.
Here are some ways you can help monarchs:
• Turn a portion of your lawn into a wildflower meadow to provide food (nectar)—plant milkweed or other native wildflowers.
• Delay mowing areas with milkweed until later in the fall.
• Avoid using pesticides—they kill all life-stages of monarchs (egg, caterpillar, chrysalis, and adult).
• Report sightings of adults or caterpillars online. View a map of the sightings so far this year—caterpillars have already been spotted across the northeast
Not sure when their migration peaks in your area? Check out this chart.
Latitude Midpoint Peak in monarch abundance
49 26 Aug. 18-30 Aug.
47 1 Sept. 24 Aug. - 5 Sept.
45 6 Sept. 29 Aug. - 10 Sept.
43 11 Sept. 3 - 15 Sept.
41 16 Sept. 8 - 20 Sept.
39 22 Sept. 14-26 Sept.
37 27 Sept. 19 Sept. - 1 Oct.
35 2 Oct. 24 Sept. - 6 Oct.
33 7 Oct. 29 Sept. - 11 Oct.
31 12 Oct. 4-16 Oct.
29 18 Oct. 10-22 Oct.
27 23 Oct. 15-27 Oct.
25 28 Oct. 20 Oct. - 1 Nov.
23 4 Nov. 27 Oct. - 8 Nov.
21 11 Nov. 3-15 Nov.
19.4* 18 Nov. 10-22 Nov.
*This latitude represents the general vicinity of the overwintering colonies. The monarch colony at El Rosario is usually opened to the public around Nov. 18.
Chrysalis Stage
Have you seen a small, green pod about an inch long? This is a monarch caterpillar (larva) after it enters the pupa stage and is now in a chrysalis. If you see one, try not to disturb it. They will find a safe place, often under a milkweed leaf to enter this stage in their development, which lasts 9-14 days. Sometimes they will pupate hanging under eaves, decks, other garden plants, or even on window screens.
Monarch Tagging
The Monarch Watch Tagging Program is a large-scale community science project that was initiated in 1992 to help understand the dynamics of the monarch’s spectacular fall migration through mark and recapture. For more information go to monarchwatch.org/tagging
