Did you see a Monarch Butterfly today? Well wish it well for the great migration to Mexico because that’s where it’s headed! Today marks the start of the peak migration for our latitude (39).
Monarch Watch put together this great table that shows how the migration plays out.
| Latitude | Midpoint | Peak in monarch abundance |
| 49 | 26 August | 18-30 August |
| 47 | 1 September | 24 August -5 September |
| 45 | 6 September | 29 August – 10 September |
| 43 | 11 September | 3 – 15 September |
| 41 | 16 September | 8 – 20 September |
| 39 | 22 September | 14-26 September |
| 37 | 27 September | 19 September – 1 October |
| 35 | 2 October | 24 September – 6 October |
| 33 | 7 October | 29 September – 11 October |
| 31 | 12 October | 4-16 October |
| 29 | 18 October | 10-22 October |
| 27 | 23 October | 15-27 October |
| 25 | 28 October | 20 October – 1 November |
| 23 | 4 November | 27 October -8 November |
| 21 | 11 November | 3-15 November |
| 19.4* | 18 November | 10-22 November |
Monarchs are triggered to migrate by the shorter days and cooler temperatures and in fact, the butterflies that emerge in this late summer/early fall period do not develop sexually. Instead they go into a state of diapause (like a long term adolescence) and just focus on nectaring and flying south to Mexico.
Once they arrive in Mexico (around the last week of October) they’ll rest for the winter and then by next February, they’ll become sexually mature, mate and start the journey north, laying eggs in the spring.
If you see a Monarch over the next few weeks, take a minute to watch and enjoy, and when it takes off whisper a wish for safe travels!