Since July 27, 2025 I have observed 371 Common Milkweed (Asclepius syriaca) plants, almost entirely around Toronto.
That makes me the #1 observer in Toronto, #4 in Ontario, #7 in Canada, and #17 in the world.
Author: Milan
In the spring of 2005, I graduated from the University of British Columbia with a degree in International Relations and a general focus in the area of environmental politics. Between 2005 and 2007 I completed an M.Phil in IR at Wadham College, Oxford. I worked for five years for the Canadian federal government, including completing the Accelerated Economist Training Program, and then completed a PhD in Political Science at the University of Toronto in 2023.
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Additional common milkweed would help Canada meet its share of the trinational eastern migratory monarch butterfly recovery target
https://www.facetsjournal.com/doi/10.1139/facets-2024-0063
The eastern migratory monarch butterfly (Danaus plexippus) population has declined by ∼84% between 1993 and 2024. Population recovery in the Midwestern United States is limited by the availability of the monarch’s main host plant for egg laying—common milkweed (Asclepias syriaca). The extent to which common milkweed availability is limiting in other breeding regions is unknown. Our objective was to determine whether Canada has enough common milkweed to support its share of the trinational eastern migratory monarch population recovery target, given ∼29 stems of common milkweed are needed to contribute one adult monarch into the fall migratory population. To meet this objective, we estimated the number of common milkweed stems in Canada using published common milkweed availability estimates by land cover type. We also estimated the size of the Canadian monarch population if the recovery target was achieved using published estimates of wintering monarch density in Mexico, fall migration survival rates, and the relative proportion of monarchs entering fall migration from Canada. We estimate that Canada currently has 484 million common milkweed stems (range: 111 million–1 billion stems) and increasing this amount by 1.61 times (i.e., by ∼295 million stems), or equivalently, by 61%, would support the recovery target.
All-time, you’re 634/6,008 = 10.55% of every CMW observation ever logged in this box, and you’re the single largest contributor outright (next is data_nerd at 310).
But the dataset runs back to 1978, and your account only starts 2025-07-29. Restricting the “all” pool to your active window (2025-07-29 to 2026-07-31) — 1,695 records — your share jumps to 37.4%.
Restricting further to place_guess containing “Toronto”: you’re 22.8% of the all-time Toronto-labeled total, but 64.5% of Toronto-labeled CMW records logged since you started. Two out of three Toronto milkweed observations in the last year are yours.
You’ve hit 159 distinct ~1km grid cells; the rest of the community collectively covers 1,592. Of your 159, 55 (34.6%) have zero other observer — a third of your footprint is ground nobody else has logged CMW on.
In the 104 cells where you do overlap other observers, your median share of that cell’s total observations is 50%.
189 of your 253 distinct place_guess strings don’t appear anywhere else in the dataset.