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Graph of monarch sightings reported to Journey North per month (2006-2010)

A month-by-month, year-by-year look at spring migration.
This graph shows how May's record 367 sightings compare to sightings reported each month during the past 5 years. Remember, although the graph might appear to show a healthy recovery this May, it actually only shows that 367 monarch butterflies were sighted. Scientists are careful not to draw conclusions based on limited data such as this example.