Butterfly Count 2024: It Was a Short and Stormy Count

by Anne Ellis, Butterfly Count Coordinator

The butterfly count results are all in. Looking over the results I can see the numbers are discouraging. To be sure, the count results of 2019 were astonishing (6368 butterflies sighted), but ever since then, the numbers have dwindled. Count coordinators and butterfly aficionados have been pondering the reasons.

This was our 28th count and the protocol set down by the North American Butterfly Association (NABA) was followed: we covered the 174 square miles of the count circle (located in northwest Loudoun County), and we held the count on the first Saturday of August  as usual. Team hours in the field may vary and NABA offers a calculation for consistency. But there are many variables from year to year that we cannot control, such as weather, construction and landscape management practices.

Insects are very sensitive to any changes in their environment. Drought was a big factor this year with most of the count circle in a severe drought. Nectar-rich flowers were relatively few, having gone to seed already or dying back earlier than usual. Many host plants, where caterpillars feed, likewise dropped their leaves or died. Some teams reported loss of customary counting sites, mostly due to human construction. Butterfly habitat was also impacted by recent herbicide spraying along roadsides and power line right-of-ways, and mowing. Turf grass is not butterfly friendly. And, finally, sudden severe storms cut the number of hours scouting in the field by one third or more.

To end on a positive note, many teams reported sighting Common Checkered Skippers in higher numbers than usual, and Wild Indigo Duskywings, which were missing from last year’s count. Our data will be submitted to NABA. The 29th annual butterfly count is scheduled for Saturday, August 2, 2025.

View count data for 2014 – 2024.