In case you don't get the NY Times Canada newsletter ;) an article about the eBird post earlier this week, which adds some detail and context:
https://www.nytimes.com/2018/05/31/science/warblers-canada-migration.html?em_pos=small&emc=edit_cnda_20180602&nl=canada-today&nl_art=1&nlid=72344510c%3Dedit_cnda_20180602&ref=headline&te=1

Teresa Michelsen
Port Townsend, WA
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