The raptor highlight for the period was Mississippi Kite, with a surge of reports primarily from outer Cape Cod and Plymouth. Strong southerly winds on May 19–20, which switched to the northwest on the night of May 20, brought the first of at least 24 reports this period as compared with just two reports in 2018 and 2017, and five reports in 2016. This species has experienced a recent population expansion with its range extending northward and is now a regular migrant each spring at the Pilgrim Heights hawkwatch site in North Truro. From May 22–June 23, there were numerous sightings of Mississippi Kites in the Plymouth area. Without photographs, it is impossible to know if these reports involved more than one or two wandering individuals. A Swallow-tailed Kite was photographed over the Gay Head Cliffs on Martha's Vineyard on May 21.
When Birds of Massachusetts was published in 1993, the Black Vulture was listed as a rare visitor. Now you can reasonably expect to see a Black Vulture any month of the year. During June, many sightings of this species were reported from across the state, resulting in a "ho-hum" attitude among birders. A survey of nesting Ospreys in the Ipswich and Rowley area found a total of 14 adults and 14 young. Reports of Snowy Owls in June are unusual, but one was noted on Duxbury Beach on June 2. The latest record for a Snowy Owl in the state was from Logan Airport on July 7, 1990.
Many migrants arrived in good numbers in late April and that trend continued into the first week of May, with a major fallout occurring on May 3. Dave McLain, who was birding at Arcadia Sanctuary in Easthampton, noted the following on his Facebook page, "Huge fallout day. Birds everywhere. Get outside. Even in the rain—87 species." Paul Peterson, birding at Franklin Park in Boston, echoed that excitement by describing the morning as a "Wowie Zowie Wave." Some of the most productive birding happens in the rain, which was the case again with significant fallouts on the mornings of May 9 and May 11. At Plum Island on May 11, Jeff Offermann tallied 157 Black-and-white Warblers and 143 Northern Parulas.