Gull-like bird with long narrow tail and W shaped wings (1 Viewer)

I know this is a longshot since I did not have a camera but here goes ...

We saw 2 identical birds soaring and chasing each other just above the tree line.

If I was in the Galapagos, I would have sworn they were miniature frigate birds judging by the shape of the wings and long thin tail. But they were too small for a frigate bird (and wrong continent in any event).

These were at least the size of a large gull, or maybe bigger than a large gull. Mostly white but maybe had some grey (not sure about that). The wings were unusual in that they had a very pronounced W shape and they were narrow (or frigate bird! yeah, I know its not, but its the closest I could come to describing the overall shape). The tail was also unusual - long and thin like a frigate bird when soaring. They were not Copper Hawks - tail was more narrow than a coopers, and wings were not the right shape for any hawk I have seen (plus, mostly white and no bars on tail).

Wingspan it was somewhere between 16" and 24" but hard to say exactly due to the fact that they were flying in and out a lot.

I am going to sit out and see if I see them again with my camera..In they meantime, any ideas what they could be?

Location: Northfield, IL
Date: June 24, 2020
Time: about 6pm

Could it be one of our Kites?

Hi there and a warm welcome to you from those of us on staff here at BirdForum :t:

Pleas join in wherever you like.

KC Foggin said:

Could it be one of our Kites?

Hi there and a warm welcome to you from those of us on staff here at BirdForum :t:

Pleas join in wherever you like.

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I thought Kite also, but I did not think any kites migrate as far north as Chicago?! We do get a lot of interesting migratory but not sure a kite would migrate this way, would it?

According to eBird, Mississippi Kites have been reported around or north of the latitude of Chicago in Iowa, Wisconsin, Michigan, and southwestern Ontario this year in either May or June. None have been reported from the Chicago area however.

Microtus said:

According to eBird, Mississippi Kites have been reported around or north of the latitude of Chicago in Iowa, Wisconsin, Michigan, and southwestern Ontario this year in either May or June. None have been reported from the Chicago area however.

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That's not long-tailed, though - it'd need to be Swallow-tailed Kite :t:

Nutcracker said:

That's not long-tailed, though - it'd need to be Swallow-tailed Kite :t:

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Yes, and I think Kites are too big, and not sure they have that notched W shaped wing that was really the most striking feature of the bird we saw.

I have been looking through my Field Guide and think it had to be a Tern of some kind .. I did not see any other bird family in the FG matches the sharp W shaped wing, thin tail, size and color.