Date: 09/16/2021

Number: 100

We have been seeing sightings of them roosting in our trees for years now and they have been increasing in numbers over the past 6 years. This is the most we've seen this year! I have many more pictures and videos of this event. We stared to notice them Sept 16 and still more arrived today.

[Additional information contributed by observer, added by Journey North, 09/21/21]:

--Roost formed for 4 days starting on Thursday Sept, 16th becoming fewer by Monday Sept 20th.
--Nearby nectar sources: Unknown, the is a large manufacturing build next door to us but large fields a few miles down the road.
--Overnight temperatures where mostly in the mid to upper 60’s. Wind was mostly out of the east north east as we are on the other side of the Detroit river from Canada.
--Tree species roosting on: Mostly Maples and elder trees as well as some trees/ shrub I can’t identify with small round black berries. Shielded heavily from the wind as there was a think line of trees where they where roosting.
--We took lots of pictures in sections of where they where and roomed in and counted the best we could. This was the first year Ive seen so many.

Trenton, MI

Latitude: 42.1 Longitude: -83.2

Observed by: Laura
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