29 Tree Swallows at Pointe Mouillee on 12/27

[Karl Overman]

On December 27th, as part of the Rockwood Christmas Count, Lyle  
Hamilton, Sean Bachman, Jim Fowler and I drove around Pointe Mouillee  
in Monroe County.  It was an ice-bound setting and uninteresting  
birding--except for finding 29 Tree Swallows actively feeding over  
frozen marshland just inside the Mouillee Creek entrance.  Today was  
a unique day this late fall/early winter with temperatures around 60  
degrees.

As anyone who lives in the Great Lakes area is aware, this has been a  
cold and early winter with very few days about freezing since around  
November 24th.
If you assume they are not recent arrivals (see below), then they  
must have a survival technique that I can't imagine for an insect  
eating bird.  The birds were easily seen has they flew high in the  
air as well as low over the water covered ice.

In the winter of 2005-2006 Michigan had unprecedented numbers of Tree  
Swallows linger well into January in Monroe County, especially at  
Pointe Mouillee(Last seen that winter on January 27, 2006, 1 bird at  
Pointe Mouillee by Neil Gilbert?)  On December 30, 2005 Adam Byrne  
had 24 Tree Swallows at Pointe Mouillee.  But that was an amazingly  
warm winter unlike this year.

This year Adam Byrne and company surveyed Pointe Mouillee on December  
1st and found one Tree Swallow, and I recall being surprised that  
they found even one given the weather conditions.  A few Tree Swallow  
reports continued this early winter up to December 15th (Tom Pavlik  
4-5 birds at Pointe Mouillee headquarters) but not in the large  
numbers we found.

Alan Wormington reported from Point Pelee, Ontario that on December  
27th Dean Ware at Hillman Marsh north of Pelee, had what could only  
be described as a significant influx of "spring migrant"  
waterfowl--300 Pintails, 2 Shovelers, Gadwall, 2 teal sp. and 2 White- 
fronted Geese.  These birds, per Wormington, had not been in the  
Pelee area for a month and Hillman Marsh has been completely frozen.

Could the bulk of the Tree Swallows today have been instant migrants  
as well?

Cheers,

Karl Overman