Dec 19th, 2019 : Anti-Santa Shield
 

Dismantling this chimney revealed 25 generations of bird nests, no access for Santa for at least that long.
Don't know why they were taking it apart but the house in the background is typical of the big old houses
with lots of fireplaces traditional or Franklin throughout the house for heat.
With central heat conversions many chimneys went unused.

http://cellar.org/img/nests.jpg

Someone suggested it might be the work of Vaux swifts which are tiny little birds at only 4.5 inches long
and weigh less than an ounce. The feather on top of the nests is way to big for that bird but may have been
found nest lining material.

link

I'm willing to place a small wager on that being the work of Jackdaws.
They're a common European member of the crow family and notorious for building nests in chimneys.

Here's the suspected perp:

Attachment 69349

And the view from the other end of the chimney.:

Attachment 69350

Link

Link

That will teach you to not have a cap on your chimney.

I wonder if it's code for new homes today. It should be.