Cliff Swallow is a wonderful creature.
The swallows build their homes out of mud and spit.
The mud balls are the size of a pea,
and the houses are about the size of a grapefruit.

Twit!

The birds almost always nest over water,
or close to it.
The insects they rely on are
much more readily available in aquatic habitats,
with mayflies, caddis flies, damselflies, moths,
love bugs, and other swarming insects
all featured prominently on the menu.

Let's dive
and party!

So the cliff nearby the river, stream
was the habitat of the swallows,
for a long time.

  We kinda   
   liked it here   

But almost the entire population of cliff swallows
in much of the United States has evolved
into something that might more aptly be called
'bridge swallows.'

Let's 
    jet out here!  

Why? The living is easier under a bridge
than it is stuck to a vertical wall of rock.

Advantage: The nests are protected from rain
and weather much better than
a nest on a cliff face ever could be.

   My old place?     
It was a total   
leaky mess...  
     Nah, it didn't even        
have a roof!     

             

Nobody exactly know since when
they migrated from cliff to bridges
but some states like Alabama,
we can often see the swallows
living under the bridges
- so their official habitat is ‘bridges’

♭ under the bridge
under the bridge ♭
♯ Darlin, it's better
          Life is endless spree          

Wait, under the bridge?
Then they must have seen
the Boston Tea Party?
in 1773?

ok, this is
interesting

Wait, did they stay with
Robert Kincaid and Francesca Johnson
at the Madison-County Bridge?

Ah - I have
a lot to say 

Wait, they may have seen
the Martin Luther King
march in Selma in 1965!

Swallows have watched
a lot of histories,
just living
underneath the bridge!