4 days of observations - Serena and Sam

First of all, a warning.  If you do not have a huge interest in blue herons, it's probably best to skip this post.  I feel some sort of compulsion to record the actions of two herons, named Serena and Sam, whose nesting and mating efforts appear doomed to failure.  They began one nest, which either fell apart, or blew away, as noted in my post of April 13th.  I went back on Monday, April 20th, and they have begun building again.  Many of these pictures were taken with poor light.  I used photoshop to lighten them to the point where I had a somewhat better chance of figuring out what was happening.  Here is an account of the last four days of their actions.  

MONDAY: APRIL 20

Only one picture.  I waited around for a long time, but saw only Serena.  Sam did not make an appearance.  She worked diligently on the nest, and it appeared to have progressed a bit further than the original one.

TUESDAY: APRIL 21

I was there between 4:00 and 6:00 p.m.  Serena was there, working on the nest when I arrived.  Sam flew in shortly after.
The picture quality is too poor to be sure, but I think they may be mating here.
Sam then appears to be going to fly away.
However, he settles a short distance away, and attempts to break off some branch pieces.
He passes them to Serena.
I am wondering if they are engaging here in a mating display called bill clacking. 

There is a beautifully written article by Tom Horton that describes some blue heron mating behaviors.  It is definitely worth reading, both for the information and for the obvious love that he has for these birds.  One paragraph in particular really touched my heart.  I will copy that here:

 At times I have observed heron couples in the throes of springtime amore, touching gently, almost sensuously- thigh to thigh, breast to breast, bills tip to tip; and in this posture it happens that their glossy necks, curving fluidly between chest and beak, form something akin to the shape of a valentine. Watching them gazing steadfastly into one another's lidless, unblinking eyes, it is not hard to recall old Calvert Posey's moniker, "lovebirds," and to believe that something more than just instinct is at work.

After the bill episode, Sam flew over Serena.

There was another episode of what may have been mating, and then they settled very close to each other, and appeared to be working on the nest.  I have since read another article about Little blue Herons by James A. Rogers, with some VERY detailed, scientific data.  I have not read all of this, and it is about a different type of heron, but I suspect its description of twig grasping as part of the mating display could apply to both little and blue herons.  
Here, Tom Horton's words in the quoted paragraph about "lovebirds" seem appropriate.
I watched Sam and Serena for a long time.  Finally, Sam flew off.
Was he going to get more branches?
He seemed to struggle a bit here.
Then, he was gone.

WEDNESDAY, April 22nd, around 6:30 p.m.

I watched Serena for well over an hour.  Other herons were bringing in branches to their mates, some returning every ten minutes.  Sam did not make an appearance in the time that I was there.  Serena seemed to be looking for him, but also worked hard on the nest.  I thought it progressed a little bit.

THURDAY: April 23rd, around 6:30 p.m.

Much the same story as yesterday.  I watched for more than an hour.  Serena remained alone, working on the nest.  There seem to be more twigs, but it appears to me to be very poorly constructed.  A mess, actually.
One heron flew in. She ignored him.  Was it Sam?
That heron stared for quite some time at Serena's nest.  I wanted it to be Sam, but if he was, why did he not go closer?  He didn't pay attention to any other nest.  Could he have been another suitor?  No answers to my questions.
He continues to stare.  She goes on with her still terribly inefficient (my impression) nest building.
The heron flew off and Serena remained alone.  I do think her second nest is a bit more sturdy than the first one.  We have had strong winds over the past few days, and at least it hasn't disintegrated.
That's the update on Serena and Sam for now.  

*For anyone interested, I don't have much of an update on Stella and Stanley, because I haven't been going to the heronry in the mornings, when their nest is easiest to photograph.  However, I have seen them working together, and their nest looks very sturdy.  I have a feeling Stella may be sitting on some eggs.