Surrounding of the nest

This week, while observing Roderich and Elizaveta, I have been keeping a closer eye on the surroundings.  During my observation,I have noted the two evergreens that are to the right of the nest.  Both have an abundance of branches, which have themselves an abundance of little needles, making them look like a big cotton ball. The one closest to it has the normal green you expect of trees, while the other one has a blue-gray tone imbued in the green which makes it look sharper. 

The two evergreens, top left of building is the nest.

                                                                           

 

Right in front of first evergreen

                                                                                

From my position in front of the trees, the branches hung to about my waist. I ducked under and immediately noticed the warmer feel to the air.  These branches, they made a sort of overhang, seem to be blocking out the elements somewhat.   

View from inside branches, branches blocks out view of outside as well as in it seems

 I saw the advantage of using this as my new observation point and looked up to try and spot the nest.  I was disappointed as I only saw the umbrella-like limbs, but i had grown curious because I started to hear a pair of birds.  I never thought, until that moment, that two or more different species of bird could be so close to each other so carelessly. I saw the advantage those birds had due to the shelter the branches provided, and that caused me to wonder why the pigeons' didn't do the same. The trees limbs were great as they protected against the elements, while the nest they have now, If the weather was in the right direction would harm them.  Maybe the birds don't like sharing the exact nesting areas', so two nests can't be in the same tree? Or, the pigeons just aren't suited to nesting in a tree like an evergreen, or they just don't like something about the tree? As my observations of these birds increase, I seem to be gathering more questions rather then answers, and seem to be getting more confused rather than gaining an understanding of them. Though I am getting rather fond of them, especially when I see them on chilly nights, fluffed up against the cold, and content with each other.