Try to say that fast three times. : ) It’s February. And….so what? Well, that’s when the Western Bluebirds 
return. That’s if they’ve been gone of course.
Some stay put. Even in cold climates. But especially in a place like southern California. So we get to see and hear them year round. And they get a nice jump on things. They are already getting ready to nest here. . A month earlier than many other places.
But many more migrate. Even to San Diego. In flocks so high so you may not see them. But you can hear them. They don’t sing…exactly. Instead they give a series of calls that’s a stand-in for song. Still it’s pleasing. For several reasons. Not the least of which is the translation : “It’s spring, it’s spring, it’s spring.”
Harbingers of spring. You can count on. They’re even more reliable than snowbirds.
And they need to get busy. The survival rate is low. They may need several clutches in a single season just to keep up. Like many birds they’ve lost habitat. They are cavity nesters. And there simply aren’t as many forest trees as there used to be. So fewer woodpecker holes. So more competition for nesting-sites from imports like House Sparrows and European Starlings. (Stupid Starlings.)
So a low inventory of woodpecker holes combined with more competition makes it a sellers’ market. Squabbles are common. Birds get killed.
Western Bluebirds have a long list of enemies anyway: tree swallows, House Wrens, squirrels, mice, cats, raccoons, possums, snakes, woodpeckers, Scrub Jays, Cowbirds, Crows and Ravens, flickers, grackles, owls, Cooper's hawks, ants, bees, wasps and earwigs. Yes earwigs. And we think we have it tough.
But if you love Western Bluebirds, and who doesn’t (I don’t mean like those on the list), you’ll be happy to know they’re doing ok in spite of all that. Their secret?
People have put out thousands of bird houses. At least it gives them a fighting chance. They are specially designed to discourage competition and predation. Interested? Bluebirds are after all the number one pest remover in yards.
Anyway. So I was happy to hear a friend—well her husband actually--put one out this year. He took down their old nest. Bluebirds had been living on the back porch. Beautiful. Musical. Delightful. Messy. She’s concerned they won’t come back because they won’t want to move. After all it’s not like you can give first time homeowner incentives.
Or can you?
They can be coaxed with a favorite food--and nothing says lovin’ like live mealworms. To a Bluebird anyhow.
Besides Bluebirds actually love bird houses. They make perfect nest sites. And females love them. 
I say that because for one thing everyone knows wives choose the new house. Second female bluebirds build the nests. Exclusively. Now if you’ve ever observed Bluebirds building their nest you might say, “Wait a second….I’ve seen males carrying sticks back and forth.” Yes. Well it’s the “and forth” part that’s at issue. They’re posers. It’s all show.
A male will carry a stick to the nest. Enter. Poke his head out. Wave the stick around. Come back out. Show off his wings. Then fly away with the stick. Sometimes two. Now that’s just not being very helpful.*
Female Western Bluebird
I don’t mean to sound tooo critical. After all, truth be told, I’ve pulled that maneuver myself a few times. I’ve found if I can manage to make a bigger mess by helping than not? I get kicked out of the kitchen. Then I have to go watch the game.
So he goes and guards the perimeter while she finishes the work.
To his credit,though, he does help bring home the bacon. Or grasshoppers as it were. Both feed the young birds. Then the male takes over for a couple weeks after they are fledged and feeds them while the female goes and builds the next nest.
So see? They have it all arranged.
Distinguishing Marks: the head is all blue; back, breast and sides are red-brown; and on the belly the sport classic whitish; Females are a grayer version. But the best way to tell is if they are in the west. (Inane but reliable.)
Boring Fact: youthful birds or adult males often help raise baby birds from a family member's clutch.
* Really Fine Print: for the sake of transparency, I pushed the boundaries of known behavior. A little. I don’t mean I discovered anything. I inferred a few things. Male nesting displays are well documented for Eastern Bluebirds. Not so much for western. However, there are ornithological observations suggesting they too may display. So there. : )