I was confused as to your comment as well. As you've discovered, those birds you've seen congregating and socializing loudly are
great-tailed grackles or common grackles and not the State Bird of Texas, the
Northern mockingbird. Grackles roost in large groups, whereas mockingbirds are primarily solitary. Mockingbirds are named for their ability to mimic MANY other sounds, including other songbird's songs, as well as more peculiar sounds, such as a rusty metal gate or even a dog barking.
Many people dislike grackles due to their raucous calls and their habit of flocking in large masses. However, it takes all kinds to make nature what it is. I think grackles are beautiful in their own way... look at one of the males shining in the sunlight sometime -- purple and blue-hued against deep black feathers and elegant long black tails (if they're a great-tailed grackle and it's not summer, when they shed their long tail in 'preference' of a lighter "wardrobe") Also, grackles do sing, though I guess to most folks it may not sound like typical bird song. I equate the grackle's song to what a robotic bird might sound like -- there's an eerie "electronic" quality about their voices. Even the
female grackles are pretty, in their own way -- chocolate-colored breasts set against black.
Looks like I need to add more birds to the Wild Texas
Wild Guides!
Regarding the "disappearing mockingbirds": I, too, have seen fewer Northern mockingbirds in my northeast San Antonio suburban backyard this year. I normally have one or two that stake out my suet feeders as their territory. I've heard one singing, but he hasn't opted to guard my feeders. I simply thought that due to the atypically wet year we have had, there are more than enough bugs for the mockingbirds, so they have little reason to fret over guarding a suet feeder.
If you're curious about my backyard setup, I have a small backyard but it's got good cover (two oleander bushes, an oak alongside my house, and 6 or 7 young green cloud Texas sage bushes against the back fenceline, though the sages are still less than 4" tall). I have 3 or 4 seed feeders filled with black-oil sunflower seed, as well as a birdbath equipped with a dripper, to keep it filled & attract birds. In the summer months, one of my seed feeders is replaced with a stocked hummingbird feeder. I have two suet cake cages, but don't tend to fill them in the heat of the summer since the suet quickly MELTS!