Consider this excerpt from B.C. Robison’s “Birds of Houston”: “Common grackles assemble in flocks in open areas such ... is anything but!), the boat-tailed grackle and the great-tailed ...

Their heads are flat, not rounded like boat-tailed grackles. These birds are common ... grown in on other areas of the wing and body. The tail feathers are frayed, but after the new feathers ...