While my informants grew up in Los Angeles, my informant’s family is from Yucatan, Mexico and he frequently goes down to visit his grandparents who live on a ranch.  He heard this information when he was a child visiting his grandparents. His grandfather taught him this:

“A black bird appears, you’re getting bad news or someone is dying.”

My informant says that, according to his grandparents, it happens very often.  The birds are common in the area and will appear by themselves and in flocks.

Many Central and South American countries have high poverty and mortality rates, so bad news and death is very common.  The people expect something bad to happen fairly regularly, so it is not surprising that a fairly common bird is the harbinger of death and destruction.  This also fits in with similar accounts of black birds, such as crows or ravens, being messengers of death in other parts of the world due to such birds being carrion eaters and associated with the dead and dying.  Edgar Allen Poe’s The Raven had a black bird who taunted the narrator with the death of his beloved Lenore.  This belief is seen in many European countries and those colonized by those countries—Mexico for example.