I've run into a lot of friends who did feed birds, but stopped because of the rats. He's careful these days to keep the bird feed and pecans picked up off the ground and to feed his cat inside. Because rats are nocturnal, seeing rats during the day could mean the rat population is out of control in the area or the food sources are getting low or that those rats are the weaker, less popular ones, forced to go out for dinner when the more dominant rats won't bother them. Rats in Austin mostly eat things such as pecans, figs, seeds, and dog food, but rats will eat almost anything that humans eat and then some. They have been known to cut into the bellies of pigs and calves and to dine on the oil-rich toenails of sleeping elephants, crippling them.
Rats also bite people.
In Austin, last year, rats bit at least nine people. According to Seton spokeswoman Stephanie Elsea, nine cases of rat bite were reported at Brackenridge from January to November of 1999. In all cases the men, women, and children who were bitten were treated and released, Elsea said. David Grand, owner of Applied Pest Control in Austin, started trapping varmints as a kid in Long Island. He and his buddies played in the bogs near their neighborhood.