Fathers will receive free admission to Tracy Aviary on Father's Day, Sunday, June 21, when accompanied by a child or grandchild.

Special free tours at 1, 2 and 3 p.m. will focus on bird dads and their odd and sometimes human-like behavior.The emu dad, for instance, starts off by building a nest for the new arrivals. After the mother lays 16 to 20 large blue eggs and disappears (often with a new paramour) the father incubates the eggs for 51 to 57 days, then raises the chicks to adulthood.

The great hornbill dad, on the other hand, might be labeled the "barefoot and pregnant" type, or just the "ultimate provider." Around February he encourages the female to enter a nice, warm tree cavity and proceeds to mud her in, leaving only a small opening through which he will feed her and the chicks. The female and chicks will end up spending almost four months mudded up in the tree.