Mallards, the most common, easily observed and ever present birds on Goodacre Lake, put on a free show every day for Park visitors who pause to watch. Mallards are unique and interesting, but are often taken for granted.

Not all Mallards quack! Only females make that quintessential duck sound. Male and female Mallards make completely different sounds. Males make two calls, a whistle- call "piu" and a nasal "quehp".

Male Mallard's feathers are at their most colourful and bright in September because the most active Mallard courtship starts in the fall and continues until spring. This is extremely unusual in the bird world: most birds grow their brightest feathers and look their best in the spring to attract mates at nesting time.

Many people assume that male Mallards leave the Park every year during July and August because the characteristic bright green heads are completely absent. The truth is, males stay right here in the Park, but their feathers are identical to females during the summer. This is called "eclipse plumage," a partial replacement of feathers involving the body and head but not the wings and tail. By September, another complete molt produces bright male plumage again.

Beginning in September and continuing through the winter, Mallards perform eight different visual displays and six auditory displays in their efforts to attract mates. Courtship displays are subtle and last only a few seconds but if you stand at the edge of Goodacre Lake for a few minutes, you are likely to be rewarded by seeing them.

Two of the most common displays are the "head shake" and the "tail shake." Another display called "nod-swimming" involves a duck swimming rapidly with neck fully outstretched, head held just above the water. "Pumping" is a courtship display in which two ducks face one another and begin rhythmically bobbing their heads up and down. For drawings of these and other displays as well as excellent descriptions of Mallard behaviours, see the Stokes Guide to Bird Behavior, Volume One, by Donald Stokes, pp. 31-44, available at the library and in paperback.

The total number of Mallards in Beacon Hill Park has remained remarkably stable over the decades without interference from Park staff. (The persistent rumour that the staff captures and culls Mallards at Goodacre Lake is not true.) Each female Mallard lays from eight to thirteen eggs, so overpopulation would be a problem without the predation of Cooper's Hawks, crows, gulls, herons and raccoons. Humans lament any loss of cute fluffy ducklings but happily, mother ducks can't count.