2,    adults,    anatids,    animals,    atratus,    aves,    birds,    common,    copulates,    copulating,    copulation,    duckmeat,    format,    lakes,    laterally,    move,    movement,    moves,    outdoors,    outside,    pair,    river,    Sex,    summerly,    summertime,    summery,    sunny,    sunshine,    swans,    swimming,    swims,    waterbirds,    waterfowls,