 Water rails follow definite routes when feeding , frequently returning to good hunting areas . These rails are versatile and opportunist foragers . They will jump to take insects from plants , climb to find berries , or dislodge apples from trees so they can be eaten on the ground . They will kill birds by impaling or drowning them , particularly if the bird 's ability to escape is restricted . They have been recorded as killing a European <unk> and a king quail in an aviary , and small birds trapped in bird ringers ' mist nets . One bird killed a twite caught with it in a Heligoland trap . They are also nest predators , particularly of small birds that nest in reeds such as the great reed warbler . Water rails may defend a winter feeding territory , although this is smaller than when breeding , with individuals perhaps less than 10 m ( 11 yd ) apart ; favoured sites may hold hundreds of birds . Aggressive behaviour outside the breeding season may extend to attacks on other marsh rails such as spotted and Baillon 's crake . 
