 Until 1995 , it was assumed that the corn crake is monogamous , but it <unk> that a male may have a shifting home range , and mate with two or more females , moving on when laying is almost complete . The male 's territory can vary from 3 to 51 ha ( 7 @.@ 4 to 126 @.@ 0 acres ) , but averages 15 @.@ 7 ha ( 39 acres ) . The female has a much smaller range , averaging only 5 @.@ 5 ha ( 14 acres ) . A male will challenge an intruder by calling with his wings <unk> and his head pointing forward . Usually the stranger moves off ; if it stays , the two birds square up with heads and necks raised and the wings touching the ground . They then run around giving the growling call and <unk> at each other . A real fight may ensue , with the birds leaping at each other and pecking , and sometimes kicking . Females play no part in defending the territory . 
