 The corn crake is solitary on the wintering grounds , where each bird occupies 4 @.@ 2 – 4 @.@ 9 ha ( 10 – 12 acres ) at one time , although the total area used may be double that , since an individual may move locally due to flooding , plant growth , or grass cutting . Flocks of up to 40 birds may form on migration , sometimes associating with common quails . Migration takes place at night , and flocks resting during the day may aggregate to hundreds of birds at favoured sites . The ability to migrate is innate , not learned from adults . Chicks raised from birds kept in captivity for ten generations were able to migrate to Africa and return with similar success to wild @-@ bred young . 
 The corn crake <a href='drop_aux' title='1'><mark>is</mark></a>solitary on the wintering grounds , where each bird <a href='uninflect' title='2'><mark>occupies</mark></a> 4 @.@ 2 – 4 @.@ 9 ha ( 10 – 12 acres ) at one time , although the total area used may be double that , since an individual may move locally due to flooding , plant growth , or grass cutting . Flocks of up to 40 birds may form on migration , sometimes associating with common quails . Migration <a href='uninflect' title='3'><mark>takes</mark></a> place at night , and flocks resting during the day may aggregate to hundreds of birds at favoured sites . The ability to migrate <a href='drop_aux' title='4'><mark>is</mark></a>innate , not learned from <a href='negative_concord' title='5'><mark>adults</mark></a> . Chicks raised from birds kept in captivity for ten generations <a href='uninflect' title='6'><mark>were</mark></a> able to migrate to Africa and return with similar success to wild @-@ bred young . 
Da corn crake solitary on tdawintering grounds , where each bird occupy 4 @.@ 2 – 4 @.@ 9 ha ( 10 – 12 acres ) at one time , although the total area used may b double that , since an individual may move locally due to flooding , plant growth , or grass cutting . Flocks of up to 40 birds may form on migration , sometimes associating w common quails . Migration take place at nite , and flocks resting durin the day may aggregate to hundreds of birds at favoured sites . The ability to migrate innate , not learned from no adults . Chicks raised from birds kept in captivity for ten generations was able to migrate to Africa and return witwidmilar success to wild @-@ bred young .