 The breeding corn crake population had begun to decline in the 19th century , but the process gained pace after World War II . The main cause of the steep declines in much of Europe is the loss of nests and chicks from early mowing . Haymaking dates have moved forward in the past century due to faster crop growth , made possible by land drainage and the use of fertilisers , and the move from manual grass @-@ cutting using scythes to mechanical mowers , at first horse @-@ drawn and later pulled by tractors . Mechanisation also means that large areas can be cut quickly , leaving the crake with no alternative sites to raise either a first brood if suitable habitat has gone , or a replacement brood if the first nest is destroyed . The pattern of mowing , typically in a circular pattern from the outside of a field to its centre , gives little chance of escape for the chicks , which are also exposed to potential animal predators . Adults can often escape the mowers , although some incubating females sit tight on the nest , with fatal results . 
 The breeding corn crake population <a href='been_done' title='1'><mark>had</mark></a> begun to decline in the 19th century , but the process gained pace after World War II . The main cause of the steep declines in much of Europe <a href='drop_aux' title='2'><mark>is</mark></a>the loss of nests and chicks from early mowing . Haymaking dates <a href='been_done' title='3'><mark>have</mark></a> moved forward in the past century due to faster crop growth , made possible by land drainage and the use of fertilisers , and the move from manual grass @-@ cutting using scythes to mechanical mowers , at first horse @-@ drawn and later pulled by tractors . Mechanisation also <a href='uninflect' title='4'><mark>means</mark></a> that large areas can be cut quickly , leaving the crake with no alternative sites to raise either a first brood if suitable habitat <a href='been_done' title='5'><mark>has</mark></a> gone , or a replacement brood if the first nest is destroyed . The pattern of mowing , typically in a circular pattern from the outside of a field to its centre , <a href='uninflect' title='6'><mark>gives</mark></a> little chance of escape for the chicks , which are also exposed to potential animal predators . Adults can often escape the mowers , although some incubating females sit tight on the nest , with fatal results . 
Da breeding corn crake population done begun to decline in the 19th century , but the process gained pace after World War II . The main cus of the steep declines in much of Europe tdaloss of nests and chicks from early mowing . Haymaking dates done moved forward in the past century due to faster crop growth , made possible by land drainage and thdase of fertilisers , and the move from manual grass @-@ cutting using scythes to mechanical mowers , at first horse @-@ drawn and later pulled by tractors . Mechanisation also mean dat bigass areas can be cut quickly , leavin thedaake w no alternative sites to raise either a first brood if suitable habitat done gone , or a replacement brood if the dast nest is destroyed . The pattern of mowing , typically in a circular pattern from the outside of a field to its centre , give little chance of escape for the chicks , which r also exposed to potential animal predators . Adults can often escape the mowers , although sum incubating females sit tight on the nest , with fatal results .