THE BITTERN 55 



purposes areas they may visit on autumn migra- 

 tion. Normal dispersal is the result of range 

 expansion in spring for purposes of reproduction. 

 That being so, we hope the reader will understand 

 that the Bitterns still visiting us are not seeking 

 in any way to extend their breeding area ; that 

 they are descendants of those individuals which 

 increased the range of the species across our islands 

 or from a British base, probably when the North 

 Sea was an extensive marshy plain, and are in the 

 habit of returning here to winter or to pass over 

 our area to more southern districts. Introduction by 

 man might succeed in reinstating the Bittern as a 

 British bird, as it did the Capercaillie ; but we need 

 not foster any hopes that the species will ever 

 settle here without such aid, however carefully we 

 may preserve these visitors, or whatever induce- 

 ments we may oiFer them to do so. Be all this as 

 it may, the Bittern should not be shot at all in this 

 country, or the few that still continue to visit us 

 in winter or on passage may ultimately be ex- 

 terminated, and the bird cease to be a " British " 

 one in any sense of the term. The Bittern, from 

 all accounts, was pretty generally and commonly 

 distributed over the British Islands " in the days 

 of long ago," — that is to say, in suitable localities. 



