1 6 Coward, Faunal Survey of Rostherne Mere. 



small parties of Swans fly from mere to mere, and on so 

 large a water the resident birds are often unable to drive 

 away visitors from other places. In most years only a 

 single pair nest, but no sooner can the young fly than two 

 or more families may often be seen on the water. The 

 economic value of the Swan on a small water as a useful 

 factor in keeping in check the rapid growth of the 

 American weed, Elodea, is now generally recognised, but 

 although this troublesome weed does occur, the area of 

 deep water is too considerable to be choked by its spread. 

 The Swan is blamed for annoying breeding ducks and 

 other waterfowl and killing the young, but at Rostherne, 

 again, the number of nesting birds is so much larger than 

 of Swans, that little serious damage is done. 



It is likely that occa- 

 Branta leucopsis (Bechstein). sionally wild geese visit 



Rostherne, but we lack 

 satisfactory evidence of the fact. Grey geese do pass over 

 the county on migration, and we have had reports of birds 

 at Rostherne which sounded like both Barnacle and Brent. 

 On February 8th, 191 2, or possibly a day or two earlier, 

 Mr. G, E. Robinson, one of the gamekeepers, saw a very 

 wild bird flying about the mere ; he described it to us as 

 like a Canada, only smaller. That this bird was probably 

 a Barnacle is suggested by the fact that on January i8th, 

 191 2, the day following a notable gale which brought 

 many birds inland, one was seen by Mr. M. V. Wenner 

 on Radnor Mere, Alderley.^ Other birds which were 

 driven inland by the same gale remained in the neigh- 

 bourhood for some time, and it is possible that the bird 

 which was seen at Radnor wandered from mere to mere, 

 or that others of the same species were moving about 

 Cheshire. 



^ British Birds. V., 279. 



