504 CHAINS OF CIRCUMSTANCE 



more and more frequent until they unite in the solid mass of 

 the gullery itself (Fig. 89, p. 503). *. 



The changes of vegetation which took place in the main 

 and subsidiary gulleries seem to have been due partly to 

 the fertilizing of the soil by the food refuse and excreta of 

 the enormous numbers of birds, partly to the puddling of the 

 surface by their feet and to the surface accumulation of their 

 nests, so that superficial water was retained, and the peat 

 bed with concealed and deep moisture was transformed into 

 a surface marsh. 



Such changes did not come alone. No observations 

 were made upon the minute insects and lesser creatures of 

 the moor, although the development of a surface marsh must 

 have closely affected their welfare, their numbers and even 

 their kind. From his practical point of view, however, the 

 keeper noticed that the Grouse ceased to nest and dis- 

 appeared, and that in their place, attracted by the marsh 

 and the cover of the rushes, there came to feed and nest 

 first a few, then many Teal Ducks. A single flock of these 

 containing as many as seventy birds was seen when the 

 gullery was at its height. 



Now after the Gulls had been protected for some fif- 

 teen years, they were ousted from the White Moss. /The 

 villagers, incensed at the destruction of their hay crop, which 

 had been replaced by docks, made persistent raids on the 

 gullery, and the proprietor, regretful at the disappearance" of 

 Grouse, ceased to protect the Gulls for his Pheasants. In the 

 early summer of 1917, scarcely a Gull was to be seen, and 

 not more than thirty pairs nested, where a few years before, 

 there were some 2000 pairs. As a result of the disappear- 

 ance of the Gulls a gradual reversion towards the old state 

 has been in progress. The docks have almost disappeared, 

 and the rushes are giving way to rough grass and even 

 to heather. The Teal have gone, in 1917 only one pair 

 nested, and the Grouse are returning, so that on a moor 

 where only three brace of Grouse were shot in the heyday 

 of the gullery, now some twenty brace fall to the sportsman's 

 gun. 



In the case of the Gulls and the Moorland, an insignifi- 

 cant influence the protection at first of a few Gulls set in 

 motion an endless chain of circumstance, of which we have 



