GOLDEN BE AVER 217 



place. The interstices of the dam were filled in with small peeled willow 

 twigs, grass pulled up by the roots, roots of other vegetation, and rocks 

 up to 6 inches (150 mm.) in diameter. Some of these rounded rocks had 

 been placed on the rim of the dam, on top of everything else, as if to 

 weight down the mass. The whole structure was notably level-topped and 

 symmetrical in curvature. Although newly made and relatively small, it 

 already served to raise the water level in the slough. 



The second dam, a much larger affair, was built across the mouth of 

 a slough where it emptied into the main Merced. This dam was built 

 by the beavers on a foundation of large rocks which some boys had placed 

 to deepen the water in a swimming hole above ; but the curvature (or rather 

 the two arcs of the curvature) did not, evidently, relate in any way to 

 the foundation which had been put down by the boys. One end of this 

 dam had been carried away by flood water in the slough. It had been about 

 40 feet (12 meters) long originally; about one-third had been washed away. 

 The width at base was about 5 feet (1.5 meters) and the height 27 inches 

 (0.68 meter). The material used was much the same as for the first one 

 described. 



At one place in the bank of a sluggish stream a beaver's refuge hole 

 11/2 feet in diameter was found. This opened beneath the level of the water 

 in the slough and led into a tunnel in the adjacent bank of hard packed 

 sand. The tunnel when opened up was found to be about 10 feet in length, 

 and the upper inner end was 4 feet below the surface of the bank but 

 above the water level in the slough. It contained no nest, nor was there 

 any branching to the passageway. Beaver runways were seen on the bank 

 and there were fresh chewings on the new shoots rising from the trunk of 

 a prostrate willow near by. 



In one place a large 'bed' was found on a bank heavily overgrown by 

 wiUows and other plant growths along the adjacent stream. This bed 

 was about 4 inches in thickness and 5 feet in diameter and was composed 

 of bark which had been stripped off from some large sections of willow 

 trunk which were lying water-logged in the stream near by. 



Beavers when present in a region stand in varying relations to the 

 different persons who are carrying on agricultural operations there. For 

 example, one resident at Snelling considered that the beavers, by raising 

 the water level in the sloughs where their ponds were formed, were of aid 

 to him in that they kept the water-table beneath his land high, and thus 

 secured for him good subirrigation. On the other hand, certain farmers 

 held the animals to be a nuisance, because they persisted in stopping up 

 irrigation ditches. In former years, when the animals were numerous, their 

 damming operations are said to have resulted in the frequent flooding 

 of fields. 



