630 REPORT OF THE COMMISSIONER OF FISHERIES. 



the water in the interior to a height of 2 or 3 feet above that in the 

 surrounding mar.sh. This was here accomplished in the same way as 

 at Port Clinton, except that steam power was used for the purpose 

 instead of gasoline engines. 



The pond then consists of a ditch 7 to 10 feet deep around the entire 

 circumference, the water over the central area having a rather uniform 

 depth of 1 to 2 or 8 feet. The fresh water that was pumped in was 

 originally turned immcdiatel}^ into the circumferential ditch, or could 

 be carried by a wooden flume over into the central area. The first 

 year the pond was used there was found to be great mortalitj^ among 

 the fish, a condition probably due to the large amount of freshly 

 exposed soil with which the water came in contact, so that it became 

 charged with humic acid and other products of organic decay until it 

 was unfit for the fish. This condition continued in spite of the fact 

 that fresh water was continually pumped in, especially during the 

 warmer weather, and it was found later that the water at the bottom of 

 the ditch was very foul and with a bad odor. In the succeeding year 

 flumes were arranged so that the fresh water was carried at once to 

 the bottom of the ditch, and the conditions were found to be much 

 improved. There would probably have been less danger in any case 

 during the second year, as the soil had undoubtedly by that time 

 become very well leached out. 



Here, as in the pond previousl}" described, it was found that the fish 

 gathered around the stream of incoming water, and here also advan- 

 tage was taken of this fact in capturing them. The pond could be 

 drained, if necessary, by changing the elevator over to the inner side 

 of the embankment and discharging the water from the pond back into 

 the surrounding marsh. 



There is one other style of pond in use in this region that should be 

 mentioned, in order to make the present account complete. These 

 have been constructed especiall}^ by the farmers along the southern 

 shore of Sandusky Bay. They are situated on higher ground than 

 those ponds which have just been described, ground that is usuall}^ at 

 least a few feet above the mean level of the bay, and are formed simply 

 by scraping the soil out of an area covering usually not over one fourth 

 to one-half acre, the soil that is removed being used to build the 

 embankments. The water is supplied by windmills or, in a number of 

 cases, by artesian wells. This water would seem not to be well adapted 

 to carp ponds, being cold and strongly mineral, with a vej'y decided 

 sulphurous taste; and j^et the carp are said to do very well in it. As 

 the ponds contain practically no natural food supply, the fish have to 

 be fed regularly to keep them from falling away greatl}^ in weight. 

 For this purpose a variet}^ of things are used, but shelled corn is prob- 

 ably employed more than an3'thing else. In one such pond, which 

 contained about 10 tons of fish, the carp were said to have been fed 



