Oshurn. — Conditions Detrimental to Bass. 45 



millions of young fry for the purposes of distribution without in any way 

 depleting the natural resources of the lake. In the case of the small- 

 mouth bass the situation is a little more difficult in Ohio because we get 

 them almost entirely in the streams; the lakes, aside from Lake Erie, are 

 as a rule too warm for the small-mouth. 



Mr. Titcomb: One point that cannot be too strongly emphasized 

 is the seriousness of the depletion caused by the taking out of bait fish 

 by the angler. In some of our lakes the minnows are practically gone, 

 and we have to introduce minnows, along with our other work, in 

 connection with the reservoirs. 



Dr. Osburn: That was true around Sandusky and Put-In-Bay this 

 summer; there was no live bait to be had. In the seining about Put-in- 

 Bay harbor for study purposes I could always get some, but not anything 

 like what we should be able to get. Where v/e could formerly get 

 large numbers of minnows we can now only get a few, so there is no 

 question that there has been a great depletion. It can not be attributed 

 to pollution in streams whei'e no pollution exists. The condition may 

 be due in part to other factors than seining, — the cutting out of 

 shelters and the elimination of the forests, the latter resulting in the 

 streams going so low that they will not maintain even the smaller fish 

 during the lowest water of the season. That is a great check on the 

 production of our small fish as well as of our larger rough fish, suckers 

 and so on, which are no longer found in streams where they used to be 

 abundant. I suppose the same conditions exist all over the country 

 where it is thickly populated. 



Mr. Hare: Which of the two basses, the large-mouth or the small- 

 mouth, is more susceptible to that parasite which you term the grub. 



Dr. Osburn: I have not found any paticular difference in Ohio 

 waters; both are susceptible to it. I do not believe we have as much 

 trouble with it in our state as they do in some Canadian waters, judging 

 by reports. 



Mr. Hare: Does it depreciate the value of the fish to any consider- 

 able extent? 



Dr. Osburn: When they are numerous enough they make the fish 

 unfit to eat, but it is uncommon in the waters of Ohio that the fish should, 

 from this cause, be unfit for food. 



Mr. Hare: Is this parasite more prevalent in warmer than in 

 cooler waters? 



Dr. Osburn: I do not think so. I have not made comparisons of 

 this in Ohio, but you will find them both in the small-mouth bass in Lake 

 Erie and in those in the streams in the southern part of the state. 



Mr. Buller: May I supplement your remarks in reference to the 

 disappearance of the minnow by stating the conditions which, in our 

 judgment, were the cause of the disappearancee of minnow life from the 

 forest streams in Pennsylvania? It was reported by our officers that 

 bait fishermen who v>ere fishing for minnows would pull up, say, a 



