It is suspected from our observations to date, that the 

 streams of Wisconsin and Minnesota (although less suitable than 

 those in Michigan) can support spaiming runs of considerable size. 

 The 1952 survey of the streams of Wisconsin was inadequate insofar 

 as it told us little about the productive potentials of the streams, 

 and nothing about the actual extent of utilization of the streamsj 

 little control ifork of any nature is possible in this area until a 

 great deal more information is gained. 



The inadequacies of the survey of the strecons of the 

 Minnesota area V3re the result of the ejrt.renie rapidity of the sur- 

 vey, and the probability that sea lampreys are not utilizing the 

 streams to the extent which they may in the futtire. In any event, 

 no lampreys or nests were found. The actual evaluation of the im- 

 portance of the streams is based on single excminations. Generally 

 speaking, it is doubtlHil if many of the streams considered to have 

 a large productivo potential (room for 75 or more nests) can pro- 

 vide room for nests in the qus-ntities (several hundred nests or more) 

 already observed in scae of the streams of eastern Lake Superior or 

 Lakes Huron and Michigan, Even in the 22 streams considered to be 

 the most favorable of the 156 examined, areas for hundreds of nests 

 are probably not available. Ho;jever, construction of as many as 75 

 nests in any single stream will (if spasming and survival are success- 

 ful) denand serious control operations. 



A number of the 22 favorable streams contain spasming 

 habitat for less than 75 nests, smd have a medium productive poten- 

 tial; it is likely that lampreys will spawn more successfully in 

 these streams than many others vdth a large productive potential 

 (productive potential is based upon the number of nest sites avail- 

 able and not the final production of the stream in adult lampreys, 

 since the latter is more or less an unknovm quantity; i.e. a stream 

 with an area suitable for 25 nests and possessing favoraEle tempera- 

 tures will be suitable for lampreys, whereas a stiream with room for 

 125 nests with temperatures hovering ar-ound the minimum spavming 

 temperature of 53 to 56 is likely to be unfavorable much of the time 

 at least). 



I have been asked to list the 22 most favorable Minnesota 

 streams in the order of their importance, and from an efficient 

 initial control operations standpoint (i.e. in which streams should 

 the first control structures be constructed?). The listing is, of 

 course, an educated guess; the order has been influenced by the rela- 

 tive productive potentials, the general favorability, the size of 

 the streams, and the probable relative difficulties which irill hin- 

 der construction, maintenance, and operation of control structures, 

 (Lampreys have been observed in the Sucker and Knife Rivers in re- 

 cent years but their presence has not been used as a criterion for 

 intitial control, since lampreys are also probably present in some 

 of the other streams.) The suggested order of construction is as 

 follows: 



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