214 



BULLETIN OF THE UNITED STATES FISH COMMISSION. 



Lampreys must be destroyed before spawning if they are to be exterminated. Nothing would !><> 

 easier than to do this. A dam with a fishway the lishway leading into an isolated inclosure \\ ln-iv 

 the lampreys could be easily removed and disposed of, or a weir of some kind, could be constructed at 

 Blight expense. If this rould be continued for three or four years in all the lakes and in the Oswego 

 River, the race could be extinguished and the lakes wholly freed from their devastations. 



In the diagram A represents perpendicular posts set in the stream and fastened, for the purpose 

 of catching floating material that might otherwise tear or injure the weir below. B represents net 



wings for the capture of creatures running down the stream. 

 C represents the main or chief net placed entirely across the stream 

 to prevent passage either way. At D is the pocket or pen in 

 which the fish coming up the stream will ultimately be found, 

 being guided by the various wings of netting or wire K and F. 



It can be seen that if a weir for this purpose were 

 established in the inlet of Cayuga Lake, not only would 

 it do a great deal of good in removing the lampreys, 

 but what is much more, it would give some vastly im- 

 portant absolute facts to the State authorities upon 

 which they may be able to definitely base plans and cal- 

 culations for more extensive operations at other lakes 

 for another year. Also, one can scarcely estimate what 

 a valuable amount of scientific information would be 

 gained concerning our anadromous fishes as they run up 

 the stream to spawn and return to the lake again. Im- 

 portant investigations could here very easily be made, 

 and many valuable facts could be gained by such inves- 

 tigations properly conducted. Until trained investiga- 

 tors give our legislators many facts not now known, 

 laws that will prove effectual in the protection and 

 maintenance of fish or game can not be enacted. 



For example, the laws for the protection of fish are 

 in most cases based upon their spawning habits, and 

 this is of course right; but no one can give or find cor- 

 rect answers to the following questions for even one- 

 fourth of the number of kinds of fish found here: 



Just when do they commence to spawn, and when 

 is the spawning completed? How long before spawning 

 do they run up the streams, and how long after do they 

 return to the lake or sea? Just what species find it 

 necessary to run up the streams for spawning, and what 

 remain in the lake! What is their food, and what their 

 enemies and diseases at tin's most important time in the 

 life of the fish? What is their nmdilication in structure, 

 or condition of all organs, and their food before, after, 

 and during spawning! In what numbers do they run up the streams, and what 

 proportions are males or females? What kind of nest do they build, and do both 

 sexes take part in its construction ? Which sex cares for the eggs, and which for the 

 young, and how? And, how long do the young need or receive parental protection I 

 All of these questions and many others that could be asUed ;ne of great impor- 

 tance, brt can never be answered except through some such careful investigations as 



Diagram of woir for catching lamprey* 

 a,i tliry run up the Htream to apawn. 

 (Arrow iinli :it. s direction of current.) 



