DEVILS LAKE, NORTH DAKOTA. 21 



rods distant from camp headquarters. The fish when introduced 

 into the car were in excellent condition and manifested no dislike 

 to their environment. On August 12 and 13, when examined, all 

 the fish were in good condition, having withstood a severe storm on 

 the 11th. On August 14 the 3 pickerel and 1 sucker were found 

 dead, with no external or internal injuries to account for the mor- 

 tality. The remaining suckers were found dead in the car on the 

 16th, and again no apparent cause for death was observed. 



On August 16 a supply of about 300 j^ellow perch, from 1 to 

 7 inches long, were obtained from Wood Lake and placed in the 

 live cars. No appreciable mortality occurred among them, the fish 

 were at all times noted to be in excellent condition, and on the de- 

 parture of the Bureau of Fisheries party September 10 all were 

 healthy and active. Up to October 30 no mortality had been re- 

 ported, and the perch retained for observation were in good condition. 

 , Through the Bureau of Fisheries on August 27 Mr. C. M. Fisher 

 received a consignment of young black bass and catfish. From this 

 supply a number of both species of fish were retained for observa- 

 tion, and cars of one-fourth inch wire cloth were utilized for their 

 control, the remainder of the fish being released in the lake. With the 

 exception of a small number that were in weakened condition on their 

 arrival, all bass have thrived under the confinement. Full}^ 95 per 

 cent of the young bass were observed September 10 to be in active, 

 healthful condition. The small nimiber retained for continued obser- 

 vation were reported October 30 to be in excellent condition. Min- 

 nows and sticklebacks were provided for food. 



A fine large specimen of pickerel, collected September 8 from 

 Wood Lake, was found dead at the bottom of the live car September 

 10. An examination failed to disclose any injury or diseased organs. 



Of the catfish received August 27 a few specimens were retained 

 for control purposes, and these were found to be active September 10. 



From the above it may be seen that no deleterious effects of Devils 

 Lake water were to be observed on the yellow perch, black bass, or 

 catfish during the period of confinement, and the same specimens are 

 reported to be at this time in good condition. 



SUMMARY AND RECOMMENDATIONS. 



The physical and biological features of Devils Lake and its 

 neighboring waters, together with data regarding the disappearance 

 of pickerel and its probable cause, have been presented for a general 

 understanding of the conditions in that region. Experiments on 

 the suitability of a number of species of fish for introduction in the 

 lake have also been described. 



