and there are indications that turbidity changes 

 the behavior patterns of fish. Excessive sedi- 

 mentation smothers game fish eggs and bottom 

 dwelling insects. 



Northern Pike, Paddlefish 

 and Brown Trout 



Although Montana is known primarily as a 

 trout state, northern pike and paddlefish as 

 well as one of the trout species (brown trout) 

 made history during the biennium. 



The success on northern pike was scored at 

 Fort Peck Reservoir and was made possible 

 by rising water levels from 1962 to 1965. North- 

 erns are spring spawners that seek vegetation 

 in shallow water or marshy area on which 

 they spread their eggs. Conditions were just 

 right in the springs of 1963, 64 and 65 for 

 northern pike spawning and for the production 

 of forage fish which they feed upon. The north- 

 erns thrived and fishing was excellent during 

 the biennium. Twenty-pounders were not un- 

 common in the catch. 



Shoreline seining was used to assess north- 

 ern pike reproduction in the reservoir. In an 

 October 1965 sampling, an average of one 

 young-of-the-year northern was taken for each 

 30 feet of shoreline seined. It is not known if 

 this was the average for the entire 1,600 miles 

 of shoreline, but there is no question that na- 

 ture was bountiful. It is predicted that Fort 

 Peck Reservoir will be one of the hottest spots 

 in the west for northern pike for several years 

 to come. 



Montana records for paddlefish were broken 

 during the biennium. In fall of 1964 the small- 

 est paddlefish ever reported to the Fish and 

 Game Department as being taken from Mon- 

 tana waters was netted from Fort Peck Reser- 

 voir by commercial fishermen. This diminutive 

 "paddler" was about 8 inches long and nearly 

 half of that was proboscis. The following spring, 

 a 129-pound paddlefish, the largest recorded 

 for Montana, was taken by snagging from 

 the Missouri River south of Malta by a Billings 

 sportsman. 



Paddlefish are not newcomers to Montana. 

 In fact they may be the "most na'ive" of the 

 state's native fish as their remains were found 

 in 63-million-year-old fossil beds north of Jor- 

 dan. Knowledge about the species is scarce 

 considering it has been around so many years 

 and most of the life history information we 

 have is from other states. 



A study was launched at the start of the 

 biennium to answer questions about paddle- 

 fish in Montana their migrations, age and 

 growth rate, and extent of fisherman harvest. 

 A total of 1,146 paddlefish were tagged. The 

 capture and release site for most of these was 

 the Yellowstone River near Intake. Tag re- 



turns show that they moved considerable dis- 

 tances both up and downstreams. 



The age study showed paddlefish taken near 

 Intake were 4 to 25 years with the majority 

 being 7 to 12. Fort Peck Dam blocks the up- 

 stream migration of paddlefish from below on 

 the Missouri and it was found that the paddle- 

 fish population in the Missouri River above 

 the reservoir had an older age structure than 

 those on the Yellowstone. On the Missouri, 

 most were 18 years old or older. Since male 

 paddlefish do not usually mature until they 

 are 7-8 years old and females until 10-12, the 

 population being harvested at Intake is com- 

 paratively young. 



The combination of tag returns and age data 

 leads investigators to surmise that Garrison 

 Reservoir, North Dakota, is the source of pad- 

 dlefish caught at Intake. This large impound- 

 ment was finished in 1953 and while filling 

 it probably provided ideal habitat for young 

 paddlefish. The filling of Garrison Reservoir 

 and the formation of the large group of 7-to-12- 

 year-old paddlefish at Intake correspond ex- 

 actly. If this conjecture is correct, future pad- 

 dlefishing at Intake depends upon the continued 

 suitability of Garrison Reservoir as a nursery 

 area. If conditions remain favorable the runs 

 will occur each spring. If conditions become 

 unfavorable the runs will gradually fade out. 



The Montana record weight for brown trout 

 was broken during the biennium when a fish- 

 erman from Three Forks caught a 29-pound 

 brown trout at Wade Lake near West Yellow- 

 stone. Many of the "bragging" size fish caught 

 in Montana are brown trout. They have proven 

 their ability to withstand continuous fishing 

 pressure and to maintain their populations 

 through natural reproduction. 



Alva Lake and Inez Lake 

 Rehabilitation 



During the bieimiuiii the fourtii phase of the 

 management plan for the Clearwater River 

 Drainage was completed. Phase 1, construc- 

 tion of a fish barrier at the outlet of Rainy 

 Lake, was completed in 1957. Phase 2, chem- 

 ical treatment of waters above this barrier to 

 eradicate non-game fish, was completed in 

 1958. The waters were restocked with native 

 cutthroat trout and excellent fishing resulted. 

 Phase 3, construction of a fish barrier between 

 Alva and Inez Lakes was essentially completed 

 in 1963 with finishing touches added in 1964. 

 Phase 4, chemical treatment of Alva and Inez 

 Lakes and the drainage, demarcated by the 

 two fish barriers, was completed in September 

 1965. Initial restocking of this area with cut- 

 throat trout was accomplished in December 

 1965. 



The Clearwater is the only drainage in 



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