BROWN TROUT 



Salmo trutta Linnaeus 



The brown trout, Salmo truttay originally a native of Europe, has been dis- 

 tributed widely in this country since the latter part of the nineteenth century. 



The brown trout migrate to their spawning areas in late summer and spawn 

 from the latter part of October into February. Like the brook trout they select 

 spring-fed tributaries with suitable riffle areas. Brown trout will, however, 

 spawn in deeper water than the native Eastern brook trout. Since the browns 

 spawn in deeper water their spawning run may be shorter than that of the brook 

 trout. The mature females average about 2,000 eggs per fish. In stream popu- 

 lations the spawning migration may be only a few feet, in lake populations several 

 miles and in the sea-run brown trout the migration may be for many miles. 



Much interest has centered around the so-called "scotch sea-trout" fre- 

 quently taken near Orland, Maine. These "scotch sea-trout" are sea-run brown 

 trout. Few people can distinguish between these sea-run trout and the Atlantic 

 salmon. The red spot on the adipose fin of the brown trout, see color plate, may 

 serve as a field characteristic in distinguishing brown trout from young salmon. 

 Tributaries of Alamoosook Lake such as Power House Brook and Gully Brook 

 appear to have a sea-run population and a resident stream population. 



Attempts have been made to establish the brown trout in some sections of 

 southern Maine. The absence of adult brown trout in the sampling nets of the 

 Maine survey are at least an indication that the brown trout have not been en- 

 tirely successful in most of the areas stocked. 



The brown trout has become popular as the logical successor to the native 

 Eastern brook trout. Apparently the brown trout's ability to withstand higher 

 temperatures, ranging from 76 to 80 degrees Fahrenheit, together with its greater 

 tolerance of pollution are responsible for the success which it has enjoyed in some 

 states. Best management practices would not introduce the brown trout into 

 drainages occupied successfully by either the Eastern brook trout or the rainbow 

 trout. Brown trout grow rapidly and at the expense of any other species which 

 might be present. 



Most trout, including all the species found in Maine, grow much faster and 

 larger when they are in a lake than in a stream. The following total lengths in 

 inches of brown trout give some indication of the age and growth and also allow 

 a size comparison between stream and lake fish. 



Young brown trout feed on minute animals and small aquatic insects. As 

 they grow older and increase in size they turn more and more to a diet of fish. 

 The larger the trout the more fish he consumes. 



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