CHAPTER V. 



POACHERS. 



Definition of 

 term poachers 

 as used here. 



NDER the comprehensive title of 

 poachers there are included here all 

 the Vertebrata that prey upon the 

 fish. Perhaps, too, some few of the Inverte- 

 brata ought to have been treated under the 

 same heading. One of them, the large water 

 beetle {Dytiscus marginalis) , certainly in the 

 larval stage and possibly the mature beetle, 

 preys upon the fry and yearlings. At the 

 moment of writing I have the clearest evidence 

 of this in the shape of a naturally bred yearling 

 trout and a Dytiscus larva preserved in spirit. 

 When taken the unfortunate yearling was dead, 

 and the voracious larva was attached to the 

 lower side of its abdomen, close behind the 

 pectoral fins. In its death struggles the larva 

 managed to disengage itself from the flesh of 

 the trout, which was deeply scored by the 

 formidable mandibles of the beetle. According 



