66 



EEASONS FOR THE INTRODUCTION OF THE 

 PERCH INTO TASMANIA. 



By Morton Allpoet, F.L.S., F.Z.S. 



As many persons in this and other Australian colonies 

 appear to consider that the perch introduced into the colony 

 will prove injurious to other and better fish, it may be well to 

 place upon record the reasons for such introduction. 



The rivers of Tasmania are divided into two very distinct 

 classes, namely, those which are ever flowing, and take their 

 rise in mountain streams or large lakes, and those which only 

 run during the winter months, and in summer consist (like 

 many Australian rivers) of a series of deep still pools. The 

 first class are admirably adapted for the rock and rapid loving 

 salmonidse, while the second form a suitable home for com- 

 paratively still water fish, such as perch, carp, and tench. 



The differences in these two classes of rivers are well 

 marked by their indigenous inhabitants, the lively grayling 

 (Prototroctes murcena), closely approaching the salmonidae in 

 character, being present in the first class and absent in the 

 second. The Derwent, South Esk, and Huon, and many of 

 their tributaries, are good examples of the one class — the 

 Macquarie, the Jordan, and the Coal River, of the other. No 

 sensible man would compare salmon or trout with perch, but 

 while there are in Tasmania hundreds of miles of rivers, and 

 acres of lagoons and backwaters devoid of good indigenous 

 fish, which will not produce salmon and trout, and will produce 

 perch, surely the latter fish ought not to be altogether 

 excluded. 



Whenever they become numerous the perch will doubtless 

 find their way to the rivers which produce better fish, but it 

 must be remembered that in any given river the localities 

 suitable for trout and salmon in the early stages of their 

 growth are by no means those frequented by perch, and if the 

 perch should occasionally swallow a few hundreds of young 

 salmon or trout, the old salmon and their congeners will never 

 forget to return the compliment on a far larger number of 

 perch which produce young in such numbers as to supply a 

 vast quantity of valuable food, and it is an undoubted fact 

 that the salmon and trout do more injury both to spawn and 

 fry of their own species than the perch. 



In numberless rivers, salmon, trout and perch, are all 

 indigenous, and each would be plentiful if fairly treated by 

 their worst enemy, man. 



