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scarce. Even on the fishing grounds between Port Victor 

 and Kangaroo Island, and in the vicinity of the latter, fish 

 in any quantity are obtained with increasing difficulty. These 

 statements apply not only to schnapper, but to' many other 

 kinds of fish, the sweep, for instance. Ten years agO' it was 

 easy anywhere two or three miles along the coast west from 

 Port VictoT, on a suitable day, to secure good bags of this 

 valuable fish ; now this happens only occasionally, and the 

 fish are smaller. I have noticed also that other varieties of 

 fish which haunt the rocks and which were occasionally caught 

 by rod and line, are now rarely secured at all. Even the 

 mullet, though they are still caught in lai'ge numbers, are 

 gradually becoming less plentiful, and thei fishermen on the 

 south coast complain more and more of the uncertainty of 

 securing good hauls in the season. It is not easy at first 

 sight to account for this falling off, considering the great 

 stretch of ocean on the east, south, and west of us, especially 

 when it is remembered that fishing on a large scale, if it can 

 be called a large scale, has only been going on for about 50 or 

 60 years, and in many places, on our south coast, for example, 

 for much less than that. If we examine a particular case, 

 say that of the sweep already mentioned, we find that it is a 

 fish taken entirely by line, and, generally speaking, in very 

 calm weather only, so that there is no rapid destruction from 

 any ordinary cause. In the neighborhood of Port Victor 

 there is practically no pollution of the water, no disturbance 

 by ocean traffic, and as we ha^ve seen there can be no whole- 

 sale destruction of the fish by man. Large numbers of the 

 young fish still hannt the coast, and they are found in almost 

 every rock hole which is washed by the ocean. Wliy, then, 

 should there be such a falling off? Does this fish take so 

 long to reach maturity that the catching of the larger ones in 

 a particular locality leaves a gap which years of protection 

 will be necessary to fill up? Is their food supply running 

 short? Are they being prevented in any way from gaining 

 access to their proper spawning grounds? Is the balance of 

 life being disturbed in such a way as to involve the destruc- 

 tion of large numbers of the young fry? Or are all these 

 causes contributing to the result? One would naturally sup- 

 pose that some disturbance of the balance of life is the most 

 probable cause, but such distiu'bances, though genera^lly easily 

 followed on land, are by no means so easily traced among 

 marine animals. A writer in the "Contemporary" for July, 

 1901, to whom I referred in my previous address, gives in- 

 teresting particulars bearing on this point with reference to 

 the fish on the English coasts. According tO' his statements. 



