I900.] Notes. T85 



FISHES. 



Attempted Introduction of the American Shad Into Irish 



Waters. 



It was announced in a recent issue of a Dublin daily paper that Mr. 

 Moreton Frewen was about to deposit 100,000 eggs of the American vShad 

 (^Clupca sapidissiDid) in the River Shannon. On my appl3-ing to this gentle- 

 man for further information, he wrote to say that he regretted that the 

 consignment of Shad ova had all perished on their way to Ireland, but 

 that he hoped to make a further trial. As it is probable, therefore, that 

 we shall soon be able to add the American Shad to the list of fishes 

 inhabiting Irish waters, a few remarks about this fish may be of interest 

 to the readers of the Irish Natitralist. 



In the first place it is perhaps not generally known that we already 

 possess two different kinds of Shad in Ireland. These, like the Salmon, 

 are marine fish which ascend rivers for the purpose of spawning, and in 

 some parts of Ireland (particularly on the Atlantic coast), they seem to 

 be fairly abundant' They are closely allied to the Herring, belonging to 

 the same family {Clupeidix). That they are not highly esteemed as food 

 in Ireland is indicated by the term " bony horses " often applied to them. 

 In England they are known as Twait vShad and Allis Shad. In this 

 country the term " bony horses." "bony horsemen," or " rock-herrings" 

 is probably applied indiscriminately to both species. 



From a zoological point of view the introduction of foreign species of 

 animals, unless they can be kept within proper bounds, must be looked 

 upon with disfavour, and should be discouraged. In most cases the 

 artificial introduction of species has not proved a blessing, while many 

 introductions have caused enormous financial losses to the countries 

 which they were supposed to benefit. vSuch introductions frequently 

 produce a disturbing influence upon the native fauna, and great caution 

 should therefore be exercised in adding new members to it. 



Moreover, it is almost certaii: that Irish people w^ould not take very 



readily to the American Shad, although it is said to be a much finer 



flavoured fish than our own. I do not know whether Irish rivers contain 



very much more food than our 3'oung Trout and Salmon require. If not, 



the latter would have to divide their daily rations of small Crustacea and 



insect larvae with the newcomers, who, at any rate, would never possess 



the same commercial value as Salmon and Trout. 



It might however be argued (as Mr. Frewen has done very ingeniously 



in the NinetcciUJi Ceiilury, vol. 46, 1899, p. 399), that the Shad fry would 



be invaluable as a food supply'for our older river Trout and Salmon smolts, 



so that the great depredations of the latter fish amongst their own kind 



would be avoided. 



We look forward to Mr, Moreton Frewen's experiments with great 



interest, and hope that he may be correct in his supposition that the 



introduction of the American Shad will prove of very great benefit to 



Irish fisheries. 



R. F, SCHARFF. 



Science and Art Museum, Dublin, 



