470 SALMON AND TROUT. 
difficulty in breeding grayling artificially than was formerly 
supposed. The principal risk is owing to their spawning 
operations being got through in such a short time. If the 
right day is missed, the fish may have finished, and no ova 
can be obtained. Young grayling can be reared in nursery 
ponds with as little trouble as trout, and they thrive on exactly 
the same food. 
It remains to give a caution against over-stocking, which, as 
a practical writer truly observes, will produce ‘a sort of perma- 
nent famine.’ A stream should never be fully up to its possible 
‘limit in regard to stock, a little under will give you bigger and 
better fish.” At the same time it is an undoubted fact, that 
there are very many waters which (if managed properly) would 
contain with perfect safety ten times the number of fish they 
now do. 
Let me, in conclusion, draw attention to some of the 
enemies of trout. 
In the natural state the parent fish devour the ova as 
soon as it is deposited. Only to-day I saw a pair of Fontinalis 
about four pounds each on the spawning beds, and watched 
them for some minutes. Every time the female deposited a few 
eggs, both she and her ‘consort’ turned round and devoured 
them instantly. Yearlings and older fish lurk in the vicinity 
of the spawning grounds, and devour every egg they can find. 
Swans,' geese, wild and tame ducks, moor-hens, dab-chicks, 
cootes, cattle and rats, rout about the spawning beds, and 
the later spawning fish disturb the ‘redds’ previously made. 
Nature is bountiful enough to provide for considerable waste, 
but this is no reason why art should not step in and reclaim it. 
It is only in places possessing a very large extent of natural 
spawning and rearing ground that any great number of store 
fish are to be found. In some of the finest reaches of water 
one sees but a few dozen yearlings to replenish the river by- 
and-bye ; the natural consequence of this being, that in two or 
1 A swan will devour the best part of a gallon of trout ova in a day, say, 
40,000 eggs. 
