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Part III. — Eighth Annual Report 
animals would rapidly be exterminated. Another argument liable to 
abuse is this : the ratio of the destruction of immature fish by man bears a 
small proportion to the ratio of destruction by natural means, and, there- 
fore, can do no harm. But the destruction of the young by natural causes 
is provided for by nature in the fecundity of the species ; for the degree of 
fertility in a species is as much adapted to the conditions of its existence 
as is the structure of its jaws. We have not sufficient knowledge to 
enable us to state what proportion the ratio of destruction by man bears 
to the ratio of destruction by natural causes. In some cases it is almost 
certainly slight and does not go beyond the margin of waste which nature 
allows. In other cases there is little doubt that, although relatively small, 
it is sufficiently large to disturb the balance, and to decrease the number 
of adults. Each case must be considered separately. 
As has been said, there does not appear to be satisfactory evidence that 
the capture of immature herring, cod, haddock, and most other round fish, 
has had detrimental results. But there is now a concensus of opinion 
that the supply of most of the valuable fiat-fish, such as turbot, brill, 
soles and plaice, has fallen of, in spite of increased efforts to catch them ; 
and it has also been shown that the young are destroyed in large numbers. 
The statistics for past years show that the supply of these fishes has 
diminished. 
I shall therefore not deal here with the question of the destruction of 
immature round-fish, but shall limit consideration to the destruction of 
immature flat-fish by shrimping and beam trawling. 
Shrimping. 
There is ample evidence that shrimping, and especially shrimp-trawling, 
involves the capture of immense numbers of young flat-fish, and the 
destruction of large numbers. The shrimp fisherman works in the zone 
where very young flat-fish abound, and by the present mode of fishing in 
catching the shrimps he must perforce catch the young flat-fish. If it 
were possible to substitute the method used in some places in France, and 
recommended by the French Committee, of using baited traps instead 
of nets (vide p. 186), the capture of young flat-fishes would be entirely 
avoided. 
But how can their destruction by the present methods be dealt 
with ? There is no question here of mesh of net or of avoidance of 
nurseries of young fish. The only satisfactory way of dealing with the 
subject is to ensure that the young fish be returned to the sea alive and 
vigorous. The French Committee state that in France the fish when 
returned perish ; but I have little doubt their destruction may be avoided, 
(1) by hauling the net within a given time; (2) by replacing them in the 
sea within a given time after the net has been hauled. We have not yet, 
however, sufficient knowledge to fix with any precision at all the length 
of time that might be allowed in either case. The vitality of the various 
species of young flat-fishes varies very much, and a length of time which 
might ensure the survival of one kind might be fatal to another.* 
Another point of importance which should, be determined before any 
* I am aware, as Buckland jioints out, that there may be practical difficulties in 
the way of always enforcing such regulations. In shrimping by night, which is 
practised in some places, the men are cautious of handling the shrimps in the dark 
lor fear of being wounded by the sting-fish ( Trachintts iripera). Then there is the 
difficulty of managing the ship and trawl in foul weather, and at the same time pick- 
ing out the young fish. But in the great majority of cases the regulation could be 
carried out without hardship or risk. 
