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FISHERY RESEARCH
3zg
It has reached a length of about one and a half inches and
can swim too rapidly to be captured by the tow—net.
At
this stage the sh
in shoals and their movements
become very hard to follow.
We have no really efcient
instrument for catching them in the open sea, but they may
be caught by shing off sandy shores and in estuaries by
means
of very ne-meshed seine nets.
In fact recent
research points rather to the fact that it may not be
necessary to search in the open sea for the herring at this
stage in its life—history, for it is beginning to
realized
“
that the numbers present in the estuaries are very great
_
and probably quite sufcient to give rise to the large supplies
of adult herring caught by the shermen in the “open sea;
At certain seasons of the year, for instance, the whitebait
that abound in
estuary consists almost solely_
Of young herring (Plate 119).
When the herring
reaches &
length of three or four inches it probably leaves
the estuaries,
and little is as yet known of its movements until it grows
to a size large enough for capture'by the nets. In the case -
of
quick-growing, sh probably the end of the second
year is the time atwhich they are largeenough to appear—for
the rst time in the net catches; the sh would
then be
about six inches in length.
But more usually the herring
are not large enough to be taken in the drift nets until
thèyare-three years old, or at any rate in their third year.
It is difcult to follow the movements ofïthe adult sh;
'
They are too delicate _tobe marked like the plaice. Any
‘
Who has hadled a fresh herring knows h0w easily
the scales come Off and if the sh is returned to;the water
With many of its scales removed
the large surface
of bare
_skin thus exposed s‘oon- becOmes infested w1th:bacter1al
and Other parasites and in a Very
time the ”sh
succumbs.
It is therefore practically impossible to mark.
thé
“any hope of their éurVival'
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