36
THE BIOLOGY OF FISHES
The extentof the wanderings of the Plaice inthe North
Sea and Channel is very limited.
In the latter a few small
hays have a population all to themselves ; the Plaice seldom
'
wandering beyond. In the North Sea the areas appear to
be greater, owing probably to the wider expanse of shallow
__Ï
grounds.
Thus there appears
to
be only one race or
population for the whole of the southern North Sea and ’
_
an0ther for the northern parts, but even among these there
may be local communities.
-
In Icelandic waters, where the depths near the coast are
;
much greater than in the North Sea, the wanderings of the
1
Plaice appear to have amuch greater range. - A number of
'
Ï
specimens marked by ]ohs. Schmidt on the eastand north
coasts were --retaken later up
to
away, moving
,
toWards
west and «south, and the distance actually
,_
travelled was probably much,
In these waters the
’Plaice‘ spawn, it*—is said, only on thesouth and West coasts,
and… the fry appear to be carried much longer distances
round.the north to the east coast, probablÿbWigt0 the '
slower‘rate of devel(3pment in the colder waters—. A curious_
thing, if this interpretation is correct, is that on
:
to the west and south coasts to spawn, the Plaice of the north
coast travel backwards along the north coast, whilst those
of the east take a shorter route along the south. Thus the
»
latter appear to make a complete circuit of Iceland. Whether
;
the-adult Plaice make annual wanderings of this extent——
…
j_urSt;as they;wander out and in yearly in the North Sea and
Channel—1snot (clear. So far as the observations go, it
_
wouldappear thatthePlame of Iceland have adopted quite
.
differetl—habitséfrom thoseîof the North Sea.
'
’
_
ï
NorWes'giar‘1 waters the Herringand Cod have also
wanderings. Thus,twhilst
,
,
denite areas of the
_
the'Heri-ing, and?the
_“
*—-Ï
_
”
ÇO_d,:cthez—.sherièë at other fseasons eXte‘nd
Ç
i‘
the-north to the
‘
;5 SkagerRak in thesouth The ::}egîgs and
_
*ÿoungest stages
some Over— the