5 
In order to obtain a knowledge of our herring shoals after 
war conditions, a scheme of work was drafted in 1919, and samples 
were examined from Stornoway and the Shetlands, north coast 
of Scotland and south to Yarmouth. With the help of the Depart- 
ment of Agriculture and Technical Instruction for Ireland it was 
possible to extend the investigations into Irish waters in the 
following year. The samples examined have been reported on 
in previous papers, and from their age composition it is possible 
to make the following statement. 
From the north-west of [reland, the north of Scotland and 
the Shetlands, and south to Yarmouth, the year-classes of 1913 
and 1914 were good; the 1915 year-class was poor ; and the 1916 
year-class was fairly good. In other words, the hydrographic 
conditions over the whole of these waters had been such that they 
had had the same effect on the herring population. 
The catches made in 1920 and 1921 and the comparatively 
small numbers of the 1917 and 1918 year-class found in the samples 
from other than summer feeding shoals point to the 1917 and 1918 
year-classes being poor. . 
The age composition of some of the samples examined was 
as follows :— 
YEAR-CLASS. 
Locality. Date. 1518) 1917. L9G: 1915. VO WOES. W912. LOTT. 
Bunecrana ... Ana ey 2A | 5 29 ily 8 20 2 5) 1 
Stornoway ... ve. 20/2/20 — 28 25 i 116) 21 2, 1 
Lerwick Aor meet oh 2208 —— 1 15 8 44 2d D 1 
Yarmouth ... ... 20/11/20 — 4 30 10 il 17 11 on 
* 2 per cent. 1910 and 1 per cent. 1909 year-classes. 
It is clear from the above that the herring fishery depends 
upon widespread conditions, and a consideration of the 1904 
year-class will show that not only are the herring fisheries about 
the British Isles at times governed by the same conditions, but that 
the whole of the North Atlantic is involved, and that some local 
changes may take place. 
THE 1904 YrarR-cLass.—CANADIAN Waters.—Lea* from an 
examination of samples from Canadian waters has been able to 
prove that the herrings of the northern waters of the Gulf of St. 

* Report on Age and Growth of the Herrings in Canadian Waters. Canadian Fish. Exped, 
1914-15. 
