10 U. 8S. BUREAU OF FISHERIES 
eatch. For example, the very poor fishing in 1930-31 was preceded 
by 3 years of very low scrod catches. 
The commercial fishery does not appear to be the basic factor in 
fluctuations; it serves rather to accelerate the mortality rate and 
thereby to rapidly decimate a year class once it has reached a size 
that can be captured by the commercial otter trawls. Such a con- 
dition obtained during the 1924-29 period, when the annual landings 
from Georges Bank increased from 70 to about 220 million pounds. 
This intensive fishery, combined with a series of poor spawning 
seasons from 1926 to 1928, resulted in a precipitous decline from peak 
abundance in 1927 to the low point reached in 1931. Since 1931 there 
has been a gradual improvement on Georges Bank, due to the rela- 
tively buecesethl spawning seasons in 1929, 1931, 1932, 1933, and 1934, 
and to the fact that the commercial fishery on Georges Bank has been 
much reduced, averaging for 1932-36 about 72 million pounds, com- 
pared to 170 million for the 1927-31 period. 
The Nova Scotian Banks (Area X XI) remain the least understood 
of our major fishing grounds. Practically nothing is known about 
the distribution or abundance of young haddock below commercial 
size in this area. There appear to be considerable differences between 
the populations in the eastern (Banquereau), central (Sable Island 
and Emerald), and western (Browns) parts of the area, at least for 
the scrod sizes. Variations in abundance of the Browns Bank popu- 
lation appear to be determined by different factors from those that 
control the population about Sable Island. F ‘or instance, in 1933 when 
scrod became so abundant in the latter region, they were found in 
but moderate numbers on Browns Bank. Later, in 1935-36, the 
average catch per unit of effort of all haddock gradually declined in 
the Sable Island region while on Browns Bank it experienced a marked 
increase. 
Area X XI was not extensively fished by the New England otter- 
trawl fleet until 1933 and 1934 when the abundant year class of 1929 
reached commercial size and caused an eightfold increase in the scrod 
catch. In 1935 and 1936 the scrod catch rapidly declined, while the 
catch of large haddock increased 70 percent as the 1929 class grew 
from scrod to lar ge haddock. The rapid decline in the scrod catch 
indicates that the year classes of 1930, 1931, and 1932 were all poor or 
failures in this area, in contrast to Geor ges Bank where the classes of 
1931 and 1932 were relativ ely abundant. 
Observations and study of the fishery were continued during 1936 
under the direction of W. C. Herrington assisted by J. R. Webster 
and H. M. Bearse. Field observations consisted of work on the Boston 
Fish Pier and one trawling trip on the Atlantis in April to Georges 
Bank, South Channel, and the southwestern part of Browns Bank. 
The Fish Pier detail was covered principally by H. M. Bearse who 
obtained data providing an accurate record of fishing time, position, 
and other relevant information on all groundfish trips landed at that 
port, as well as length and scale samples from the haddock catches. 
Observations include 2,900 interviews, 87,000 length measurements, 
and 3,339 scale samples. The Atlantis trawling trip was made to 
obtain material for the study of abundance, distribution, and growth 
of 1-, 2-, and 38-year-old haddock which are below marketable size and 
cannot be obtained from the commercial catch. On this trip 107 hauls 
