230 
BULLETIN OF THE BUREAU OF FISHERIES 
races taken during the progress of the summer fishery is dependent. The spawning 
habits may be one of the limiting factors of their abundance; and the extent of the 
spawning grounds, and the number of spawners present, from time to time, may give 
some rough idea of the actual abundance of the herring. Overfishing should manifest 
itself by a decrease in the quantities of mature fish, consequently the spawning grounds 
should be the first to feel the effects of depletion. 
The age at which the herring reach maturity has a direct influence on the amount 
of strain that the fishery will bear; in some fishes, as the halibut, where maturity is 
reached long after the fish are of a size to enter the commercial catch, there is no 
breeding stock that is not drawn upon by the fishery. 
The preliminary nature of this report should be clearly kept in mind. In some 
cases the data are sufficient to warrant fairly definite conclusions, but in other cases 
the data are few and are presented for whatever they may show. This study will be 
continued indefinitely, and it is hoped that future contributions will fill in gaps and 
amplify the data now presented. 
DESCRIPTION OF THE FISHERY 
THE SEINE FISHERY 
The methods of fishing have undergone considerable modification since the early 
days of the fishery. At that time beach seining was the method most commonly 
used by the small operators from Petersburg and Juneau. The only large company, 
that at Ivillisnoo, on upper Chatham Strait, used an old Norwegian method in which 
a large seine was placed on two boats, with about eight men per boat, the two rowing 
about 20 to 30 feet apart. When a school of fish was discovered they rowed around 
its opposite sides and pursed the seine by hand from one boat, brailing the haul into a 
steamer. Capt. Elling Arentsen used this type of gear for one of his boats at Big Port 
Walter until 1927. The seine was 14 fathoms deep and 175 fathoms long, with 1%-inch 
mesh, stretched measure. 
Soon after 1900 the small operators of Petersburg and Ketchikan commenced 
using purse seines from power boats. This method of seining did not immediately 
supplant the Norwegian method of seining from row boats, which was continued by the 
Killisnoo plant until about 1924, and by the Big Port Walter plant until 1927. By 
1918, however, the majority of the operators in southeastern Alaska, and all of those 
in the newly exploited fisher}^ in Prince William Sound were using the power seine 
boats. 
In 1918 the power seine boats in southeastern Alaska had an average net tonnage 
of 17, ranging from 11 to 31 tons. They were all powered with gasoline internal- 
combustion engines and carried a crew of from five to seven men. In 1927 in south- 
eastern Alaska the purse-seine boats had an average net tonnage of 31, ranging from 
20 to 42 tons, the smaller sizes having lost favor owing to their small carrying capacity. 
One-half of the present fleet (practically all of the newer boats) is powered with 
Diesel engines to cut the cost of operation. Each boat carries a crew of from six to 
eight men. 
The purse seines employed at present range from about 175 to 250 fathoms in 
length and from about 12 to 30 fathoms in depth. The webbing comes in strips 3% 
fathoms in width, so that the depth of a seine is easily changed by adding or taking 
off a strip. In the early summer, shallow seines of 4 or 5 strips are used, but in the 
autumn the fishermen usually have to deepen them in order to make good catches, 
