506 
ical (anon., 1954; Pickard and McLeod, 1953) 
and geological data (Dawson, 1880, 188 li, 
1881 b, 1888, 1897; Bostock, 1948) have been 
referred to in the literature. Earlier biological 
observations and collections, which form part 
of the background for this paper, were made in 
the area in 1946 (anon., 1947, 1948^) and 1947 
(Scagel, 1948). The results of a study of the 
phytoplankton and zooplankton collections 
which were also made during the same cruises 
will be presented in a subsequent paper. 
GENERAL ECOLOGICAL CHARACTERISTICS 
OF COASTAL REGION 
The Pacific Coast of Canada is ideally suited 
to a study of benthonic organisms and the effect 
of oceanographic factors on their distribution 
both in the intertidal and the sub tidal zones. 
Although the coast of British Columbia (Fig. 
1) is only about 600 mi. long, proceeding di- 
rectly from the Strait of Juan de Fuca to Dixon 
Entrance, if all its various ramifications are in- 
cluded there is a coastline estimated at about 
16,900 mi. in length. The tidal amplitude in 
this region is great, ranging from about 11 ft. 
at the southern boundary to nearly 26 ft. at the 
northern boundary. As a result of thorough mix- 
ing in the coastal region the upper zone in this 
area, except for a few local anomalies, is char- 
acteristically rather uniform in temperature at 
any one period and fluctuations occur within 
narrow limits. The annual range in temperature 
of the seawater near the surface is from about 
6° to 18°C On the other hand, because of the 
runoff from large rivers, especially through the 
long mainland inlets, there are conditions rang- 
ing from practically fresh water at one extreme 
to full ocean salinity of about 34 %o at the other. 
Throughout the coast the physical nature of 
the substratum, ranging from mud and sand at 
one extreme to solid rock at the other, deter- 
mines to a large extent the organisms which 
are found in a specific area. However, a com- 
parison of the flora and fauna on various types 
of bottom is possible in a number of regions 
which are otherwise oceanographically rather 
similar. This permits a correlation of the dis- 
tribution of a wide variety of plants and animals 
with other physical and chemical factors of the 
environment. The oceanographic conditions 
PACIFIC SCIENCE, Vol. XV, October 1961 
characteristic of the coast provide an ideal area 
in which to study the distribution of marine ben- 
thonic organisms particularly in relation to 
salinity over a rather extensive geographic area. 
GEOLOGICAL CHARACTERISTICS 
General Coast Features 
The Coast Mountains of British Columbia, 
which run along the whole length of the prov- 
HOUR OF DAY (PS.T) 
Fig. 15. Fluctuations in temperature, salinity, and 
oxygen at various depths near the Klucksiwi River at 
station 21 (1953). 
