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PACIFIC SCIENCE, VoL XXI, July 1967 
Latitudinal Range of Probable Spawning in: Coastal l\ \ \ \ \\ : Inland K// / \ : and Both IX yVSAl Forms. 
State of Maturation: VII = Near Spawning, VIII- Spawning Imminent, Eggs and Sperm Flowing,' IX= Spent. 
Fig. 6. Monthly mean temperatures in °C arranged by latitude for coastal and inland localities encompass- 
ing the distributional range of Cottus asper. Solid or unfilled vertical bars, left side of each panel, indicate 
actual ranges of latitude over which specimens have been found in a given state of maturity. Temperature 
values after Krejsa, (1965:109). 
or eggs have been collected from them during 
the following dates: March 7 to May 10 in 
Little Campbell River (122° 46' W) ; March 
25 to April 15 in South Alouette River (122° 
35' W) ; and April 30 to May 27 in Squakum 
Lake (122° 00' W). 
DISCUSSION 
The present study confirms the existence of 
a downstream spawning migration of the prickly 
sculpin in the Little Campbell River. It not only 
documents the occurrence of intertidal spawn- 
ing in this coastal population of C. asper, but 
indicates that this spawning is successful. By 
extrapolation, the success of intertidal spawning 
in other coastal streams of the Pacific coast, 
where catadromous populations of C. asper have 
been reported, is indicated. 
The lack of a seaward migration in "inland” 
populations with or without immediate access 
to the sea is also documented. In these popula- 
tions, fresh-water spawning is the invariable 
norm. 
Krejsa (1965) has discussed the evidence for 
recognizing a genetic distinction between 
"coastal” and "inland” populations of prickly 
sculpins based on morphology (prickling pat- 
terns) and geographic distribution. Bohn and 
Hoar (1965) have presented physiological evi- 
dence based on a comparison of iodine metab- 
olism in "coastal” (Little Campbell River) and 
"inland” (Lagace Creek, Hatzic Lake) forms 
of C. asper. They concluded that the two popu- 
lations studied have diverged genetically in their 
physiological capacities to deal with water of 
different electrolyte content. 
If the above evidence is considered in light 
of the present study, the following picture 
emerges. Weakly -prickled C. asper living in 
coastal streams having open access to the sea 
undertake a downstream migration to the estu- 
arine regions where eggs are spawned, hatched, 
and the young are reared successfully. Densely- 
prickled C. asper living in distant inland streams, 
where access to the sea is almost impossible, 
undertake only local migratory movements. But 
densely-prickled forms living in some inland 
