primarily of Pacific herring and bay goby. 

 They comprised 88% of the larvae collected 

 in station 4 and 89% in station 5. On the other 

 hand, the two least productive stations, 2 

 and 3, were located near the mouth of the 

 Bay and they differed from stations 1, 4, and 

 5 in that they had no eelgrass or mudflats 

 in close proximity. In addition, the water 

 currents were visually noted to be the great- 

 est in stations 2 and 3. 



Although station 5 had the second highest 

 catch rate, it exhibited the lowest number 

 of species (Fig. 6). This may be linked to the 

 comparatively wide range in temperature 

 and salinity found in station 5. The Pacific 

 herring, northern anchovy, longfin smelt, an 

 unknown smelt, bay goby, arrow goby, and 

 the Pacific staghorn sculpin were most ubiqui- 

 tous during the course of the study. Whereas 

 offshore species, bothids, and plueronectids 

 were largely confined to the stations nearest 

 the Bay entrance, resident demersal groups 

 (cottids and gobiids) were concentrated in 

 Areata Bay. 



3 4 



SAMPLING STATIONS 



Figure 6. — The number of species of fish larvae and 

 juveniles collected in each station during 1969. 



Seasonal Distribution 



Two periods of abundance are evident in 

 the seasonal distribution of the average month- 

 ly larval fish catch per cubic meter (Fig. 7). 

 The peak in January and February is primari- 

 ly due to Pacific herring, and the high in 

 April and May is a result of large bay goby 

 catches. A slight increase in catch was noted 

 in October because of an increase in the num- 

 ber of arrow gobies; however, fish larvae 

 were comparatively scarce after June. The 



" *-WmmlM 



JAN FIB MAI API MAT JUN JUl AUO SIP OCT NOV OIC 



Figure 7. — The mean fish catch per cubic meter of 

 water sampled each month during 1969. 







.-. . . ■ ■ ■ ■ , ■ i ■ ■■ ■ — - 



AUG ' SIP ' OCT ' NOV ' DEC 



Figure 8. — The number of species of fish larvae and 

 juveniles captured each month during 1969. 



period from January to May yielded the high- 

 est average number of species caught (Fig. 

 8). They consisted primarily of resident in- 

 shore species, Sebastes spp., hexagrammids, 

 cottids, and the Pacific sand lance. The longfin 

 smelt was collected throughout the year with 

 the largest numbers in January. Interestingly, 

 the December catch exhibited a marked in- 

 crease in the number of species while the 

 catch remained low. This was the effect of 

 an influx of larvae spawned offshore. The 

 Northern anchovy was collected sporadically 

 during four different times of the year. 



DISCUSSION 



The ichthyoplankton population of Humboldt 

 Bay appears to follow a pattern in which the 

 majority of species are endemic to the immedi- 

 ate area. In this survey 32 of the 37 collected 



