sustained periods of southward wind in 1971. 

 There were only four "upwelling events": 2-10 

 May, 16-25 May, 20 June-2 July, and 10-24 July. 

 Each of these events was unusual compared to 

 those of other years in that the wind also had a 

 substantial eastward component. There were also 

 four storms from the southwest of the sort that 

 characterize the winter period on the Oregon 

 coast: 11-15 May, 16-23 June, 7-9 July, and 27-31 

 August. It is expected that under these conditions 

 surface waters from offshore would have been 

 more prevalent in the nearshore zone in 1971 than 

 in other years. The composition of the plankton 

 observed in 1971 within 18 km from shore is in 

 agreement with that hypothesis. 



Comparison of onshore-offshore hydrographic 

 sections for upwelling events and for intervals of 

 low southward winds (Smith 1974) suggests an 

 explanation for the fact that NH 10 does not show 

 the same degree of year-to-year variations as sta- 

 tions nearer shore. During the upwelling season all 

 isopycnals below 15 m slope upward toward the 

 shore at least as far seaward as 30 km. Upward 

 sloping extends to the shore during upwelling 

 events, but during lapses of the southward wind 

 the isopycnals come to slope downward toward 

 shore from 10 km seaward to the beach. Seaward 

 of 10 km they continue to slope upward despite 

 prolonged lapses. It seems likely that coastal up- 

 welling only takes the form of pulsed events in this 

 most inshore zone. Thus it is reasonable that the 

 low frequency and amplitude of upwelling events 

 in 1971 only had a pronounced effect on the 

 planktology at stations less than 10 km from shore. 

 On the other hand, Hubbard and Pearcy (1971) 

 demonstrated marked changes in the species 

 composition of the salp fauna off Oregon at dis- 

 tances beyond 28 km from shore in 1963, another 

 year of anomalously low coastal upwelling (Bakun 

 1973). The detailed relationship between inshore 

 and offshore plankton changes as correlated with 

 year-to-year weather variations cannot yet be 

 deduced. The length, frequency, and spatial extent 

 of the data set necessary to deal with this problem 

 probably puts it beyond our reach. 



There is a suggestion in the data that intense 

 upwelling events rather immediately result in 

 high zooplankton abundance at the NH 1 and NH 3 

 stations. Huge population peaks on 10, 18, and 25 

 July 1969 and 23 June and 2 July 1970 were as- 

 sociated with periods of intense upwelling. The 

 high density found on 22 June 1969, however. 



followed a 41-day period of little or no north wind. 

 It seems most likely that peak densities are simply 

 reached at about the same time each year, namely 

 late June and early July. We do not as yet know the 

 relationship between copepod developmental 

 schedules and the seasons in this area well enough 

 to decide this issue with any certainty. Further 

 analysis of our data as it bears on this point is 

 planned. 



Summers of below average upwelling like 1971, 

 together with the resultant reductions in primary 

 and secondary production, probably have impor- 

 tant effects upon nearshore fisheries. A statistical 

 link exists between summer upwelling strength 

 and Dungeness crab production (Peterson, 1973). 

 A strong upwelling season results in a heavy crab 

 catch iy2 yr later. The Dungeness crab catch for 

 the 1972-1973 season was one of the lowest on 

 record. 



Other fisheries seem to have been similarly af- 

 fected. The Fish Commission of Oregon has 

 documented 1971 as a poor growth year for the 

 shrimp Pandalus jordani (Robert L. Demory, 

 Oregon Fish Commission, Newport, Ore., pers. 

 commun.), coho salmon, Oncorynchus kisutch 

 (Paul H. Reed, Oregon Fish Commission, Newport, 

 Ore., pers. commun.), and razor clams Siliqua pa- 

 tula (C. Dale Snow, Oregon Fish Commission, 

 Newport, Ore., pers. commun.). The shrimp data 

 are mean carapace length of Age I animals from 

 the Coos Bay, Ore. area (lat. 43°15'N) and are as 

 follows: 1969, 16.45 cm; 1970, 16.76 cm; and 1971, 

 15.87 cm. Averaged dressed weights of coho salm- 

 on were 2.59 kg in 1969, 3.41 kg in 1970, and 2.68 

 kg in 1971. Razor clam lengths averaged 75.4 mm 

 in 1969, (no data for 1970), 69.4 mm in 1971, 78.5 

 mm in 1972, and 83.5 mm in 1973. Some of these 

 data may be better interpreted in terms of good 

 growth years. As shown by the wind data (Figure 

 3), 1970 had many more days of upwelling inducing 

 winds than 1969. Primary and secondary produc- 

 tion should have been greater in 1970. Both shrimp 

 and coho salmon were larger in 1970. Unfortu- 

 nately no razor clam data were taken in 1970, but 

 data for other years support the conclusion that 

 1971 was a poor growth year. 



ACKNOWLEDGME NTS 



The sampling program for this study was start- 

 ed by Jefferson J. Conor and William G. Pearcy 

 who graciously allowed us to participate. R. 

 Gregory Lough, Peter Rothlisberg, and others 



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