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Fishery Bulletin 103(1) 



downwelling, high wind stress, eddies, and storm activ- 

 ity, resulting in a high degree of mixing. The rapid rise 

 and early peak recorded in quillback rockfish otoliths, 

 followed by a postbomb decline, indicated rapid ocean- 

 atmosphere gas exchange in the shelf waters off south- 

 east Alaska. Shallow continental shelf waters, such as 

 the environment inhabited by juvenile quillback rock- 

 fish, have a thin mixed layer and relatively long surface 

 residence time, resulting in a relatively fast response 

 and build up of bomb- 14 C from the atmospheric signal. 

 In addition, low prebomb 14 C values in the quillback 

 rockfish record may indicate the influence of upwelled 

 14 C-depleted waters on southeast Alaskan coastal sur- 

 face waters. This is expected because surface waters 

 sampled off the Alaskan Peninsula (GEOSECS; Ostlund 

 and Stuvier, 1980) in 1973 had low 14 C values (+62%c) in 

 relation to the subtropical Pacific (Oahu coral, +174. 5%r 

 in 1973, Toggweiler et al., 1991), indicating the influence 

 of upwelled 14 C-depleted waters. 



A comparison of the 14 C time series determined from 

 quillback rockfish otoliths to the established 14 C time se- 

 ries exhibited synchronicity with the global rise in radio- 

 carbon. The quillback rockfish record and high latitude 

 northern hemisphere records from Arcto-Norwegian cod 

 and haddock exhibited nearly identical years of initial 

 rise and rates of 14 C increase. Note that there are differ- 

 ences among these records in the prebomb and peak 14 C 

 levels attained and the behavior of bomb- 14 C after the 

 peak, but it is irrelevant to the utility of the technique 

 as an age validation tool. The quillback rockfish record 



was also temporally similar to a Hawaiian Island corals 

 record (Oahu, Toggweiler et al., 1991; Hawaii, Druffel et 

 al., 2001), both increasing rapidly from the late 1950s. 

 However, as expected, the corals had higher prebomb 

 levels (-50%o cf. -90%o), a later peak (1971 cf. 1967) at 

 a higher value (YlA%c cf. 105%c), and the indication of 

 a more rapid decline in the postbomb years. These dif- 

 ferences are indicative of the different oceanographic 

 influences on the subtropical waters (e.g., lesser relative 

 influence of upwelled, 14 C-depleted, deep water). 



Possible sources of error in the quillback rockfish 14 C 

 record are the specific location of each fish during its 

 first year of growth, possible inaccuracies in the method 

 of extracting the core, age estimate uncertainty, and 

 variable oceanographic conditions during the year of 

 otolith formation. The unknown geographic location of 

 individual fish during the first year of life is a potential 

 source of 14 C variation. Although juvenile quillback 

 rockfish occupy relatively limited regions, factors such 

 as local bathymetry, coastal upwelling, and freshwater 

 input are likely to impact the 14 C content of the lo- 

 cal waters. Two of the quillback otolith samples (birth 

 years 1967 and 1980) had considerably higher (~50%o) 

 14 C values when compared to the highest yelloweye 

 rockfish value for that same year. These elevated 14 C 

 values may indicate that the individuals resided in 

 different water masses. The variability of otolith 14 C 

 values from regional effects is evident in the observed 

 ±11.5%o (1 SD) associated with prebomb values, a higher 

 variability than expected from the analytical uncertain- 



