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Fishery Bulletin 92(2). 1994 



from Shelikof Strait. Eggs need to be obtained from 

 the study area and incubated at a range of tempera- 

 tures occurring in the area. Categorizing the con- 

 tinuous process of egg development into a large 

 number of stages should increase the precision of the 

 egg-age estimate 



The first objective of our study was to incubate 

 Shelikof Strait walleye pollock eggs at the mean 

 water temperature for Shelikof Strait, bracketing 

 that temperature to include upper and lower ex- 

 tremes. Egg development times were used to pro- 



duce a stage duration table and a regression model 

 to estimate egg age based on water temperature and 

 developmental stage. Morphological development is 

 described for 21 developmental stages. These de- 

 scriptions are accompanied by illustrations and 

 photographs to facilitate identification of body struc- 

 tures and stage hallmarks. 



The second objective was to compare our rates of 

 egg development to other walleye pollock incubation 

 studies. Morphological development is included in 

 this comparison. 



