like the ratio for spawning males (3:1). The 

 results of my analysis of albumin and globulin 

 are consistent with those of Robertson, Krupp, 

 Favour, Hane, and Thomas (1961), who found 

 that the normal ratio of albumin to globulin of 

 1 :2 in chinook salmon living in the sea was 

 reversed in both sexes during migration but 

 tended to revert to the original during spawn- 

 ing. 



The greater reduction of albumin and glo- 

 bulin in females than in males by spawning 

 time probably indicates a greater depletion of 

 body protein in egg formation. Shell (1961), 

 who surveyed the nutritive, osmotic, and other 

 functions of blood proteins in fish, found a cyclic 

 reversal of the albumin-globulin ratio in small- 

 mouth bass, Micropterus dolomieui, and in his 

 review of the literature stated that "Results of 

 determinations of the A:G ratio in fish are 

 confusing." 



GLUCOSE 



My discussion of glucose levels includes com- 

 parisons between pink salmon in the migrat- 

 ing and the prespawning stages and between 



20 40 60 80 



GLUCOSE (MILLIGRAMS PERCENIl 



100 



Figure 4. — Glucose of blood of adult pink salmon in 

 three stages of maturity. (C, sexes combined; F, 

 females; M, males; single asterisk, early run; double 

 asterisk, late run.) 



pink salmon in early and late runs (fig. 4 

 and table 2) . The drop in glucose between the 

 migrating and prespawning fish is significant 

 at the 1-percent level, and the decrease from 

 early to late spawners is significant at the 2.5- 



percent level. The different levels of glucose in 

 spawning salmon may be attributed to the fact 

 that the salmon of the early run at Olsen 

 Creek were not completely ready to spawn, 

 whereas the fish of the late run were actually 

 spawning. The findings are in accord with 

 those of Lysaya (1951). 



It is commonly assumed that carbohydrate 

 metabolism in fish is inefficient. Robertson and 

 Wexler (1960), however, found an increase in 

 the number and size of islets of Langerhans 

 in chinook salmon during the spawning mi- 

 gration. Robertson, Krupp, Favour, Hane, and 

 Thomas (1961) found an increase in blood 

 glucose while fish were migrating from the 

 open sea, followed by a tendency toward a 

 decrease during spawning. They suggested that 

 rising levels of blood glucose are due to glu- 

 coneogenesis that results from the action of 

 increasing adrenal corticoids on muscle and 

 fat deposits and a simultaneous increase in 

 insulin production to utilize the product. 



This viewpoint is somewhat corroborated 

 by studies on the Fraser River in which sock- 

 eye salmon have shown an 11- to 30-percent 

 loss of body flesh (Idler and Tsuyuki, 1958) 

 accompanying increased production of adrenal 

 corticosteroid hormones (Idler et al., 1959). 

 Chang and Idler (1960) observed that liver 

 glycogen gradually decreased during migration 

 in fresh water but increased at spawning. 

 These changing glycogen levels were attributed 

 to changing hormone balances. 



CHOLESTEROL 



Cholesterol levels are compared among the 

 three stages of maturity (fig 5). A downward 

 trend in cholesterol levels from the migrating 

 to the spawning stage was consistent, i.e. sig- 

 nificantly lower (at the 1-percent level) in the 

 prespawning than the migrating fish and in the 

 spawning than the prespawning fish. Robert- 

 son, Krupp, Favour, Hane, and Thomas (1961) 

 and Idler and Tsuyuki (1958) observed this 

 same consistent downward trend in chinook 

 salmon. Although I found this downward trend 

 in cholesterol levels from the migrating to the 

 spawning stage, levels in pink salmon within 

 the spawning group were higher in the late 

 run than in the early run. 



BLOOD OF ADULT PINK SALMON 



199 



