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114 16 - E E14 .......... ....J I- .!: ~ 12 co ::J [10 o "0 co ~ o 8 o () BESTGEN AND BUNDY A Control --+- 5d -A- 10d -e-- 15d -A- 17,5d -e- 6 o 10 20 30 Days posthatch 40 B 300 Control --+- - ::t 250 5d -A- 10d -e-- .......... ~ Q) +-' Q) ~ 200 "0 Cf) ::J 15 d -A- 17,5d -e- g. 150 ....J 100 o 10 20 30 Days post hatch 40 FIGURE 5,-(A) Somatic (total length, TL) and (B) otolith (diameter, ILm) growth patterns of 6-d-old Colorado squawfish larvae subjected to starvation periods of 5,10, 15, or 17,5 d and then allowed to resume feeding, Error bars about means are ::':2 SE (N = 5); temperature was a constant 210C. pana 1990), similar intercepts would be expected for larvae hatched under the same pretreatment conditions. The differing intercepts in Figures 2 and 3 probably are artifacts of slope differences. Nonproportional somatic and otolith growth was also confirmed in experiment 2, when somatic growth nearly ceased but otolith growth continued during a 6-d starvation period. The zone in the otolith represented by the starvation period was accurately identified, even though increments were slightly less clear there, because the number of clear daily increments counted before and after starvation matched expectations. Measurements of otolith zones representing periods before, during, and after starvation were within 5.1 % for two read- ers, indicating minimal bias from measurement er- ror or zone interpretation. Nonproportional growth also was evident when 6-d-old Colorado squawfish larvae that were just beginning to feed were subjected to varied star- vation periods. Somatic growth abated little during 5-d starvation, probably because residual yolk sus- tained fish for at least part of that interval; nev- ertheless, an unexpected decline in growth (of both body and otolith) occurred later, when fish were feeding. During longer (10-17.5-d) starvation pe- riods, otoliths continued to grow, albeit slowly, after somatic growth ceased. As in this study, oth- ers (Eckmann and Rey 1987; Maillet and Checkley 1990; Bradford and Geen 1992) have found that normal otolith growth is delayed for several days after starvation ends and feeding resumes. We also saw delayed resumption of somatic growth after lO-d and longer starvation periods. A delay period may be necessary to rebuild metabolic reserves and restore basic physiological processes before otolith and somatic growth can resume. Otoliths of larvae starved 10 or more days showed distinct zones representing the starvation period. The first seven to nine increments, which were obvious in most otoliths, were probably pro- duced when fish subsisted on yolk. Increments were typically very faint or not present after 10 d in starved fish, but were obvious within I to 2 d after feeding began. Thus, effects of starvation de- pended on duration of the period without food and were manifest as absence of otolith increments, lack of otolith growth, or both. Opaque zones in otoliths of wild fish may indicate periods of low food abundance.