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31 <br />area exhibited considerable variability in size and shape. In an <br />attempt to offset this variability, measurements were taken of two <br />scales from each fish and averaged to obtain a representative growth <br />pattern. This technique did not yield a significant body length- <br />scale radius relationship. <br />Back-calculation of growth was not done for razorback suckers <br />because of the lack of a significant body length-scale radius <br />relationship. However, mean lengths and weights were calculated for <br />each age group (Table 7). All fish were collected in early spring <br />before growth began, or in late fall when growth for the year had <br />ceased. Therefore, empirical lengths should have represented the <br />size of the fish at the end of each year of life. <br />Ages were assigned to the fish based upon agreement between two <br />readers. However, the assignment of age should not be considered <br />absolute as the scale method has not yet been validated for razorback <br />suckers. Young fish were not collected, so verification of the first <br />few annuli using the length frequency method was not possible [Tesch, <br />19711. Because the razorback sucker is rare, no-fish were sacrificed <br />for otoliths, opercles or vertebrae, nor were fin rays removed for <br />age determination.' <br />Razorback suckers from California were determined to be much <br />older than those from the upper basin. A male (662 mm TL) was <br />determined to be 22 years old and another fish (length unknown) was <br />considered to be 17 years of age from analysis of otoliths {Letter <br />dated 9 December, 1976 from J. A. St. Amant, California Department <br />of Fish and Game, Long Beach]. <br />When fish become old, growth decreases and annuli are laid down