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Mean difference between age estimates generated from anal (A) fin, (D) dorsal fin, (P1) pectoral fin, and (P2) pelvic fin rays, and (S) scales of Blue Sucker, and the age estimated from the lapillar otolith of that individual by experienced (n = 5) and novice (n = 4) readers. Error bars represent one standard deviation. 

Mean difference between age estimates generated from anal (A) fin, (D) dorsal fin, (P1) pectoral fin, and (P2) pelvic fin rays, and (S) scales of Blue Sucker, and the age estimated from the lapillar otolith of that individual by experienced (n = 5) and novice (n = 4) readers. Error bars represent one standard deviation. 

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Evaluating the precision of age estimates generated by different readers and different calcified structures is an important part of generating reliable estimations of growth, recruitment, and mortality for fish populations. Understanding the potential loss of precision associated with using structures harvested without sacrificing individuals, such...

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... difference between the age estimated for the same individual from its otolith and that from other aging structures was influenced by the structure used to gen- erate the age estimate (Table 2, Fig. 2) and tended to increase with TL. The skill level of the reader did not have a detectable effect. Anal, dorsal, and pelvic fin rays underestimated the age compared to otoliths (Table 3; the least-square mean differ- ences were all less than zero (t 441 ≤ -2.37, P ≤ 0.02; Fig. 2). However, age estimates from pectoral fin rays (t 441 = -1.62, P = 0.11) and scales (t 441 = -0.95, P = 0.75) did not exhibit any bias relative to ...
Context 2
... difference between the age estimated for the same individual from its otolith and that from other aging structures was influenced by the structure used to gen- erate the age estimate (Table 2, Fig. 2) and tended to increase with TL. The skill level of the reader did not have a detectable effect. Anal, dorsal, and pelvic fin rays underestimated the age compared to otoliths (Table 3; the least-square mean differ- ences were all less than zero (t 441 ≤ -2.37, P ≤ 0.02; Fig. 2). However, age estimates from pectoral fin rays (t 441 = -1.62, P = 0.11) and scales (t 441 = -0.95, P = 0.75) did not exhibit any bias relative to ...
Context 3
... difference between the age estimated for the same individual from its otolith and that from other aging structures was influenced by the structure used to gen- erate the age estimate (Table 2, Fig. 2) and tended to increase with TL. The skill level of the reader did not have a detectable effect. Anal, dorsal, and pelvic fin rays underestimated the age compared to otoliths (Table 3; the least-square mean differ- ences were all less than zero (t 441 ≤ -2.37, P ≤ 0.02; Fig. 2). However, age estimates from pectoral fin rays (t 441 = ...
Context 4
... by the structure used to gen- erate the age estimate (Table 2, Fig. 2) and tended to increase with TL. The skill level of the reader did not have a detectable effect. Anal, dorsal, and pelvic fin rays underestimated the age compared to otoliths (Table 3; the least-square mean differ- ences were all less than zero (t 441 ≤ -2.37, P ≤ 0.02; Fig. 2). However, age estimates from pectoral fin rays (t 441 = -1.62, P = 0.11) and scales (t 441 = -0.95, P = 0.75) did not exhibit any bias relative to ...

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... However, accurate estimates of age and growth are imperative in understanding the reasons behind differences in PSD values. Comparable estimates of growth may not currently be available for Blue Suckers because fish have MANAGEMENT BRIEF 203 traditionally been aged using pectoral fin rays (Bednarski and Scarnecchia 2006;LaBay et al. 2011;Acre et al. 2017), but recent studies comparing the use of fin rays versus otoliths to age Blue Suckers have demonstrated that ages that are assigned using otoliths tend to be higher in larger individuals (Carlson et al. 2021;Radford et al. 2021). Although ages that are assigned by using otoliths and fin rays have not been validated for Blue Suckers, validations that have been performed for other species have demonstrated that otoliths provide more accurate age estimates (Buckmeier et al. 2002;Buckmeier and Howells 2003;Lackmann et al. 2019). ...
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... LaBay et al. (2011) reported that, relative to fin rays, scales were less precise and underestimated the ages of individuals >7 years old. Acre et al. (2017) compared Blue Sucker age estimates from scales, anal fin rays, dorsal fin rays, pelvic fin rays, pectoral fin rays, and lapillus otoliths. They did not identify any bias between the ages obtained from scales or pectoral fin rays relative to otoliths. ...
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