Abstract
AbstractStudies to determine precision and bias of both methods and age-readers are important to evaluate reliability of age data used for developing fisheries management objectives. We assessed within-reader, between-reader, and between-method precision (coefficient of variation, CV%) and bias of age estimations for long-lived lake trout, Salvelinus namaycush, from Great Bear Lake using three readers with different levels of experience. The assessment used independent age estimates (n = 3 per reader) from whole and transverse-sectioned otoliths (range = 1–67 years), and pelvic fin-ray sections (range = 3–26 years). We also examined between-method differences in assigned confidence scores. Within readers, age estimates from sectioned otoliths were more precise (2.6–3.0%) than whole (3.6–4.5%) otoliths. Between whole and sectioned otoliths, precision of age estimates was 5.4% and bias was low up to age 20. Age was typically under-estimated from whole otoliths compared to sections for fish ≥ 34 years. Increased reader confidence was correlated with greater precision and younger age estimates, particularly for whole otoliths, but less so for fin rays. Age was estimated with higher confidence from otolith sections than other methods. The least experienced reader estimated age with the lowest precision, and between-reader bias was evident among older ages. Age was consistently under-estimated and less precise from pelvic fins compared to sectioned otoliths, and are therefore an unsuitable non-lethal alternative. Sectioned otoliths revealed longevity was greater (67 years) than historically documented using whole otoliths (53 years) for these fish. Our findings contribute to those relying on otoliths or pelvic fin rays to estimate ages of long-lived lake trout populations, which are a key component of freshwater fauna in polar North America.
Funder
Fisheries and Oceans Canada
Sahtu Renewable Resources Board
NWT Cumulative Impact Monitoring Program
Natural Resources Canada Polar Continental Shelf Program
Publisher
Springer Science and Business Media LLC
Subject
General Agricultural and Biological Sciences
Reference67 articles.
1. Andrews AH, Burton EJ, Kerr LA, Cailliet GM, Coale KH, Lundstrom CC, Brown TA (2005) Bomb radiocarbon and lead-radium disequilibria in otoliths of bocaccio rockfish (Sebastes paucispinis): a determination of age and longevity for a difficult-to-age fish. Mar Freshw Res 56:517–528. https://doi.org/10.1071/MF04224
2. Barber WE, McFarlane GA (1987) Evaluation of three techniques to age Arctic Char from Alaskan and Canadian waters. Trans Am Fish Soc 116:874–881. https://doi.org/10.1577/1548-8659(1987)116%3c874:EOTTTA%3e2.0.CO;2
3. Beamish RJ (1979) Differences in the age of Pacific hake (Merluccius productus) using whole otoliths and sections of otoliths. J Fish Res Board Can 36:141–151. https://doi.org/10.1139/f79-023
4. Buckmeier DL, Sakaris PC, Schill DJ (2017) Validation of annual and daily increments in calcified structures and verification of age estimates. In: Quist MC, Isermann DA (eds) Age and growth of fishes: principles and techniques. Am Fish Soc. Bethesda, Maryland, pp 33–79
5. Burnham-Curtis MK, Bronte CR (1996) Otoliths reveal a diverse age structure for humper lake trout in lake superior. Trans Am Fish Soc 125:844–851. https://doi.org/10.1577/1548-8659(1996)125%3c0844:ORADAS%3e2.3.CO;2
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献