@article {2682, title = {Growth and longevity of Hawaiian grouper (Hyporthodus quernus) {\textemdash} input for management and conservation of a large, slow-growing grouper}, journal = {Canadian Journal of Fisheries and Aquatic Sciences}, volume = {76}, year = {2019}, month = {Jan-10-2019}, pages = {1874 - 1884}, abstract = {Hawaiian grouper (Hyporthodus quernus) is endemic to the Hawaiian Islands and is regionally important, yet little is known about its life history. This large species is managed within the Deep 7 bottom fish complex, which includes six snapper species that are assumed to have similar life history traits. Previous age estimates were not validated and suggested a maximum age of 34 years. To evaluate the preliminary study and provide a valid basis for life history parameters, we aged otoliths using bomb radiocarbon (14C) dating. Measured 14C values provided ages for smallest to largest fish that differed from the original study. The fundamental information provided here when evaluating Hawaiian grouper conservation status is longevity (valid to 50 years and estimated to 76 years) {\textemdash} no male sampled was <80 cm total length (TL) and younger than 34 years {\textemdash} and age-at-sexual maturity and age-at-sex change, which were indirectly estimated and compared with prior published estimates for this and other groupers. Updated life history parameters (k = 0.078, L$\infty$ = 95.8 cm TL) should be used to improve future management and conservation assessments.}, issn = {0706-652X}, doi = {10.1139/cjfas-2018-0170}, url = {https://www.nrcresearchpress.com/doi/full/10.1139/cjfas-2018-0170}, author = {Andrews, Allen H. and DeMartini, Edward E. and Brodziak, Jon and Nichols, Ryan S. and Humphreys, Robert L.} } @article {2633, title = {Blue marlin ( Makaira nigricans ) longevity estimates confirmed with bomb radiocarbon dating}, journal = {Canadian Journal of Fisheries and Aquatic Sciences}, volume = {75}, year = {2018}, month = {Jan-01-2018}, pages = {17 - 25}, abstract = {The longevity of blue marlin (Makaira nigricans) remains unresolved. The use of fin spines and sagittal otoliths for age reading has led to unconfirmed longevity estimates near 20-30 years. Age validation has been elusive because large individuals are uncommonly caught, and a technique that can be applied to structures that provide estimates of age was absent. The use of otolith chemical signatures has been limited by sagittal otoliths that are very small-whole otolith mass of adult blue marlin rarely exceeds 10 mg for the largest fish. Recent advances in the detection limits of radiocarbon (14C) with accelerator mass spectrometry-coupled with recently acquired knowledge of marine bomb 14C signals spanning the tropical Pacific Ocean-have led to an opportunity to age blue marlin from small amounts of otolith material. In this study, otoliths from a recently collected 1245 lb (565 kg) female blue marlin at a measured 146-inch (371 cm) lower jaw fork length were analyzed for 14C. Estimated longevity was either 12-21 or 32-44 years on the basis of bomb 14C dating. Using multiple lines of evidence, it was determined that the young age scenario was most likely, with evidence for an age close to 20 years using a series of deductions in the bomb 14C dating method.}, keywords = {Accelerator mass spectrometry, Biology, Blue marlin, Ecology, Fish measurement, FisheryLongevity, Otolith, Radiocarbon dating}, issn = {0706-652X}, doi = {10.1139/cjfas-2017-0031}, url = {http://www.nrcresearchpress.com/doi/10.1139/cjfas-2017-0031http://www.nrcresearchpress.com/doi/pdf/10.1139/cjfas-2017-0031http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjfas-2017-0031}, author = {Andrews, Allen H. and Humphreys, Robert L. and Sampaga, Jeffery D.} } @article {2576, title = {Age and growth of bluespine unicornfish (Naso unicornis): a half-century life-span for a keystone browser, with a novel approach to bomb radiocarbon dating in the Hawaiian Islands}, journal = {Canadian Journal of Fisheries and Aquatic Sciences}, volume = {73}, year = {2016}, month = {Jan-10-2016}, pages = {1575 - 1586}, abstract = {Bluespine unicornfish (Naso unicornis) from Hawaii were aged to >50 years using cross-sectioned sagittal otoliths. Fish length was a poor indicator of age because of rapid and variable early growth, exemplified by fish aged to be 4 years near maximum length. Growth was deterministic with adult ages decoupled from body length. Otolith mass and thickness were evaluated as proxies for age and both were encouraging; thickness explained more variance but mass was easier to measure. An age estimation protocol was validated through ontogeny using bomb radiocarbon (14C) dating. Use of the postbomb 14C decline period from a regional reference chronology enabled age validation of young fish {\textemdash} a novel approach for the Pacific Ocean. A probabilistic procedure for assigning bomb 14C dates (CALIBomb) was used for the first time to determine fish birth years. The age-reading protocol was generally validated, and it was possible to describe length-at-age despite difficulties in counting otolith annuli beyond 30{\textendash}40 years. Growth curves differed between the sexes, and a four-parameter generalized von Bertalanffy growth function provided the best fit.}, issn = {0706-652X}, doi = {10.1139/cjfas-2016-0019}, url = {http://www.nrcresearchpress.com/doi/10.1139/cjfas-2016-0019}, author = {Andrews, A.H. and DeMartini, Edward E. and Eble, Jeff A. and Taylor, Brett M. and Lou, Dong Chun and Humphreys, Robert L.} }