Article
Biodiversity Conservation
Colin P. Gallagher, Rick J. Wastle, Julie R. Marentette, Louise Chavarie, Kimberly L. Howland
Summary: This study assessed precision and bias in age estimations for lake trout using different readers with varying levels of experience. It found that sectioned otoliths provided more precise age estimations compared to whole otoliths and fin-ray sections. Increased reader confidence was associated with higher precision and younger age estimates, particularly for whole otoliths.
Article
Environmental Sciences
Brenden D. Slongo, Lauren D. Hayhurst, Paul C. T. Drombolis, Chris D. Metcalfe, Michael D. Rennie
Summary: This study evaluated the impacts of chronic exposures to nanosilver on Northern Pike, and found that prolonged exposure to nanosilver can result in reduced growth rate and prey availability for Northern Pike, with potential long-term effects even after the cessation of nanosilver additions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Dusan Nikolic, Stefan Skoric, Sasa Jankovic, Aleksandar Hegedis, Vesna Djikanovic
Summary: The study found that young northern pike individuals were more sensitive to pollution, but older fish showed higher overall bioaccumulation of toxic elements. Since there was no significant correlation between metal accumulation and fish condition, the relationship between age and accumulation of toxic elements was also insignificant.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2021)
Article
Environmental Sciences
Yao Guo, Yongnan Rao, Xue Wang, Decai Zou, Huihui Shi, Ning Ji
Summary: A distinctive feature of modern Global Navigation Satellite System (GNSS) signals is that they transmit multiple signal components at the same carrier frequencies. The National Timing Center of the Chinese Academy of Sciences has built a space signal-quality monitoring and evaluation system based on a 40 m dish antenna, which can achieve high-fidelity reception of navigation signals and fine signal quality monitoring of GNSS satellites. Based on this platform, a method to estimate the carrier characteristic bias between GNSS signals is proposed. The measured data shows that the carrier phase bias correction improves the joint positioning accuracy of GNSS signals.
Review
Biology
Louis-Stephane Le Clercq, Antoinette Kotze, J. Paul Grobler, Desire Lee Dalton
Summary: Various biological attributes associated with individual fitness in animals change over the lifespan, which often requires the need for age determination methods in animal ecology and conservation work. Current methods for determining age have limitations and lack standardization. Biological clocks, such as tooth layer annulation and otolith layering, have been explored as potential universal age determination methods. Recently, methylation and telomere length have been adapted from human studies to study animal aging. Both methods have been studied across multiple vertebrate classes and show promise in accurately determining age in animals. Methylation outperforms telomere length in terms of predictive power and smaller prediction intervals.
BIOLOGICAL REVIEWS
(2023)
Article
Biology
Qiaowei Pan, Romain Feron, Elodie Jouanno, Hugo Darras, Amaury Herpin, Ben Koop, Eric Rondeau, Frederick W. Goetz, Wesley A. Larson, Louis Bernatchez, Mike Tringali, Stephen S. Curran, Eric Saillant, Gael P. J. Denys, Frank A. von Hippel, Songlin Chen, J. Andres Lopez, Hugo Verreycken, Konrad Ocalewicz, Rene Guyomard, Camille Eche, Jerome Lluch, Celine Roques, Hongxia Hu, Roger Tabor, Patrick DeHaan, Krista M. Nichols, Laurent Journot, Hugues Parrinello, Christophe Klopp, Elena A. Interesova, Vladimir Trifonov, Manfred Schartl, John Postlethwait, Yann Guiguen
Summary: This study traced the evolution of sex determination in an entire teleost order through following the fate of a master sex-determining gene in northern pike, revealing that the gene originated from a gene duplication event 65 to 90 million years ago and remained sex linked on undifferentiated sex chromosomes for at least 56 million years in multiple species. Various independent species- or population-specific sex determination transitions, including the recent loss of a Y chromosome, were identified. Occasional sex reversals and genetic bottlenecks were proposed as non-adaptive explanations for sex determination transitions.
Article
Multidisciplinary Sciences
Benjamin Mayne, Tom Espinoza, David A. Crook, Chloe Anderson, Darren Korbie, Jonathan C. Marshall, Mark J. Kennard, Doug J. Harding, Gavin L. Butler, Brien Roberts, Josh Whiley, Sharon Marshall
Summary: Age structure information is crucial for the conservation and management of animal populations. This study demonstrates the use of DNA methylation as a non-lethal method to estimate the age of golden perch. The correlation between otolith age and epigenetic age was high across all clocks, with median absolute errors ranging from 2.4 to 184.6 days. This highlights the emerging utility of epigenetic clocks in supporting fish population and fisheries management.
SCIENTIFIC REPORTS
(2023)
Article
Ecology
Endre Moen, Rune Vabo, Szymon Smolinski, Come Denechaud, Nils Olav Handegard, Ketil Malde
Summary: This study developed a machine learning framework for fish age prediction using images of otoliths. The models based on convolutional neural networks achieved an average accuracy of 72.7% and performed well in predicting the age of one- and two-year-old individuals. The best models were EfficientNet B4 and EfficientNet B6 using images taken with low exposure times.
ECOLOGICAL INFORMATICS
(2023)
Article
Food Science & Technology
Alexander G. G. Dvoretsky, Fatima A. A. Bichkaeva, Olga S. S. Vlasova, Sergei V. V. Andronov, Vladimir G. G. Dvoretsky
Summary: We analyzed the fatty acid composition of northern pike muscles from Gyda River in Siberia, Russia using gas-liquid chromatography. Out of the 43 identified fatty acids, 23 accounted for 99.3% of the total content. The fatty acid profile differed from other pike populations, possibly due to diet variations. Pike flesh had desirable nutritional qualities with a low n-6/n-3 ratio, low atherogenic and thrombogenic indices, and a high ratio of hypocholesterolemic to hypercholesterolemic fatty acids, making it a suitable replacement for traditional fish sources.
Article
Public, Environmental & Occupational Health
James A. Hanley
Summary: Life expectancy is an important indicator for assessing the strengths and weaknesses of a country's health and social systems. This article presents a new intuitive method for calculating the standard error based on actual data, and extends the use of the jackknife method for analyzing event rates. The article also examines the relationship between the magnitude of the standard error and the number of person-years and deaths, and recommends using these standard errors to report the uncertainty of life expectancy numbers.
AMERICAN JOURNAL OF PUBLIC HEALTH
(2022)
Article
Fisheries
Timo D. Rittweg, Clive Trueman, Elias Ehrlich, Michael Wiedenbeck, Robert Arlinghaus
Summary: Accurate age estimates are crucial for assessing fish life histories and providing management advice. This study validated age estimates for northern pike using oxygen isotopes and found that estimates from scales significantly underestimated the age of older fish. This underestimation has implications for population models and management regulations, leading to conservative management and lost yield.
FISHERIES MANAGEMENT AND ECOLOGY
(2023)
Article
Fisheries
Yuchen Jiang, Jiamin Guo, Ayelhan Haisa, Yubang Shen
Summary: This study investigates the heat tolerance of the northern pike and its genetic basis. GWAS analysis identifies significant SNP loci and candidate genes associated with heat tolerance in the northern pike. The findings provide important insights for the cultivation of heat-resistant fry.
Article
Fisheries
John F. Bieber, Luc LaRochelle, Steven J. Cooke, Cory D. Suski, Michael J. Louison
Summary: This study evaluates the post-release locomotor activity of Northern Pike after ice angling and finds that air exposure time does not affect their movement. However, there may still be unmeasured long-term stress. Therefore, it is recommended for anglers to minimize air exposure to reduce the potential for sublethal impairments or mortality.
FISHERIES RESEARCH
(2022)
Article
Environmental Sciences
Jason T. T. Magnuson, Mark B. B. Sandheinrich
Summary: This study examined the relationship between selenium (Se), methylmercury (MeHg), inorganic mercury (IHg), total mercury (THg), and the expression of biomarkers of oxidative stress and metal regulation in northern pike livers. The results showed a positive correlation between THg and Se concentrations, with a mercury:selenium molar ratio less than one. There was no significant relationship between biomarker expression and mercury:selenium molar ratios, except for catalase and superoxide dismutase, which were significantly related to the increase in MeHg concentration relative to THg.
Article
Fisheries
Josipa Ferri, Andela Brzica
Summary: Age and growth of the European barracuda in the eastern Adriatic Sea were studied using otoliths. Counting otolith annuli provided a more accurate estimation of age than linear models based on otolith morphometrics.