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Witch Flounder: QA/QC Exercise Results

Results of the QA/QC exercises for ageing witch flounder.

Witch Flounder, Glyptocephalus cynoglossus

Image
Witch flounder illustration. Credit: Jack Hornady.

Sarah Emery (SE) has been working with Witch Flounder since 2010. Sectioned otoliths are aged with transmitted light.

In tests where agreement is below 90%, bias indicates either the P-value of a symmetry test or ‘n/s’ (test not significant at the α = 0.05 level). The Evans & Hoenig test was used to test bias starting 1/2022; prior to that, a Bowker's test was used.

Sample Source Test Type Date Com-pleted Age Reader Number Aged Number Tested CV (%) Agree-ment (%) Bias
2022 Commercial Samples (Q1-2) Precision 9/2022 SE 145 42 0.70 90.5  
2022 Spring Survey (202202) Precision 7/2022 SE 465 80 1.76 87.5 n/s
2021 Autumn Survey (202104) Precision 2/2022 SE 534 68 1.68 86.8 n/s
2021 Commercial Samples (Q1-2) Precision 1/2022 SE 189 63 1.17 85.7 n/s
2021 Spring Survey (202102) Precision 9/2021 SE 510 51 2.76 86.3 n/s
2020 Commercial Samples (Q4) Precision 5/2021 SE 177 46 0.89 89.1 n/s
2020 Commercial Samples (Q3) Precision 4/2021 SE 142 38 1.24 86.8 n/s
2020 Commercial Samples (Q2) Precision 12/2020 SE 136 45 1.27 84.4 n/s
2020 Commercial Samples (Q1) Precision 8/2020 SE 194 46 1.27 82.6 n/s
2019 Commercial Samples (Q4) Precision 4/2020 SE 182 48 1.60 85.4 n/s
2019 Commercial Samples (Q3) Precision 4/2020 SE 190 57 1.42 84.2 n/s
2019 Autumn Survey (201904) Precision 1/2020 SE 498 98 0.93 92.9  
2019 Commercial Samples (Q2) Precision 10/2019 SE 142 42 0.68 90.5  
2019 Commercial Samples (Q1) Precision 10/2019 SE 251 58 2.14 79.3 n/s
2019 Spring Survey (201902) Precision 7/2019 SE 500 97 2.55 85.6 n/s
2018 Commercial Samples (Q4) Precision 6/2019 SE 199 49 2.37 79.6 n/s
2018 Commercial Samples (Q3) Precision 3/2019 SE 217 51 1.51 82.4 n/s
2018 Autumn Survey (201804) Precision 3/2019 SE 339 75 2.38 88.0 n/s
2018 Commercial Samples (Q2) Precision 2/2019 SE 225 54 1.29 83.3 n/s
2018 Commercial Samples (Q1) Precision 9/2018 SE 247 57 1.05 87.7 n/s
2018 Spring Survey (201802) Precision 6/2018 SE 290 64 1.60 87.5 n/s
2017 Commercial Samples (Q4) Precision 5/2018 SE 195 45 1.44 84.4 n/s
2017 Commercial Samples (Q3) Precision 4/2018 SE 249 57 1.01 87.7 n/s
2017 Autumn Survey (201704) Precision 1/2018 SE 512 100 1.40 89.0 n/s
2017 Commercial Samples (Q2) Precision 12/2017 SE 256 58 0.86 89.7 n/s
2017 Commercial Samples (Q1) Precision 8/2017 SE 209 45 0.87 88.9 n/s
2017 Spring Survey (201702) Precision 7/2017 SE 387 74 1.31 89.2 n/s
2016 Commercial Samples (Q4) Precision 5/2017 SE 230 54 0.95 87.0 n/s
2016 Commercial Samples (Q3) Precision 3/2017 SE 151 40 1.55 80.0 n/s
2016 Autumn Survey (201604) Precision 1/2017 SE 515 96 1.55 88.5 n/s
2016 Commercial Samples (Q2) Precision 10/2016 SE 242 56 1.05 87.5 n/s
2016 Commercial Samples (Q1) Precision 9/2016 SE 501 97 1.24 83.5 n/s
2016 Spring Survey (201602) Precision 7/2016 SE 555 93 1.28 92.5  
2015 Commercial Samples (Q4) Precision 4/2016 SE 376 76 1.38 84.2 n/s
2015 Commercial Samples (Q3) Precision 3/2016 SE 354 74 1.42 85.1 n/s
2015 Autumn Survey (201504) Precision 2/2016 SE 562 97 1.18 93.8  
2015 Commercial Samples (Q2) Precision 11/2015 SE 481 90 1.06 88.9 n/s
2015 Commercial Samples (Q1) Precision 10/2015 SE 471 92 1.03 85.9 n/s
2015 Spring Survey (201502) Precision 7/2015 SE 635 91 1.37 93.4  
2014 Commercial Samples (Q4) Precision 6/2015 SE 312 64 1.85 82.8 n/s
2014 Commercial Samples (Q3) Precision 4/2015 SE 224 53 1.35 84.9 n/s
2014 Commercial Samples (Q2) Precision 4/2015 SE 468 91 0.94 89.0 n/s
2014 Autumn Survey (201404) Precision 2/2015 SE 479 91 0.92 93.4  
2014 Commercial Samples (Q1) Precision 1/2015 SE 641 97 0.83 88.7 n/s
2014 Spring Survey (201402) Precision 10/2014 SE 618 94 1.38 93.6  
2013 Commercial Samples (Q4) Precision 9/2014 SE 376 80 0.45 93.8  
2013 Commercial Samples (Q3) Precision 8/2014 SE 560 99 1.15 89.9 n/s
2013 Commercial Samples (Q2) Precision 8/2014 SE 518 99 0.27 97.0  
2013 Commercial Samples (Q1) Precision 6/2014 SE 399 79 0.72

91.1

 
2013 Autumn Survey (201304) Precision 6/2014 SE 381 78 1.02 92.3  
2013 Spring Survey (201302) Precision 5/2014 SE 261 58 1.65 89.7 n/s
2012 Commercial Samples (Q4) Precision 3/2014 SE 395 80 0.91 92.5  
2012 Commercial Samples (Q3) Precision 1/2014 SE 315 68 0.82 91.2  
2012 Commercial Samples (Q2) Precision 11/2013 SE 302 65 0.71 90.8  
2012 Commercial Samples (Q1) Precision 9/2013 SE 386 79 1.53 83.5 n/s
2012 Autumn Survey (201204) Precision 7/2013 SE 473 99 2.07 84.8 n/s
2012 Spring Survey (201202) Precision 2/2013 SE 453 96 1.42 88.5 n/s
2011 Commercial Samples (Q4) Precision 11/2012 SE 344 90 1.28 85.6 n/s
2011 Commercial Samples (Q3) Precision 9/2012 SE 184 50 0.95 90.0  
2011 Commercial Samples (Q2) Precision 8/2012 SE 344 98 1.47 81.6 n/s
2011 Autumn Survey (201105) Precision 6/2012 SE 470 94 1.57 88.3 n/s
2011 Commercial Samples (Q1) Precision 4/2012 SE 297 79 1.72 77.2 n/s
2010 Commercial Samples (Q1-Q4) Precision 2/2012 SE 1124 94 2.03 75.5 n/s
2009 Commercial Samples (Q1-Q4) Precision 2/2012 SE 947 100 1.44 83.0 n/s
2011 Spring Survey (201102) Precision 1/2012 SE 440 95 2.02 85.3 n/s
2008 Commercial Samples (Q3 & Q4) Precision 9/2011 SE 525 72 1.86 77.8 n/s
2008 Commercial Samples (Q2) Precision 8/2011 SE 472 96 1.59 83.3 n/s
2008 Commercial Samples (Q1) Precision 8/2011 SE 411 95 2.07 75.8 n/s
2010 Autumn Survey (201004) Precision 7/2011 SE 435 98 1.27 89.8 n/s
2010 Spring Survey (201001) Precision 6/2011 SE 581 97 2.14 84.5 n/s
2009 Autumn Survey (200904) Precision 12/2010 SE 433 100 2.64 87.0 n/s
2009 Spring Survey (200902) Precision 12/2010 SE vs. JB 698 251 1.21 89.2 n/s
2007 Commercial Samples (Q4) Precision 8/2008 JB 342 51 1.92 78.4 n/s
2007 Commercial Samples (Q3) Precision 8/2008 JB 483 50 1.60 80.0 n/s
2007 Commercial Samples (Q2) Precision 8/2008 JB 355 50 1.25 84.0 n/s
2007 Autumn Survey (200709) Precision 7/2008 JB 145 71 1.35 91.5  
2008 Spring Survey (200803) Precision 6/2008 JB 245 76 1.45 88.2 n/s
2007 Commercial Samples (Q1) Precision 11/2007 JB 529 86 1.68 77.9 n/s
2006 Commercial Samples (Q4) Precision 10/2007 JB 406 63 1.04 85.7 n/s
2006 Commercial Samples (Q3) Precision 10/2007 JB 486 59 1.43 83.1 n/s
2006 Commercial Samples (Q2) Precision 10/2007 JB 356 59 1.13 84.7 n/s
2006 Commercial Samples (Q1) Precision 10/2007 JB 438 62 1.03 83.9 n/s
2005 Commercial Samples (Q4) Precision 10/2007 JB 394 58 1.28 82.8 n/s
2005 Commercial Samples (Q3) Precision 10/2007 JB 387 52 0.96 86.5 n/s
2005 Commercial Samples (Q2) Precision 10/2007 JB 339 56 1.06 83.9 n/s
2005 Commercial Samples (Q1) Precision 10/2007 JB 231 47 0.95 87.2 n/s
2007 Spring Survey (200703) Precision 7/2007 JB 182 75 1.82 86.7 n/s
2006 Autumn Survey (200610) Precision 3/2007 JB 168 65 1.21 92.3  
2006 Spring Survey (200604) Precision 3/2007 JB 223 102 1.25 90.2  
2005 Spring Survey (200503) Calibration 2/2007 JB 76 2.08 80.3 n/s
2004 Commercial Samples (Q2 & Q4) and 2005 Spring Survey (200503) Precision 8/2005 JB 708 122 1.55 80.3 n/s

Last updated by Northeast Fisheries Science Center on December 27, 2022

Age and Growth