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Atlantic Cod: QA/QC Exercise Results

Results of the QA/QC exercised for ageing Atlantic cod.

Atlantic Cod, Gadus morhua

Image
Left-facing illustration of yellow, olive green Atlantic cod fish with black speckles, barbel/whisker under lower jaw, and white line going across its side.

Nina Shepherd (NS) has been working with Atlantic Cod since 2003. Baked and sectioned otoliths are viewed with reflected 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. Stock indicates whether samples were from Georges Bank (GB) or the Gulf of Maine (GOM); if no stock area is specified, samples were from both areas combined. All samples were collected by the Northeast Fisheries Science Center except where indicated otherwise.

Sample Source Stock Test Type Date Completed Age Reader Number Aged Number Tested CV (%) Agree-ment (%) Bias
2023 Commercial Samples (Q3-4)   Precision 3/2024 NS 112 40 0.00 100.0  
2023 Autumn Survey (202304)   Precision 3/2024 NS 227 45 0.63 97.8  
2023 Commercial Samples (Q2)   Precision 12/2023 NS 127 40 0.00 100.0  
2023 Commercial Samples (Q1)   Precision 9/2023 NS 162 40 0.00 100.0  
2023 Spring Survey (202302)   Precision 6/2023 NS 278 51 0.00 100.0  
2022 Commercial Samples (Q1-Q4)   Precision 2/2023 NS 150 45 0.00 100.0  
2022 Autumn Survey (202204)   Precision 2/2023 NS 283 42 0.00 100.0  
2022 Spring Survey (202202)   Precision 9/2022 NS 473 87 4.15 89.7 n/s
2021 Commercial Samples (Q1-4)   Precision 4/2022 NS 269 50 0.00 100.0  
2021 Autumn Survey (202104)   Precision 4/2022 NS 269 50 0.00 100.0  
2021 Spring Survey (202102)   Precision 7/2021 NS 383 80 0.84 97.5  
2020 Commercial Samples (Q3)   Precision 3/2021 NS 141 40 0.39 97.5  
2020 Commercial Samples (Q2)   Precision 3/2021 NS 223 41 0.00 100.0  
2020 Commercial Samples (Q1)   Precision 9/2020 NS 243 48 0.00 100.0  
2019 Commercial Samples (Q4)   Precision 5/2020 NS 291 60 0.00 100.0  
2019 Commercial Samples (Q3)   Precision 4/2020 NS 288 60 0.52 96.7  
2019 Commercial Samples (Q2)   Precision 4/2020 NS 303 60 0.21 98.3  
2019 Commercial Samples (Q1)   Precision 4/2020 NS 379 73 0.28 98.6  
2019 Autumn Survey (201904)   Precision 2/2020 NS 202 42 0.00 100.0  
2019 Spring Survey (201902)   Precision 2/2020 NS 447 92 1.76 97.8  
2018 Autumn Survey (201804)   Precision 5/2019 NS 247 56 0.00 100.0  
2018 Commercial Samples (Q4)   Precision 5/2019 NS 395 79 0.00 100.0  
2018 Commercial Samples (Q3)   Precision 5/2019 NS 463 56 0.00 100.0  
2018 Commercial Samples (Q2)   Precision 5/2019 NS 974 80 0.00 100.0  
2018 Commercial Samples (Q1)   Precision 5/2019 NS 1116 77 0.00 100.0  
2018 Spring Survey (201802)   Precision 6/2018 NS 310 64 0.74 98.4  
2017 Commercial Samples (Q4)   Precision 5/2018 NS 826 89 0.00 100.0  
2017 Commercial Samples (Q3)   Precision 4/2018 NS 1218 84 0.00 100.0  
2017 Commercial Samples (Q2)   Precision 3/2018 NS 1243 68 0.16 98.5  
2017 Autumn Survey (201704)   Precision 2/2018 NS 212 48 0.00 100.0  
2017 Commercial Samples (Q1)   Precision 1/2018 NS 1463 105 0.00 100.0  
2017 Canadian (DFO) Spring Survey (TEL2017002) GB Exchange Spring 2017 QM vs. NS 62 4.00 79.0 0.011
2016 Canadian (DFO) Spring Survey (TEL2016002) GB Exchange Spring 2017 QM vs. NS 65 4.81 75.4 n/s
2016 Canadian (DFO) Commercial Samples (Q2-4) GB Exchange Spring 2017 QM vs. NS 114 3.46 82.5 n/s
2016 Commercial Samples (Q1-2) GB Exchange Spring 2017 QM vs. NS 152 2.36 84.9 n/s
2016 Autumn Survey (201604) GB Exchange Spring 2017 QM vs. NS 72 1.18 95.8  
2016 Commercial Samples (Q4)   Precision 7/2017 NS 1409 105 0.15 99.0  
2017 Spring Survey (201702)   Precision 7/2017 NS 659 94 0.00 100.0  
2016 Commercial Samples (Q3)   Precision 7/2017 NS 1201 86 0.00 100.0  
2016 Autumn Survey (201604)   Precision 5/2017 NS 667 78 0.00 100.0  
2016 Commercial Samples (Q2)   Precision 4/2017 NS 1314 96 0.00 100.0  
2016 Spring Survey (201602)   Precision 4/2017 NS 982 91 0.22 98.9  
2016 Commercial Samples (Q1)   Precision 3/2017 NS 2002 94 0.00 100.0  
2015 Commercial Samples (Q4)   Precision 4/2016 NS 1761 94 0.00 100.0  
2015 Commercial Samples (Q3)   Precision 4/2016 NS 824 95 0.00 100.0  
2015 Commercial Samples (Q2)   Precision 4/2016 NS 1034 95 0.00 100.0  
2015 Commercial Samples (Q1)   Precision 4/2016 NS 1561 93 0.00 100.0  
2015 Autumn Survey (201504)   Precision 4/2016 NS 813 94 0.00 100.0  
2015 Spring Survey (201502)   Precision 7/2015 NS 925 97 0.00 100.0  
Cod Reference Collection GB Accuracy 4/2015 NS 69 0.00 100.0  
2014 Autumn Survey (201404)   Precision 4/2015 NS 303 65 2.18 98.5  
2014 Spring Survey (201402)   Precision 4/2015 NS 478 96 0.00 100.0  
2014 Commercial Samples (Q4)   Precision 4/2015 NS 1072 97 0.00 100.0  
2014 Commercial Samples (Q3)   Precision 4/2015 NS 987 98 0.00 100.0  
2014 Commercial Samples (Q2)   Precision 4/2015 NS 1456 96 0.00 100.0  
2014 Commercial Samples (Q1)   Precision 4/2015 NS 1049 100 0.00 100.0  
2013 Commercial Samples (Q3-4)   Precision 4/2014 NS 3010 102 0.00 100.0  
2013 Commercial Samples (Q2)   Precision 4/2014 NS 1796 96 0.00 100.0  
2013 Autumn Survey (201304)   Precision 2/2014 NS 404 84 0.00 100.0  
2013 Commercial Samples (Q1)   Precision 1/2014 NS 1597 99 0.10 99.0  
2012 Commercial Samples (Q2-4) GOM Precision 11/2013 NS 2988 98 0.38 96.9  
2013 Spring Survey (201302)   Precision 10/2013 NS 697 97 4.95 81.4 0.015
2012 Commercial Samples (Q2-4) GB Precision 5/2013 NS 1345 98 1.48 92.9  
2012 Autumn Survey (201204)   Precision 4/2013 NS 383 80 0.35 98.8  
2012 Commercial Samples (Q1) GB Precision 12/2012 NS 499 50 1.10 92.0  
2012 Commercial Samples (Q1) GOM Precision 12/2012 NS 711 51 0.47 94.1  
2011 Massachusetts Survey (201191)   Precision 3/2012 NS 268 74 0.00 100.0  
2008 Commercial Samples (Q1-4) GOM Precision 10/2011 NS 4333 96 0.64 95.8  
2010 Commercial Samples (Q2-4) GOM Precision 9/2011 NS 4127 83 0.84 94.0  
2010 Commercial Samples (Q1) GOM Precision 9/2011 ER 1243 102 1.39 90.2  
2010 Commercial Samples (Q1) GOM Precision 9/2011 NS vs. ER 1243 101 4.13 66.3 <0.001
2009 Commercial Samples (Q2-4) GOM Precision 9/2011 NS 5260 92 1.68 85.9 0.030
2010 Canadian (DFO) Commercial Samples (Q2-Q4) &
2010 DFO Spring Surveys (NED201001 & NED201102)
GB Exchange Summer 2011 NS vs. BH 186 2.42 91.4  
2010 Commercial Samples (Q1-Q4) GB Precision 4/2011 NS 3548 146 0.39 97.3  
2009 Commercial Samples (Q1) GOM Precision 2/2011 NS 953 102 0.51 96.1  
2010 Spring Survey (201001)   Precision 2/2011 NS 932 96 1.26 93.8  
2008 Commercial Samples (Q4) GB Precision 5/2009 NS 559 76 0.00 100.0  
2008 Commercial Samples (Q2) GB Precision 4/2009 NS 659 50 0.13 98.0  
2008 Autumn Survey (200807)   Precision 3/2009 NS 390 50 2.18 92.0  
2003-2004 Massachusetts Surveys
(2391, 2392, 2491, & 2492)
  Precision 7/2008 NM 761 100 4.65 90.0  
2007 Commercial Samples (Q1-2) GB Exchange Spring 2008 NS vs. BH 99 1.80 88.9 n/s
2006 Fall Survey (200610) GB Exchange Spring 2008 NS vs. BH 60 2.83 88.3 n/s
2007 Commercial Samples (Q3-4)   Precision 6/2008 NS

3139

81 0.35 97.5  
2007 Commercial Samples (Q1-2)   Precision 6/2008 NS 3486 100 0.13 99.0  
Cod Reference Collection GB Accuracy 6/2008 NS 75 0.27 98.7  
2008 Spring Survey (200803)   Precision 6/2008 NS 548 100 0.11 99.0  
2007 Autumn Survey (200709)   Precision 6/2008 NS 250 50 0.00 100.0  
2004 Canadian (DFO) Commercial & Observer Samples (Q3-4) GB Exchange Spring 2007 NM/NS vs. BH 56 1.40 91.1  
2005 Canadian (DFO) Spring Survey (TEL2005545) GB Exchange Spring 2007 NM/NS vs. BH 50 0.89 94.0  
2005 Commercial Samples (Q1) GB Exchange Spring 2007 NM/NS vs. BH 53 2.28 84.9 n/s
2005 Autumn Survey (200510) GB Exchange Spring 2007 NM/NS vs. BH 56 1.79 91.1  
Cod Reference Collection GB Accuracy 5/2007 NS 100 0.61 97.0  
2006 Commercial Samples (Q1-4)   Precision 5/2007 NS 7039 99 1.01 90.9  
2006 Autumn Survey (200610) &
2007 Spring Survey (200703)
  Precision 5/2007 NS 1157 100 1.61 92.0  
Cod Reference Collection GB Accuracy 5/2006 NS 45 3.85 86.7 n/a
2006 Spring Survey (200604)   Precision 5/2006 NS 421 50 0.19 98.0  
2005 Commercial Samples (Q1-4)   Precision 5/2006 NS 5103 80 1.20 93.8  
2005 Autumn Survey (200510)   Precision 5/2006 NS 377 50 0.22 98.0  
2004 Commercial Samples (Q1-4) GOM Precision 7/2005 NS 3618 112 0.75 93.8  
2003 Canadian (DFO) Commercial Samples (Q4) &
2004 DFO Observer Samples (Q3)
GB Exchange Spring 2005 NM/NS vs. BH 50 0.88 94.0  
2004 Canadian (DFO) Spring Survey (TEM2004004) GB Exchange Spring 2005 NM/NS vs. BH 50 1.98 84.0 n/s
2004 Commercial Samples (Q2) GB Exchange Spring 2005 NM/NS vs. BH 51 3.59 80.4 n/s
2004 Autumn Survey (200407) GB Exchange Spring 2005 NM/NS vs. BH 49 2.59 85.7 n/s
Cod Reference Collection GB Accuracy 6/2005 NM 106 1.53 90.6  
2003 Commercial Samples (Q4) GOM Precision 4/2005 NS 1490 105 2.68 85.7 0.021
2004 Autumn Survey (200407) GOM Precision 2/2005 NM vs. NS 174 60 0.00 100.0  
Cod Reference Collection GB Accuracy 6/2004 NS 99 1.94 90.9  
2002 Canadian (DFO) Commercial Samples (Q3-4) GB Exchange Winter 2003-2004 NM/NS vs. BH 46 2.60 78.3 n/s
2003 Canadian (DFO) Spring Survey (NED2003002) GB Exchange Winter 2003-2004 NM/NS vs. BH 47 5.26 68.1 n/s
2002 Commercial Samples (Q1) GB Exchange Winter 2003-2004 NM/NS vs. BH 46 2.40 89.1 n/s
2002 Autumn Survey (200209) GB Exchange Winter 2003-2004 NM/NS vs. BH 52 3.83 88.5 n/s

Last updated by Northeast Fisheries Science Center on April 01, 2024

Age and Growth