43 3 Report on Sea Lice Epidemiology and Management in Ireland with Particular Reference to Potential Interactions with Wild Salmon (Salmo salar) and Freshwater Pearl Mussel (Margaritifera margaritifera) Populations Dave Jackson Pauline O’Donohoe Tom McDermott Frank Kane Suzanne Kelly Alan Drumm Surplus available for exploitation Bundorragha 1 SW Surplus available for exploitation Newport Surplus available for exploitation Ballynahinch Mean Ovigerous sea lice levels nationally (May) 3.0 Treatment trigger Level Mean ovigerous sea lice (SE) 2.5 2.0 1.5 1.0 0.5 0.0 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Mean Mobile sea lice levels nationally (May) Mean mobile sea lice (SE) 16 14 12 10 8 6 4 2 0 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 1200 1000 Returns (n) 800 600 400 200 0 Burr08 ii Burr08 i Control Returns Burr07 Burr06 ii Burr06 i Burr05 Burr04 Burr03 Burr02 Burr01 Batch / year SLICE Treatment Returns X^2 Signifcant difference 12 SLICE Treatment Control 10 % Survival 8 6 4 2 0 2008ii 2008i 2007 2006ii 2006i 2005 2004 2003 2002 2001 Year 12 Control 10 SLICE Treatment % Survival 8 Control mean 6 SLICE Treatment mean 4 Linear (Control) 2 0 2009 2007 2008 2006 2004 2005 2003 2002 2000 2001 Linear (SLICE Treatment) Year 12 Predicetd Control 10 Predicetd SLICE Treatment % Survival 8 6 Linear (Predicetd SLICE Treatment) 4 Linear (Predicetd Control) 2 0 2009 2008 2007 2006 2005 2004 2002 2003 2000 2001 Year 12 Common 10 Linear (Common) % Survival 8 6 4 2 0 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 Year 100 100 90 80 95 % Marine Mortality Control 70 Slice % Marine Mortality 60 50 40 90 85 30 20 10 80 2000 0 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2001 Control 2002 2003 2004 Year 2005 2006 2007 2008 2009 Slice Regression y = -19.131 + 0.003 * x r2 = 0.3198 Regression y = -34.522 + 0.003 * x r2 = 0.3754 +95% CL +95% CL -95% CL -95% CL Year • • • • • • • • • • • • Group Code Release Date 28/04/2003 28/04/2003 07/04/2004 07/04/2004 07/04/2005 07/04/2005 29/04/2003 29/04/2003 08/04/2003 08/04/2004 08/04/2005 08/04/2005 12/04/2004 12/04/2004 04/04/2005 04/04/2005 MicroTag Code 24780 24779 34793 34792 44789 44788 24782 24781 34795 34794 44787 44786 34796 34797 44784 44785 Control / Treated Stock Hatchery Release River Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Gowla Gowla Gowla Gowla Gowla Gowla Invermore Invermore Invermore Invermore Invermore Invermore Erriff Erriff Erriff Erriff Estimated Number Released 4822 4955 4699 4655 4735 4583 4594 4589 4671 4653 4750 4716 4229 4325 4689 4659 Total Tags Recovered Unraised Raised 3 35 22 51 53 54 9 17 26 37 17 31 34 44 2 37 20 226 91 165 318 306 38 89 96 105 111 196 108 102 8 172 Group Code Release Date MicroTag Code Control / Treated Stock Hatchery Release River Estimated Number Released Total Tags Recovered Unraised 02/05/2001 02/05/2001 02/05/2001 02/05/2001 26/04/2005 26/04/2005 29/04/2006 29/04/2006 26/04/2007 27/04/2007 44713 44714 44723 44724 44790 44791 54708 54713 54721 54722 Control Slice Control Slice Control Slice Control Slice Control Slice Burrishoole Burrishoole Delphi grilse Delphi grilse Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha 6385 6392 6395 6368 8893 8471 8788 10560 9719 9451 372 423 303 285 543 609 142 414 534 526 Delphi 08 DEL Delphi 08 DEL Delphi 08 DEL 28/04/2008 28/04/2008 28/04/2008 03/05/2001 03/05/2001 01/05/2002 01/05/2002 01/05/2002 01/05/2002 01/05/2002 01/05/2003 01/05/2003 29/04/2004 29/04/2004 28/04/2005 28/04/2005 26/04/2006 26/04/2006 26/04/2006 04/05/2006 04/05/2006 24/04/2007 24/04/2007 24/04/2007 29/04/2008 29/04/2008 06/05/2008 06/05/2008 54740 54749 54750 204713 A 204701 A 34705 A 34706 A 184747 B 184761 B 34707 A 24774 24777 44764 34788 54702 A 44724 A 14782 A 14764 A 24782 A 24791 A 24783 A 44764a 34792a 34798a 34777a 54741 14781a 24767a Control Slice Slice Control Slice Control Control control Slice Slice Control Slice Control Slice Control Slice Control Control Slice Control Slice Control Control Slice Control Slice Control Slice Delphi grilse Delphi grilse Delphi grilse Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Delphi Delphi Delphi Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Bundorragha Bundorragha Bundorragha Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole 10811 10551 5795 10039 5496 3079 1596 1314 4748 1212 4587 4745 4369 4437 3867 3793 4299 480 4809 8000 3907 3391 3393 6746 6832 6719 3392 3413 175 160 119 416 259 160 77 58 248 55 126 145 151 162 96 114 180 31 326 334 180 229 211 491 76 97 54 72 28/04/2009 28/04/2009 04/04/2006 04/04/2006 28/04/2006 28/04/2006 04/05/2006 04/05/2006 54754 54755 24779 A 24780 A 54707 54716 54715 54714 Control Slice Control Slice Control Slice Control Slice Burrishoole Burrishoole Lee Lee Screebe Screebe Erne Erne Burrishoole Burrishoole Carrigadrohid Carrigadrohid Screebe Screebe Ballyshannon Ballyshannon Burrishoole Burrishoole Lee Lee Screebe Screebe Erne Erne 6640 6881 5131 5207 9618 10990 10357 5752 300 267 10 10 121 157 68 70 Burr 09 Burr 09 Raised 985 1217 892 836 183 167 126 565 287 138 117 456 89 374 471 398 403 183 253 180 31 326 334 180 229 211 491 76 97 54 72 300 267 10 10 121 157 68 70 24780 24779 34793 34792 44789 44788 24782 24781 34795 34794 44787 44786 34796 34797 44784 44785 44713 44714 44723 44724 44790 44791 54708 54713 54721 54722 54740 54749 54750 204713 A 204701 A 34705 A 34706 A 184747 B 184761 B 34707 A 24774 24777 44764 34788 54702 A 44724 A 14782 A 14764 A 24782 A 24791 A 24783 A 44764a 34792a 34798a 34777a 54741 14781a 24767a 54754 54755 24779 A 24780 A 54707 54716 54715 54714 28/04/2003 28/04/2003 07/04/2004 07/04/2004 07/04/2005 07/04/2005 29/04/2003 29/04/2003 08/04/2003 08/04/2004 08/04/2005 08/04/2005 12/04/2004 12/04/2004 04/04/2005 04/04/2005 02/05/2001 02/05/2001 02/05/2001 02/05/2001 26/04/2005 26/04/2005 29/04/2006 29/04/2006 26/04/2007 27/04/2007 28/04/2008 28/04/2008 28/04/2008 03/05/2001 03/05/2001 01/05/2002 01/05/2002 01/05/2002 01/05/2002 01/05/2002 01/05/2003 01/05/2003 29/04/2004 29/04/2004 28/04/2005 28/04/2005 26/04/2006 26/04/2006 26/04/2006 04/05/2006 04/05/2006 24/04/2007 24/04/2007 24/04/2007 29/04/2008 29/04/2008 06/05/2008 06/05/2008 28/04/2009 28/04/2009 04/04/2006 04/04/2006 28/04/2006 28/04/2006 04/05/2006 04/05/2006 MicroTag Code Release Date Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Slice Control Slice Control Control control Slice Slice Control Slice Control Slice Control Slice Control Control Slice Control Slice Control Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control Slice Control / Treated Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Burrishoole Burrishoole Delphi grilse Delphi grilse Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Delphi grilse Delphi grilse Delphi grilse Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Lee Lee Screebe Screebe Erne Erne Stock Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Cong Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Delphi Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Carrigadrohid Carrigadrohid Screebe Screebe Ballyshannon Ballyshannon Hatchery Gowla Gowla Gowla Gowla Gowla Gowla Invermore Invermore Invermore Invermore Invermore Invermore Erriff Erriff Erriff Erriff Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Bundorragha Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Burrishoole Lee Lee Screebe Screebe Erne Erne Release River 4822 4955 4699 4655 4735 4583 4594 4589 4671 4653 4750 4716 4229 4325 4689 4659 6385 6392 6395 6368 8893 8471 8788 10560 9719 9451 10811 10551 5795 10039 5496 3079 1596 1314 4748 1212 4587 4745 4369 4437 3867 3793 4299 480 4809 8000 3907 3391 3393 6746 6832 6719 3392 3413 6640 6881 5131 5207 9618 10990 10357 5752 Estimated Number Released 0 3 0 4 2 2 4 2 2 6 1 0 4 16 0 0 11 15 13 11 1 3 0 0 0 0 0 0 0 11 9 9 4 1 11 3 10 13 12 14 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Donegal 1 6 4 8 5 6 1 4 7 5 2 2 5 10 0 4 85 103 70 71 2 4 0 0 0 0 0 0 0 82 47 32 10 16 66 10 11 18 27 32 6 7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Mayo 2 24 10 15 30 26 3 8 8 7 10 18 7 2 1 12 109 146 120 104 49 68 11 25 56 41 6 6 8 62 29 23 6 4 32 5 24 26 16 11 0 5 0 0 0 0 0 1 0 0 0 0 0 0 1 1 0 0 0 0 0 0 Gal / Lim 0 1 0 0 0 0 0 0 0 1 0 2 0 0 0 1 1 1 3 3 0 0 0 0 0 0 0 0 0 10 4 1 1 0 1 0 1 3 1 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Kerry 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 1 2 3 0 1 0 0 0 0 0 0 0 0 0 11 6 0 1 1 0 0 2 4 8 6 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 W Cork 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 S Coast 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 SE Coast 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Other 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 N Irl 0 0 0 0 11 8 0 0 0 0 1 0 0 0 1 13 0 0 0 0 0 0 0 0 0 0 138 138 93 150 98 23 17 8 33 7 11 18 48 43 38 41 75 13 137 142 68 227 209 491 76 97 54 72 298 266 0 0 3 0 0 0 Trap 0 0 3 10 0 0 0 0 0 0 0 0 2 1 0 5 37 47 9 10 158 171 42 114 113 137 29 9 15 2 3 0 1 0 0 0 12 11 2 8 10 8 13 3 34 20 13 0 0 0 0 0 0 0 0 0 0 0 18 20 0 0 Rods 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Draft 0 0 3 11 0 0 1 0 6 14 0 0 12 12 0 0 125 106 87 84 296 318 86 265 361 341 0 0 0 80 61 69 37 28 105 30 55 51 37 42 39 52 92 15 155 171 99 0 0 0 0 0 0 0 0 0 10 10 100 136 67 70 Brood 0 1 2 3 5 12 0 3 3 4 3 8 3 3 0 1 2 1 0 1 37 45 3 10 4 7 2 7 3 5 0 2 0 0 0 0 0 0 0 1 1 0 0 0 0 1 0 1 2 0 0 0 0 0 1 0 0 0 0 0 0 0 Stray 3 35 22 51 53 54 9 17 26 37 17 31 34 44 2 37 372 423 303 285 543 609 142 414 534 526 175 160 119 416 259 160 77 58 248 55 126 145 151 162 96 114 180 31 326 334 180 229 211 491 76 97 54 72 300 267 10 10 121 157 68 70 Total tags Recovered unraised Year Mean ovigerous L. salmonis per fish Standard Error Mean mobile L. salmonis per fish Standard Error 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 1.21 2.34 1.50 0.53 0.53 1.01 1.17 1.30 0.89 0.68 0.21 0.73 0.73 0.58 1.07 1.39 1.74 0.68 0.77 0.72 0.35 0.45 0.19 0.44 0.34 0.23 0.10 0.11 0.24 0.21 0.23 0.14 0.13 0.04 0.12 0.13 0.13 0.25 0.29 0.32 0.16 0.12 0.16 0.10 0.08 0.04 10.19 12.15 9.87 4.61 4.39 11.56 7.27 8.97 7.86 3.91 1.10 4.26 4.84 2.28 5.12 8.65 12.35 8.81 7.42 5.11 1.51 2.84 0.89 2.74 1.78 1.31 0.66 0.72 1.84 1.21 1.55 1.18 0.71 0.21 0.74 0.94 0.51 1.34 1.93 2.21 2.99 1.49 0.98 0.37 0.58 0.17
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