Fiona Hogan, NEFMC Staff Skate PDT Chair
Fiona Hogan, NEFMC Staff Skate PDT Chair SSC Meeting August 8, 2017
Northeast Skate Complex
Seven Species
Barndoor Clearnose Little Rosette Smooth Thorny Winter
Distributions range from Gulf of Maine to Florida
Specifications – Key components
Survey indices
Discards
Catch/biomass medians
ACL = ABC 31,081 mt Management Uncertainty
ACT = 75% of ACL 23,311mt Projected Dead Discards (43%)
State Landings (2.6%)
TAL = ACT – Discards – State Landings 12,872 mt
Wing TAL e.g. 66.5% = 8,560 mt
Bait TAL e.g. 33.5% = 4,312 mt
Skate Complex Biomass Indices 16
Survey Indices
4
Updated Survey Indices
8
Increased indices for 2 of 7 species on 2015/16 Overfishing not occurring Overfished: thorny
Discard mortality rate estimate
Sulikowski et al. under review
10 8 6
Little Skate
4 2
Barndoor Skate 2
NEFSC Biomass Index (kg/tow)
Winter Skate
12
1
Thorny Skate
8 6 4 2
0.8 0.6
Smooth Skate
0.4 0.2
1.5
Clearnose Skate
1.0 0.5
0.12 0.10 0.08 0.06 0.04 0.02
Rosette Skate
1960
1965
1970
1975
1980
1985
1990
Year
1995
2000
2005
2010
2015
Sink Gillnet Discard Study
Tows
28 trips Soak time duration: 2-5 days up to 14 days
72 – 285 hour holding period Discard mortality
Sex specific final estimates Female = 11% Male = 17% Average = 14%
Amendment 3: Control Rule
Uses the median catch/biomass ratio as an estimate of exploitation rate applied to the threeyear moving average of fall survey stratified mean kg/tow (spring survey for little skate).
ACL = ABC 31,327 mt Management Uncertainty
ACT = 75% of ACL 23,495 mt Projected Dead Discards (41%)
State Landings (3.5%)
TAL = ACT – Discards – State Landings 13,281 mt
Wing TAL e.g. 66.5% = 8,832 mt
Bait TAL e.g. 33.5% = 4,449 mt
Comparison of specifications PDT recommendation including sink gillnet discard estimate
Status Quo discard mortality rate estimates
FY 2015-17 specifications
ABC
31,327
31,913
31,081 mt
ACT
23,495
23,935
23,311 mt
TAL
13,762
13,914
12,926 mt
Federal TAL
13,281
13,427
12,872 mt
Wing TAL
8,832
8,929
8,560 mt
Bait TAL
4,449
4,498
4,312 mt
Catch 2014
2015
Management Specification
Specification Amount
Catch/Landings Specification (mt) Amount
Catch/Landings
ABC/ACL
35,479
28,032
35,479
28,111
ACT
26,609
28,032
26,609
28,111
Assumed Discards + State Landings
16,385
11,781
16,385
11,781
TAL (Bait + Wing) TAL Bait
23,365
15,104
23,365
14,452
5,489
4,499
5,489
5,541
TAL Wings
10,896
10,605
10,896
8,911
Timeline
August 2017 – SSC approval of ABC
August – Sept 2017 - PDT/Committee develop measures
Sept 2017/Dec 2017 – final vote by Council
May 2018 - Implementation
Questions? Suggestions?
Northeast Skate Complex
Seven Species
Barndoor Clearnose Little Rosette Smooth Thorny Winter
Distributions range from Gulf of Maine to Florida
Specifications – Key components
Survey indices
Discards
Catch/biomass medians
ACL = ABC 31,081 mt Management Uncertainty
ACT = 75% of ACL 23,311mt Projected Dead Discards (43%)
State Landings (2.6%)
TAL = ACT – Discards – State Landings 12,872 mt
Wing TAL e.g. 66.5% = 8,560 mt
Bait TAL e.g. 33.5% = 4,312 mt
Skate Complex Biomass Indices 16
Survey Indices
4
Updated Survey Indices
8
Increased indices for 2 of 7 species on 2015/16 Overfishing not occurring Overfished: thorny
Discard mortality rate estimate
Sulikowski et al. under review
10 8 6
Little Skate
4 2
Barndoor Skate 2
NEFSC Biomass Index (kg/tow)
Winter Skate
12
1
Thorny Skate
8 6 4 2
0.8 0.6
Smooth Skate
0.4 0.2
1.5
Clearnose Skate
1.0 0.5
0.12 0.10 0.08 0.06 0.04 0.02
Rosette Skate
1960
1965
1970
1975
1980
1985
1990
Year
1995
2000
2005
2010
2015
Sink Gillnet Discard Study
Tows
28 trips Soak time duration: 2-5 days up to 14 days
72 – 285 hour holding period Discard mortality
Sex specific final estimates Female = 11% Male = 17% Average = 14%
Amendment 3: Control Rule
Uses the median catch/biomass ratio as an estimate of exploitation rate applied to the threeyear moving average of fall survey stratified mean kg/tow (spring survey for little skate).
ACL = ABC 31,327 mt Management Uncertainty
ACT = 75% of ACL 23,495 mt Projected Dead Discards (41%)
State Landings (3.5%)
TAL = ACT – Discards – State Landings 13,281 mt
Wing TAL e.g. 66.5% = 8,832 mt
Bait TAL e.g. 33.5% = 4,449 mt
Comparison of specifications PDT recommendation including sink gillnet discard estimate
Status Quo discard mortality rate estimates
FY 2015-17 specifications
ABC
31,327
31,913
31,081 mt
ACT
23,495
23,935
23,311 mt
TAL
13,762
13,914
12,926 mt
Federal TAL
13,281
13,427
12,872 mt
Wing TAL
8,832
8,929
8,560 mt
Bait TAL
4,449
4,498
4,312 mt
Catch 2014
2015
Management Specification
Specification Amount
Catch/Landings Specification (mt) Amount
Catch/Landings
ABC/ACL
35,479
28,032
35,479
28,111
ACT
26,609
28,032
26,609
28,111
Assumed Discards + State Landings
16,385
11,781
16,385
11,781
TAL (Bait + Wing) TAL Bait
23,365
15,104
23,365
14,452
5,489
4,499
5,489
5,541
TAL Wings
10,896
10,605
10,896
8,911
Timeline
August 2017 – SSC approval of ABC
August – Sept 2017 - PDT/Committee develop measures
Sept 2017/Dec 2017 – final vote by Council
May 2018 - Implementation
Questions? Suggestions?
