Last updated on 14 October 2016

SUMMARY

SUMMARY

IDENTIFICATION

SCIENTIFIC NAME(s)

Raja ocellata

SPECIES NAME(s)

Winter skate

Winter skate is part of the Northeast Skate Complex Fisheries that integrates seven skate species: barndoor skate (Dipturus laevis), clearnose skate (Raja eglanteria), little skate (Leucoraja erinacea), rosette skate (Leucoraja garmanii), smooth skate (Malacoraja senta), thorny skate ( Amblyraja radiata ), and winter skate (Leucoraja ocellata).

This profile is only for winter skate as a subset of this complex.


ANALYSIS

Strengths
  • Biomass is at target levels for the complex
  • Stock is not overfished and overfishing is not occuring.
  • Mangers set precautionary quotas for the complex.
  • Harvesters have not achieved quotas in recent years.
  • PET and bycatch interactions and issues have been mitigated by ongoing management action.
  • Gillnets tend to not have a lot of habitat impacts.
Weaknesses
  • Some PET stocks experiencing higher levels of removals than advised.
  • No analytic assessment available so stock status determined solely from bottom trawl index.
  • Stock Status highly uncertain
  • Quotas and landings are set on a complex wide basis; the potential exists for depletion of individual stocks under this regime.
Options


Suggest research into better better species identification to promote species by species assessment and quota setting.
Promote research into utilizing more analytic methods and reference points which incorporate uncertainty.
Continue setting precautionary quotas.
Continue and enhance work on bycatch documentation and PET species mitigation measures.

FISHSOURCE SCORES

Management Quality:

Management Strategy:

≥ 8

Managers Compliance:

≥ 8

Fishers Compliance:

≥ 8

Stock Health:

Current
Health:

8.7

Future Health:

≥ 8


RECOMMENDATIONS

CATCHERS & REGULATORS

1. Start a fishery improvement project to address sustainability issues in this fishery. For advice on starting a FIP, see SFP’s Seafood Industry Guide to FIPs at http://www.sustainablefish.org/publications/2014/04/30/the-seafood-industry-guide-to-fips.
2. Communicate to fishery managers that there are sustainability issues in this fishery that may be affecting the sale of products, and request that they comprehensively evaluate and address such issues.

RETAILERS & SUPPLY CHAIN

1. Encourage your supply chain to start a fishery improvement project. For advice on starting a FIP see SFP’s Seafood Industry Guide to FIPs at http://www.sustainablefish.org/publications/2014/04/30/the-seafood-industry-guide-to-fips.
2. Work with other suppliers and buyers on a pre-competitive basis to start a supplier roundtable to review improvement needs in this and other similar fisheries, catalyze fishery improvement projects, and monitor progress in improvement efforts.


FIPS

No related FIPs

CERTIFICATIONS

No related MSC fisheries

Fisheries

Within FishSource, the term "fishery" is used to indicate each unique combination of a flag country with a fishing gear, operating within a particular management unit, upon a resource. That resource may have a known biological stock structure and/or may be assessed at another level for practical or jurisdictional reasons. A fishery is the finest scale of resolution captured in FishSource profiles, as it is generally the scale at which sustainability can most fairly and practically be evaluated.

ASSESSMENT UNIT MANAGEMENT UNIT FLAG COUNTRY FISHING GEAR
NW Atlantic United States United States Bottom trawls
Gillnets and entangling nets

Analysis

OVERVIEW

Last updated on 21 October 2017

Strengths
  • Biomass is at target levels for the complex
  • Stock is not overfished and overfishing is not occuring.
  • Mangers set precautionary quotas for the complex.
  • Harvesters have not achieved quotas in recent years.
  • PET and bycatch interactions and issues have been mitigated by ongoing management action.
  • Gillnets tend to not have a lot of habitat impacts.
Weaknesses
  • Some PET stocks experiencing higher levels of removals than advised.
  • No analytic assessment available so stock status determined solely from bottom trawl index.
  • Stock Status highly uncertain
  • Quotas and landings are set on a complex wide basis; the potential exists for depletion of individual stocks under this regime.
Options


Suggest research into better better species identification to promote species by species assessment and quota setting.
Promote research into utilizing more analytic methods and reference points which incorporate uncertainty.
Continue setting precautionary quotas.
Continue and enhance work on bycatch documentation and PET species mitigation measures.

RECOMMENDATIONS

Last updated on 28 June 2016

Improvement Recommendations to Catchers & Regulators

1. Start a fishery improvement project to address sustainability issues in this fishery. For advice on starting a FIP, see SFP’s Seafood Industry Guide to FIPs at http://www.sustainablefish.org/publications/2014/04/30/the-seafood-industry-guide-to-fips.
2. Communicate to fishery managers that there are sustainability issues in this fishery that may be affecting the sale of products, and request that they comprehensively evaluate and address such issues.

Recommendations to Retailers & Supply Chain

1. Encourage your supply chain to start a fishery improvement project. For advice on starting a FIP see SFP’s Seafood Industry Guide to FIPs at http://www.sustainablefish.org/publications/2014/04/30/the-seafood-industry-guide-to-fips.
2. Work with other suppliers and buyers on a pre-competitive basis to start a supplier roundtable to review improvement needs in this and other similar fisheries, catalyze fishery improvement projects, and monitor progress in improvement efforts.

1.STOCK STATUS

STOCK ASSESSMENT
United States

Last updated on 21 October 2017

The first benchmark assessment of the seven species in the managed skate complex was conducted in October 2006 (NEFSC, 2007). Due to uncertainties about species identification in the commercial catch and a lack of aging and life history data, no analytic models were attempted. As such, the status determination was and is now based on the NEFSC bottom trawl survey time series using biological reference points adopted by the Council in the Skate Fisheries Management Plan (FMP) (NEFSC, 2013). The most recent assessment was conducted in 2017 (NEFMC 2017)(NEFSC 2017)(SAI Global 2015).

Because the assessment is not stock specific and indexed based, results are highly uncertain due to the survey’s variability. Discards are a major source of uncertainty (NEFSC 2017)

SCIENTIFIC ADVICE
United States

Last updated on 21 October 2017

Amendment 3 became effective in 2010, implementing a new ACL (Annual Catch Limit) management framework that capped catches at specific levels determined from survey biomass indices and median exploitation ratios. The amendment established a two-year specification cycle and also has accountability measures (adjustments to account for prior overages) and technical measures to reduce the skate possession limits (NEFMC/NMFS, 2012 & NEFSC, 2013).

Advice is based on performance as measured by the NEFSC autumn trawl survey. The three-year running average of this index is compared against management reference points to determine the status of the biomass. Changes in this three-year running average are used to infer fishing mortality  (NEFSC 2017).

Reference Points

Last updated on 21 Oct 2017

Without an analytically derived assessment, and because of uncertainty around catch identification, biomass reference points and status are based on results of the NEFSC Autumn Trawl Survey. For winter skate the target biomass is the 75th percentile of the survey value from 1967-2007 as a proxy for Bmsy. Correspondingly the biomass limit reference point at the point where management action is initiated is the median of that same timeframe as a proxy of ½ Bmsy.  Overfishing (or fishing mortality) reference points were based on the change in the survey. A negative change of >20% is considered to be overfishing(NEFMC 2009).

Currently the biomass index target is 5.66 while the biomass index threshold is 2.83 (NEFSC 2017).

CURRENT STATUS
United States

Last updated on 21 October 2017

Winter skate are not considered overfished as the three-year running average index (6.65) is well above the biomass index target (5.66). Winter skate are also not experiencing overfishing, as the three-year biomass index has increased each year over the past three years (NEFMC 2017)(NEFSC 2017).

Trends

Last updated on 21 Oct 2017

Overall catch has been in slight decline since a recent peak in 2010.However the amount of discards has dropped in 2016, while removals have remained relatively stable; suggesting an increase in retention. Overall dead discards account for 25% of the removals for Winter skate.

The three-year biomass index has increased each year for the last three years, while the annual index has increased each year over the same timeframe (NEFMC 2017)(NEFSC 2017). As such both the biomass and the removal rate appear to be in line with management objectives.

2.MANAGEMENT QUALITY

MANAGEMENT
United States

Last updated on 21 October 2017

In New England and the Mid-Atlantic, skates are typically harvested with otter trawls and gillnets, and are managed using annual catch limits, permit restrictions, trip limits, gear restrictions, at-sea observers, and mandatory reporting (NEFMC 2009).

However, quotas are set on the entire skate complex rather than induvial species (NEFMC 2009). As such, these quotas may not be as effective as measures which directly address winter skate specifically. Overall managers have followed scientific advice and set precautionary quotas complex-wide. Managers may wish consider species by species quotas rather than complex-based measures (NEFMC 2017)(NEFSC 2017)(SAI Global 2015).

Recovery Plans

Last updated on 21 Oct 2017

A rebuilding intent  is place in the fishery plan (NEFMC 2009)(NEFMC 2017)(SAI Global 2015) but until the stock is overfished a rebuilding timeframe and catch reductions are not made. It should be noted that measures to reduce catch across all species in the skate complex is not as effective as reducing catch on winter skate alone. Currently a rebuilding plan is not necessary (NEFMC 2016)(NEFMC 2017)(NEFSC 2017)(SAI Global 2015).

COMPLIANCE
United States

Last updated on 21 October 2017

Skates are mostly harvested incidentally in trawl and gillnet fisheries targeting groundfish, monkfish, and sometimes scallops. Some direct fishing occurs in the Mid-Atlantic and Southern New England Area for bait using gillnets. The principal commercial fishing method in the skate fishery is otter trawling, with some landings coming from sink gill nets. Recreational and foreign landings are currently insignificant (NFSC, 2007). Skates are harvested for their wings for human consumption, and small skates are harvested as bait for the lobster fishery (NEFMC, 2012).

Harvesters have recently be subjected to intense at-sea monitoring to measure discards as a result of management actions in the New England Multispecies/groundfish fishery. Also, harvesters have been landing skate well within the agreed quota (NEFMC, 2013)(NEFMC 2016)(NEFMC 2017)(NEFMC 2017)(NEFSC 2017)(SAI Global 2015).

3.ENVIRONMENT AND BIODIVERSITY

BYCATCH
ETP Species

Last updated on 21 October 2017

The directed large and smaller mesh gill net fishery impacts Bottlenose dolphin, Common dolphin, Fin whale, Gray seal, Harbor porpoise, Harbor seal, Harp seal, Hooded seal, Humpback whale, Minke whale, North Atlantic right whale, Risso’s dolphin, White-sided dolphin, and Atlantic Sturgeon as a category 1 fishery (Fisheries 2017). Overall this gear type is responsible for over 50% Potential Biological Removal (PBR) level. However, gear modifications (weak links, pingers, and excluders), closed areas, and other management actions are in place to limit and reduce incidents of mortality. The most recent indication (NMFS 2017) suggests that while target mortality rates for some PET species/stock is being exceeded, that populations are mostly still rebuilding. The one exception for this being Right whale populations which have been experiencing higher mortality, though not directly attributable to gill net gear specifically (Fisheries 2017)(NEFMC 2017)(NMFS 2017)(SAI Global 2015).

Trawl gear is listed as a category two fishery, with occasional interactions with some of the species listed above (Fisheries 2017). Both gear types do have interactions with Atlantic Sturgeon, an endangered species in US waters, though the scope and extent are not well known (NEFMC 2009)(NEFMC 2017)(SAI Global 2015).

Other Species

Last updated on 21 October 2017

The directed gillnet fishery and the trawl fishery both predominately use large mesh, and as such does not have much in the way of discards. A smaller mesh gillnet fishery does have significant bycatch and incidental catch associated with it. While bycatch in the later is substantial, much of this incidental catch is now retained and counted against the individual species quota as part of the NE Multispecies/groundfish fishery. Both fisheries are subject to closure should these others stock achieve their yearly quota. At-sea monitoring has increased substantial in recent years. Seasonal closures and effort controls are also used to minimize impacts (NEFMC 2014b, and (NEFMC 2009)(NEFMC 2017)(SAI Global 2015))

HABITAT

Last updated on 21 October 2017

The directed gillnet fishery has little bottom impact with the possible exception of deep-water coral. However, managers have recently exempted this fishery from some the deep-water habitats. Trawl fisheries however are not exempt (NEFMC 2009)(NEFMC 2017)(NEFMC 2017)(SAI Global 2015)

Marine Reserves

Last updated on 21 Oct 2017

Stellwagen Bank as well as other areas are completely closed to this fishery as well as other gear types in the NE groundfish fishery. As such there is a network of areas closed to all fishing gears through the region, to protect habitat, reduce fishing mortality on juvenile fishes, and to conserve discreet spawning units (NEFMC, 2014b (NEFMC 2009)(NEFMC 2017)(NEFMC 2017)(SAI Global 2015)).

FishSource Scores

Last updated on 21 October 2017

MANAGEMENT QUALITY

As calculated for 2016 data.

The score is ≥ 8.

There is a Fishery Management plan in place. Annual Catch Limit (ACL) is in place that capped catches at specific levels determined from survey biomass indices and median exploitation ratios. The management also considers accountability measures (adjustments to account for prior overages) and technical measures to reduce the skate possession limits.

As calculated for 2016 data.

The score is ≥ 8.

Quota is based on the skate complex and is not broken out by species. Managers do follow the advice for the overall complex.

As calculated for 2016 data.

The score is ≥ 8.

Quotas are based on the skate complex and are not broken out by species. Harvesters follow set regulations for the complex as a whole

STOCK HEALTH:

As calculated for 2016 data.

The score is 8.7.

This measures the Biomass index as a percentage of the Biomass target.

The Biomass index is 6.65 . The Biomass target is 5.66 .

The underlying Biomass index/Biomass target for this index is 117%.

As calculated for 2016 data.

The score is ≥ 8.

The most recent stock assessment indicates that winter skate is not overfished, and that overfishing is not occurring

To see data for biomass, please view this site on a desktop.
To see data for catch and tac, please view this site on a desktop.
To see data for fishing mortality, please view this site on a desktop.
No data available for recruitment
No data available for recruitment
To see data for management quality, please view this site on a desktop.
To see data for stock status, please view this site on a desktop.
DATA NOTES
  • Catch is for winter skate while quotas are based on the entire skate complex which includes many species other than winter skate
  • Assessment uses the three-year running average of a survey index to determine biomass relative to chosen reference points. A change in that three-year average greater than negative 20% reflects overfishing or increased fishing mortality.
  • Because quotas are set on the complex as a whole, rather than by induvial species, and because of how stock status is determined vs reference points; scores 1-3 and 5 were determined qualitatively.

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Fishery Improvement Projects (FIPs)

No related FIPs

Certifications

Marine Stewardship Council (MSC)

No related MSC certifications

Sources

Credits
  1. NEFMC, 2012. 2012 Annual Monitoring Report Northeast Skate Complex Fishery Management Plan. 6pp http://www.nefmc.org/skates/annual_reviews/2012%20Skate%20Annual%20Monitoring%20Report%20Final.pdf
  2. NEFMC, 2012b. Northeast Skate Complex Specifications Environmental Assessment Regulatory Impact Review and Initial Regulatory Flexibility Analysis. New England Fishery Management Council.http://nefmc.org/skates/Skate%202012_2013%20specifications%20doc%20final%20MAR%2020.pdf
  3. NEFMC, 2014b Omnibus Essential Fish Habitat Amendment 2, New England Fishery Management Council. Volumes 1-5. http://www.nefmc.org/habitat/index.html
  4. NEFMC, 2014. Framework Adjustment 2 To the Northeast Skate Complex FMP Draft Management Measures. New England Fishery Management Council. http://nefmc.org/skates/council_mtg_docs/Jan%202014/1_draft%20Framework%202.pdf
  5. NEFMC/NMFS, 2012.2012-2013 Northeast Skate Complex Specifications, Environmental Assessment Regulatory,Impact Review and Initial Regulatory Flexibility Analysis. March 2012. 217pphttps://www.nero.noaa.gov/nero/regs/frdoc/12/12Skate2012SpecsEA.pdf
  6. NEFSC, 2007. 44th Northeast Regional Stock Assessment Workshop (44th SAW): 44th SAW assessment report. US Dep Commer, Northeast Fish Sci Cent Ref Doc 07-10; 661 p.http://www.nefsc.noaa.gov/publications/crd/crd0710/
  7. NEFSC, 2013. Memorandum: Update of Skate Stock Status Based on the NEFSC Bottom Trawl Survey Through Autumn 2012 and Spring 2013 http://nefmc.org/tech/cte_mtg_docs/131115/skates/2_NEFSC_UpdateSkateStocks2013.pdf
  8. NMFS, 2013. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments – 2012http://www.nmfs.noaa.gov/pr/sars/pdf/ao2012.pdf
  9. NOAA, 2014.Greater Atlantic region. Northeast Skate Complex - Quota. 2012-2013 Skate Specifications http://www.nero.noaa.gov/sustainable/species/skate/
  10. NOAA, undated. Northeast Skate Information Sheet. NOAA Fisheries Suitainable Fisheries. Available online at http://www.nero.noaa.gov/regs/infodocs/neskateinfosheet.pdf
  11. Sosebee, K., Applegate, A., Brooks, E., Gedamke, T., Traver, M., 2008. Skate Species Complex: Examination of Potential Biological Reference Points for the Northeast Region. Northeast Data Poor Stocks Working Group Meeting, December 8-12, 2008. 18pp http://www.nefsc.noaa.gov/publications/crd/crd0902/skates/skateText.pdf
References

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