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«©Monterey Bay Aquarium U.S. Pacific Bottom gillnet, Bottom trawl, Hook and line November 4, 2013 Kelsey James, Consulting Researcher Disclaimer ...»

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California Halibut

Paralichthys californicus

©Monterey Bay Aquarium

U.S. Pacific

Bottom gillnet, Bottom trawl, Hook and line

November 4, 2013

Kelsey James, Consulting Researcher

Disclaimer

Seafood Watch® strives to ensure all our Seafood Reports and the recommendations contained therein are

accurate and reflect the most up-to-date evidence available at time of publication. All our reports are peer-

reviewed for accuracy and completeness by external scientists with expertise in ecology, fisheries science or aquaculture. Scientific review, however, does not constitute an endorsement of the Seafood Watch program or its recommendations on the part of the reviewing scientists. Seafood Watch is solely responsible for the conclusions reached in this report. We always welcome additional or updated data that can be used for the next revision.

Seafood Watch and Seafood Reports are made possible through a grant from the David and Lucile Packard Foundation.

2 Final Seafood Recommendation Stock / Fishery Impacts on Impacts on Management Habitat and Overall the Stock other Spp. Ecosystem Recommendation California halibut: Southern Yellow Yellow (3.00) Good Alternative Red (2.05) Yellow (3.00) California (2.643) (2.64) California: Southern Northeast Pacific - Trawl, Bottom California halibut: Southern Yellow Green (3.46) Best Choice (3.380) Green (4.75) Yellow (3.00) California (2.64) California: Southern Northeast Pacific - Hook/line California halibut: Southern Yellow Green (3.46) Good Alternative Red (1.82) Yellow (3.00) California (2.659) (2.64) California: Southern Northeast Pacific - Gillnet, Bottom California halibut: Central Green (4.28) Green (4.75) Yellow (3.00) Green (3.46) Best Choice (3.813) California California: Central Northeast Pacific - Hook/line California halibut: Central Green (4.28) Red (1.94) Yellow (3.00) Yellow (3.00) Good Alternative California (2.942) California: Central Northeast Pacific - Trawl, Bottom Scoring note – scores range from zero to five where zero indicates very poor performance and five indicates the fishing operations have no significant impact. Final Score = geometric mean of the four Scores (Criterion 1, Criterion 2, Criterion 3, Criterion 4).

Best Choice = Final Score between 3.2 and 5, and no Red Criteria, and no Critical scores Good Alternative = Final score between 2.2 and 3.199, and Management is not Red, and no more than one Red Criterion other than Management, and no Critical scores

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Executive Summary California halibut (Paralichthys californicus) are found off the Quillayute River, Washington to southern Baja California, but are most common from Bodega Bay, California and south. This report addresses the bottom gillnet, hook and line, and bottom trawl fisheries for this species throughout its range.

California halibut has a moderate inherent vulnerability based on a productivity and susceptibility analysis (PSA). The first ever stock assessment was published in 2011 indentifying two stocks: a southern and a central stock. Bottom trawl and hook and line fish both stocks, while bottom gillnet only fishes the southern stock. The southern stock was estimated as depleted to 14% of the unexploited biomass, but the biomass has remained constant since the 1970s therefore it is of moderate concern since there are no reference points to compare with.

The central stock was estimated at 122% of the unexploited biomass and is of very low concern.

The fishing mortality for both stocks was estimated below the level that would prodice maximum sustainable yield (MSY), although the appropriateness of MSY as a reference point is in question. Due to the unknown fishing mortality in relation to an appropriate reference point the fishing mortality is of moderate concern for both stocks.

The humpback whale has the lowest scores overall, but is only subject to entanglement in the gillnet fishery. It has a high inherent vulnerability and a high stock status concern because it is listed as endangered on the endangered species list. The humpback whale has low fishing mortality based on the combination of very low known entanglements in the California halibut bottom gillnet fishery and the low annual mortality throughout California relative to the allowed Potential Biological Removal (PBR). Sea otters, while listed as threatened on the endangered species list, were not included as bycatch in the California halibut gillnet fishery because the recent gillnet depth restrictions eliminated overlap of sea otters and the gillnet fishery resulting in sea otter entanglement that is at or near zero. The lowest scoring species in the California bottom trawl fishery is the bat ray mainly due to its high inherent vulnerability and the lack of a stock assessment and reference points. The bat ray is susceptible to the fishery, but has unknown fishing mortality resulting in a moderate score. The bottom trawl fishery also experiences a wide variety of bycatch (36 groundfish species, 23 shark, skate, and ray species, and 60 other finfish and invertebrates in 2011) that occur in low numbers, are not of conservation concern, and therefore not assessed as bycatch species in this report. An exception is a large amount of unidentified jellyfish bycatch, but it also is not believed to be of conservation concern and is not included. The hook and line fishery is very species selective and while bycatch does occur no species occur in large enough numbers to be included here.





Additionally, hook and line fishermen make significant efforts to release unwanted bycatch 4

alive including releasing them without removing them from the water.

Management restrictions on gear use for the California halibut fisheries started in 1911. A stock assessment for California halibut was first published in 2011, and another is planned within the decade, with several monitoring programs underway which are used to assess the California halibut stocks. Management of all fisheries is considered moderately effective, as the fishery lacks reference points, quotas or a strategy to recover the southern stock from depleted levels, but has regulations in place that allow for at least one year of female spawning before they become susceptible to the fishery, and incorporates effective monitoring, enforcement, scientific advice and stakeholder input. Overall management of retained and discarded species is moderate the all California halibut fisheries. The trawl fishery catches a wide diversity of species but has many regulations in place to help constrain bycatch of species of concern.

Bycatch stocks that are threatened or endangered have up-to-date assessments, but several other bycatch species do not have assessments, including the white shark, which was recently considered for, but denied a threatened or endangered status in California.

Bottom trawls score the lowest since they have the stongest impact on the substrate, but are only of moderate concern as they operate predominately over soft sediment and have strong mitigation in place. However there is no evidence that an assessment of ecosystem impacts is underway. The hook and line fishery has the lowest impact on the substrate, but does not have any mitigation in place or any ecosystem based assessments in preparation. The gillnet fishery scores with the hook and line fishery based on substrate contact on soft sediments, the strong mitigation through depth restrictions and minimal mesh sizes, and that there are no ecosystem based assessments in preparation for this fishery.

5 Table of Contents Final Seafood Recommendation

Executive Summary

Introduction

Analysis

Criterion 1: Stock for which you want a recommendation

Criterion 2: Impacts on other retained and bycatch stocks

Criterion 3: Management effectiveness

Criterion 4: Impacts on the habitat and ecosystem

Acknowledgements

References

About Seafood Watch®

Guiding Principles

6 Introduction Scope of the analysis and ensuing recommendation California halibut (Paralichthys californicus) are found off the Quillayute River, Washington to southern Baja California, but are most common from Bodega Bay, California and south. This report addresses the bottom gillnet, hook and line, and bottom trawl fisheries for this species in California.

Overview of the species and management bodies

California halibut (Paralichthys californicus) inhabit waters of the eastern North Pacific from the Quillayute River, Washington to southern Baja California, but are most common from Bodega Bay, California and south {Love 1996}. They attain 1.5 m in length, 32 kg in weight and are found most commonly on soft bottoms near vertical strucuture (e.g. rocky reef) {Love 1996}. Males become sexual mature at 3 years and females at 4 {Love and Brooks 1990} {Pattison and McAllister 1990} {Kucas and Hassler 1986} and live up to 30 years {Love 1996}.

California halibut are oviparous with broadcast spawning and females may produce up to one million eggs per spawning event, but sucessful recruitment is dependent on favorable environmental conditions and the availability of suitable nursery habitat {CalCOFI 2012}.

Three gear types fish commercially for California halibut: bottom trawl, hook and line, and bottom gillnet. Both bottom trawl and hook and line are operated throughout California (mainly south of Bodega Bay), while bottom gillnet operates south of Point Conception {CalCOFI 2012}. Recreational fishing, which will not be addressed in this report, is conducted with hook and line only. The California Department of Fish and Wildlife (CDFW) manages the California halibut fisheries, except the limited entry (LE) California halibut bottom trawl fishery, which is subject to the federally managed Shorebased Individual Fishing Quota (IFQ) Fishery. The management of the California halibut fisheries has been evolving since the early 1900s {CDFG 2011a}. Today neither bottom trawling (except in the California Halibut Trawl Grounds (CHTG)) nor gillnets are legal in state waters (0-3 nm from shore) and both require limited entry permits (except fishing in the CHTG (Figure 1), which requires a state permit) {CalCOFI 2012} {CDFG 2008} {CDFG 2011a}. Trawl gear has been the dominate gear used recently due to increased gillnet restrictions and accounted for 49% of the total catch in 2011, while hook and line accounted for 29% and gillnet accounted for 21% {CalCOFI 2012}.

7 Figure 1. Map of the area within state waters where trawling is legal, aka California halibut trawl grounds (CHTG). Adapted from CDFG 2008.

Production Statistics Total California halibut landings were 199.7 t in 2011, with 98.8 t from bottom trawls, 58.7 t from hook and line, and 41.6 t from gillnets {CalCOFI 2012}. It is estimated that 117 t of California halibut were caught recreationally (mainly hook and line) in 2011 {CalCOFI 2012}. The coast of California and Baja California are the only locations of California halibut production worldwide. In 2005, artisanal fishers around La Paz Bay, Mexico caught approximately 16 t of California halibut, but production from Mexico is otherwise unknown. Overall production has decreased over time (Figure 2) and changed from gillnet dominated to bottom trawl dominated (Figure 3). Commercial catch peaked in the 1910s, and 1940s especially south of Point Conception (Figure 2).

8 Figure 2. Commercial catch (metric tons) from 1915 to 2010 north and south of Point Conception.

Adapted from CDFG 2011a.

Figure 3. Commercial catch of California halibut by gear type from 1981-2011.

Adapted from CalCOFI 2012.

Importance to the US/North American market

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Common and market names The common name is California halibut. The market name is Halibut and other vernacular names include bastard halibut and Monterey halibut {Love 1996} {FDA 2012}.

Primary product forms

–  –  –

Analysis Scoring Guide

• All scores result in a zero to five final score for the criterion and the overall final rank. A zero score indicates poor performance, while a score of five indicates high performance.

• The full Seafood Watch Fisheries Criteria that the following scores relate to are available on our website at http://www.seafoodwatch.org Criterion 1: Stock for which you want a recommendation This criterion evaluates the impact of fishing mortality on the species, given its current abundance. The inherent vulnerability to fishing rating influences how abundance is scored, when abundance is unknown. The final Criterion 1 Score is determined by taking the geometric mean of the abundance and fishing mortality scores.

Summary

–  –  –

Justification of Ranking

CALIFORNIA HALIBUT: CENTRAL CALIFORNIA

Factor 1.1 - Inherent Vulnerability to Fishing

• Low = FishBase vulnerability score for species 0-35 OR species exhibits life history characteristics that make it resilient to fishing, e.g., early maturing (5 years), short lived ( 10 years), small maximum size, and low on food chain.

• Medium = FishBase vulnerability score for species 36-55 OR life history characteristics that make it neither particularly vulnerable or resilient to fishing, e.g. moderate age at sexual maturity (5-15 years), moderate maximum age (10-25 years), moderate maximum size, and middle of food chain.

• High = FishBase vulnerability score for species 56-100 OR life history characteristics that make is particularly vulnerable to fishing, e.g. long-lived (25 years), late maturing (15 years), low reproduction rate, large body size, and top-predator.

Note: The FishBase vulnerability scores is an index of the inherent vulnerability of marine fishes to fishing based on life history parameters: maximum length, age at first maturity, longevity, growth rate, natural mortality rate, fecundity, spatial behaviors (e.g. schooling, aggregating for breeding, or consistently returning to the same sites for feeding or reproduction) and geographic range.

California: Central Northeast Pacific, Hook/line California: Central Northeast Pacific, Trawl, Bottom

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