Jumbo squid Dosidicus gigas - The Safina Center

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Jumbo squid Dosidicus gigas - The Safina Center
Jumbo squid
                                               Dosidicus gigas

                               Image ©Scandinavian Fishing Yearbook/ www.scandfish.com

                                                Chile, Peru
                                                         Jig

                                                December 3, 2015

                                 Max McClure, Independent Research Analyst

Disclaimer: Seafood Watch® strives to have all Seafood Reports reviewed for accuracy and completeness by
external scientists with expertise in ecology, fisheries science and 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.
Jumbo squid Dosidicus gigas - The Safina Center
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About Seafood Watch®
Monterey Bay Aquarium’s Seafood Watch® program evaluates the ecological sustainability of
wild-caught and farmed seafood commonly found in the United States marketplace. Seafood
Watch® defines sustainable seafood as originating from sources, whether wild-caught or
farmed, which can maintain or increase production in the long-term without jeopardizing the
structure or function of affected ecosystems. Seafood Watch® makes its science-based
recommendations available to the public in the form of regional pocket guides that can be
downloaded from www.seafoodwatch.org. The program’s goals are to raise awareness of
important ocean conservation issues and empower seafood consumers and businesses to make
choices for healthy oceans.

Each sustainability recommendation on the regional pocket guides is supported by a Seafood
Report. Each report synthesizes and analyzes the most current ecological, fisheries and
ecosystem science on a species, then evaluates this information against the program’s
conservation ethic to arrive at a recommendation of “Best Choices,” “Good Alternatives” or
“Avoid.” The detailed evaluation methodology is available upon request. In producing the
Seafood Reports, Seafood Watch® seeks out research published in academic, peer-reviewed
journals whenever possible. Other sources of information include government technical
publications, fishery management plans and supporting documents, and other scientific reviews
of ecological sustainability. Seafood Watch® Research Analysts also communicate regularly
with ecologists, fisheries and aquaculture scientists, and members of industry and conservation
organizations when evaluating fisheries and aquaculture practices. Capture fisheries and
aquaculture practices are highly dynamic; as the scientific information on each species changes,
Seafood Watch’s sustainability recommendations and the underlying Seafood Reports will be
updated to reflect these changes.

Parties interested in capture fisheries, aquaculture practices and the sustainability of ocean
ecosystems are welcome to use Seafood Reports in any way they find useful. For more
information about Seafood Watch® and Seafood Reports, please contact the Seafood Watch®
program at Monterey Bay Aquarium by calling 1-877-229-9990.
Jumbo squid Dosidicus gigas - The Safina Center
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Guiding Principles
Seafood Watch defines sustainable seafood as originating from sources, whether fished 1 or
farmed, that can maintain or increase production in the long-term without jeopardizing the
structure or function of affected ecosystems.

Based on this principle, Seafood Watch had developed four sustainability criteria for evaluating
wild-catch fisheries for consumers and businesses. These criteria are:
    • How does fishing affect the species under assessment?
    • How does the fishing affect other, target and non-target species?
    • How effective is the fishery’s management?
    • How does the fishing affect habitats and the stability of the ecosystem?

Each criterion includes:
   • Factors to evaluate and score
   • Guidelines for integrating these factors to produce a numerical score and rating

Once a rating has been assigned to each criterion, we develop an overall recommendation.
Criteria ratings and the overall recommendation are color coded to correspond to the
categories on the Seafood Watch pocket guide and the Safina Center’s online guide:

Best Choice/Green: Are well managed and caught in ways that cause little harm to habitats or
other wildlife.

Good Alternative/Yellow: Buy, but be aware there are concerns with how they’re caught.

Avoid/Red: Take a pass on these for now. These items are overfished or caught in ways that
harm other marine life or the environment.
ry scored as a Very High Concern for either factor under Management (Criterion 3).

   1 “Fish” is used throughout this document to refer to finfish, shellfish and other invertebrates.
Jumbo squid Dosidicus gigas - The Safina Center
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Summary
This report provides recommendations for the South American stock of Humboldt squid (Dosidicus
gigas). The analysis only includes the Chilean and Peruvian fisheries. In Chile, the majority of the stock is
reserved for artisanal fishermen, with jigging (with or without lights) as the primary method in most
regions. In Peru, the stock is almost exclusively exploited by artisanal light jiggers. Artisanal jigging is
therefore the only gear reviewed in this report. A number of other nations, most notably China, exploit
the same D. gigas stock on the high seas, thus affecting the assessment.

D. gigas has low inherent vulnerability, but its abundance is highly variable and appears linked to
environmental conditions. The stock is not considered depleted and fishing effort in Chile and Peru does
not exceed recommended levels. The unavailability of Chinese fishing statistics makes true fishing
mortality difficult to evaluate.

Discard rates and bycatch information for the fishery are not available, but jigging with or without lights
(the most common gear type used in the Chilean and Peruvian artisanal fisheries) is highly selective for
squid. Less selective gears, including trawling, contribute negligibly to U.S. imports.

Management of the stock is moderately effective, but both Chile and Peru lack biological control points
and accurate biomass predictions. Chile lacks explicit limits on license holders and quantitative
population assessment, while Peru has more direct and regular methods of biomass evaluation. The
Chinese effect on stock is not monitored.

Scientific advice is largely followed in both countries, and enforcement has been effective, although
Chilean in-person monitoring of the artisanal fishery is limited. The fishery is too recent to have a clear
track record. Artisanal fishers have official recognition in both countries, but are not fully included in
management decisions.

Jigging has minimal impact on marine ecosystems, while the ecological role of D. gigas and the potential
effects of its depletion are poorly understood.

Both the Chilean and the Peruvian fisheries are ranked as Good Alternatives.

Table of Conservation Concerns and Overall Recommendations

Stock / Fishery               Impacts on    Impacts on Management Habitat and Overall
                              the Stock     other Spp.              Ecosystem Recommendation
Jumbo squid                   Yellow        Green (5.00) Red (2.00) Green (3.87) Good Alternative
Chile Southeast Pacific - Jig (2.64)                                             (3.181)
Jumbo squid                   Yellow        Green (5.00) Red (2.00) Green (3.87) Good Alternative
Peru Southeast Pacific - Jig (2.64)                                              (3.181)
Jumbo squid Dosidicus gigas - The Safina Center
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Scoring Guide

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/Green = Final Score >3.2, and no Red Criteria, and no Critical scores

•   Good Alternative/Yellow = Final score >2.2-3.2, and neither Harvest Strategy (Factor 3.1)
    nor Bycatch Management Strategy (Factor 3.2) are Very High Concern 2, and no more than
    one Red Criterion, and no Critical scores
•   Avoid/Red = Final Score
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Table of Contents
About Seafood Watch® ................................................................................................................................. 2

Guiding Principles ......................................................................................................................................... 3

Summary ....................................................................................................................................................... 4

Introduction .................................................................................................................................................. 7

Assessment ................................................................................................................................................. 14
   Criterion 1: Stock for which you want a recommendation..................................................................... 14
   Criterion 2: Impacts on Other Species .................................................................................................... 18
   Criterion 3: Management effectiveness ................................................................................................. 20
   Criterion 4: Impacts on the habitat and ecosystem................................................................................ 29

Acknowledgements..................................................................................................................................... 33

References .................................................................................................................................................. 34
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Introduction
Scope of the analysis and ensuing recommendation

This report provides recommendations for the South American stock of Humboldt squid (Dosidicus
gigas), a major commercially imported squid species in the United States. The analysis only includes the
Chilean and Peruvian Humboldt squid fisheries. In Chile, the majority of the stock is reserved for
artisanal fishermen, with jigging (with or without lights) as the primary method in most regions. In Peru,
the stock is almost exclusively exploited by artisanal light jiggers.

Overview of the species and management bodies

Dosidicus gigas is an ommastrephid squid, subfamily Ommastrephinae. The species is restricted to the
Eastern Pacific, historically ranging between subtropical North and South America with temporary
excursions to the north and south (Nigmatullin, et al. 2001). In the past few decades, it has also become
a common presence off the coast of southern Chile and the West Coast of the United States, extending
as far north as Alaska (Keyl et al. 2008) (Zeidberg and Robison 2007). The species is capable of traveling
≈30 km/day and undergoes daily vertical migrations, spending the day below 250 m and ascending
nearly to the surface at dusk, while periodically diving below 300 m (Gilly et al 2006).

As with other ommastrephids, D. gigas has a lifespan of 1–2 years (Argüelles, et al. 2001). Rapidly
reaching mantle lengths of 1.2 m and weights of 50 kg, it is the largest nektonic squid, though individuals
vary in size (Nigmatullin, et al. 2001). The species is semelparous and highly fertile, with year-round
reproduction typically producing two cohorts a year (autumn/winter and spring/summer hatchings)
(Argüelles, et al 2001), but little else is known about its reproductive biology. Environmental conditions
appear to have a large influence on recruitment (Rodhouse 2001).

D. gigas feeds on a variety of small pelagic and demersal fishes, crustaceans, and squids, and in some
cases also targeting larger, economically important species such as hake (Alarcón-Muñoz, et al. 2008)
(Field, et al. 2007) (Markaida and Sosa-Nishizaki 2003). Primary predators are tuna, billfish, sharks,
pinnipeds, and toothed whales (Nigmatullin, et al. 2001) (Field, et al. 2007). Cannibalism is widely
observed but likely overreported (Ibáñez, et al. 2008).

Globally, D. gigas constitutes the world’s largest cephalopod fishery (FAO 2014), supporting major
fisheries off the coast of Chile and Peru and in the Gulf of California, an occasional fishery off the Costa
Rica dome, and a sport fishery on the West Coast of the United States. The North and South American
stocks constitute genetically distinct subpopulations (Sandoval-Castellanos et al. 2007) (Staaf, et al.
2010). Squid caught in Peruvian and Chilean waters are not genetically differentiable (Ibáñez et al.
2011).

Chilean management

As of 2012, Chile was the world’s eighth-largest fishing nation (FAO 2014). Fisheries are under the aegis
of the Ley General de Pesca y Acuicultura, adopted in 1989 and most recently updated in 2013
(Subpesca 2014d). The executive policymaking branch of Chilean fisheries governance is Subpesca,
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under the Ministry of Economy, Development and Reconstruction, which incorporates national, zonal,
and regional fisheries councils. The separate Sernapesca acts as a control and enforcement body. The
Instituto de Fomento Pesquero (IFOP) is a nonprofit corporation, founded both by the Ministry and by
the private sector organization Sonapesca, which provides fisheries analysis. The Fondo de Investigación
Pesquero (FIP), under the umbrella of Subpesca, also funds fisheries research.

Chilean fishery managers make use of quotas (global, individual, and, in some cases, individual
transferable), gear restrictions, seasonal/area closures, establishment of bycatch limits, and size
limitations. Regular stock assessments are conducted and management measures set in place by
Subpesca according to recommendations made by IFOP and the regional scientific committees. Artisanal
fishers have formal recognition: all are officially registered by Sernapesca, are apportioned separate
quotas, and have exclusive access to the 5 miles adjacent to the coastline. Chile is a signatory to most
major international treaties and a member of the South Pacific Regional Fisheries Management
Organisation (SPRFMO) (FAO 2010b) (OECD 2009).

Recent overexploitation in multiple fisheries and weak monitoring of bycatch, discards, and unreported
fishing (OECD 2009) (Perez 2005) are beginning to be addressed by stricter scientific monitoring, as
required by Ley 20.625. Vessel monitoring systems are currently mandatory on all large-scale fishing
vessels (FAO 2010) (FAO 2010b).

Peruvian management

As of 2012, Peru was the world’s fourth-largest fishing nation (FAO, 2014). Fisheries are governed by the
General Law on Fisheries (Decreto No. 25977) and managed by the office of the Deputy Minister of
Fisheries, a branch of the Ministry of Production (PRODUCE). The Minister is responsible for developing
and managing national fisheries policies, and oversees the Instituto del Mar del Perú (IMARPE), which
conducts fisheries research, and the Fondo Nacional de Desarrollo Pesquero (FONDEPES), which is
responsible for developing artisanal fisheries (FAO, 2010a).

Peruvian fishery managers make use of seasonal/area closures, reductions in the permitted fishing fleet,
size limitations, gear restrictions, and establishment of bycatch limits. Regular stock assessments are
conducted and management measures set in place by the Minister according to recommendations made
by IMARPE and its regional branches. IMARPE has a well-established onboard observer program to
monitor discards and bycatch (PRODUCE 2012a). Peru is a signatory to most major treaties and a
cooperating non-member of the SPRFMO.

Production Statistics

Dosidicus gigas capture has expanded dramatically in recent years, due both to increased fishing effort
and to the species’ population growth and range expansion, potentially tied to climate change and/or
the decline of finfish competitors (Gilly, et al. 2013) (Keyl et al., 2008) (Zeidberg & Robison, 2007). Based
on catch data from the FAO’s FishStatJ, the recent catch primarily derives from Peru, China, and Chile,
with negligible captures by other nations.
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Fishery in Chilean waters

Humboldt squid have been caught incidentally off the Chilean coast since at least 1957, and were caught
sporadically at low levels until the 1990s (Rocha & Vega, 2003). The Chilean artisanal jig fishery was
initially centered in Coquimbo (Region IV), beginning in the late 1990s or early 2000s (Cortés, 2012)
(pers. comm., Patricio Galvez, IFOP2015), and slowly expanded into Regions V and VIII after the 2002
spike in squid landings (Keyl et al., 2008) (Subpesca, 2012a). Primary fishing grounds are nearshore
between 36°–38.5°S and 29°–34°S. Japanese, Korean, and Chinese vessels also operate in international
waters off the Chilean coast (Arkhipkin, et al. 2015).

Purse seining remains popular in the Region VIII artisanal fishery, but is likely a minor contributor
(Arancibia et al., 2007) (pers. comm., Patricio Galvez) (pers. comm., Pablo Lizana, SeaTec). Artisanal
fishers also conducted trawls until gear used in the fishery was regulated in 2013 (pers. comm., Liesbeth
van der Meer).

Although industrial hake trawlers had opportunistically pursued squid in the past, the directed industrial
trawl fishery began in 2011, with the first global quota established in 2012 (Subpesca, 2012a). These
efforts are primarily focused in the south (Regions VIII–XII), and constitute midwater trawls conducted in
short trips with low storage volumes (pers. comm., Patricio Galvez) (pers. comm., Pablo Lizana).

Currently (for the period 2014–2019), 80% of the global quota is reserved for the artisanal fleet
(Subpesca 2013a) (Subpesca 2014b). According to landings by sector reported to Sernapesca in previous
years, artisanal catch has exceeded 80% of the total for every year since 2001 except 2007 (when
artisanal catch constituted 67% of the total) and 2010 (33% of total) (Subpesca 2012a, Sernapesca
2014).

Figure 1. Humboldt squid capture in Chile by sector (Subpesca 2012a, Sernapesca 2014).
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Fishery in Peruvian waters

USSR trawlers reported Humboldt squid as bycatch off the coast of Peru in the late 1980s, but the
species was of low economic importance until the industrial fishery, comprised of Japanese and Korean
mechanized jigging fleets, began in 1991 (IMARPE, 1996). Japanese and Korean ships have since
operated continuously in the Peruvian EEZ from 3–7°S (Waluda, et al. 2006), except for 1996
(Mariátegui, et al. 1997). Japanese, Korean, and Chinese vessels also operate in international waters off
the Peruvian coast (Arkhipkin, et al. 2015).

Catches by the Peruvian artisanal fleet, which is active primarily in the southern half of the country,
were not significant before 1996 (Estrella Arellano & Swartzman, 2010). The number of artisanal jigging
vessels has increased since 1998, exceeding 4,000 in 1998, while the number of participating industrial
vessels has concurrently decreased. The artisanal fleet has taken approximately 90% of the catch from
2004–2012 (Arkhipkin, et al. 2015).

While the IMARPE webpage on Humboldt squid describes the artisanal fishery as using both gill nets and
hand-line jigging (IMARPE, 2008), Estrella Arellano & Swartzman found that 97% of catches from 1996–
2006 came from jigging with lights (Estrella Arellano & Swartzman, 2010).

Figure 2. Humboldt squid capture in Peru by sector (sector-specific fishing data unavailable prior to 2002) (IMARPE
1995, 2001, 2005, 2009, 2010, 2013).
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Other

A number of other nations exploit South American D. gigas stock. Japanese and Korean fleets are
permitted to fish within Peruvian waters. Taiwan has also operated a smaller high-seas mechanized
jigging fleet in the southeast Pacific since 2002 (SPRFMO 2013a), with an average annual catch around
21,000 tonnes (Arkhipkin, et al. 2015). Ecuador’s official D. gigas fishery was authorized in 2014,
allowing for 30 artisanal and 6 industrial vessels (Subsecretario de Recursos Pesqueros 2014).

Most prominently, the Chinese distant-water mechanized jigging fleet, redistributing after declines in
Illex argentinus stock, has been operating outside the Chilean and Peruvian EEZs from 7–20°S since 2001
(Chen, et al 2008). From 2005–2010, the Chinese catch stayed below 140,000 tonnes, increasing to
220,000–250,000 tonnes in 2011 and 2012 (Arkhipkin, et al. 2015).

Figure 3. Humboldt squid capture in the South Pacific and Central Eastern Pacific by fishing nation (FAO 2014b).

Importance to the U.S./North American market

Complete data on Humboldt squid imports into the U.S. are not available: the National Marine Fisheries
Service (NMFS) identifies commercial U.S. squid imports as either “Loligo NSPF” or “squid NSPF,” where
NSPF stands for “not specifically provided for.”
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According to NMFS data, “squid NSPF” imports are overwhelmingly Chinese in origin. But China’s fishing
statistics are complicated by historical underreporting of catches in its distant-water fleet (Pauly et al.,
2013) and the failure to distinguish D. gigas captures from often significant catches of other squids.
Chinese trade statistics are similarly complicated by the importation, processing, and re-exports of other
squid species (see Seafood Watch report on California market squid). This report will not evaluate the
Chinese Humboldt squid fishery.

According to Chilean customs statistics, approximately 80% of Humboldt squid exported from Chile in
2013 was shipped by SeaTec. Owner Pablo Lizana states that SeaTec exclusively buys from artisanal
suppliers because industrially trawled squid are of lower quality (pers. comm., Pablo Lizana, SeaTec
Chile; see Chilean customs data provided by Lizana under his name in bibliography). Damage to squid
skin and mantle during trawls generally leads to reduced value for trawled catches (Arkhipkin et al.,
2015).

Figure 4. U.S. imports of “Squid NSPF” (squid of unspecified species) by exporting nation (NMFS 2014).
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Common and market names

Humboldt squid, jumbo squid, jumbo flying squid, calamar gigante, pota (Peru), jibia (Chile). May also be
sold in the U.S. simply as squid or calamari.

Primary product forms

The majority of squid products for human consumption are imported frozen, either whole or in fillets or
rings. Humboldt squid is also sold boiled, pickled, as jerky (or “sakiika”), salted and fermented
(“shiokara”), and mixed with other seafood, although these forms are less common in North American
markets.
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Assessment
This section assesses the sustainability of the fishery(s) relative to the Seafood Watch Criteria
for Fisheries, available 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. The Criterion 1 rating is determined as
follows:

•   Score >3.2=Green or Low Concern
•   Score >2.2 and
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•   High—The FishBase vulnerability score for species is 56-100, OR species exhibits 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.

Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Low

Average age at maturity: < 1 year (Seafood Watch score: 3)
Average maximum age: 1–2 years (Seafood Watch score: 3)
Reproductive strategy: pelagic egg mass (Seafood Watch score: 2)
Density dependence: no compensatory or depensatory dynamics at low population density (Seafood
Watch score: 2)
Mean score: 2.5 = low inherent vulnerability

Rationale:
Dosidicus gigas is short-lived and semelparous (i.e., reproduces only once before death) (Nigmatullin et
al. 2001). Both its potential fecundity and its pelagic egg masses are the largest among the
cephalopods (Nigmatullin and Markaida 2008) (Staaf, et al. 2008), but little else is known about its
reproductive biology. The species’ labile population dynamics are likely more dependent on
environmental variability than population density (Pierce and Guerra 1994) (Rodhouse 2001), with the El
Niño Southern Oscillation (ENSO) acting as a particularly strong influence (Morales-Bojórquez et al.
2001) (Waluda et al. 2006).

Factor 1.2 - Stock Status

Scoring Guidelines

•   5 (Very Low Concern)—Strong evidence exists that the population is above target
    abundance level (e.g., biomass at maximum sustainable yield, BMSY) or near virgin biomass.
•   4 (Low Concern)—Population may be below target abundance level, but it is considered not
    overfished
•   3 (Moderate Concern) —Abundance level is unknown and the species has a low or medium
    inherent vulnerability to fishing.
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•   2 (High Concern)—Population is overfished, depleted, or a species of concern, OR abundance
    is unknown and the species has a high inherent vulnerability to fishing.
•   1 (Very High Concern)—Population is listed as threatened or endangered.
Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Moderate Concern

Information is generally unavailable about the stock status of Dosidicus gigas off the coast of South
America. IMARPE evaluates biomass off the coast of Peru with hydroacoustic methods (Argüelles and
Tafur 2010), with values ranging between 2.51 and 2.96 mt for the period 2001–2011 (Arkhipken, et al.
2015). Estimates of Chilean biomass have been made using both hydroacoustic surveys (ranging
between ≈40,400 and ≈682,600 within the period 2001–2006) (Alarcón-Muñoz, et al. 2008) and Ecopath
modeling (≈400,000 tonnes in 2005) (Arancibia and Neira 2008). But the accuracy of these methods in
the case of D. gigas is unclear (Morales-Bojórquez, et al. 2001). Abundance has been highly variable, and
recruitment appears to be linked to environmental conditions. Chile’s Subpesca has declined to define
biological reference points with respect to the Humboldt Current population (CCT-RDZCS 2013) (CCT-
RDZCS 2014), and current reference points and biomass estimates from IMARPE are not available.

Factor 1.3 - Fishing Mortality

Scoring Guidelines

•   5 (Very Low Concern)—Highly likely that fishing mortality is below a sustainable level (e.g.,
    below fishing mortality at maximum sustainable yield, FMSY), OR fishery does not target
    species and its contribution to the mortality of species is negligible (≤ 5% of a sustainable
    level of fishing mortality).
•   3.67 (Low Concern)—Probable (>50%) chance that fishing mortality is at or below a
    sustainable level, but some uncertainty exists, OR fishery does not target species and does
    not adversely affect species, but its contribution to mortality is not negligible, OR fishing
    mortality is unknown, but the population is healthy and the species has a low susceptibility
    to the fishery (low chance of being caught).
•   2.33 (Moderate Concern)—Fishing mortality is fluctuating around sustainable levels, OR
    fishing mortality is unknown and species has a moderate-high susceptibility to the fishery
    and, if species is depleted, reasonable management is in place.
•   1 (High Concern)—Overfishing is occurring, but management is in place to curtail
    overfishing, OR fishing mortality is unknown, species is depleted, and no management is in
    place.
17

•   0 (Critical)—Overfishing is known to be occurring and no reasonable management is in place
    to curtail overfishing.
Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Moderate Concern

Humboldt squid is the target of the largest global invertebrate fishery in the world by volume (Rosa, R et
al. 2013). Global catches have increased from 210,000 mt in 2000 to 847,000 mt in 2013, with the
highest catch (950,000 mt) in 2012 (FAO 2014b). In 2013, 847,292 mt were caught; all but 11,132 mt off
Chile and Peru (the remainder was caught by Mexico) (FAO 2014b). Of this 836,160 mt, approximately
54% (over 450,000 mt) was caught by Peru and nearly 13% (106,271 mt) by Chile. Virtually all of the
remaining 32% (264,000 mt) was caught by China (FAO 2014b).

Chile and Peru both conduct assessments of the stock (see Detailed Rationale below), but China does
not. Thus, there is no way of knowing whether total mortality is sustainable, leading to a score of
“moderate” concern for this factor.

Rationale:
The agency currently uses historical yields to calculate maximum constant yield (MCY) and assign a
global quota or total allowable catch (TAC) for the species across all fishery regions (Subpesca 2012a).
Catch has stayed well below this MCY for both 2012 and 2013 (Sernapesca 2014). Subpesca has since
commissioned a study to evaluate new management methods (see Proyecto 2013-18 in (FIP 2013)).
Fisheries documents refer to the stock as “fully exploited” (Subpesca 2014a). IMARPE sets an initial
global quota at less than 2/3 MSY, which is then altered over the course of the season in accordance
with midseason biomass estimates. Catch has stayed below or at the recommended catch from 2008–
2012 with the exception of 2009, when total allowable catch, but not FMSY, was exceeded (Argüelles
2012) (Carbajal-Villalta 2009) (IMARPE 2010) (PRODUCE 2012b). PRODUCE described the stock as
underexploited in its last publicly available statement on the fishery (PRODUCE 2012b).

See Factor 3.1, Harvest Strategy, for details on the definition of MCY.
18

Criterion 2: Impacts on Other Species
All main retained and bycatch species in the fishery are evaluated in the same way as the
species under assessment were evaluated in Criterion 1. Seafood Watch® defines bycatch as all
fisheries-related mortality or injury to species other than the retained catch. Examples include
discards, endangered or threatened species catch, and ghost fishing. To determine the final
Criterion 2 score, the score for the lowest scoring retained/bycatch species is multiplied by the
discard rate score (ranges from 0-1), which evaluates the amount of non-retained catch
(discards) and bait use relative to the retained catch. The Criterion 2 rating is determined as
follows:

•   Score >3.2=Green or Low Concern
•   Score >2.2 and
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Criterion 2 Assessment

Factor 2.4–Discard Rate

Chile/Southeast Pacific, Jig

< 20%

Discard rates are largely unavailable, but jig fisheries are typically highly selective (Boyle and Rodhouse
2005), with a discard rate of 0.1% (Kelleher 2005).

Rationale
In accordance with its 2012 fisheries discards law, Chile is currently introducing an onboard observer
program in its industrial fisheries (Cocas 2014)(Subpesca 2012d), with the D. gigas trawl fishery to be
included within the next two years (Patricio Galvez, IFOP, pers comm).

Factor 2.4–Discard Rate

Peru/Southeast Pacific, Jig

< 20%

Discard rates are largely unavailable, but jig fisheries are typically highly selective (Boyle and Rodhouse
2005), with a discard rate of 0.1% (Kelleher 2005).

Rationale
In Peru, IMARPE places scientific observers aboard foreign industrial squid jiggers within its EEZ
(PRODUCE 2011), but artisanal landings are evaluated at port (IMARPE 2013a).
20

Criterion 3: Management effectiveness
Management is separated into management of retained species (harvest strategy) and
management of non-retained species (bycatch strategy).

The final score for this criterion is the geometric mean of the two scores. The Criterion 3 rating is
determined as follows:

•   Score >3.2=Green or Low Concern
•   Score >2.2 and
21

•   1 (Very High Concern)—Management exists, but Management Strategy and/or Recovery of
    Species of Concern rated ‘ineffective.’
•   0 (Critical)—No management exists when there is a clear need for management (i.e., fishery
    catches threatened, endangered, or high concern species), OR there is a high level of Illegal,
    unregulated, and unreported fishing occurring.

Factor 3.1 Summary

Factor 3.1: Management of fishing impacts on retained species
Region / Method         Strategy Recovery Research Advice          Enforce    Track      Inclusion
Chile Southeast Pacific Moderately N/A      Ineffective Moderately Moderately Moderately Moderately
Jig                     Effective                       Effective Effective Effective Effective
Peru Southeast Pacific Moderately N/A       Ineffective Highly     Highly     Moderately Moderately
Jig                     Effective                       Effective Effective Effective Effective

Subfactor 3.1.1 – Management Strategy and Implementation

Considerations: What type of management measures are in place? Are there appropriate
management goals, and is there evidence that management goals are being met? To achieve a
highly effective rating, there must be appropriate management goals, and evidence that the
measures in place have been successful at maintaining/rebuilding species.

Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Moderately Effective

Chile and Peru are both deemed to have moderately effective management strategies and
implementation programs. Both catch Humboldt squid only within their EEZs, and both have
implemented management measures since 2012 (see below). The effectiveness of each country’s
strategy is as yet untested (given that each has only been in place for a few fishing seasons), but both
policies still have weaknesses in terms of regulation during years of low abundance (i.e., they do not
define a minimum biomass below which fishing should not occur) and the ability to estimate each year’s
exploitable biomass through annual pre-fishing season surveys (as strongly recommended for
cephalopod fisheries by researchers, e.g., (Rodhouse et al. 2014)). Furthermore, the overall
management strategies are weakened by the considerable catch made by China (especially) on the high
seas.

Chile
Management of the squid fishery in Chile started in 2012. Fisheries legislation demonstrates concern for
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scientific advice and the precautionary principle: legislation specifically cites input of local scientific
committees, and the squid fishery has recently been closed to new permitholders because the resource
is no longer deemed underexploited (Subpesca 2014e). But there are no explicit limits on the number of
artisanal permitholders (Subpesca 2013a). No reference points have been developed for the fishery, so
Subpesca currently sets the fishery’s modifiable TAC using a maximum constant yield based on the
historical catch from 2004–2010 (Subpesca 2013a).

Peru

IMARPE estimates an initial MSY using historic CPUE/landings data and adjusts according to direct
hydroacoustic stock assessments. This MSY is used to generate a global quota at < 2/3 of MSY
(PRODUCE 2012d). Production statistics for the artisanal fishery are collected by dockside observers and
reported to PRODUCE, while the foreign industrial fleet is monitored by onboard observers and vessel
monitoring systems. A permit is required to participate in the fishery.

Rationale:

Chile

The 2012 TAC, which has set the template for the following years’ quotas, analyzes the annual catch
from 2004–2010 using Annala’s maximum constant yield method: MCY = cYav (cited in Subpesca, 2012a
as (Francis 1992)), where Yav is the average catch over a period of time, and c is the natural variability in
the biomass of the stock. For 2012, Yav over the period of interest equalled ≈167,000 tonnes. Subpesca
assigned c a value near or equal to 1 based on D. gigas’ presumed “resilience and productivity,”
resulting in the highest possible calculated MCY. Additionally, the final TAC was set at 200,000 tonnes,
above this MCY, on the assumption that the stock was underexploited. Of this quota, 4,000 tonnes are
reserved for research. Of the remaining 196,000, 80% is reserved for artisanal fishers and 20% for
industrial vessels. In the artisanal sector, an additional percentage can be captured as bycatch in other
fisheries. Although this fractioning plan was suspended in 2014 (Subpesca 2014c), it has been
reapproved for the years 2014–2019 (Subpesca 2014b). Fisheries legislation demonstrates concern for
scientific advice and the precautionary principle: legislation specifically cites input of local scientific
committees, and the squid fishery has recently been closed to new permitholders because the resource
is no longer deemed underexploited (Subpesca 2014e). But there are no explicit limits on the number of
artisanal permitholders (Subpesca 2013a), and Chile has been criticized for its historic response to
overfishing and environmental change (Kalikoski, et al. 2006b). Reported catch has never exceeded the
TAC (Sernapesca 2014). The lack of abundance data suggests that the quota, set above the perceived
capacity of the artisanal fleet in 2012, is likely to increase as the artisanal fleet expands (pers. comm.,
Liesbeth van der Meer, Oceana Chile 2015). Overlap of the Chilean stock with that pursued by the
(primarily Chinese) high-seas fishery in the same region complicates stock assessment and management.
Resource management consulting firm MRAG suggests that Chinese high seas jiggers may be taking
7,000 tonnes of squid a month (MRAG 2005)). Catch from vessels that operate in international waters is
not included in Chile’s TAC.
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Peru

Since 2010, the MSY has been calculated using the Schaefer Biomass Dynamic Model, with the
assumption that catch varies with sea surface temperature (Argüelles 2012) (for D. gigas population
parameters from the Schaefer model, see Arkhipkin, et al. 2015). MSY from 2001–2011 has been
estimated at around 991,514 tonnes. In 2012, this MSY was calculated as 854,859 tonnes, which led to
the establishment of a global quota of 500,000 tonnes (PRODUCE 2012d). This quota may be adjusted
over the course of the season based on monthly fisheries reports and midseason hydroacoustic surveys
(IMARPE 2013b). Earlier in the fishery’s history, global quotas were set using CPUE values from 1991–
1998 and hydroacoustic surveys from 1999–2009, coupled with Schaefer and Fox production models
(Arkhipkin, et al. 2015).

Fisheries legislation demonstrates concern for scientific advice and the precautionary principle: the Ley
General de la Pesca specifically requires that IMARPE recommend annual quotas for stocks and conduct
research to validate its recommendations (PRODUCE 2014). There has been criticism of Peru’s
historically slow response to overfishing, but praise for management’s response to environmental
change (notably, IMARPE explicitly includes sea-surface temperature monitoring when evaluating the
squid fishery) (Kalikoski, et al. 2006a) (Argüelles 2012). There are no explicit limits on the number of
artisanal permitholders, and the TAC has been exceeded once, in 2009 (IMARPE 2010). If established
quotas are exceeded in the course of the season, the Ley General de la Pesca requires that all
“extractive activities” be suspended (PRODUCE 2014).

Overlap of stock with the squid pursued by the (primarily Chinese) high-seas fishery in the same region
complicates stock assessment and management (MRAG suggests that Chinese high seas jiggers may be
taking 7,000 tonnes of squid a month (MRAG 2005)). Catch from vessels that operate in international
waters is not included in Peru’s TAC.

Subfactor 3.1.2 – Recovery of Species of Concern

Considerations: When needed, are recovery strategies/management measures in place to
rebuild overfished/threatened/ endangered species or to limit fishery’s impact on these species
and what is their likelihood of success? To achieve a rating of Highly Effective, rebuilding
strategies that have a high likelihood of success in an appropriate timeframe must be in place
when needed, as well as measures to minimize mortality for any
overfished/threatened/endangered species.

Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig
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N/A

Jumbo squid are the only main species landed (or even caught) in the fishery and are not thought to
have been overfished historically.

Subfactor 3.1.3 – Scientific Research and Monitoring

Considerations: How much and what types of data are collected to evaluate the health of the
population and the fishery’s impact on the species? To achieve a Highly Effective rating,
population assessments must be conducted regularly and they must be robust enough to
reliably determine the population status.

Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Ineffective

Scientific research and monitoring is scored “ineffective” for the Humboldt squid fishery because there
is no monitoring or research conducted on the component on the high seas fished by China (which
accounted for about 1/3 of the catch in 2013 (FAO 2014b)). This is unfortunate, because Chile and
especially Peru do have some research and monitoring measures in place. It is unclear whether these
measures include pre-season surveys as recommended by scientists (e.g., (Rodhouse et al 2014)).

Chile
Although IFOP has begun or is planning to conduct studies on assessment of D. gigas stock, assessments
have thus far been sporadic and incomplete. Methods used include hydroacoustic surveys (Alarcón-
Muñoz, et al. 2008), Ecopath modeling (Arancibia and Neira 2008), and incidental sampling from hake
research trawl bycatch.

Peru
IMARPE conducts regular hydroacoustic stock assessments in addition to delivering monthly reports on
the state of the fishery. These are based on CPUE and size-age structure of landings (IMARPE 2013b),
although the accuracy of these methods in the case of D. gigas is unclear (Morales-Bojórquez, et al.
2001). Environmental data (such as surface temperature) are also monitored (Argüelles 2012).

Subfactor 3.1.4 – Management Record of Following Scientific Advice

Considerations: How often (always, sometimes, rarely) do managers of the fishery follow
scientific recommendations/advice (e.g. do they set catch limits at recommended levels)? A
Highly Effective rating is given if managers nearly always follow scientific advice.
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Chile Southeast Pacific, Jig

Moderately Effective

Chile has a robust fisheries science institution in IFOP and in the Subpesca regional scientific
committees, most relevantly the Comité Científico de Recursos Demersales Zona Centro-Sur (CCT-
RDZCS) and Zona Sur Austral (CCT-RDZSA). Recent quotas are within the bounds of scientific advice, but
these bounds are not fully rooted in quantitative stock assessments.

Peru Southeast Pacific, Jig

Highly Effective

IMARPE is a robust fisheries science institution, and there is no evidence that management does not
heed its advice in relation to the D. gigas fishery.

Subfactor 3.1.5 – Enforcement of Management Regulations

Considerations: Do fishermen comply with regulations, and how is this monitored? To achieve a
Highly Effective rating, there must be regular enforcement of regulations and verification of
compliance.

Chile Southeast Pacific, Jig

Moderately Effective

Weak enforcement of laws pertaining to bycatch, discards, and unreported fishing (Perez 2005) (OECD
2009) (Pramod, et al. 2014) is beginning to be addressed by stricter scientific monitoring, as required by
Ley 20.625 ((Subpesca 2012d), explained here: (Cocas 2014)). Fishing licenses are required and assigned
by fishery and area, and vessel monitoring systems (VMS) are currently mandatory on all large-scale
fishing vessels (FAO 2010b), with enforcement of registration effected by the Chilean Navy. This
designation includes artisanal vessels in the 12–18 m size range. Reporting of production statistics is
mandatory and enforced in both industrial and artisanal sectors (NFS 2004). But in-person port
monitoring of the artisanal sector is limited, with only 7% of artisanal landings inspected in 2012
(Sernapesca 2013b). Reported catch has remained below the TAC for both 2012 and 2013 (Sernapesca
2014).

Peru Southeast Pacific, Jig

Highly Effective
26

Licensing, onboard observers and vessel monitoring systems (the satellite surveillance system SISESTAT)
are required in the industrial fisheries. Catch in the artisanal fisheries is monitored by IMARPE onshore
(e.g., see (IMARPE 2013a)). Reporting of production statistics is mandatory and enforced in both
industrial and artisanal sectors. Captures have largely stayed below or at the recommended catch in
recent years.

Rationale:
Specific information on the vessel monitoring system is available from (FAO 2010c). Resolución
Ministerial No 415-2001-PE establishes the system of data collection for artisanal fisheries (PRODUCE
2001). See Fishing Mortality for details on adherence to recommended catch limits.The industrial fishery
is restricted to dedicated jigging vessels that operate within 30–200 miles of the Peruvian coast.
Specimens must have a minimum mantle length of 320 mm, and small squid must not make up more
than 20% of total catch (Arkhipkin, et al. 2015).

Subfactor 3.1.6 – Management Track Record

Considerations: Does management have a history of successfully maintaining populations at
sustainable levels or a history of failing to maintain populations at sustainable levels? A Highly
Effective rating is given if measures enacted by management have been shown to result in the
long-term maintenance of species overtime.

Chile Southeast Pacific, Jig

Moderately Effective

Though the D. gigas fishery itself is too young to have a clear track record, Chilean fisheries in general
have a mixed history. In recent decades, overfishing has led to several major stock collapses. But the
country is a member of the South Pacific Regional Fisheries Management Organisation (SPRFMO). The
SPFRMO includes a jumbo squid working group, although it does not appear to be regularly active. Chile
has also demonstrated a commitment to innovative near-shore management with the establishment of
territorial use rights in fisheries (TURFs) in the loco fishery (San Martín, Parma and Orensanz 2010). The
use of global quotas (as currently seen in the jumbo squid fishery) in lieu of catch shares has been
associated with increased competition and consequent overfishing (Costello, Gaines and Lynham 2008),
but there is no evidence that this is currently occurring in the Chilean D. gigas stock.

Rationale:
A 2006 evaluation of Chilean fisheries’ compliance with the UN Code of Conduct for Responsible Fishing
gave Chile generally passing grades, except in the category of “stocks, fleets and gear,” which includes
the management of fleet capacity; gear usage; discards, bycatch, and juveniles; and stock rebuilding.
Notably, the authors mentioned weaknesses in ecosystem-based management and contingency plans in
the event of environmental change (Kalikoski, et al. 2006b) (Kalikoski, et al. base their evaluation
27

primarily on (Zuleta 2004)).

Peru Southeast Pacific, Jig

Moderately Effective

The Peruvian D. gigas fishery is too recently established to have a clear history. Of concern is the fact
that one stock—the Peruvian anchoveta—has undergone collapse or near-collapse twice, in 1970 and in
1998. In a well-regarded decision, Peru responded to the stock’s continued instability in 2008 by
establishing maximum catch levels per vessel in place of a global quota (Aranda 2009). The use of global
quotas (as currently seen in the jumbo squid fishery) in lieu of catch shares has been associated with
increased competition and consequent overfishing (Costello, Gaines and Lynham 2008), but there is no
evidence that this is currently occurring in the Peruvian D. gigas stock.

Rationale:
A 2006 evaluation of Peruvian fisheries’ compliance with the UN Code of Conduct for Responsible
Fishing gave Peru generally passing grades, except in the category of application of the “precautionary
approach.” Notably, the authors mentioned weaknesses in the historical response to excess fishing,
although they praised the response to environmental change, such as that seen in unusual El Niño
Southern Oscillation (ENSO) regimes (Kalikoski, et al 2006a).

Subfactor 3.1.7 – Stakeholder Inclusion

Considerations: Are stakeholders involved/included in the decision-making process?
Stakeholders are individuals/groups/organizations that have an interest in the fishery or that
may be affected by the management of the fishery (e.g., fishermen, conservation groups, etc.).
A Highly Effective rating is given if the management process is transparent and includes
stakeholder input.

Chile Southeast Pacific, Jig

Moderately Effective

Artisanal fishers have formal recognition, are officially and non-transferably registered by Sernapesca,
and have protected quotas and a 5-mile exclusive fishing zone near shore. But artisanal and industrial
fisheries have clashed in recent years over alleged inequities in the allocation of quotas (Nelsen 2013).
Recent adoption of measures such as TURFs (Áreas de Manejo y Explotación de Recursos Bentónicos) in
some fisheries appears more stakeholder-inclusive (Gelcich, et al 2010). Catch statistics are published.
28

Peru Southeast Pacific, Jig

Moderately Effective

Artisanal fishers are officially recognized, and their development is provided for by fishery development
fund FONDEPES. The 5-mile zone near shore is reserved for artisanal fisheries using low-impact gear
types. A 2006 evaluation of Peru’s adherence to the UN Code of Conduct for Responsible Fisheries found
that individual fisheries allowed for stakeholder participation, but there was no specific requirement for
a stakeholder-inclusive decision-making process (Kalikoski 2006). Catch statistics are published.

Bycatch Strategy
Factor 3.2: Management of fishing impacts on bycatch species
Region / Method                    All Kept Critical    Strategy       Research Advice        Enforce
Chile Southeast Pacific            Yes        No        N/A            N/A      N/A           N/A
Jig
Peru Southeast Pacific             Yes        No        N/A            N/A        N/A         N/A
Jig

No bycatch species have been identified for the jumbo squid jig fisheries, so no assessment of bycatch
management is necessary.
29

Criterion 4: Impacts on the habitat and ecosystem
This Criterion assesses the impact of the fishery on seafloor habitats, and increases that base
score if there are measures in place to mitigate any impacts. The fishery’s overall impact on the
ecosystem and food web and the use of ecosystem-based fisheries management (EBFM)
principles is also evaluated. Ecosystem Based Fisheries Management aims to consider the
interconnections among species and all natural and human stressors on the environment.

The final score is the geometric mean of the impact of fishing gear on habitat score (plus the
mitigation of gear impacts score) and the Ecosystem Based Fishery Management score. The
Criterion 2 rating is determined as follows:

•   Score >3.2=Green or Low Concern
•   Score >2.2 and
30

•   1 (High)—Hydraulic clam dredge. Dredge or trawl gear fished on moderately sensitive
    habitats (e.g., cobble or boulder)
•   0 (Very High)—Dredge or trawl fished on biogenic habitat, (e.g., deep-sea corals, eelgrass
    and maerl)
    Note: When multiple habitat types are commonly encountered, and/or the habitat
    classification is uncertain, the score will be based on the most sensitive, plausible habitat
    type.

Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

None

Jigging is a low-impact gear type with no bottom contact (Arkhipkin, et al. 2015).

Factor 4.2 – Mitigation of Gear Impacts

Scoring Guidelines

•   +1 (Strong Mitigation)—Examples include large proportion of habitat protected from fishing
    (>50%) with gear, fishing intensity low/limited, gear specifically modified to reduce damage
    to seafloor and modifications shown to be effective at reducing damage, or an effective
    combination of ‘moderate’ mitigation measures.
•   +0.5 (Moderate Mitigation)—20% of habitat protected from fishing with gear or other
    measures in place to limit fishing effort, fishing intensity, and spatial footprint of damage
    caused from fishing.
•   +0.25 (Low Mitigation)—A few measures are in place (e.g., vulnerable habitats protected
    but other habitats not protected); there are some limits on fishing effort/intensity, but not
    actively being reduced.
•   0 (No Mitigation)—No effective measures are in place to limit gear impacts on habitats.
Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Not Applicable
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Factor 4.3 – Ecosystem-Based Fisheries Management

Scoring Guidelines

•   5 (Very Low Concern)—Substantial efforts have been made to protect species’ ecological
    roles and ensure fishing practices do not have negative ecological effects (e.g., large
    proportion of fishery area is protected with marine reserves, and abundance is maintained
    at sufficient levels to provide food to predators).
•   4 (Low Concern)—Studies are underway to assess the ecological role of species and
    measures are in place to protect the ecological role of any species that plays an
    exceptionally large role in the ecosystem. Measures are in place to minimize potentially
    negative ecological effect if hatchery supplementation or fish aggregating devices (FADs)
    are used.
•   3 (Moderate Concern)—Fishery does not catch species that play an exceptionally large role
    in the ecosystem, or if it does, studies are underway to determine how to protect the
    ecological role of these species, OR negative ecological effects from hatchery
    supplementation or FADs are possible and management is not place to mitigate these
    impacts.
•   2 (High Concern)—Fishery catches species that play an exceptionally large role in the
    ecosystem and no efforts are being made to incorporate their ecological role into
    management.
•   1 (Very High Concern)—Use of hatchery supplementation or fish aggregating devices (FADs)
    in the fishery is having serious negative ecological or genetic consequences, OR fishery has
    resulted in trophic cascades or other detrimental impacts to the food web.
Chile Southeast Pacific, Jig

Peru Southeast Pacific, Jig

Moderate Concern

Since 2002, Chile and Peru have been collaborating on the Global Environment Facility-funded joint
management of the Humboldt Current Large Marine Ecosystem (HCLME) (UNDP 2015), which includes
establishment of international Marine Protected Areas (Kalikoski 2006). A 2009 evaluation of fisheries in
the context of ecosystem-based management gave Peru just above a passing grade, and Chile a failing
grade (Pitcher, et al 2009), but D. gigas is an active area of research in both countries (Alegre et al.
2014) (and see detailed rationale) and is therefore deemed of “moderate” concern.

Rationale:
D. gigas acts as both a major predator of a variety of small mesopelagic organisms (Alarcón-Muñoz, et
al. 2008) (Field, et al. 2007) (Markaida and Sosa-Nishizaki 2003), and a major forage species for top
vertebrate predators (Nigmatullin, et al. 2001) (Field, et al. 2007), placing it in a bridging mesopredator
32

position and granting it exceptional importance. Though much of the ecology of D. gigas is unknown, its
sheer biomass also grants it a significant, if annually variable, trophic role. The species’ recent
population growth and range expansion, along with that of other cephalopods, has been attributed to
reduced competition as a result of overexploitation of groundfish stocks (Caddy and Rodhouse 1998),
top-down forcing as a result of tuna and billfish population declines (Zeidberg and Robison 2007), and to
climate change (potentially as a result of an expanding oxygen minimum layer or unusual El Niño
Southern Oscillation (ENSO) regime) (Field, et al. 2007) (Gilly, et al. 2013) (Keyl, et al. 2008). The
apparent coincidence of D. gigas’ expansion and the decline of the Chilean hake fishery has also led to a
widespread belief among fishers that squid predation has caused a decline in hake populations (pers.
comm., Patricio Galvez, IFOP 2015), but this is not generally supported by models (Arancibia and Neira
2008) (Ibáñez 2013). Political pressure stemming from this viewpoint may lead to insufficiently cautious
management approaches. Fisheries are urged to avoid this temptation: estimates suggest that global
predation on squid exceeds current fishing mortality (FAO 2005), which means that overfishing could
trigger significant cascading effects.

In its evaluation of ecosystem-based fisheries management in Chilean fisheries, Kalikoski et al.
specifically noted a lack of recognition of human impacts on fishery habitat and fisheries’ effects on
“species linked through the ecosystem to the target [species]” (Kalikoski, et al. 2006b).
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