Hakes: Biology and Exploitation

434 Pages·2015·12.569 MB·English

by  Hugo Arancibia

Table of Contents
Cover
Series Page
Title Page
Copyright
Dedication
List of contributors
Series Foreword
References
Preface
References
Acknowledgement
Chapter 1: European hake (Merluccius merluccius) in the Northeast Atlantic Ocean
1.1 Distribution
1.2 Physical environment and hydrography
1.3 Life history
1.4 Population dynamics
1.5 Ecosystem considerations
1.6 Fishery
1.7 Assessment
1.8 Management
1.9 Markets
1.10 Discussion
References
Chapter 2: Fisheries, ecology and markets of South African hake
2.1 Hydrography and physical environment
2.2 Species, distribution and stock structure
2.3 Biology and life history
2.4 The fishery
2.5 Markets and economics
2.6 Developments in assessment and management
2.7 Acknowledgements
References
Chapter 3: Biology and fisheries of the shallow-water hake (Merluccius capensis) and the
deep-water hake (Merluccius paradoxus) in Namibia
3.1 Introduction
3.2 Biology and life history
3.3 Fisheries
3.4 Advances in ecosystem based-approach to fisheries management (EAF)
3.5 Discussion
3.6 Acknowledgements
References
Chapter 4: Southern hake (Merluccius australis) in New Zealand: biology, fisheries and
stock assessment
4.1 Introduction
4.2 Biology
4.3 Fisheries
4.4 Discussion
4.5 Acknowledgements
References
Chapter 5: The biology, fishery and market of Chilean hake (Merluccius gayi gayi) in the
Southeastern Pacific Ocean
5.1 Introduction
5.2 The fishery
5.3 Ecological interactions
5.4 Habitat conditions
5.5 Products and markets
5.6 Discussion
References
Chapter 6: Biology and fishery of common hake (Merluccius hubbsi) and southern hake
(Merluccius australis) around the Falkland/Malvinas Islands on the Patagonian Shelf of the
Southwest Atlantic Ocean
6.1 Introduction
6.2 Species taxonomy and stock distribution
6.3 Biology and life history
6.4 Fisheries
6.5 Products and markets
6.6 Acknowledgements
References
Chapter 7: The biology and fishery of hake (Merluccius hubbsi) in the Argentinean–
Uruguayan Common Fishing Zone of the Southwest Atlantic Ocean
7.1 Background
7.2 Life history and ecological role
7.3 Distribution, population structure and migration patterns
7.4 Stock assessment and management
References
Chapter 8: Biology and fisheries of hake (Merluccius hubbsi) in Brazilian waters,
Southwest Atlantic Ocean
8.1 Introduction
8.2 Biology and life history
8.3 Brief description of the fishery and indicators
8.4 Assessment and management
8.5 Products and markets
8.6 Acknowledgements
References
Chapter 9: Biology, fisheries, assessment and management of Pacific hake (Merluccius
productus)
9.1 Introduction
9.2 Stocks
9.3 Biology, life history and ecology
9.4 Fisheries
9.5 Monitoring
9.6 Assessment and management strategy evaluation
9.7 Products and markets
Acknowledgements
References
Chapter 10: Biology and fisheries of New Zealand hoki (Macruronus novaezelandiae)
10.1 Introduction
10.2 The commercial hoki fishery in New Zealand
10.3 Fishery indicators
10.4 Stock assessment and management
10.5 Ecological sustainability and fishery interactions with the environment
10.6 Discussion
Acknowledgements
References
Chapter 11: Biology, fishery and products of Chilean hoki (Macruronus novaezelandiae
magellanicus)
11.1 Life history, taxonomy and distribution
11.2 Fishery
11.3 Stock assessment and management of hoki
11.4 Products and exports
11.5 Discussion
References
Chapter 12: An overview of hake and hoki fisheries: analysis of biological, fishery and
economic indicators
12.1 Introduction
12.2 Biological indicators
12.3 Fishery indicators
12.4 Economic indicators
12.5 Discussion
References
Index
End User License Agreement
List of Illustrations
Chapter 1: European hake (Merluccius merluccius) in the Northeast Atlantic Ocean
Figure 1.1 Preferential distribution of M. merluccius individuals of age 0, 4 and 5
years for the period 1987–2004 (adapted from Woillez et al., 2007).
Figure 1.2 Spatial distribution of individuals of age 0 years in M. merluccius in the
two main nursery areas (Bay of Biscay and Celtic Sea) from 1997 to 2007 (ICES,
2008).
Figure 1.3 Spatial distribution of individuals of age 0 years in M. merluccius in the
two main nursery areas (Bay of Biscay and Celtic Sea) from 2007 to 2012 (ICES,
2013).
Figure 1.4 Main physical features in the Celtic Sea and the Bay of Biscay (after Mason
et al., 2006).
Figure 1.5 Monthly spawning fraction and relative batch fecundity (adapted from
Murua et al., 2006). *: where estimates of either batch fecundity or spawning fraction
were missing, the values were taken from the previous month (July and October,
respectively).
Figure 1.6 Larvae otolith of age 27 days showing daily and sub-daily rings (after
CRAMER, 2012).
Figure 1.7 Northern and Southern hake stock landings by gear in 2010.
Figure 1.8 Time series of four abundance indices used to calibrate the assessment
model of northern stock of European hake. The acronyms correspond to French surveys
in the Bay of Biscay (FR-RESSGACQ) and in the Bay of Biscay and Celtic Sea (FR-
EVHOE); Spanish survey in the Porcupine Bank (SP-PORC) and the Irish Groundfish
Survey (IR-IGFS).
Figure 1.9 Time series of total landings (top panel, left), recruitment (top panel, right),
fishing mortality (lower panel, left) and spawning stock biomass of M. merluccius
(lower panel, right) in the northern hake stock since 1978–2012. With the exception of
landings, other indicators are output in the assessment model.
Figure 1.10 Time series of total landings (top panel, left), recruitment (top panel, right),
fishing mortality (lower panel, left) and spawning stock biomass of M. merluccius
(lower panel, right) in the southern hake stock since 1981–2012. With the exception of
landings, other indicators are output in the assessment model.
Chapter 2: Fisheries, ecology and markets of South African hake
Figure 2.1 The distribution and abundance of M. capensis and M. paradoxus in South
African waters. Contour plots of the densities (tonnes per nautical mile2) of the two
species are derived (interpolated using kriging) from pooled data collected during
summer (west coast) and autumn (south coast) surveys conducted over the period
2009–2011. The data from each survey were normalised to the mean of all surveys to
account for interannual differences in overall biomass. The 100-, 200- and 500-m
isobaths are also shown.
Figure 2.2 Growth of M. capensis and M. paradoxus. The curves are von Bertalanffy
growth models fitted to gender-disaggregated size-at-age data derived from otolith
samples collected during swept-area surveys conducted around the South African coast
between 1983 and 2008. Key: M. capensis males (solid line) and females (dots); M.
paradoxus males (broken line) and females (broken bold line).
Figure 2.3 Diets of M. capensis and M. paradoxus, estimated from the stomach
contents of demersal survey samples, 2010–2012. The proportions of each prey item in
the total stomach mass of hake of various size groups are illustrated in the left panel
and the composition of the hake component of the diet in the right panel. (a) M.
capensis, west coast; (b) M. paradoxus, west coast; (c) M. capensis, south coast; (d)
M. paradoxus, south coast.
Figure 2.4 Time-series of catches of hake in South African waters. (a) Total catches by
species over the period 1917–2012 (histograms), with the TACs imposed subsequent to
the declaration of South Africa's EFZ in 1977 (line). (b) Catches by sector over the
period 1978–2012 (to improve clarity, the vertical axis starts at 80,000 t). Key panel
up: grey = Merluccius capensis; white = Merluccius paradoxus; solid line = TAC.
Key panel down: grey dark = handline; grey = longline; grey light = inshore trawl;
white = deep-sea trawl.
Figure 2.5 The distribution of recent (year 2012) fishing effort of the hake longline,
deepsea trawl and inshore trawl fishing sectors. In 2008, the hake trawl sectors
voluntarily froze their ‘footprints’, and little if any fishing now takes place outside the
areas demarcated. The longline fishing areas in the chart, however, illustrate the areas
of greatest fishing effort; there is some longline fishing outside these areas, but most of
the sets are within the demarcated areas. The 100-, 200-, 500-, 1000- and 2000-m
isobaths are also shown. Note here that at a smaller scale than can be shown on this
map, there are areas of rocky ground within the trawl areas where trawling is
impossible but longlining is feasible.
Figure 2.6 Time-series of standardised stock–recruitment residuals for the baseline
assessment.
Figure 2.7 Trajectories of female spawning biomass for the most recent assessments
(RS1-2011 and RS1-2012), and the assessment conducted before the development of
the most recent OMP (RS1-2009). The horizontal lines in plots (a) represent the
spawning biomass that produces MSY, that is, B . The time series are shown in both
MSY
(a) absolute terms and (b) relative to estimates of pre-exploitation spawning biomass
Ksp. Panel (c) focuses on the post-2000 period to clarify recent trends and current
status.
Chapter 3: Biology and fisheries of the shallow-water hake (Merluccius capensis) and the
deep-water hake (Merluccius paradoxus) in Namibia
Figure 3.1 Images of (a) Merluccius capensis and (b) M. paradoxus (Photographs by
Rob Leslie).
Figure 3.2 Map outlining the Namibian coastline with depth contours. Circles indicate
the spawning centres of M. capensis – derived from (i) high densities of females with
high GSI (from Kainge et al., 2007) and (ii) aggregations of spawning adults and
juveniles (Wilhelm et al., 2015).
Figure 3.3 Weight–length relationships (a) and maturity-length ogives (b) of Namibian
M. paradoxus (dashed line) and M. capensis (solid line).
Figure 3.4 Namibian M. capensis proposed spawning centres and migration patterns
from nursery (0 years old and 3 cm TL) to 4+ years old spawning fish (>50 cm TL).
Ellipses indicate spawning and nursery areas. Arrows show inshore-offshore and
alongshore migration. Temperatures refer to the range of the means of the coldest and
warmest months at specific depths and areas (from Wilhelm et al., 2015).
Figure 3.5 Diet composition (proportion wet mass) of stomach contents of fish
collected during two surveys January/February 1999 of (a) M. capensis (n = 859) and
(b) M. paradoxus (n = 297) (J.-P. Roux, MFMR, unpublished data).
Figure 3.6 Number of commercial trawls conducted by grid cell 1998 to 2007 (5 nmi ×
0.1° resolution) (from Johnsen and Kathena, 2012).
Figure 3.7 Annual total catch (×103 t) from 1999 to 2011 of (a) Namibian hake caught
in the different fisheries (hake trawl and longline fisheries are hake-directed, mid-
water trawl fishery targets horse mackerel) and (b) the main by-catch of the hake-
directed trawl fishery.
Figure 3.8 Annual total catch of the Namibian hake fishery (×103 t) from 1964 to 2011
(white bars), and total allowable catch (TAC) limits set in Namibia from 1976 to 2012
(black dashes).
Figure 3.9 Swept-area biomass survey abundance indices (biomass in 103 t) and
associated standard deviations for M. capensis (solid diamonds) and M. paradoxus
(open squares) since the start of the Namibian Ministry of Fisheries and Marine
Resources (MFMR) surveys in 1990. ‘W’ indicates that that particular survey is used
in the ‘winter survey’ time series within the stock assessment model, while ‘N’
indicates it is not used. All other surveys are used in the ‘summer survey’ time series.
The combined biomass estimate for both species is currently used in the assessment.
Figure 3.10 GLM standardised (solid line) and unstandardised (dashed line) catch per
unit effort (CPUE) series for the Namibian hake fleet (both M. capensis and M.
paradoxus combined) from 1992 to 2011. Annual total catch in (103 tonnes, 1990 to
2011) is super-imposed as black squares.
Chapter 4: Southern hake (Merluccius australis) in New Zealand: biology, fisheries and
stock assessment
Figure 4.1 The location of 7464 bottom trawl research stations (crosses) that have
caught southern hake (as at April 2012) around New Zealand. Approximate isobaths at
200 m (dashed line) and 1000 m (dotted line) are also shown.
Figure 4.2 Map of the New Zealand EEZ, showing the four southern hake Quota
Management Areas (Fishstocks HAK 1, HAK 4, HAK 7 and HAK 10), the approximate
areas of the three hypothesised biological stocks (west coast South Island, light blue;
Chatham Rise, mauve; Sub-Antarctic, pink), the main hake spawning grounds (*) and
locations mentioned in the text. Isobaths at 500 m (green line) and 1000 m (blue line)
are also shown.
Figure 4.3 Estimated Bayesian posterior distributions of year-class strengths, from
stock assessment models of the three southern hake biological stocks. The dashed
horizontal line indicates the average year-class strength, that is, the long-term median
year class strength as indicated from assessment modelling of each stock, standardised
to equal 1. Individual distributions estimated for each year are the marginal posteriors,
with horizontal lines indicating the median.
Figure 4.4 Maturity ogives fitted as logistic curves to raw proportion mature at age
data (circles) for the three southern hake biological stocks.
Figure 4.5 Estimated instantaneous natural mortality (M) ogives (solid lines, with 95%
credible intervals shown as dashed lines) for the Sub-Antarctic and WCSI biological
stocks. The horizontal dotted lines show the constant value of M (0.19) used in other
assessment models when M is not estimated.
Figure 4.6 Biomass estimates of southern hake from bottom trawl swept area surveys
by R.V. Tangaroa on the Chatham Rise in January, and the Sub-Antarctic in November–
December and April–May, with approximate 95% confidence intervals.
Figure 4.7 Estimated catch-at-age distributions (sexes combined) for southern hake
caught in trawl fisheries during the 2008–2009 fishing year in the three biological stock
areas, and during research trawl surveys of the Sub-Antarctic (December 2008) and
Chatham Rise (January 2009). The last bar in each distribution represents a ‘plus
group’ – ages 21 and older for the Sub-Antarctic stock, and ages 19 and over for the
Chatham Rise and WCSI stocks.
Figure 4.8 Standardised CPUE (catch per unit of effort) series estimated for trawl
fisheries, and used in stock assessment modelling, for each of the three southern hake
biological stocks. Key: solid line = Sub-Antarctic; broken line = Chatham Rise; dots =
WCSI.
Figure 4.9 Estimated median trajectories (solid lines, with 95% credible intervals
shown as dashed lines) for absolute spawning biomass (t) and relative biomass (as a
percentage of unfished spawning biomass, B ) from the base case stock assessment
0
models for the Sub-Antarctic, Chatham Rise, and west coast South Island southern hake
biological stocks. Horizontal dotted lines at 40% B in the right hand panels show the
0
minimum management target level.
Chapter 5: The biology, fishery and market of Chilean hake (Merluccius gayi gayi) in the
Southeastern Pacific Ocean
Figure 5.1 Distribution of the stock of M. gayi gayi and fishery distribution off central
Chile.
Figure 5.2 Landings of M. gayi gayi (Total, Industrial and Artisanal) and total
allowable catch.
Figure 5.3 Catch per unit effort (kg/trip) in the artisanal long-line fleet targeting M.
gayi gayi (after Subpesca, 2012).
Figure 5.4 Mean length (cm) of M. gayi gayi landed by year in the artisanal fleet
according to fishing gear (after Subpesca, 2012).
Figure 5.5 Percentage of juvenile of M. gayi gayi by year in the artisanal landings
according to fishing gear (after Subpesca, 2012).
Figure 5.6 Catch per unit effort rate (t/hour) in the industrial fleet by year (after
Subpesca, 2012).
Figure 5.7 Percentage of juvenile of M. gayi gayi in landings of the industrial fleet by
year (after Subpesca, 2012).
Figure 5.8 Mean of total length of M. gayi gayi in the industrial trawl fishery by year
(after Subpesca, 2012).
Figure 5.9 Catch-at-age composition of M. gayi gayi from 1968 to 2011 (after
Arancibia, 2010).
Figure 5.10 Stock indicators for M. gayi gayi: (a) total biomass, (b) adult biomass, (c)
spawning biomass and (d) recruitment. In recruitment plot, solid line is average
recruitment. Model 1 ( ) = model without D. gigas mortality; Model 2 ( ) =
model with D. gigas mortality. Population indicators for Chilean hake (a) total
biomass, (b) adult biomass, (c) spawning biomass, and (d) recruitment. In recruitment
plot, solid line is average recruitment. Model 1 ( ) = Model without jumbo squid
mortality; Model 2 ( ) = Model with jumbo squid mortality.
Figure 5.11 Fishing mortality (F) and jumbo squid (D. gigas) predation mortality (J)
for M. gayi gayi. Model 1 = model without D. gigas mortality; Model 2 = model with
D. gigas mortality.
Figure 5.12 Mortality coefficients in Chilean hake estimated using the Ecopath with
Ecosim model (see Neira and Arancibia, 2004).
Figure 5.13 Time series of vertical distribution of M. gayi gayi schools during the main
spawning period (August).
Figure 5.14 Spatial and temporal distribution of temperature (a), salinity (b) and
oxygen (c) in south central zone.
Figure 5.15 Number of plants (top panel) and production of manufacture products
(lower panel) derived from Chilean hake 2007–2011 (after Subpesca, 2012).
Figure 5.16 Exports of Chilean hake according to production line in year 2011,
considering price (top panel) and volume (low panel). Primary y-axis: frozen and
others; secondary y-axis: fresh frozen (after Subpesca, 2012).
Figure 5.17 Main markets for M. gayi gayi in year 2011 in terms of exports (in tonnes;
after Subpesca, 2012).
Figure 5.18 Number of jobs in the industrial (plant and fleet) and artisanal sectors in
the fishery of M. gayi gayi by year from 2007 to 2011 (after Subpesca, 2012).
Chapter 6: Biology and fishery of common hake (Merluccius hubbsi) and southern hake
(Merluccius australis) around the Falkland/Malvinas Islands on the Patagonian Shelf of the