Download Weakfish – Full Species Report

WEAKFISH
Cynoscion regalis
Sometimes known as Sea Trout, Grey Trout, Bastard Trout
SUMMARY
Weakfish are a species of fast growing fish found from Massachusetts to Florida, although they
are most commonly found between New York and North Carolina. They are highly dependent on
estuaries for food, shelter and spawning. Weakfish populations are depleted throughout their
range and it is thought that increased predation and other natural factors, and not fishing
pressure, are the main reasons for their low numbers. The Atlantic States Marine Fisheries
Commission manages Weakfish and individual states implement management measures.
Historically, the majority of Weakfish landings came from commercial fisheries in North
Carolina, Virginia, and New Jersey. Recently, recreational harvest from Mid-Atlantic States has
equaled or exceeded commercial harvest. Most Weakfish are caught commercially in gillnets,
which have a low to medium impact on the seafloor depending on where in the water column
they are placed, and moderate levels of bycatch. Barton Seaver says, “This bass-like fish has a
firm flake but a soft and luxurious texture. Very sweet and delicate in flavor, best cooked well
done. Try broiling, grilling, or sautéing.”
Criterion
Points
Final Score
Life History
2.75
2.40 - 4.00
Abundance
0.00
1.60 - 2.39
Habitat Quality and Fishing Gear Impacts
2.00
0.00 - 1.59
Management
2.00
Bycatch
2.25
Final Score
1.80
Color
Color
LIFE HISTORY
Core Points (only one selection allowed)
If a value for intrinsic rate of increase („r‟) is known, assign the score below based on this value.
If no r-value is available, assign the score below for the correct age at 50% maturity for females
if specified, or for the correct value of growth rate ('k'). If no estimates of r, age at 50% maturity,
or k are available, assign the score below based on maximum age.
1.00
Intrinsic rate of increase <0.05; OR age at 50% maturity >10 years; OR growth rate
<0.15; OR maximum age >30 years.
2.00
Intrinsic rate of increase = 0.05-0.15; OR age at 50% maturity = 5-10 years; OR a growth
rate = 0.16–0.30; OR maximum age = 11-30 years.
3.00
Intrinsic rate of increase >0.16; OR age at 50% maturity = 1-5 years; OR growth
rate >0.30; OR maximum age <11 years.
Weakfish reach sexual maturity by 1 year of age, and can live for 17 years (LowerreBarbieri et al. 1996; NEFSC 2009B) reaching a weight of 9 kg or 20 lbs (NEFSC 2009B).
In the Chesapeake Bay and Middle Atlantic Bight, sexual maturity is reached at 164 mm
and 170 mm total length (TL) for males and females respectively (Lowerre-Barbieri et al.
1996). Size at sexual maturity in North Carolina waters ranges from 130-230 mm TL for
males and 150-256 mm TL for females (Merriner 1976; Shepherd and Grimes 1984).
Weakfish grow very quickly during their first year and females attain slightly larger sizes
(length) than males (Lowerre-Barbierri et al. 1995), although growth varies depending on
the location, habitat and year (Shepherd and Grimes 1983; Shepherd 1988; Szedlmayer et
al. 1990). For example, Weakfish grow slower in the northern end of their range
(Shepherd 1988). Growth rates are high with k = 0.98 (Lowerre-Barbierri et al. 1995) but
may have slowed in recent years (Kahn 2002). Juvenile growth rates in Delaware Bay
range from 0.69 mm to 0.97 mm per day (Paperno et al. 2000). There were differences in
growth rates within Delaware Bay, with faster growth occurring in the middle bay,
medium in the lower bay and slowest in the upper bay (Paperno et al. 2000). Low food
levels during 1990 in Delaware Bay have been implicated in slower growth rates of
Weakfish larvae (Duffy et al. 1996). In the Hudson River, juvenile growth has been
estimated to range from 0.91 to 1.02 mm per day (Shrump and Chambers 2003).
Points of Adjustment (multiple selections allowed)
-0.25 Species has special behaviors that make it especially vulnerable to fishing pressure
(e.g., spawning aggregations; site fidelity; segregation by sex; migratory bottlenecks;
unusual attraction to gear; etc.).
Weakfish form large aggregations as they move south and offshore (Mercer 1985), and
are targeted by fisheries as they migrate (Brust et al. 2009). For example, overwintering
Weakfish are targeted during the winter in North Carolina (Brust et al. 2009). Site fidelity
has been observed in the Mullica River-Great Bay estuary, NJ (Turnure 2010) and it has
been estimated that up to 80% of Weakfish return to their original estuaries to spawn
(Thorrold et al. 2001), which could make them more susceptible to depletion.
-0.25 Species has a strategy for sexual development that makes it especially vulnerable to
fishing pressure (e.g., age at 50% maturity >20 years; sequential hermaphrodites;
extremely low fecundity).
-0.25 Species has a small or restricted range (e.g., endemism; numerous evolutionarily
significant units; restricted to one coastline; e.g., American lobster; striped bass;
endemic reef fishes).
Weakfish are found along the Atlantic coast from Massachusetts to Florida, but
sometimes are found as far north as Nova Scotia, Canada (Wilk 1979; NEFSC 2009B).
They are most commonly found between New York and North Carolina (Wilk 1979) and
there appear to be multiple populations with different life history patterns (NEFSC
2009B), although genetic studies do not support this theory (Crowford et al. 1989; Graves
et al. 1993; Cordes and Graves 2003). Weakfish are managed as a single population
(NEFSC 2009B). Weakfish migrate into estuaries, bays and reserves during the spring for
spawning and migrate offshore or towards the southern region of their range to
overwinter in the fall (Bigelow and Schroeder 1953; Wilk 1979). More adults spend
summers in ocean habitats in the northern range and larger Weakfish move inshore first
(ASMFC 2010). Areas of the continental shelf from the Chesapeake Bay to Cape
Lookout, North Carolina, serve as important overwintering areas (Mercer 1985).
-0.25 Species exhibits high natural population variability driven by broad-scale
environmental change (e.g. El Nino; decadal oscillations).
Weakfish abundance may be influenced by changes in temperature, although this has not
yet been proven (NEFSC 2009a). Preliminary evidence from the latest population
assessment looked at correlations between 65 to 70 year oscillations in sea surface
temperatures in the Atlantic Ocean and Weakfish abundance and found that Weakfish
landings were highest during the late 1970‟s and 80‟s when sea surface temperatures
were the lowest (Brust et al. 2009). However, we have not subtracted points since further
information is needed.
+0.25 Species does not have special behaviors that increase ease or population consequences of
capture OR has special behaviors that make it less vulnerable to fishing pressure (e.g.,
species is widely dispersed during spawning).
+0.25 Species has a strategy for sexual development that makes it especially resilient to
fishing pressure (e.g., age at 50% maturity <1 year; extremely high fecundity).
Weakfish have a long spawning season that begins in the spring and occurs in estuaries
and bays (Bigelow and Schroeder 1953; NEFSC 2009B). The main spawning areas are
located from North Carolina to Montauk New York, with some spawning also observed
in Georgia and South Carolina (Mercer 1985). Spawning occurs from March to
September, with peaks from April to June, in North Carolina (Merriner 1976). In the
Chesapeake Bay, spawning occurs from May to August (Lowerre-Barbieri et al. 1996)
and in the Delaware Bay to New York from May to mid-July (Shepherd and Grimes
1984). For example, in the Hudson River, spawning begins in April and peaks in late
June (Shrump and Chambers 2003). Differences in spawning activity occur between
years and locations (Lowerre-Barbieri et al. 1996). Weakfish can produce between
75,000 to 518,000 eggs at a time, with the number of eggs increasing as female size
increases (Lowerre-Barbieri et al. 1996).
+0.25 Species is distributed over a very wide range (e.g., throughout an entire hemisphere or
ocean basin; e.g., swordfish; tuna; Patagonian toothfish).
+0.25 Species does not exhibit high natural population variability driven by broad-scale
environmental change (e.g., El Nino; decadal oscillations).
2.75 Points for Life History
ABUNDANCE
Core Points (only one selection allowed)
Compared to natural or un-fished level, the species population is:
1.00
Low: Abundance or biomass is <75% of BMSY or similar proxy (e.g., spawning
potential ratio).
Weakfish are considered to be in a “depleted state”, based on the most recent population
assessment conducted in 2008 (NEFSC 2009B). Fishing mortality has remained
relatively stable at moderate levels over the last decade, but it is not possible to determine
whether overfishing is occurring without a suitable fishing mortality reference point.
However, the stock has had negative productivity in recent years due to exceedingly high
rates of natural mortality (NEFSC 2009b). The spawning stock biomass (SSB) in 2007
was below the biomass threshold level and fishing mortality has been higher than target
levels in almost every year since 1981 (NEFSC 2009B). During the last assessment, one
model estimated the spawning stock biomass (SSB) to be around 5% of the maximum
spawning potential; however, these reference points were not considered suitable for
management purposes (NEFSC 2009B). It appears that natural mortality and not fishing
mortality is the main cause of this species decline, therefore even a complete closure of
the fishery would do little to improve the status of Weakfish (Kahn et al. 2006; NEFSC
2009a).
2.00
Medium: Abundance or biomass is 75-125% of BMSY or similar proxy; OR population
is approaching or recovering from an overfished condition; OR adequate information on
abundance or biomass is not available.
3.00
High: Abundance or biomass is >125% of BMSY or similar proxy.
Points of Adjustment (multiple selections allowed)
-0.25 The population is declining over a generational time scale (as indicated by biomass
estimates or standardized CPUE).
Age-1 Weakfish abundances from one model (index-based) used in the latest population
assessment varied considerably from 1981 to 2008 (NEFSC 2009a). For example,
abundance was high from 1981 to 1988 but then decreased substantially from 1989 to
1993 (NEFSC 2009a). A rise in abundance occurred again from 1994 to 1996, followed
by a steady decline through 2008, which had the lowest estimate in the time series
(NEFSC 2009a). However, abundances of age-1 Weakfish from a second model (surplus
production) stayed high from 1982 to 1986 and from 1993 to 1994, but fell after 1995
and has remained low, especially since 2001 (NEFSC 2009a).
Abundances based on commercial fisheries data have shown a strong decline over time
(Brust et al. 2009). For example, in Virginia, catch per unit effort (CPUE) has fallen since
the late 1990‟s with strong declines occurring since 2002 (NEFSC 2009a). The Delaware
Bay gillnet fishery CPUE has declined steadily since 2000 and the Potomac River pound
net fishery CPUE has declined since 2002 (Brust et al. 2009).
-0.25 Age, size or sex distribution is skewed relative to the natural condition (e.g.,
truncated size/age structure or anomalous sex distribution).
There are several sources of information that indicate changes to the size/age structure of
Weakfish over time. Data from fishery independent trawl surveys, such as the one in
Delaware Bay, shows that age structure was truncated to primarily fish age 4 or younger
by the early 1990s. Implementation of management requirements resulted in an increase
in age structure during the mid 1990s, but abundance of these older fish has since
declined again. Similar trends have been observed in the age distribution of both
commercial and recreational harvest. In addition, size at age has also decreased in recent
years, with a nearly 50% decline in weight at age of 3-5 year old Weakfish caught in
commercial fisheries (NEFSC 2009a).
-0.25 Species is listed as "overfished" OR species is listed as "depleted", "endangered",
or "threatened" by recognized national or international bodies.
Weakfish are in a “depleted” state (NEFSC 2009B).
-0.25 Current levels of abundance are likely to jeopardize the availability of food for
other species or cause substantial change in the structure of the associated food web.
Analyses have preliminarily linked increases in Weakfish juvenile mortality since 1998
and the corresponding decline in Weakfish biomass to increases in species such as striped
bass and spiny dogfish and therefore increased predation mortality (NMFS 2008; NEFSC
2009a). Analyses also suggest that the increase in striped bass abundance has led to
increased competition and a subsequent reduction in prey (menhaden) availability for
Weakfish, which may have also played a role in the increased Weakfish mortality
(NEFSC 2009a).
Weakfish typically begin eating fish such as anchovies at a young age and are eating
primarily larger fish, such as menhaden and spot by age 2 (Hartman and Brandt 1995;
Latour et al. In review). The diet of juvenile Weakfish is mostly made up of shrimp in the
Delaware Bay and of anchovies and shrimp in the Chesapeake Bay (Grecay and Targett
1996; Latour et al. in review). Shrimp also make up a large portion of adult Weakfish‟s
diet in the Chesapeake Bay (Latour et al. In review). Adults typically tend to eat more
fish, which is typically made up of menhaden and other similar species (Merriner 1975;
Hartman and Brandt 1995). However, there appear to have been changes in their food
composition over time. For example, evidence from the Chesapeake Bay in the 1990‟s
showed that 80% of the diet of Weakfish (ages 0-2) was made up of menhaden, spot and
anchovies (Hartman and Brant 1995) but by 2002, 30% of the diet of age 0-5 Weakfish
was made up of invertebrates and only 40% consisted of fish (Hartman and Brandt 1995;
Latour et al. In review). Specifically, anchovy and menhaden have become less prevalent
in Weakfish diets since the 1990‟s and spot are rarely present in their diets anymore
(Hartman and Brandt 1995; Latour et al. In review). Weakfish older than age 2 are also
now substituting invertebrates and anchovy for menhaden (Hartman and Brandt 1995;
Latour et al. In review).
We have subtracted points because there is ample evidence of changes to the food web
structure due to low abundances of Weakfish.
+0.25 The population is increasing over a generational time scale (as indicated by biomass
estimates or standardized CPUE).
+0.25 Age, size or sex distribution is functionally normal.
+0.25 Species is close to virgin biomass.
+0.25 Current levels of abundance provide adequate food for other predators or are not known
to affect the structure of the associated food web.
0.00 Points for Abundance
HABITAT QUALITY AND FISHING GEAR IMPACTS
Core Points (only one selection allowed)
Select the option that most accurately describes the effect of the fishing method upon the habitat
that it affects
1.00
The fishing method causes great damage to physical and biogenic habitats (e.g., cyanide;
blasting; bottom trawling; dredging).
2.00
The fishing method does moderate damage to physical and biogenic habitats (e.g.,
bottom gillnets; traps and pots; bottom longlines).
Historically, the majority of commercial Weakfish landings (37%) have occurred during
the winter months in North Carolina (NEFSC 2009B). Fishing also occurs in the spring
and summer from Pamlico Sound, North Carolina through Peconic Bay on eastern Long
Island, New York (NEFSC 2009B). North Carolina, Virginia and New Jersey landings
have accounted for 70% of total landings since 1950 (NEFSC 2009B). Gillnets currently
make up around 45% of total landings, trawl gear makes up around 20% of these
landings, and pound nets and haul seines make up between 10-20% of landings (NEFSC
2009B). Gillnets can have a low to medium impact on bottom habitat, dependent on
where they are placed in the water column (Morgan and Chuenpagdee 2003). Midwater
trawls can have a very low impact on bottom habitat, while bottom trawls have a very
high impact on bottom habitat (Morgan and Chuenpagdee 2003). We have selected a
middle score to account for the variability in habitat damage by different gear types.
3.00
The fishing method does little damage to physical or biogenic habitats (e.g., hand
picking; hand raking; hook and line; pelagic long lines; mid-water trawl or gillnet; purse
seines).
Points of Adjustment (multiple selections allowed)
-0.25 Habitat for this species is so compromised from non-fishery impacts that the ability
of the habitat to support this species is substantially reduced (e.g., dams; pollution;
coastal development).
Weakfish are found in estuarine and shallow marine waters, with temperatures ranging
from 17 to 26.5° C (Merriner 1976). In the spring, Weakfish move north and inshore to
spawn and migrate offshore during the fall (Wilk 1976). In Mullica River-Great Bay
estuary, NJ, adult Weakfish were found in the bay, lower river and subtidal creeks during
and after spawning but did not commonly use inlets or upper river habitats during these
time periods (Turnure 2010). There is some indication of site fidelity for Weakfish in this
bay (seasonally and daily) (Turnure 2010). In the Delaware Bay, there appear to be shifts
in the location of prime nurseries areas within the estuaries over time (Tellechea et al.
2010).
The following have been identified as threats to Weakfish habitat: coastal development,
dredging, water quality degradation, conversion of coastal wetlands to agricultural areas,
alteration of freshwater flows and power plant cooling facilities (ASMFC 2010). The
Atlantic States Marine Fisheries Commission has recommended that restoration and
maintenance of important Weakfish habitat should be promoted, restrictions for projects
in spawning and overwintering areas should be well defined and projects that involve
water removal from nursery habitats should be thoroughly evaluated (ASMFC 2010).
We have not subtracted points because there is no evidence that these potential threats
have substantially reduced the ability of these habitats to support Weakfish.
-0.25 Critical habitat areas (e.g., spawning areas) for this species are not protected by
management using time/area closures, marine reserves, etc.
-0.25 No efforts are being made to minimize damage from existing gear types OR new or
modified gear is increasing habitat damage (e.g., fitting trawls with roller rigs or
rockhopping gear; more robust gear for deep-sea fisheries).
-0.25 If gear impacts are substantial, resilience of affected habitats is very slow (e.g., deep
water corals; rocky bottoms).
+0.25 Habitat for this species remains robust and viable and is capable of supporting this
species.
+0.25 Critical habitat areas (e.g., spawning areas) for this species are protected by management
using time/area closures, marine reserves, etc.
+0.25 Gear innovations are being implemented over a majority of the fishing area to minimize
damage from gear types OR no innovations necessary because gear effects are minimal.
+0.25 If gear impacts are substantial, resilience of affected habitats is fast (e.g., mud or sandy
bottoms) OR gear effects are minimal.
2.00 Points for Habitat Quality and Fishing Gear Impacts
MANAGEMENT
Core Points (only one selection allowed)
Select the option that most accurately describes the current management of the fisheries of this
species.
1.00
Regulations are ineffective (e.g., illegal fishing or overfishing is occurring) OR the
fishery is unregulated (i.e., no control rules are in effect).
2.00
Management measures are in place over a major portion over the species' range but
implementation has not met conservation goals OR management measures are in
place but have not been in place long enough to determine if they are likely to
achieve conservation and sustainability goals.
Weakfish are managed under the Atlantic States Marine Fisheries Commission (ASMFC)
Interstate Fishery Management Plan for Weakfish (NEFSC 2009B). This plan was first
implemented in 1985 and included only voluntary management measures, which were
instituted to varying degrees by individual states (Mercer 1985). In 1991, Amendment 1
was implemented, which established target fishing mortality rates (Seagraves 1991).
Amendment 2 was passed in 1995 and included minimum size limits, gear restrictions,
bycatch reductions, and reductions to fishing mortality (ASMFC 1994). Amendment 3
included season and area closures and stricter bycatch reduction measures (ASMFC
1996) and Amendment 4, established new target reference points (ASMFC 2002).
Specific state regulations include size limits, seasons and bag limits in Massachusetts and
Connecticut and size limits, seasons, bag limits, gear restrictions, and bycatch limits in
Rhode Island, New York, New Jersey, Maryland, and Virginia (ASMFC 2010b). Size
limits, seasons, bag limits, gear restrictions, bycatch limits and required use of bycatch
reduction devices in shrimp trawls are used in North Carolina and size limits, seasons,
bag limits and gear restrictions are used in Delaware (ASMFC 2010b). Size limits,
seasons, bag limits and bycatch limits are used in Puerto Rico and size limits, bag limits
and required use of bycatch reduction devices in shrimp trawls are used in South
Carolina, North Carolina, Georgia and Florida (ASMFC 2010b).
The ASMFC and the Inter-state Fisheries Management Policy Board are responsible for
oversight and management of management activities, the Weakfish Management Board is
responsible for carrying out activities under the amendments and oversees the activities
of the Plan Development (PDT), Technical Committee and Stock Assessment
Subcommittee (ASMFC 2002). The PDT and Weakfish Plan Review Team (PRT)
provide technical support to carry out and document decisions of the Management Board
(ASMFC 2002). The Technical Committee acts as a liaison between the federal and state
agencies and provides scientific and technical advice to the management board, PDT and
PRT (ASMFC 2002). Population assessments are conducted by the Weakfish Stock
Assessment Subcommittee and the Weakfish Advisory Panel provides advice to the
board on the management program (ASMFC 2002).
We have assigned a middle score, because despite having management measures in place,
Weakfish are still in a depleted state.
3.00
Substantial management measures are in place over a large portion of the species range
and have demonstrated success in achieving conservation and sustainability goals.
Points of Adjustment (multiple selections allowed)
-0.25 There is inadequate scientific monitoring of stock status, catch or fishing effort.
-0.25 Management does not explicitly address fishery effects on habitat, food webs, and
ecosystems.
Management does not explicitly address fishery effects on habitat, food webs and
ecosystems.
-0.25 This species is overfished and no recovery plan or an ineffective recovery plan is in
place.
-0.25 Management has failed to reduce excess capacity in this fishery or implements subsidies
that result in excess capacity in this fishery.
+0.25 There is adequate scientific monitoring, analysis and interpretation of stock status,
catch and fishing effort.
Several states require mandatory reporting of Weakfish landings but other states and the
National Marine Fisheries Service do not (NEFSC 2009B). Biological samples (length,
weight and ages) are taken from state-specific port sampling programs (NEFSC 2009B)
and Massachusetts, Rhode Island, Connecticut, New York, Delaware, Maryland,
Virginia, and North Carolina provide young-of-year estimates of abundance (Cimino
2010). Estimates of Weakfish age 0 to 5+ are also provided by NMFS, New Jersey,
Delaware, North Carolina, Georgia, SEAMAP and NEAMAP (Cimino 2010). Other age
specific estimates of abundance are provided by the Northeast Fisheries Science Center
trawl survey and the Southeast Area Monitoring and Assessment Program survey
(Cimino 2010).
The Weakfish Technical Committee has recommended that monitoring of Weakfish,
striped bass and spiny dogfish diets be initiated over a broad regional scale, catch and
effort data including size and age composition should be collected, population mortality
rates need to be determined, gear characteristics should be defined, length frequency
sampling should be increased, discard mortality rates should be estimated, and trawl
bycatch should be quantified (Brust et al. 2009).
+0.25 Management explicitly and effectively addresses fishery effects on habitat, food webs,
and ecosystems.
+0.25 This species is overfished and there is a recovery plan (including benchmarks,
timetables and methods to evaluate success) in place that is showing signs of success
OR recovery plan is not needed.
Weakfish are in a “depleted state” but Amendment 4 to their fishery management plan
has the goal to recover Weakfish to healthy levels through interstate management
(ASMFC 2002; Cimino 2010). These efforts include: defining target and threshold levels
for overfishing, restoring Weakfish age and size structure, returning Weakfish to their
original range, developing equitable and compatible interstate management measures,
identifying essential habitat and to establish procedures to determine individual states
compliance with management measures (ASMFC 2002). In addition, Addendum IV to
this Amendment was approved in 2009, and implemented in the middle of 2010, in
response to the results of the last population assessment (Cimino 2010). This
Addendum‟s goal is to create more appropriate biological reference points to reduce
fishing mortality (Cimino 2010). However, the success of these measures has not yet
been assessed so we have not added any points at this time.
+0.25 Management has taken action to control excess capacity or reduce subsidies that result in
excess capacity OR no measures are necessary because fishery is not overcapitalized.
2.00 Points for Management
BYCATCH
Core Points (only one selection allowed)
Select the option that most accurately describes the current level of bycatch and the
consequences that result from fishing this species. The term, "bycatch" used in this document
excludes incidental catch of a species for which an adequate management framework exists. The
terms, "endangered, threatened, or protected," used in this document refer to species status that is
determined by national legislation such as the U.S. Endangered Species Act, the U.S. Marine
Mammal Protection Act (or another nation's equivalent), the IUCN Red List, or a credible
scientific body such as the American Fisheries Society.
1.00
Bycatch in this fishery is high (>100% of targeted landings), OR regularly includes a
"threatened, endangered or protected species."
2.00
Bycatch in this fishery is moderate (10-99% of targeted landings) AND does not
regularly include "threatened, endangered or protected species" OR level of
bycatch is unknown.
Fisheries targeting Weakfish have been reported to interact with marine mammals,
primarily right whales, bottlenose dolphins and harbor porpoises, in several regions
(ASMFC 2002).
The Mid-Atlantic gillnet fishery is considered a Category I fishery (frequent incidental
mortality or serious injury of marine mammals) under the Marine Mammal Protection act
due to the incidental capture of the following species: bottlenose, common and whitesided dolphins, gray, harp and harbor seals, harbor, humpback and minke whales and
long and short-finned whales (FR 2010). Between 1996 and 2000, there were 12
interactions between gillnets and bottlenose dolphins observed in this fishery, which
calculates to around 233 total interactions for the fishery (all vessels, not just those with
fishery observers present) (Waring et al. 2002). A total of 114 harbor porpoises were
observed caught in the Mid-Atlantic coastal gillnet fishery between 1995 and 2000
(Waring et al. 2002).
The Northeast sink gillnet fishery is also considered a Category I fishery due to
interactions with bottlenose, common, Risso‟s and white sided dolphins, gray, harbor,
harp and hooded seals, harbor porpoises and fin, humpback, minke, and North Atlantic
whales (FR 2010). From 1990 to 2000, 452 harbor porpoise mortalities were observed in
this fishery, which calculates to between 270 to 2,900 animals a year for the entire fishery
(Waring et al. 2002).
The Chesapeake Bay inshore gillnet fishery is considered a Category II fishery
(occasional incidental mortality or serious injury of marine mammals), although no
interactions with marine mammals have occurred within the past five years and the North
Carolina inshore gillnet fishery is considered a Category II fishery because of interactions
with bottlenose dolphins (FR 2010).
The Mid-Atlantic mid-water and bottom trawl fisheries are also considered Category II
fisheries because of their interactions with bottlenose, common and white-sided dolphins
(mid-water also interacts with Risso‟s dolphin), and long and short-finned pilot whales
(FR 2010).
It is also possible that gillnet, trawl and pound net fisheries targeting Weakfish
incidentally capture sea turtles (ASMFC 2002). However, bycatch reduction devices are
now required on trawls, which has reduced these incidental interactions.
3.00
Bycatch in this fishery is low (<10% of targeted landings) and does not regularly include
"threatened, endangered or protected species."
Points of Adjustment (multiple selections allowed)
-0.25 Bycatch in this fishery is a contributing factor to the decline of "threatened,
endangered, or protected species" and no effective measures are being taken to
reduce it.
Bottlenose dolphins are currently considered depleted in the western North Atlantic
coastal waters and the North Atlantic right whale is considered endangered under the
Endangered Species Act (ESA) (NMFS 2010). In addition, all sea turtles in US waters are
endangered or threatened under the ESA (NMFS 2010b). However, the Weakfish fishery
has not been identified specifically as the cause of these population declines, so we have
not subtracted any points.
-0.25 Bycatch of targeted or non-targeted species (e.g., undersize individuals) in this fishery is
high and no measures are being taken to reduce it.
-0.25 Bycatch of this species (e.g., undersize individuals) in other fisheries is high OR bycatch
of this species in other fisheries inhibits its recovery, and no measures are being taken to
reduce it.
-0.25 The continued removal of the bycatch species contributes to its decline.
+0.25 Measures taken over a major portion of the species range have been shown to reduce
bycatch of "threatened, endangered, or protected species" or bycatch rates are no longer
deemed to affect the abundance of the "protected" bycatch species OR no measures
needed because fishery is highly selective (e.g., harpoon; spear).
+0.25 There is bycatch of targeted (e.g., undersize individuals) or non-targeted species in this
fishery and measures (e.g., gear modifications) have been implemented that have been
shown to reduce bycatch over a large portion of the species range OR no measures are
needed because fishery is highly selective (e.g., harpoon; spear).
+0.25 Bycatch of this species in other fisheries is low OR bycatch of this species in other
fisheries inhibits its recovery, but effective measures are being taken to reduce it
over a large portion of the range.
Historically, Weakfish bycatch in shrimp trawls was very high, often exceeding
commercial landings of the species (Nance 1998). However, shrimp trawlers in all states
are now required to use bycatch reduction devices (BRD), which are required to reduce
the incidental capture of a number of species including Weakfish by around 30% overall
(ASMFC 2007; ASMFC 2010b). For example, the, large mesh extended funnel BRDs
have been shown to reduce Weakfish catches by 6-56% and the Florida fisheye BRDs
can reduce interactions by 58% (SAFMC 2004).
Fishermen targeting other species are allowed a Weakfish bycatch limit of 100 lbs (most
states) or 10% of total landings, up to a maximum of 1,000 lbs (NC only) (ASMFC
2010B).
+0.25 The continued removal of the bycatch species in the targeted fishery has had or will
likely have little or no impact on populations of the bycatch species OR there are no
significant bycatch concerns because the fishery is highly selective (e.g., harpoon; spear).
2.25 Points for Bycatch
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