Black Sea Bass (U.S. Mid-Atlantic)

Black Sea Bass/By Robert Shetterly © Blue Ocean Institute

Centropristis striata

Sometimes known as Black Bass, Black Perch, Blackfish, Black-Harry, Black-Will, Bluefish, Hannahhill, Rock Bass or Tailywag (or Tally-wag).

This species is wild-caught.

Summary

Black sea bass in the Mid-Atlantic are commonly caught among rocky structures by both recreational and commercial fishers. They begin life as females and become males by the time they're five years old, a characteristic that has the potential to increase their vulnerability to fishing pressure. However, stronger management in recent years is helping Black sea bass recover and they're no longer overfished. The level of bycatch is unknown.

Criterion	Points
Life History	2.50
Abundance	2.25
Habitat Quality and Fishing Gear Impacts	1.50
Management	3.25
Bycatch	2.25
Final Score (average of criteria)	2.35
Color

Final Score	Color
2.60 - 4.00
2.20 - 2.59
1.80 - 2.19
1.40 - 1.79
0.00 - 1.39

Last updated March 14, 2005.

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. Intrinsic rate of increase is unknown. Black sea bass mature between 1 and 4 years of age, with 50% of the population mature by age 2 (MAFMC 2002). Maximum age is 15 years (ASMFC 2000).

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.).
-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). Black sea bass are protogynous hermaphrodites, beginning life as females and changing to males between 2 and 5 years of age (ASMFC 2000).
-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). Black seabass are distributed on the continental shelf of the Western Atlantic from Maine to northeastern Florida and in the eastern Gulf of Mexico. During cold winters, the range extends to the southernmost portion of Florida (Fishbase 6/4/02). There are three populations of Black sea bass: northern (north of Cape Hatteras), southern (Cape Hatteras to Florida) and the Gulf of Mexico. Overall, we consider these populations to extend over a small range, compared to other more wide-ranging species.
-0.25	Species exhibits high natural population variability driven by broad–scale environmental change (e.g., El Nino; decadal oscillations).

+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).
+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).

2.50	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).
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. The most recent stock assessment for the northern population of Black sea bass did not estimate MSY or BMSY. Instead, it looked at biomass per tow for fish greater than or equal to 22 cm from the spring survey conducted by the Northeast Fisheries Science Center. The biomass index for 2002-2004 was 0.94 kg/tow, which is above the 1/2 BMSY proxy. Thus, Black sea bass are no longer considered overfished, as they were in the 1998 assessment. However, the population is not yet fully rebuilt (NMFS 2004).
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).
-0.25	Age, size or sex distribution is skewed relative to the natural condition (e.g., truncated size/age structure or anomalous sex distribution). The stock assessment for the northern population of Black sea bass does not include age data, and therefore does not draw any conclusions about the age distribution of the population. There is no conclusive evidence about the health of the sex distribution. Studies showing the presence of large females may imply that there are adequate numbers of dominant males. Another indicator of a healthy sex distribution would be the continued production of good year classes. However, it's too early to tell if the recent juvenile indices will translate into adult biomass (Shepherd, Pers. Comm. 2004). Due to the lack of adequate information, no points were subtracted or added for this factor.
-0.25	Species is listed as “overfished” OR species is listed as “depleted”, “endangered”, or “threatened” by recognized national or international bodies.
-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.

+0.25	The population is increasing over a generational time scale (as indicated by biomass estimates or standardized CPUE). Total biomass of the northern population of Black sea bass has increased substantially since 1998. There have been some declines in total biomass from 2003 to 2004, however. Exploitable biomass (fish greater than or equal to 22 cm) has also increased since 1998, although it has declined in 2003 and 2004 from 2002 levels. Overall, the population appears to be following an increasing trend, as demonstrated by the fact that the population is no longer overfished. However, NMFS recommends that managers be cautious in setting quotas (NMFS 2004).
+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.

2.25	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). The majority of commercial fisheries for Black sea bass occur in Massachusetts, New Jersey, Virgina, and Maryland. In 2002-2003 these fisheries used the following gear types: pots (42%), otter trawl (40%), and hook and line (12%). Otter Trawl fisheries may use roller rigs or rock hopping gear (NMFS 2004). We awarded a middle score of 2 here because the majority of landings (total of 54% from pots and hook and line) are taken with gear that has a low or moderate effect on habitat.
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).
-0.25	Critical habitat areas (e.g., spawning areas) for this species are not protected by management using time/area closures, marine reserves, etc. Estuaries are important habitat for Black sea bass. Many states restrict trawling in some estuaries to help protect habitat. However, many areas identified as important habitat are not being protected. Amendment 13 to the Summer Flounder, Scup, and Black sea bass Fishery Management Plan presented an Essential Fish Habitat Alternative management measure that would prohibit bottom tending mobile gear in nearshore areas of Albermarle Sound, Chesapeake Bay, Delaware Bay and New York Harbor. But this alternative was not accepted (MAFMC 2002). Points were subtracted here to account for inadequate protection of many estuaries.
-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). Roller rigs and rockhopping gear are used in trawl fisheries targeting Black sea bass. However, restictions are in place to minimize impacts on habitat. For example, rollers on roller rig trawl gear and rock hopper trawl gear cannot be greater than 18 inches. This restriction means that certain areas cannot be trawled. Additionally, street sweeper gear is prohibited in an effort to protect structured habitat (MAFMC 2002). No points were subtracted here to account for the effort to reduce the impact of this potentially harmful gear type.
-0.25	If gear impacts are substantial, resilience of affected habitats is very slow (e.g., deep water corals; rocky bottoms). Although Mid-Atlantic habitat is characterized as dynamic sandy bottom, Black sea bass require structure. Juveniles are found in greatest abundance in clay outcrops where burrowing crabs create holes in the clay or in areas with empty surf clam shells and other small scale structure. Adults use larger structures such as mussel beds, offshore rocky habitats, and sunken ships (Witting, Pers. Comm 2004). Gear impacts could be more severe among these structures.

+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.

1.50	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.
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. Black sea bass are jointly managed by the Atlantic States Marine Fisheries Commission (ASMFC) and the Mid-Atlantic Fishery Management Council (MAFMC). Management measures include gear-type controls, quotas, minimum size restrictions, trip limits, and permits. Prior to December 2002, the fishery was managed coastwide on a quarterly system, whereby quotas were divided among different quarters of the year. Under this system, there were serious problems with fishers exceeding their quotas and racing to fish. In December 2002, the ASMFC implemented a new system whereby each state has a share in the total coastwide quota and each state can decide how to regulate its fisheries. For example, some states are managing their fisheries under an ITQ system. This system is considered a major improvement because there is no longer a race for fish. However, landings to date show that in 2003, most states exceeded their quotas (MAFMC 2004). Still, despite this problem, management is demonstrating success. The northern population of Black sea bass is no longer overfished and overfishing is not occurring (NMFS 2004).

Points of Adjustment (multiple selections allowed)

-0.25	There is inadequate scientific monitoring of stock status, catch or fishing effort. There is currently no comprehensive assessment of the Black sea bass population. Although the NEFSC conducts a spring survey and uses survey data to create a proxy for MSY, scientific monitoring of the population status needs substantial improvement.
-0.25	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.
+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. A recovery plan is in place for Black sea bass that is showing signs of success. The northern population is no longer considered overfished (NMFS 2004).
+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. The Black sea bass fishery is no longer considered overcapitalized. Under the new management system, whereby states have shares of the coast-wide quota, some states have implemented systems such as ITQs to deal with overcapitalization (Kerns, Pers. Comm. 2004).

3.25	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. Since 1989, managers have been using an observer program to collect information on discards, including Black sea bass. However, managers have not extrapolated enough for the entire fleet to get a comprehensive assessment of bycatch in fisheries that catch Black sea bass (NMFS 2004).
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.
-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). Escape vents are required for pot/trap gear to allow undersize fish to exit traps. In 2002 fishery managers changed the required vent size to accomodate changes in the new minimum size for Black sea bass (11 inches; previously was 9 inches) (MAFMC 2004). This demonstrates that management is working to minimize catch of undersize fish even though the full extent of bycatch has not been quantified.
+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.
+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

References

Atlantic States Marine Fisheries Commission. Robert Beal. November 2000. Review of the Atlantic States Marine Fisheries Commission Fishery Management Plan for Black Sea Bass (Centropristis striata).

Fishbase. June 4, 2002. Online at : http://www.fishbase.org/Summary/SpeciesSummary.cfm?genusname=Centropristis&speciesname=striata

Kerns, Toni. Atlantic States Marine Fisheries Commission. 2004. Personal Communication.

Mid-Atlantic Fishery Management Council. 2004. Memo from Chris Moore to the Black Sea Bass Monitoring Committee on Black Sea Bass Management Measures.

Mid-Atlantic Fishery Management Council. August 2002. Amendment 13 to the Summer Flounder, Scup, and Black Seabass Fishery Management Plan.

National Marine Fisheries Service. SAW Coastal/Pelagic Working Group. May 4, 2004. Assessment of the Northern Stock of Black Sea bass. SARC 39, Consensus Assessment Report.

Seafood Handbook. 2002. Diversified Business Communications. Portland, ME.

Shepherd, Gary. 2004. Woods Hole Oceanographic Institute. Personal Communication.

Witting, David. 2004. NOAA. Personal Communication.