Table of Contents Executive Summary Introduction Life History Fisheries Dependent Data Fisheries Independent Data ASAP Model Projections Biological Reference Points Model Uncertainty Acknowledgements Conclusion References Cited
Northeast Fisheries Science Center Reference Document 13-07
Bluefish 2012 Stock Assessment Updateby Anthony Wood
NOAA, National Marine Fisheries Service, Northeast Fisheries Science Center, 166 Water Street, Woods Hole, MA 02543
Web version posted May 9, 2013Citation: Wood A. 2013. Bluefish 2012 Stock Assessment Update. US Dept Commer, Northeast Fish Sci Cent Ref Doc. 13-07; 32 p. Available from: National Marine Fisheries Service, 166 Water Street, Woods Hole, MA 02543-1026, or online at http://www.nefsc.noaa.gov/nefsc/publications/
Information Quality Act Compliance: In accordance with section 515 of Public Law 106-554, the Northeast Fisheries Science Center completed both technical and policy reviews for this report. These predissemination reviews are on file at the NEFSC Editorial Office.
The updated stock assessment was completed by adding catch and indices through 2011 to the previous 1982-2010 assessment. Catch information consisted of commercial landings and length frequencies from Maine to Virginia collected by the Northeast Fisheries Science Center, North Carolina landings and length information collected by NC Division of Marine Fisheries, Florida landings and length information collected by FL Fish and Wildlife Research Institute, and recreational landings and discards from Maine to Florida collected in the NMFS recreational fisheries survey. The catch data were combined with fisheries-independent survey data from the Northeast Fisheries Science Center, DE DNR, NJ DEP, CT DEP, coast-wide recreational catch per angler, as well as juvenile indices from the SEAMAP program in the South Atlantic, in a forward projecting catch-at-age model (ASAP). Fishery-dependent and independent information was partitioned into ages using a 2011 age-length key developed by Old Dominion University supplemented with additional age information from MA DMF and NC DMF.
Results of the analyses show that bluefish are not overfished or experiencing overfishing. Fishing mortality in 2011 was 0.114, below the biological reference point (FMSY) of 0.19. Fishing mortality steadily declined from 0.34 in 1987 to 0.12 in 1999 and has remained steady since 2000 with an average F=0.138. Recent total stock biomass estimates peaked in 1982 at 338.0 thousand MT, then declined to 77.7 thousand MT by 1996 before increasing steadily to the 136.4 thousand MT in 2010 and slightly declining again to 132.9 thousand MT in 2011. Recruitment estimated in the ASAP model has remained relatively constant since 2002 at around 20 million age-0 bluefish, with the exception of a relatively large 2006 cohort estimated as 35.1 million fish. However, the 2010 and 2011 recruitment estimates were well below average at 14.6 and 10.6 million fish, respectively. There was no significant retrospective bias in the results. A projection of the abundance through 2014, under five different fishing scenarios between F=0.10 and F=0.19, suggest that biomass will continue to decline due to poor incoming year classes. Changes in the NMFS survey, limited age information, discard size data and model configuration all contribute to the uncertainty in the assessment.
The Atlantic coast stock of bluefish (Pomatomus saltatrix), distributed from Maine through eastern Florida, is jointly managed by the Atlantic States Marine Fisheries Commission (ASMFC) and the Mid-Atlantic Fishery Management Council (MAFMC). A total annual quota is established and allocations given to commercial and recreational fisheries. The management plan requires a distribution of 80% to recreational and 20% to commercial, with provisions to shift unused recreational quota to commercial fisheries.
A bluefish stock assessment was presented for peer-review at the Northeast Fisheries Science Center Stock Assessment Review Committee meeting (NEFSC SARC 41). The reviewers accepted the assessment for use in management decisions although there were some reservations about the modeling approach. Since the review, the bluefish stock assessment sub-committee (SASC) has produced annual updates while maintaining the basic model settings from the approved assessment. The current assessment is a continuation of the model update with the addition of 2011 catch at age and indices at age information.
Bluefish, Pomatomus saltatrix, is a coastal, pelagic species found in temperate and tropical marine waters throughout the world (Goodbred and Graves 1996; Juanes et al. 1996). Bluefish spawn in offshore waters (Kendall and Walford 1979; Kendall and Naplin 1981). Larvae develop into juveniles in continental shelf waters and eventually move to estuarine and nearshore shelf habitats (Marks and Conover 1993; Hare and Cowen 1994; Able and Fahay 1998; Able et al. 2003). Bluefish are highly migratory along the U.S. Atlantic coast and seasonally move between the
U.S.south Atlantic and Middle-Atlantic, traveling as far north as Maine (Shepherd et al., 2006).
Several studies show bluefish to be a moderately long-lived fish with a maximum age of 14 years (Hamer 1959; Lassiter 1962; Richards 1976; Barger 1990; Chiarella and Conover 1990; Terceiro and Ross 1993; Austin et al. 1999; Salerno et al. 2001; Sipe and Chittenden 2002). Bluefish up to 88 centimeter (cm) fork length (FL) have been aged (Chiarella and Conover 1990; Salerno et al. 2001), although Terceiro and Ross (1993) noted considerable variation in mean bluefish size-at-age. Scale ages have been used to estimate von Bertalanffy growth parameters (Lassiter 1962; Barger 1990; Terceiro and Ross 1993; Salerno et al. 2001). The values for L∞ from these studies (87-128 cm FL) match closely to the largest individuals in catch data and growth rates do not differ between sexes (Hamer 1959; Salerno et al. 2001).
Bluefish grow nearly one-third of their maximum length in their first year (Richards 1976, Wilk 1977). Variation in growth rates or sizes-at-age among young bluefish is evident from the appearance of intra-annual cohorts. Lassiter (1962) identified a spring-spawned cohort and a summer-spawned cohort from the bimodal appearance of size at Annulus I for fish aged from
North Carolina and the seasonal cohorts can differ in age by two to three months. Summer-spawned larvae and juveniles grow faster than spring-spawned larvae and juveniles (McBride and Conover 1991) although size differences at annual age diminish greatly after three to four years (Lassiter 1962).
Spawning occurs offshore in the western North Atlantic Ocean, from approximately
Massachusetts to Florida (Norcross et al. 1974; Kendall and Walford 1979; Kendall and Naplin 1981; Collins and Stender 1987). Bluefish are characterized as multiple spawners with indeterminate fecundity which spawn continuously during their spring migration (Robillard et al. 2008). In addition to distinctive spring and summer cohorts, Collins and Stender (1987) identified a fall-spawned cohort, demonstrating the potential of an extended bluefish spawning season.
Bluefish in the western
North Atlantic are managed as a single stock (NEFSC 1997; Shepherd and Packer 2006). Genetic data support a unit stock hypothesis (Graves et al. 1992; Goodbred and Graves 1996; Davidson 2002). For management purposes, the ASMFC and MAFMC define the management unit as the portion of the stock occurring along the Atlantic Coast from Maine to the east coast of Florida.
Annual catch information was developed for five components of the commercial fishery. Commercial landings from Maine to Virginia, North Carolina commercial landings, Florida commercial landings, coast-wide recreational landings and coast-wide recreational discards.
Commercial fisheries from Maine to Virginia were sampled as part of the NEFSC data collection program. Lengths were sampled from a variety of gears and market categories. Expansion of length data was completed by market category and quarter of the year, with the results merged into half year periods. In 2011 a total of 6,342 measurements were collected across all market categories from total landings of 1,482 mt (60% of all commercial landings; Table 1). Market category/quarter with inadequate length samples were filled with length information from adjacent quarters within the same market category or from NC samples if necessary.
North Carolina commercial landings were expanded using length samples collected by NC Division of Marine Fisheries. A total of 1,186 measurements were collected from landings of 862 mt (Table 1). Expansion of landings at length were done by quarter, market category and gear type then combined into half year totals. Length samples from Florida 2011 commercial landings were also available. A total of 237 lengths were used to expand commercial landings of 111 mt (Table 1). No landings were reported for
South Carolina or . Total coast-wide commercial landings in 2011 were 2,455 mt, a decrease of 751 mt from 2010 (Figure 1). Georgia
Length frequencies from commercial fisheries are characterized by a multi-modal distribution (Figure 2). In 2011 the distribution was strongly bimodal with one peak at 38 cm and a second around 72 cm.
Recreational landings are sampled for length as part of the MRIP program. The 2011 recreational landings were 5,965 mt, a decrease from 8,184 mt in 2010 (Table 2, Figure 3). The MRIP 2011 length samples were used to expand recreational landings per half year. Recreational discards in 2011 were estimated at 16,860 mt, however after adjusting for a 15% mortality rate, the resulting discard loss was 2,529 mt. A recent publication (Fabrizio et al 2008) shows that mortality may be higher and the 15% should be reevaluated in the next benchmark assessment. Length sampling of bluefish tagged and released in the American Littoral Society tagging program (by definition B2 catches) were included in the length distribution (n=561). Length frequencies from the recreational catch and discards are characterized by a bimodal distribution, similar to the observed distribution of the commercial length frequency (Figure 4). Total combined (commercial and recreational) length frequencies are presented in Figure 5.
Age data were provided by Virginia Marine Resources Commission and Old Dominion University ageing lab (n = 481), MA DMF (n = 69), and NC DMF provided ages for fish over 50 cm (n = 45). Since the age key developed from these data was the only 2011 age information available, it was applied to both fishery dependent and independent length data.
The length frequencies by age were converted to weight for calculation of annual weights at age (Table 3 Figure 6). Length-weight equations from the spring and fall NEFSC bottom trawl survey were used for calculating weights at age. Due to low sample size in spring surveys, all years beginning with 1992 were used in the equation (n=248, a = -11.357, b = 3.003). Fall equations were estimated from combined 2004-2011 length-weight data (n = 3596, a = -11.610, b = 3.093).
The 2011 catch at age is presented in Table 4. As in previous bluefish assessments the ages are summarized in a plus category for ages 6 and above to reduce the effect of aging error.
Survey indices as used in the previous bluefish assessment were updated for 2011. These indices include SEAMAP juvenile (age 1) indices, Northeast Fisheries Science Center (NEFSC) bottom trawl survey indices for ages 0 to 6+, NJ bottom trawl survey indices of ages 0 to 2, DE bottom trawl survey indices for ages 0 to 2 and Marine Recreational Information Program (MRIP) recreational catch per angler trip (CPA) for ages 0 to 6+. The CT survey in 2008 and 2010 were not conducted during the month of September, therefore these indices were treated as missing data. The NEFSC survey in 2009 was modified by the replacement of the FV Albatross IV with the FSV Henry B. Bigelow. The consequence of the replacement was a change in the areas surveyed and the efficiency of the survey due to a change in net size and towing speed (as well as other intangibles associated with a different vessel). Beginning in 2009 only the outer third of the inshore strata set was sampled by the Bigelow. In addition, a conversion coefficient of 1.16 was used to convert Bigelow mean number per tow into equivalent Albatross units (Miller et al., 2010).
Among these survey indices, there were no consistent trends in total abundance. The total NEFSC index (ln re-transformed stratified mean number per tow) declined from 38.05 in 2006 to 6.66 in 2010, and slightly increased to 7.45 in 2011 (Table 5). The series arithmetic average index equaled 25.9 (geometric mean of 13.6). The 2011 Delaware survey index of ages 0 to 2 was 0.2 fish per tow, and below the time series average (0.51 per tow; Table 6). New Jersey trawl survey indices of ages 0 to 2 for 2010 (14.37 fish/tow) was well above the time series average of 6.6 per tow (Table 6). In the 2010 bluefish update assessment there was an error in the NJ index resulting from an incorrect tally of the raw survey data. This error has been corrected for both 2010 and 2011 data for this update. Connecticut DEP survey data were unavailable for 2010 but the index for 2011 was 12.93, lower than the mean of 32.8 (Table 7). Recreational catch per angler trip showed a small increase to 0.401 fish per angler trip in 2011, an increase from 0.361 in 2010 (Table 8). The recreational catch per angler was modeled in a generalized linear model using a negative binomial error structure. The year coefficient partitioned into ages (assuming the same proportion as the recreational catch) was used in the ASAP model as a relative index of abundance.
The ASAP model (version 2.0.20) was run as an update of previous 1982-2010 input file, updated for 2011 total catch, catch at age, weight at age and indices at age. The fishery was modeled as a single fleet with selectivity fixed as a bimodal pattern with full recruitment at age 1 (coded age 2). Model weighting factors remained the same as previous assessments with the model heavily weighted towards the fishery total catch rather than survey indices. Natural mortality was fixed at 0.2 and maturity at age was held constant with full maturity at age 3. The updated model was run using the same parameter settings while substituting the updated catch and weight at age matrices.
The results of the updated ASAP model showed a decrease in total abundance since 2006, declining from 94.4 million to 66.3 million fish (Table 9, Figure 7). The decline is primarily the result of poor 2009, 2010, and 2011 year classes. Prior to 2009 recruitment had remained relatively constant since 2000 at 21.4 million age-0 bluefish, with the exception of a large 2006 cohort estimated as 37.3 million fish. The 2009 recruitment estimate was below average at 12.5 million fish compared to the series average of 22.8 million, and low recruitment persisted for 2010 and 2011 (Table 9, Figure 8). Estimated recruitment in 2011 was the lowest in the time series at 10.6 million. However among other age groups, the estimate of age 6-plus bluefish continued to be large at 12.8 million, the highest since 1990. Total mean biomass in 2011 equaled 132,890 mt, a slight decrease from the 2010 estimate of 136,371 mt (Table 10, Figure 9). Corresponding spawning stock biomass (SSB) in 2011 was 123,107 mt, also a slight decrease from the 2010 estimate of 124,601 mt (Figure 9).
Fishing mortality estimates in ASAP are based on a separability assumption with F at age the product of FMULT and selectivity. Full selectivity is fixed at age 1. The 2011 FMULT value equals 0.114 (Figure 7). Fishing mortality steadily declined from 0.34 in 1987 to 0.12 in 1999 and has remained steady since 2000 with an average F=0.14.
Retrospective bias for the final model was examined for F, total abundance, recruitment (age 0) and total biomass. The analysis shows little evidence of bias in the estimates (Figure 10). The variation in the final model results for F and SSB was determined using a Monte Carlo Markov chain with 1000 iterations and a thinning factor of 100. The MCMC results of variation around F ranged from 0.096 to 0.134, with the 80% CI between 0.106 and 0.123. Estimates for SSB ranged from 101,800 to 143,400 mt, with an 80% CI between 115,632 mt and 133,207 mt. (Figure 11).
Bluefish abundance and biomass through 2014 were examined for a range of fishing scenarios with a stochastic projection in AGEPRO software. Weight-at-age in 2012-2014 was assumed equal to 2011, recruitment was derived from a random draw of 28 empirical estimates of age 0 abundance since 1982 and initial population size was drawn from the output of the MCMC run. Fishing quota for 2012 was set equal to the ACL of 14,535 mt. Five projection scenarios were examined: F =0.10, F=status quo (0.114), Ftarget (0.17) which equals 90% of FMSY as defined in FMP, F0.1 (0.16) from the yield per recruit, and FMSY (0.19).
Results of the projections show a decrease in mean biomass and SSB for each scenario including a reduced F (F=0.10) (Table 11). However, abundance continued to increase in all 5 cases. Yield through 2014 would be projected as lower for F scenarios of status quo or less. Under status quo F (0.114), projected 2013 yield would decrease to 10,840 mt, which includes commercial and recreational landings as well as recreational discards losses.
The current biological reference points for bluefish, determined in SARC 41 are FMSY (0.19) and BMSY (147,052 mt). The basis for the reference points was the Sissenwine-Shepherd method using the Beverton-Holt stock recruitment parameters and SSB per recruit results generated by the SARC 41 ASAP model results. BMSY was calculated using mean weights at age and is therefore comparable to mean biomass in year t. The 2011 estimate of mean total biomass is 132,890 mt (+1 std. dev. of 7,433 mt), is slightly below BMSY but well above 1/2 BMSY of 73,526 mt. The 2011 estimate of fishing mortality (0.114) remains below FMSY.
Model uncertainty can be characterized using Markov Chain Monte Carlo (MCMC) simulations to produce a distribution of possible outcomes given the model input parameters. However, these results do not capture the uncertainty from variations in the model input parameters. Forward projecting catch at age models are extremely flexible in applying weighting factors to emphasize either catch data or survey data. To illustrate the impact of changes to these weightings, as well as other factors, an ASAP model was run with changes to the effective sample size, and changes to index lambdas and CVs to force the model to fit closer to the annual indices (Table 12). The resulting fishing mortality in 2011 was 0.14 with an SSB estimate of 101,533 mt, slightly outside the 80% confidence interval associated with the MCMC simulation for the base model.
The conclusion of the updated assessment is that the Atlantic coast bluefish stock continues below BMSY while remaining below FMSY and is not considered overfished or experiencing overfishing. The estimates of the model show little variation or significant retrospective patterns. The lack of variation is due in part to the fixed parameters for selectivity. Nevertheless, uncertainty remains in several aspects of the assessment input data. Age data continue to be limited to one age key built from a limited set of samples. The assumption that this age information is applicable to all areas remains untested. Length samples from recreational discards are limited and contribute to the uncertainty as does the lack of commercial discard estimates. Changes in the NEFSC inshore survey series, from both vessel changes and sample area adjustments, significantly alter indices. Strata inshore of 15 fathoms are currently sampled as part of the NEMAP survey, but the time series is not yet adequate to provide a tuning index.
The highly migratory nature of bluefish populations and the recruitment dynamics of the species create a unique modeling situation. Migration creates seasonal fisheries with unique selectivity patterns resulting in a bimodal partial recruitment pattern. This pattern has been identified in previous assessments as a source of uncertainty in the results and has been held constant in the model. The migratory pattern in bluefish also results in several recruitment events. A spring cohort, originating south of Cape Hatteras, NC during spring migrations, and a summer cohort originating in the offshore Mid-Atlantic Bight result in a bimodal age-0 size distribution. It has been hypothesized that the success of the spring cohort controls the abundance of adult bluefish. Future assessments should include any additional information that could index seasonal abundance of incoming recruitment.
Thanks to Gary Shepherd for his help and guidance towards completing the assessment and to the rest of the Coastal Pelagic Working Group members who contributed advice and expertise during the assessment process. Also, thank you to the age and growth laboratories of Old Dominion University, MA DMF, and NC DMF for providing the necessary age data for these analyses.
Able, K.W. and M.P. Fahay. 1998. The First Year in the Life of Estuarine Fishes in the Middle Atlantic Bight. Rutgers University Press.
New Brunswick, NJ.
Able, K.W., P. Rowe, M. Burlas, and D. Byrne. 2003. Use of ocean and estuarine habitats by young of the year bluefish (Pomatomus saltatrix) in the New York Bight. Fishery Bulletin 101:201-214.
Austin, H.M., D. Scoles, and A.J. Abell. 1999. Morphometric separation of annual cohorts within Mid-Atlantic bluefish, Pomatomus saltatrix, using discriminant function analysis. Fishery Bulletin 97:411-420.
Barger, L.E. 1990. Age and growth of bluefish Pomatomus saltatrix from the northern Gulf of Mexico and U.S. South Atlantic coast. Fishery Bulletin 88:805-809.
Beaumariage, D.S. 1969. Returns from the 1965 Schlitz tagging program including a cumulative analysis of previous results. Florida Dept. of Natural Resources, Marine Research Lab Technical Series No. 59:1-38.
Chiarella, L.A. and D.O. Conover. 1990. Spawning season and first year growth of adult bluefish from the New York Bight. Transactions of the American Fisheries Society 119:455-462.
Chittenden Jr., M.E., L.R. Barbieri, C.M. Jones, and S.J. Bobko. 1990. Initial information on the Atlantic croaker, annual report on the development of age determination methods, life history - population dynamics information and evaluation of growth overfishing potential for important recreational fishes. April. Submitted to the Virginia Marine Resources Commission. 88 p.
Collins, M.R. and B.W. Stender. 1987. Larval king mackerel (Scomberomorus cavalla), Spanish mackerel (S. maculatus), and bluefish (Pomatomus saltatrix) off the southeast coast of the United States, 1973-1980. Bulletin of Marine Science 41:822-834.
Davidson, W.R. 2002. Population structure of western Atlantic bluefish (Pomatomus saltatrix). Master's Thesis. Thesis.
University of Delaware., Wilmington, DE.
Fabrizio, M.C., F.S. Scharf, G.R. Shepherd, and J.E. Rosendale. 2008. Factors affecting catch-and-release mortality of bluefish. North Am. J. of Fisheries Management 28:533-546.
Goodbred, C.O. and J.E. Graves. 1996. Genetic relationships among geographically isolated populations of bluefish (Pomatomus saltatrix). Marine and Freshwater Research 47:347-355.
Graves, J.E., J.R. McDowell, A.M. Beardsley, and D.R. Scoles. 1992. Stock structure of the bluefish Pomatomus saltatrix along the Mid-Atlantic coast. Fishery Bulletin 90:703-710.
Hamer, P.E. 1959. Age and growth studies of the bluefish (Pomatomus saltatrix Linnaeus) of the New York Bight. Master's Thesis. Rutgers University, New Brunswick, NJ.
Hare, J.A. and R.K. Cowen. 1995. Effect of age, growth rate, and ontogeny on the otolith size -- fish size relationship in bluefish Pomatomus saltatrix, and the implications for back-calculation of size in fish early life history stages. Canadian Journal of Fisheries and Aquatic Science 52:1909-1922.
Juanes, F., J.A. Hare, and A.G. Miskiewicz. 1996. Comparing early life history strategies of Pomatomus saltatrix: a global approach. Marine and Freshwater Research 47:365-379.
Kendall, A.W.J. and L.A. Walford. 1979. Sources and distribution of bluefish, Pomatomus saltatrix, larvae and juveniles off the east coast of the
United States. Fishery Bulletin 77:213-227.
Kendall, A.W.J. and N.A. Naplin.1981. Diel-depth distribution of summer ichthyoplankton in the Middle Atlantic Bight. Fishery Bulletin 79:705-726.
Lassiter, R.R. 1962. Life history aspects of the bluefish, Pomatomus saltatrix, larvae and juveniles off the east coast of the United States. Fishery Bulletin 77: 213-227.
Lund, W.A. and G.C. Maltezos. 1970. Movements and migrations of the bluefish, Pomatomus saltatrix, tagged in waters of
New York and Southern New England. Transactions of the American Fisheries Society 99:719-725.
Marks, R.E. and D.O. Conover. 1993. Ontogenetic shift in the diet of young-of-the-year bluefish Pomatomus saltatrix during the oceanic phase of the early life history. Fishery Bulletin 91:97-106.
McBride, R.S. and D.O. Conover. 1991. Recruitment of young-of-the-year bluefish Pomatomus saltatrix to the New York Bight: variation in abundance and growth of spring- and summer-spawned cohorts. Marine Ecology Progress Series 78:205-216.
Miller, T.J., C. Das, P.J. Politis, A.S. Miller, S.M. Lucey, C.M. Legault, R.W. Brown, and P.J. Rago. 2010. Estimation of Albatross IV to Henry B. Bigelow calibration factors. NEFSC Ref. Doc. CRD 10-05.
Norcross, J.J., S.L. Richardson, W. H. Massmann, and E.B. Joseph. 1974. Development of young bluefish (Pomatomus saltatrix) and distribution of eggs and young in Virginian coastal waters. Transactions of the American Fisheries Society 103:477-497.
Northeast Fisheries Science Center. 1997. Report of the 23rd Northeast Regional Stock Assessment Workshop (23rd SAW): Stock Assessment Review Committee (SARC) consensus summary of assessments. NEFSC Reference Document 97-05.
Northeast Fisheries Science Center. 2005. Report of the 41st Northeast Regional Stock Assessment Workshop (41st SAW): 41st SAW Assessment Report NEFSC CRD 05-14. September, 2005. 237 pp. 97-05.
Richards, S.W. 1976. Age, growth, and food of bluefish (Pomatomus saltatrix) from East-Central Long Island Sound from July through November 1975. Transactions of the American Fisheries Society 105:523-525.
Robillard, E., C.S. Reiss, C.M. Jones. 2008. Reproductive biology of bluefish (Pomatomus saltatrix) along the East Coast of the United States. Fisheries Research 90 (2008): 198-208.
Salerno, D.J., J. Burnett and R.M. Ibara. 2001. Age, growth, maturity, and spatial distribution ofbluefish, Pomatomus saltatrix, off the northeast coast of the United States, 1985 - 96. Journal of
Northwest Atlantic Fishery Science 29:31-39.
Sipe, A.M. and M.E. Chittenden Jr. 2002. A comparison of calcified structures for ageing bluefish in the Chesapeake Bay region. Transactions of the American Fisheries Society 131:783-790.
Shepherd, G.R., J. Moser, D. Deuel, P. Carlson. 2006. The migration patterns of bluefish (Pomatomus saltatrix) along the Atlantic coast determined from tag recoveries. Fish. Bull. 104:559-570.
Shepherd, G.R. and D. B. Packer. 2006. Essential Fish Habitat Source Document: Bluefish, Pomatomus saltatrix, Life History and Habitat Characteristics 2nd edition. NOAA Technical Memorandum, NMFS-NE-198:100.
Terceiro, M. and J.L. Ross. 1993. A comparison of alternative methods for the estimation of age from length data for Atlantic coast bluefish. Fishery Bulletin 91:534-549.
Wilk, S.J. 1977. Biological and fisheries data on bluefish, Pomatomus saltatrix (Linnaeus). NOAA, NMFS, NEFC,
Sandy Hook Lab. Technical Series Report. No. 11.