Fisheries Independent/SCUBA Assessment Project -- Website Update February, 2012

From the “What we do” link:

Fisheries Independent/Scuba Assessment Project

Project staff uses scuba-based and other fishery-independent methods including SCUBA to gather fish and invertebratefishery-releveant data from nearshore environments. The project goal is to provide information to improve management of nearshore resources. Staff activities include data collection for stock assessments,

evaluation of marine protected areas, monitoring of important fished species and their habitats, and determination of life-history parameters for various species. Scuba AssessmentFisheries Independent

Assessment Project staff often work collaboratively with other agencies, academic institutions, and the fishing community on large-scale monitoring and research efforts.

Enter the Fisheries Independent /Scuba Assessment Project website

Text from the above page:

Both fishery-dependent and fishery-independent data are used to make informed management decisions regarding marine resources. Fishery-dependent data rely on direct observations of the fishery through market

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sampling, on-board observer programs, landing receipts, and logbooks. Fishery-independent data, on the other hand, rely on direct observations of species, populations, and ecosystems.

Fishery-independent data are collected using a variety of methods and equipment. Fishing surveys (trawls or other nets), underwater surveys (scuba), and mark-recapture efforts (tags) are often used to collect information. Fishery-independent methods collect standardized information from all life stages of a species, not just information that is marketable or utilized by a fishery.

Fishery-independent research and monitoring often collects essential fishery information (or "EFI"). EFI is information about the biology, ecology and harvest of a fish species, and is important for sustainable fisheries management. Some examples of EFI include indices of abundance, total mortality, movement patterns, spawning behavior, fecundity, reproductive potential, age, and growth.

Fishery-independent data are collected using a variety of methods and equipment. Fishing surveys (trawls or other nets), underwater surveys (SCUBA), and mark-recapture efforts (tags) are often used to collect information. Fishery-independent methods collect standardized information onfrom all life stages of a species, not just information that ison species that are marketable or utilized by a fishery.

The Fisheries Independent/Scuba Assessment pProject staff work in southern California (Los Alamitos), and central California (Monterey). The southern California staff is currently studying abundance and movement patterns of surf fishes in the Southern California Bight, and habitat characteristics and movement patterns of barred sand bass. In addition, they are also characterizing hormonal changes in barred sand bass related to gonad development and to exogenous environmental cues and they are developing an estimate of spawning frequency. The central California staff is currently studying abundance, mortality and movements of nearshore fishes within Carmel Bay, including the Carmel Pinnacles State Marine Reserve; kelp greenling age, growth, and maturity; and age validation for cabezon and kelp greenling. The central California staff also provides oversight for, coordinates, and administers the DFG Diving Safety Program.

Go to “barred sand bass” in “Current Studies” tab

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Barred sand bass text from the above page:

Barred Sand Bass Spawning Movements and Habitat Characterization

Background

Barred sand bass, Paralabrax nebulifer, continues to be one of the most sought-after sport fish in southern California. Since the 1960s, this species has ranked among the top ten sport fish caught by commercial passenger fishing vessels (CPFVs), or "party boats," in southern California, with annual catches averaging nearly one million fish over the last 20 years. For decades, CPFVs and private recreational boaters have targeted well-known spawning aggregation sites throughout southern California, including the Ventura Flats, Santa Monica Bay, Huntington Beach Flats, San Onofre, and San Diego. Approximately 71 percent of the annual barred sand bass catch is harvested by the CPFV fleet from June through August, during peak spawning season.

From 1961 to 2008, barred sand bass catches increased to a high in 2000 and have dramatically declined since. These dramatic catch declines in recent years have caused concern among fisheries biologists and fishermen alike. A recent fishery analysis on the basses (including barred sand bass) was conducted in 2010-11 and it appears that bass populations in the last decade have been negatively affected by cool oceanographic conditions and fishing. Answering questions regarding barred sand bass spawning behavior, movements and spawning habitat requirements will be important for the management of this resource.

Fishery analysis on the basses in southern California (LINK here to MRC basses pdf)

"Hotspot" Analysis

Barred sand bass catch location data was compiled by California Recreational Fisheries Survey (CRFS) samplers for private/rental boats from 2004-2008 in the southern California region. CRFS samplers interview anglers at public launch facilities, asking questions about their fishing activities, examining their catch to determine the number and species of fish kept or discarded, weighing and measuring the catch, and collecting fishing location and depth information. The catch location data were mapped and analyzed using a Geographic

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Information System (GIS) and major "hotspot" catch locations (potential spawning grounds) were identified. This analysis provides valuable information about where and when barred sand bass spawning aggregations may occur in southern California. In addition, areas fished around Huntington Beach were examined on a finer scale to examine any seasonal patterns of catch.

Spawning Movements

In the 1960s and 1990s, biologists with the DFG tagged a total of 9,000 barred sand bass in southern California. The recapture information from these two time periods enabled us to document large-scale spawning-related movements of barred sand bass for the first time. Using this dataset we have attempted to discover 1) how long individual barred sand bass remain at spawning grounds during spawning season, 2) how far fish migrate to spawn, and 3) whether fish show fidelity to certain spawning locations.

In addition to large-scale spawning movements, we were also interested in the short-term, fine-scale spawning movements of barred sand bass. To address this, project staff worked with California State University, Long Beach professor Dr. Chris Lowe and his master’s student, Megan McKinzie. Project staff assisted with field research that uses state-of-the-art technology to actively track adult barred sand bass at Huntington Flats during the spawning season. Fish were surgically fitted with acoustic transmitters and then followed by boat using an underwater hydrophone. Several transmitters contained a depth sensor which emitted a signal that allowed the researcher to determine both the horizontal and vertical movements of the fish every two seconds. The results from this research allowed us to characterize fine-scale horizontal and vertical movement patterns of tagged barred sand bass during the spawning and non-spawning seasons and to quantify activity space size (area and volume), habitat use and preference, and diel patterns of activity. Movement patterns believed to be indicative of spawning and/or courtship were determined through the comparison of spawning and non-spawning season individuals.

(1) With the fish immersed in a saltwater anesthetic bath, the transmitter is inserted through a small incision in the lower abdominal cavity.(2) Two to three sutures are used to close the incision.(3) Prior to release, the fish is measured and fitted with an external dart tag for easy identification upon recapture.DFG photos by E. Jarvis

Spawning Habitat

For some other aggregate spawners, the timing and location of spawning aggregations are related to water temperature, lunar activity, and currents. However, depth and bottom habitat type are the only characteristics documented in historical descriptions of barred sand bass spawning aggregation sites. To understand whether barred sand bass spawning aggregation sites were unique, Fisheries Independent Assessment Project staff conducted field surveys in 2008 to describe the typical oceanographic (e.g., water temperature), seafloor

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habitat (e.g., type of substrate), and biological features (e.g., invertebrates living on and in the substrate) of areas where spawning aggregations occur and areas where spawning aggregations are absent.

Barred sand bass “resting” at spawning grounds. DFG 1961.

Reproductive parameters

Spawning frequency

Understanding the reproductive potential of barred sand bass depends not only on how long fish stay at a spawning aggregation but how frequently they spawn. We can tell if a female has recently spawned if there are postovulatory follicles present in the ovaries, and if we know what proportion of females have postovulatory follicles, we can estimate spawning frequency. In a previous study, female barred sand bass were shown to spawn about every day and a half, but most samples were collected toward the tail end of peak spawning season and so frequency intervals may have been underestimated. To re-examine spawning frequency, 248 barred sand bass were collected from the Huntington Flats spawning grounds over the course of the spawning season (June-August 2011), gonads were removed and histologically sectioned and stained to visualize the internal gonadal structures and to identify postovulatory follicles.

Histological section from ovary of a barred sand bass collected at the Huntington Flats spawning aggregation. Several stages of oocyte development are present. Postovulatory follicle is labelled.

Spawning periodicity

Spawning is triggered in many species by environmental cues. In marine environments, common proximate cues include lunar and/or tidal flux. These cues are important for species to achieve synchrony in mating and

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may act as environmental indicators of optimal conditions for the survivorship of fertilized eggs or larvae. Barred sand bass may experience secondary environmental cues such as increased daylength or increased temperature that drive them to form spawning aggregations, but there may be proximate environmental cues throughout the spawning season that trigger spawning pulses. Understanding which cues trigger spawning in barred sand bass is important for understanding variability in annual reproductive potential. Reproductive hormones fluctuate with respect to environmental cues and may peak during spawning pulses. By analyzing hormone concentrations in barred sand bass over the course of the breeding season, we may determine if there is a relationship with lunar cycles and/or tidal flux. To determine the relationship between environmental cues and spawning, blood plasma was collected from 264 barred sand bass over the course of the 2011 spawning season at the Huntington Flats spawning grounds to test for concentrations of estradiol, progesterone and 11-ketotestosteron. In addition we will also describe how hormone concentrations relate to fish size, gonad size and the presence/absence of post-ovulatory follicles produced by females following spawning events.

Batch fecundity

Barred sand bass are serial spawners, meaning they may spawn many times over the course of a spawning season. As in other serial spawners, barred sand bass ovaries contain eggs at several different stages of development; however, only the hydrated eggs will be spawned. Batch fecundity refers to the number of eggs released in one spawning event. By determining the batch fecundity for several individuals over a wide size range, we can develop a batch fecundity-size relationship which will allow us to estimate the batch fecundity of females measured in the field. Batch fecundity will be an important parameter for estimating reproductive potential of barred sand bass. We collected gonads from 248 barred sand bass at the Huntington Flats spawning grounds over the course of the 2011 spawning season. To determine batch fecundity for an individual, we will count the number of hydrated eggs in the ovaries.

Age Structure and Validation

The age of most finfish can be determined by analysis of their otoliths. Otoliths are hard structures located in the inner ear that grow as the fish grows by accreting calcium carbonate. The rate of accretion is affected by seasonal changes in growth rate such that calcium carbonate rings may form annually and can be counted similar to tree rings. We collected otoliths from 352 barred sand bass at Huntington Flats in 2011. By counting the rings on the otoliths we can estimate the age structure of barred sand bass at the Huntington Flats spawning aggregation in 2011. While this is a common ageing technique in fish, no one has ever validated that the ring pattern is annual across size classes in barred sand bass. To examine this, we will keep barred sand bass of several size classes in captivity for at least one year. Shortly upon capture we will inject a chemical marker called oxytetracyline (OTC) into the musculature that is naturally incorporated into the otoliths. After a year, we will remove the otoliths and confirm the periodicity of the ring pattern.

Findings to Date

"Hotspot" Analysis

Five "hotspots" for barred sand bass catch were identified during the summer months, which are likely major spawning grounds for this species. The proportion of catch varied among these "hotspots" from 2004 to 2008 with Huntington Flats off Orange County and Imperial Beach ("I.B." Flats) on the U.S./Mexico border in San Diego County being the top catch locations. On a finer scale, natural reefs (Horseshoe Kelp and Palos Verdes Peninsula) and artificial structures (reefs, oil rigs, and breakwaters) were more important catch locations in the Huntington Beach Flats area outside of peak spawning season. This suggests that areas with higher relief or structure may serve as important habitat for barred sand bass before and after spawning activities.

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Map of the Southern California Bight showing the number of barred sand bass kept and released by private/rental boats from 2004-2008 by 1x1 mile fishing block from June - August. The percentages represent

the proportion of barred sand bass caught by county and standardized by area (1x1 mile fishing block).

Spawning movements

Tag and recapture data

The DFG received 972 barred sand bass tag returns from tagging efforts conducted in the 1960s and 1990s (an 11 percent recapture rate). Based on recapture frequencies, it appears that barred sand bass individuals remain on spawning grounds (e.g., Huntington Beach Flats) for at least one month during peak spawning season. Spawning residency at Huntington Flats was estimated by the frequency of returns over time; most same-year returns (82%, n = 141) were recaptured within a 35-d period, with secondary peaks in returns at 28 and 56 days at liberty.

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Frequency of tag returns over time for fish tagged during peak spawning season (Jun-Aug) at Huntington Flats and recaptured there within the same year.

Following spawning season, some fish remain, while others move away. The average migration distance from spawning locations was about 15 miles, although it appears that not all individuals at spawning grounds migrate to the same locations after spawning season. Overall, the farthest recapture distance was approximately 57 miles. Annual patterns in the timing and occurrence of recaptures strongly suggest barred sand bass visit the same spawning grounds year after year.

Recapture matrix of barred sand bass tagged during peak spawning season (Jun-Aug) and recaptured in subsequent peak spawning seasons.

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Fine-scale movements

Three distinct patterns of behavior were identified and believed to be representative of non-spawning season behavior, spawning season resting behavior, and spawning/courtship related behavior. Non-spawning season fish remained more closely associated with reef habitats than sand habitat, used smaller activity spaces, and remained more closely associated with the substratum than fish tracked during the spawning season.

Fish tracked during the spawning season used significantly more area and volume, and preferred sand over available reef habitats than fish tracked during non-spawning season. Spawning season fish typically utilized more of the available water column; individuals made dives toward the seafloor throughout the day and remained close to the seafloor at night. During the day, they remained primarily within or just below the thermocline (~ 16 °C), but continually made directed dives towards the seafloor lasting 15-30 sec; a behavior believed to be analogous to vertical spawning rushes demonstrated by other serranids. Fish tracked during spawning season also demonstrated movement patterns similar to non-spawning season fish and was believed to be resting behavior.

Box and whisker plots of day verses night activity space area during spawning and non-spawning seasons.

Box and whisker plots showing distance from bottom during day and night periods for both spawning and non-spawning fish.

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3-D graphical representation of barred sand bass activity space usage during: (a) the non-spawning season, (b) presumed spawning/courting behavior and (c) resting periods.

Spawning Habitat

Seafloor habitat and invertebrate densities

Not surprising, our results indicated the Huntington Flats largely consists of a uniform, sandy substrate; however, our analysis of existing substrate maps also identified several previously unknown areas of hard substrate sparsely scattered in the study area. Exploratory SCUBA dives conducted by Department staff identified barred sand bass on these reefs (some natural, some artificial) during peak spawning season, but we never observed courtship or spawning behavior even though dives occurred during daylight hours when barred sand bass are reported to spawn. Although there is potential barred sand bass spawn over reefs, the reefs may actually serve as areas for reproductive staging, resting, refuge, and foraging during spawning season.

The distribution of observed CPFV activity on barred sand bass spawning aggregations did not appear related to the distribution and (or) relative abundances of megabenthic invertebrates and benthic infauna. Fishermen have long associated barred sand bass spawning aggregations with “clam beds”; however video sea floor footage taken during opportunistic events on the Flats did not reveal evidence of large clam beds in the area. Although we did not collect sand bass stomachs for stomach content analysis, barred sand have been shown to shift their diet to predominantly epibenthic fishes and crabs as they become adults. Therfore, although clams occurred frequently in our benthic survey of the Flats, barred sand bass probably form aggregations over sand flats for reasons other than the presence of clams or other soft bottom prey items.

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Hard and soft substrate mapped within the Huntington Flats study area in southern California in 2008. Data source: California Seafloor Mapping Project. Some areas beyond state waters (3 nm) were not available. Circled numbers reference small patches of hard substrate within the study area. AR=artificial reef.

Oceanographic conditions at Huntington Flats

The development of a strong thermocline occurred during late July and early August and coincided with the highest, sustained catch of barred sand bass during peak spawning season. Thermocline temperatures measured within areas of presumed aggregation activity were significantly warmer than the average thermocline temperatures measured throughout the area during June, July, and August. In subsequent years, barred sand bass tracked during spawning season were associated with the thermocline during the daytime (see Fine-scale Movements above). Previous research on the optimal thermal habitat for barred sand bass egg and larval development suggests warmer thermocline temperatures may increase larval fitness.

Comparison of average thermocline temperatures on the Huntington Flats in June, July, and August, and during sampling events located within barred sand bass aggregation fishing activity, 2008. Error bars represent 95% confidence intervals, the asterisk denotes a statistical difference among means.

Daily catches of barred sand bass by the commercial passenger fishing vessel (CPFV) fleet were positively associated with fishing effort and tidal flux, and negatively associated with chlorophyll-a concentrations. These factors explained 72% of the variability in barred sand bass catch over the peak spawning season. Periods of high tidal flux occurred during both new and full moon phases; thus, the observed peaks in barred sand bass catch may represent a reproductive behavioral response to tidal amplitudes more so than moon phase. Sea surface currents were generally low during peak barred sand bass catches; however, Huntington Flats experienced large tidal fluxes of several feet.

The negative relationship between barred sand bass CPFV catches and chlorophyll-a concentrations is less clear. Chlorophyll-a concentrations are typically used as a proxy for phytoplankton abundance and tend to be inversely related to light transmissitivity in this area. A negative relationship with chlorophyll-a may reflect a preference of barred sand bass aggregations for increased water clarity, or it may reflect avoidance of planktivous forage fishes and zooplankton egg predators.

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Barred sand bass CPFV CPUE in the greater Huntington Flats area (CDFG fishing blocks 738 and 739), Balboa Pier oceanographic measurements (sea surface temperature, tidal flux, chlorophyll a concentration), and new and full moon periods during peak spawning season, 2008.

Reproductive Parameters

Spawning frequency

We are currently analyzing histology slides. Stay tuned!

Spawning periodicity

We are currently analyzing hormone data. Stay tuned!

Batch Fecundity

We are currently analyzing fecundity data. Stay tuned!

Age Structure and Validation

We are currently processing otoliths. Stay tuned!

Scientific Presentations and PublicationsUpdated June 7, 2012

Presentations

Posters

Gliniak, H.L., C.F. Valle, E.T. Jarvis, O. Horning, C. Linardich. (October 2010). Temporal trends in southern California surf fish populations 2007 to 2009. Mtg. American Institute of Fishery Research Biologists meeting, SCRIPPS Institution of Oceanography, La Jolla, CA.

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Jarvis, E.T., C. Linardich, C.F. Valle. (October 2010). Spawning-related movements of barred sand bass, Paralabrax nebulifer, in southern California: interpretations from two decades of historical tag and recapture data. Mtg. American Institute of Fishery Research Biologists, La Jolla, CA.

Gliniak, H.L., C. Valle, E.T. Jarvis, O. Horning, C. Linardich. (May 2009). Temporal trends in southern California surf fish populations. Ann. Mtg. Southern California Academy of Sciences, Palos Verdes, CA.

Horning, O., E.T. Jarvis, C.F. Valle. (May 2009). Spatial and temporal analysis of barred sand bass catch in the southern California private/rental boat fishery (2004-2008). Ann. Mtg. Southern California Academy of Sciences, Palos Verdes, CA.

Haas, D.L., S.M. Hoobler. (April 2009). Trapping and mark-recapture of nearshore fishes in Carmel Bay. Ann. Mtg. Monterey Bay National Marine Sanctuary Currents Symposium, Monterey, CA.

Lucas, S., C.F. Valle (April 2009). Mark and recapture studies of nearshore groundfishes at Carmel Pinnacles State Marine Reserve. Ann. Mtg. Monterey Bay National Marine Sanctuary Currents Symposium, Monterey, CA.

Linardich, C., E.T. Jarvis, C.F. Valle, P. Young. (May 2008). Using historical tagging data (1962-1971) to analyze the spawning related movements of barred sand bass, Paralabrax nebulifer (Serranidae) in southern California. Ann. Mtg. Southern California Academy of Sciences, Carson, CA.

Osorio, D.A., M. Bergen. (2006). Informing nearshore fishery management and monitoring California's

MPAs. American Academy of Underwater Sciences Diving for Science Symposium, Friday Harbor, WA.

Oral Presentations

Jarvis E.T., H.L. Gliniak, C.F.Valle. (2012). Fishery analysis on the basses in southern California. Marine Resources Committee Meeting, Santa Barbara, CA.

Haas, D.L. (2009). Status of the fisheries: Skates and rays. Ann. Conf. California Cooperative Oceanic Fisheries Investigations, Pacific Grove, CA.

Jarvis, E.T., C. Linardich, C.F. Valle. (2009). Spawning-related movements of barred sand bass, Paralabrax nebulifer, in southern California: interpretations from two decades of historical tag and recapture data. Ann. Mtg. Southern California Academy of Sciences, Palos Verdes, CA.

Jarvis, E.T., C.G. Lowe. (2008). Angling-induced barotrauma and two-day post-recompression survival in southern California rockfishes. 15th Western Groundfish Conference, Santa Cruz, CA.

Jarvis, E.T., C.G. Lowe. (2008). Bloating and floating don’t have to spell death: studying barotrauma in rockfishes. Sitka Conservation Society Backwoods and Waters Seminar Series, Sitka, AK. Co-sponsored by the Alaska Conservation Foundation, the Sitka Conservation Society, and the Sitka Marine Stewardship Roundtable.

Taniguchi, I., D.A. Osorio, D. Stein. (2007). Cooperative dive assessment of the red abalone resource at San Miguel Island, CA. American Academy of Underwater Sciences Diving for Science Symposium, Miami, FL.

Publications

Lowe, C.G., M.E. Blasius, E.T. Jarvis, T.J. Mason, G.D. Goodmanlowe, J.B. O’Sullivan. (2012). Historic fishery interactions with white sharks in the Southern California Bight. In: Domeier, M.L. (ed.) Global perspectives on the biology and life history of the white shark (pp. 169-198). Florida: Taylor and Francis Group, LLC.

Williams, J. P., J. T. Claisse, D. J. Pondella II, L. Medeiros, C. F. Valle and M. A. Shane. 2012. Patterns of Life History and Habitat Use of an Important Recreational Fishery Species, Spotfin Croaker, and Their Potential Fishery Implications, Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science, 4:1, 71-84. http://www.tandfonline.com/doi/abs/10.1080/19425120.2012.661392

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Haas, D.L. (2010). Skates and rays. In: Larinto, T. (ed.). Status of the Fisheries Report – An Update Through 2008. CA Dept. of Fish and Game [portable document file] p. 1-17.

Jarvis, E.T., C. Linardich, C.F. Valle. (2010). Spawning-related movements of barred sand bass, Paralabrax nebulifer, in southern California: Interpretations from two decades of historical tag and recapture data. Southern California Academy of Sciences Bulletin, 109:123-143.

Karpov, K.K., M. Bergen, J.J. Geibel, P.M. Law, C.F. Valle, D. Fox. (2010). Prospective (a priori) power analysis for detecting changes in density when sampling with strip transects. California Fish and Game 96:

Haas, D.L. (2009). Skates and rays. In: Sweetnam, D. (ed.). Review of selected California fisheries for 2008: Coastal Pelagic Finfish, Market Squid, Ocean Salmon, Groundfish, California Spiny Lobster, Spot Prawn, White Seabass, Kelp Bass, Thresher Shark, Skates and Rays, Kellet’s Whelk, and Sea Cucumber. CalCOFI Reports 50, p. 36-39.

Jarvis, E.T., H.L. Gliniak, O. Horning, C. Linardich. (2009). The occurrence of juvenile Mexican lookdown, Selene brevoortii (Gill 1863), in Seal Beach, California. California Fish and Game, 95:188-192.

Lowe, C.G., K.M. Anthony, E.T. Jarvis, L.F. Bellquist, M.S. Love. (2009). Site fidelity of characteristic fish species at offshore petroleum platforms in the Santa Barbara Channel. Marine and Coastal Fisheries, 1:71-89.

Jarvis, E.T., C.G. Lowe. 2008. The effects of barotrauma on the catch-and-release survival of southern California nearshore and shelf rockfishes (Scorpaenidae, Sebastes spp.). Canadian Journal of Fisheries and Aquatic Sciences, 65:1286–1296.

Pondella II, D.J., J.T. Froeschke, L.S. Wetmore, E. Miller, C.F. Valle, L. Medeiros. (2008). Demographic Parameters of Yellowfin Croaker, Umbrina Roncador (Perciformes: Sciaenidae), From the Southern California Bight. Pacific Science 62:555-568.

Jarvis, E., K. Schiff, L. Sabin, M.J. Allen. 2007. Chlorinated hydrocarbons in pelagic forage fishes and squid of the southern California Bight. Environmental Toxicology and Chemistry. 26:2290-2298.

Ugoretz, J., D.A. Osorio. (2006). "California Marine Life Protection Act and Marine Protected Areas." The Slate, Issue 3, American Academy of Underwater Sciences.

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