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Prior to burning down in 1906 CE, Point Alones in the Monterey Bay region of Central California was home to one of the largest Chinese fishing communities in the United States of America. Both historical records and the recovery of numerous cartilaginous fish (Chondrichthyes) vertebrae during archaeological excavations of the village indicate sharks were among the taxonomic groups being regularly harvested by its inhabitants. However, as shark vertebrae are difficult to identify past the family-level using conventional morphology-based approaches, our understanding of the Point Alones shark fishery remains incomplete. In this study, we address this issue by using ancient DNA analysis to assign species-level identifications to a sample of 54 shark vertebrae from the site. We successfully amplified a 173 bp fragment of the mitochondrial cytochrome c oxidase I gene from 47 of the 54 analyzed specimens (87.03%). Our results indicate that Tope Shark (Galeorhinus galeus; n = 39) was the primary focus of the site's shark fishery, with Brown Smooth-Hound (Mustelus henlei; n = 7) and Leopard Shark (Triakis semifasciata; n = 1) also harvested to a lesser extent. All three of these species are found locally in the waters overlying the continental shelf, suggesting Chinese fishers were harvesting sharks from these coastal environments. While some of the sharks caught by fishers from Point Alones were likely being consumed at the village, historical records suggest a significant number of fins from harvested Tope Sharks were also likely being exported to China and other diaspora communities. [ABSTRACT FROM AUTHOR]

Larval dispersal phases are a key determinant of population dynamics in recruitment-limited, coastal upwelling regions. Larvae were long considered to be highly susceptible to offshore transport, except in the lee of headlands where eddies form during upwelling conditions. We examined the spatial variation of benthic invertebrate larval assemblages in relation to the retentive upwelling shadow in northern Monterey Bay (California, USA) during strong upwelling (August 2013) and weak upwelling (October 2013). We characterized the spatial variation in physical characteristics of the water column, determined the cross-shore and depth distributions of invertebrate larvae in relation to the upwelling shadow, and examined how these physical and biological patterns change with upwelling strength. Larval abundances and environmental data (water temperature, salinity, chlorophyll a concentration) were collected simultaneously using a plankton pump and profiling CTD at 3 depths: above, within, and below the chlorophyll a maximum layer. Larvae were primarily detected near the bottom. Larvae of most taxa were positively associated with a subsurface chlorophyll a maximum layer in August, but not in October when this layer was near the surface. Adult habitat distribution was related to the spatial distribution of larvae. Larvae of nearshore taxa occurred in the inner bay, while larvae of predominately offshore taxa occurred in the outer bay. Taxa with similar adult habitat (nearshore versus offshore) co-occurred in water samples. In addition, larvae of offshore taxa were commonly associated with offshore water types. Thus, the distribution of larvae within northern Monterey Bay appears to be strongly influenced by adult habitat distribution, vertical positioning of larvae in the water column, and upwelling strength.

Larval dispersal phases are a key determinant of population dynamics in recruitment-limited, coastal upwelling regions. Larvae were long considered to be highly susceptible to offshore transport, except in the lee of headlands where eddies form during upwelling conditions. We examined the spatial variation of benthic invertebrate larval assemblages in relation to the retentive upwelling shadow in northern Monterey Bay (California, USA) during strong upwelling (August 2013) and weak upwelling (October 2013). We characterized the spatial variation in physical characteristics of the water column, determined the cross-shore and depth distributions of invertebrate larvae in relation to the upwelling shadow, and examined how these physical and biological patterns change with upwelling strength. Larval abundances and environmental data (water temperature, salinity, chlorophyll a concentration) were collected simultaneously using a plankton pump and profiling CTD at 3 depths: above, within, and below the chlorophyll a maximum layer. Larvae were primarily detected near the bottom. Larvae of most taxa were positively associated with a subsurface chlorophyll a maximum layer in August, but not in October when this layer was near the surface. Adult habitat distribution was related to the spatial distribution of larvae. Larvae of nearshore taxa occurred in the inner bay, while larvae of predominately offshore taxa occurred in the outer bay. Taxa with similar adult habitat (nearshore versus offshore) co-occurred in water samples. In addition, larvae of offshore taxa were commonly associated with offshore water types. Thus, the distribution of larvae within northern Monterey Bay appears to be strongly influenced by adult habitat distribution, vertical positioning of larvae in the water column, and upwelling strength.

Understanding sources of variability in larval supply and transport is integral to the dynamics, structure and effective management of marine populations and communities. Yet, a barrier to this understanding is the high variability in the supply and transport of marine larvae, especially in upwelling regions where wind forcing causes dynamic circulation. Since larvae of many species complete development close to shore, resolving the relationship between oceanographic processes and nearshore larval assemblages is essential to better understand larval transport in highly productive upwelling regions. The goal of our study was to examine the effects of variation in upwelling and relaxation dynamics on the nearshore larval assemblage in northern Monterey Bay. To determine how seasonal and daily upwelling and relaxation dynamics influence the nearshore larval assemblage, we surveyed distributions of marine larvae and physical, environmental factors along a cross-shelf transect in northern Monterey Bay, USA, during August and October of 2013. Conditions in August and October differed in temperature, salinity, stratification, and chlorophyll-a fluorescence. Richness and diversity of the larval assemblage did not change appreciably, but the abundance and composition of species shifted after the influx of offshore waters. Specifically, nearshore taxa were more abundant during August, which was characterized by strong upwelling conditions, and especially more abundant with increased wind forcing leading to a retentive upwelling shadow in the northern bay. Conversely, offshore taxa were more abundant during October, which was characterized by weakened upwelling and the persistent influx of offshore water. Our study suggests that relationships between larval taxa, life history characteristics, and water types provide insights into water mass history, circulation and larval recruitment in highly dynamic upwelling regions.

Understanding sources of variability in larval supply and transport is integral to the dynamics, structure and effective management of marine populations and communities. Yet, a barrier to this understanding is the high variability in the supply and transport of marine larvae, especially in upwelling regions where wind forcing causes dynamic circulation. Since larvae of many species complete development close to shore, resolving the relationship between oceanographic processes and nearshore larval assemblages is essential to better understand larval transport in highly productive upwelling regions. The goal of our study was to examine the effects of variation in upwelling and relaxation dynamics on the nearshore larval assemblage in northern Monterey Bay. To determine how seasonal and daily upwelling and relaxation dynamics influence the nearshore larval assemblage, we surveyed distributions of marine larvae and physical, environmental factors along a cross-shelf transect in northern Monterey Bay, USA, during August and October of 2013. Conditions in August and October differed in temperature, salinity, stratification, and chlorophyll-a fluorescence. Richness and diversity of the larval assemblage did not change appreciably, but the abundance and composition of species shifted after the influx of offshore waters. Specifically, nearshore taxa were more abundant during August, which was characterized by strong upwelling conditions, and especially more abundant with increased wind forcing leading to a retentive upwelling shadow in the northern bay. Conversely, offshore taxa were more abundant during October, which was characterized by weakened upwelling and the persistent influx of offshore water. Our study suggests that relationships between larval taxa, life history characteristics, and water types provide insights into water mass history, circulation and larval recruitment in highly dynamic upwelling regions.

Diarrhetic shellfish toxins (DSTs) are produced by the marine dinoflagellate, Dinophysis, as well as select species of benthic Prorocentrum. The DSTs can bioaccumulate in shellfish and cause gastrointestinal illness when humans consume high levels of this toxin. Although not routinely monitored throughout the U.S., recent studies in Washington, Texas, and New York suggest DSTs may be widespread throughout U.S. coastal waters. This study describes a four-year time series (2013-2016) of Dinophysis concentration and DST level in California mussels (Mytilus californianus) from Santa Cruz Municipal Wharf (SCMW) in Monterey Bay, California. Results show a maximum Dinophysis concentration of 9404 cells/L during this study and suggest Dinophysis persists as a member of the background phytoplankton community throughout the year. In California mussels, DSTs were found at persistent low levels throughout the course of this study, and exceeded the FDA guidance level of 160 ng/g 19 out of 192 weeks sampled. Concentrations of Dinophysis alone are a positive but weak predictor of DST level in California mussels, and basic environmental variables (temperature, salinity, and nutrients) do not sufficiently explain variation in Dinophysis concentration at SCMW. This study demonstrates that Dinophysis in Monterey Bay are producing DSTs that accumulate in local shellfish throughout the year, occasionally reaching levels of concern.

Our perception of deep-sea communities has evolved as various sampling approaches have captured different components of deep-sea habitats. We sampled midwater zooplankton assemblages in Monterey Bay, California to quantify community composition (abundance and biomass) and biodiversity (at the Order level) across three depth ranges, and the effects of sampling methodology on community parameters. We collected zooplankton using two types of opening-closing trawls [Tucker Trawl and Multiple Opening/Closing Net and Environmental Sensing System (MOCNESS)] and video recordings from a remotely operated vehicle (ROV). We quantified the relative contributions of microbes to community biomass using synoptic water-bottle casts and flow cytometry. Overall, the pelagic community was most similar between the Tucker trawl and ROV (dissimilarity = 52.4%) and least similar between the MOCNESS and ROV (dissimilarity = 65.8%). Dissimilarity between sampling methods was driven by the relative abundances of crustaceans and gelatinous taxa, where gelatinous animals (cnidarians, ctenophores, tunicates) were more abundant in ROV surveys (64.2%) and Tucker trawls (46.8%) compared to MOCNESS samples (14.5%). ROV surveys were the only method that sufficiently documented the most physically delicate taxa (e.g., physonect siphonophores, lobate ctenophores, and larvaceans). Biomass was also one order of magnitude lower in MOCNESS trawls compared to Tucker trawls. Due to these large differences, the relative contributions of microbes to total biomass were substantially lower in Tucker trawl samples (mean = 7.5%) compared to MOCNESS samples (mean = 51%). These results illustrate that our view of planktonic composition and community biomass is strongly dependent on sampling methodology.

Common ravens (Corvus corax; ravens) are known nest predators that have the ability to negatively impact nesting birds, including imperiled species of seabirds and shorebirds. We conducted systematic necropsies of ravens that were lethally controlled in Monterey Bay, California, USA during 2013-2015, in or near western snowy plover (Charadrius nivosus nivosus) nesting areas, in an effort to better understand body condition, overall health, and diet of individual ravens. Raven predation of snowy plover nests has increased over the years in the Monterey Bay study area, and lethal removal of ravens has been employed to reduce predation. Most ravens examined in this study were in moderate to excellent body condition and also exhibited good organ health. There were statistically significant differences between male and female morphometrics (mass, culmen length, and wing length; P < 0.05). Stomach content analysis indicated a varied diet with consumption of animal remains and eggshell fragments, and anthropogenic sources of food (e.g., human food items and human-produced nonfood items). Our study provides evidence that lethal control of ravens targeted some individual ravens that were responsible for depredating snowy plover nests. [ABSTRACT FROM AUTHOR]

Pleasure Reading [ABSTRACT FROM AUTHOR]

As a demonstrator for technologies for the next generation of ocean color sensors, the Hyperspectral Imager for the Coastal Ocean (HICO) provides enhanced spatial and spectral resolution that is required to understand optically complex aquatic environments. In this study we apply HICO, along with satellite remote sensing and in situ observations, to studies of phytoplankton ecology in a dynamic coastal upwelling environment-Monterey Bay, CA, USA. From a spring 2011 study, we examine HICO-detected spatial patterns in phytoplankton optical properties along an environmental gradient defined by upwelling flow patterns and along a temporal gradient of upwelling intensification. From a fall 2011 study, we use HICO's enhanced spatial and spectral resolution to distinguish a small-scale "red tide" bloom, and we examine bloom expansion and its supporting processes using other remote sensing and in situ data. From a spectacular HICO image of the Monterey Bay region acquired during fall of 2012, we present a suite of algorithm results for characterization of phytoplankton, and we examine the strengths, limitations, and distinctions of each algorithm in the context of the enhanced spatial and spectral resolution. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

The Vibrionaceae (Vibrio) are a ubiquitous group of metabolically flexible marine bacteria that play important roles in biogeochemical cycling in the ocean. Despite this versatility, little is known about Vibrio diversity and abundances in upwelling regions. The seasonal dynamics of Vibrio populations was examined by analysis of 16S rRNA genes in Monterey Bay (MB), California from April 2006-April 2008 at two long term monitoring stations, C1 and M2. Vibrio phylotypes within MB were diverse, with subpopulations clustering with several different cultured representatives including Allivibrio spp., Vibrio penaecida, and Vibrio splendidus as well as with many unidentified marine environmental bacterial 16S rRNA gene sequences. Total Vibrio population abundances, as well as abundances of a Vibrio sp. subpopulation (MBAY Vib7) and an Allivibrio sp. subpopulation (MBAY Vib4) were examined in the context of environmental parameters from mooring station and CTD cast data. Total Vibrio populations showed some seasonal variability but greater variability was observed within the two subpopulations. MBAY Vib4 was negatively associated with MB upwelling indices and positively correlated with oceanic season conditions, when upwelling winds relax and warmer surface waters are present in MB. MBAY Vib7 was also negatively associated with upwelling indices and represented a deeper Vibrio sp. population. Correlation patterns suggest that larger oceanographic conditions affect the dynamics of the populations in MB, rather than specific environmental factors. This study is the first to target and describe the diversity and dynamics of these natural populations in MB and demonstrates that these populations shift seasonally within the region.

Recent work using compound-specific stable isotopes of amino acids (CSI-AA) in proteinaceous deep-sea corals opens a new realm of high-fidelity reconstruction for biogeochemical and ecological changes in the ocean. However, underlying these CSI-AA paleoceanographic applications are a series of fundamental assumptions, which hold first that baseline-proxy AA isotope values fixed at the base of food webs represent integrated δ13C and δ15N values of primary production, and second they are unaltered during subsequent export and incorporation from particles into corals. We explored long-term δ13C and δ15N CSI-AA data on a sediment trap time series together with contemporaneous, geographically close deep-sea bamboo corals (Isidella sp.) in the California margin, directly testing these assumptions for the first time. Our data show that isotope values of essential (δ13C EAA) and source AAs (δ15N Phe) in sinking particles quantitatively track bulk δ13C and δ15N values of export production. These CSI-AA baseline proxies varied independently of carbon flux, trophic position (TP CSI-AA) and microbial alteration, suggesting that they were well preserved in the sinking particles consumed by corals. Paired comparisons between sinking particles and corals revealed minor elevations of δ13C EAA (by ∼2‰) and δ15N Phe (by ∼1‰) in available coral specimens. We hypothesize that the difference in δ13C EAA is due to the geographic offset in δ13C values of primary production expected between the (more offshore) sediment trap site and (more onshore) coral specimens, whereas the δ15N Phe offset is likely related to expected minor trophic fractionation. Using empirical models derived from the sediment trap time series, we demonstrate for the first time that CSI-AA in proteinaceous deep-sea corals can reconstruct known bulk δ15N values of export production, source nitrogen δ15N values, and exported TP CSI-AA values with very good fidelity. Together, these findings represent a major advance in our understanding of AA isotope behavior in modern and paleoarchives, and can be used to underpin the rapidly evolving use of CSI-AA-based tools in multiple paleoceanographic studies and archives. [ABSTRACT FROM AUTHOR]

Exercise Is Medicine® On Campus (EIM-OC) is a worldwide initiative from the American College of Sports Medicine (ACSM) to promote physical activity (PA) at universities. California State University, Monterey Bay (CSUMB) implemented this initiative in Fall 2019 with offerings to students and employees. For employees, an "Introduction to Resistance Training Class" was offered. Participants attended classes two times per week, with the sessions lasting approximately fifty minutes. The purpose of this study was to evaluate the EIM-OC employee Introduction to Resistance Training class for its effectiveness on increasing PA, self-efficacy, and outcome expectancy. The research design was pre-post, with participants completing online questionnaires before and after the course. The Godin Leisure Time Physical Activity Questionnaire (LTPQ), Resistance Training Self-Efficacy and Outcome Expectancy Questionnaire, and Self-Efficacy and the Maintenance of Exercise Participation in Older Adults Questionnaire were included. The training class had a total of 14 female participants, 12 of which completed the pre- and postquestionnaires. There was a significant increase (t=-3.2, df=11, p=.004) in resistance training self-efficacy score following the course (M=3.52±1.03 versus M=4.31±.56). Resistance training outcome expectancy score was also statistically significant (t=- 2.54, df=11, p=.01) following the course (M=4.48±.53 versus M=4.71±.37). There were increases in strenuous exercise days, physical activity scores, and future resistance training self-efficacy, although they were not statistically significant. The results of this study indicate that employee exercise classes, as part of the EIM-OC initiative, can be effective in increasing resistance training self-efficacy, and outcome expectancy. These indicators are important for individuals to maintain lifelong PA therefore future programming and research on EIM-OC should continue. [ABSTRACT FROM AUTHOR]

Geodetic observations in the oceans are important for understanding plate tectonics, earthquake cycles and volcanic processes. One approach to seafloor geodesy is the use of seafloor pressure gauges to sense vertical changes in the elevation of the seafloor after correcting for variations in the weight of the overlying oceans and atmosphere. A challenge of using pressure gauges is the tendency for the sensors to drift. The A-0-A method is a new approach for correcting drift. A valve is used to periodically switch, for a short time, the measured pressure from the external ocean to the inside of the instrument housing at atmospheric pressure. The internal pressure reading is compared to an accurate barometer to measure the drift which is assumed to be the same at low and high pressures. We describe a 30-months test of the A-0-A method at 900 m depth on the MARS cabled observatory in Monterey Bay using an instrument that includes two A-0-A calibrated pressure gauges and a three-component accelerometer. Prior to the calibrations, the two pressure sensors drift by 6 and 2 hPa, respectively. After the calibrations, the offsets of the corrected pressure sensors are consistent with each other to within 0.2 hPa. The drift corrected detided external pressure measurements show a 0.5 hPa/yr trend of increasing pressures during the experiment. The measurements are corrected for instrument subsidence based on the changes in tilt measured by the accelerometer, but the trend may include a component of subsidence that did not affect tilt. However, the observed trend of increasing pressure, closely matches that calculated from satellite altimetry and repeat conductivity, temperature and depth casts at a nearby location, and increasing pressures are consistent with the trend expected for the El Niño Southern Oscillation. We infer that the A-0-A drift corrections are accurate to better than one part in 105 per year. Additional long-term tests and comparisons with oceanographic observations and other methods for drift correction will be required to understand if the accuracy the A-0-A drift corrections matches the observed one part in 106 per year consistency between the two pressure sensors.

Phytoplankton samples were collected off the Monterey Municipal Wharf II at a single location (36º 36’ N and 121º 53’ W) weekly from June 2003 to March 2010. The contribution of five algal groups to total chlorophyll a (chl a) was derived using CHEMTAX from biomarker pigment measurements made via HPLC analysis. The purpose of this study was to specifically define the relative abundances of diatoms and dinoflagellates on a seasonal and interannual basis. Spearman’s rho (ρ) correlation coefficients were calculated to determine the strength of the relationship between the diatoms and dinoflagellates and two environmental variables; sea surface temperature (SST) and upwelling indices (UI). During the summer of 2004 and until the end of 2006, previous studies had suggested that the typical diatom-dominated bay shifted to a dinoflagellate-dominated system resulting from global warming effects on mixed layer stability. The high-resolution (weekly), long-term (2003-2010) sampling regime described in the current study coincided with this time frame and allowed a robust test of the tenet that “the age of dinoflagellates” had developed in Monterey Bay.Pigment analysis indicated that diatoms and dinoflagellates displayed interannual and seasonal variability, particularly during the anomalous oceanographic conditions from 2004-2006. Diatoms were most abundant during the upwelling season and displayed a significant and positive correlation to UI, while they exhibited no relationship with shifts in SST. The dinoflagellates revealed a consistent fall bloom each year, displayed a significantly positive correlation to increases in SST and a significantly negative correlation to UI. This data set proved to be a robust, unique collection that clearly captured the “age of dinoflagellates” and compared well with larger scale studies conducted off shore waters of Monterey Bay, indicating the value of high frequency shore station based monitoring for tracking major oceanographic features. In this study, however, it was shown that the dominant period of dinoflagellates was short-lived since diatoms returned to dominance in 2007.

Expanding the collection of Planctomycetes by characterisation of novel species is key to better understanding of their complex lifestyles, uncommon cell biology and unexplored metabolism. Here, we isolated three novel planctomycetal strains from a kelp forest on the California Coastline at Monterey Bay or from plastic surfaces submerged in the Baltic Sea and the estuary of the river Warnow in the northeast of Germany. According to our phylogenetic analysis, the isolated strains Poly21T, Pla100T and CA85T represent three novel species within the genus Rhodopirellula. All three show typical planctomycetal traits such as division by budding. All are aerobic, mesophilic chemoheterotrophs and show genomic features comparable to other described Rhodopirellula species. However, strain CA85T is exceptional as it forms cream colonies, but no aggregates, which is a notable deviation from the pink- to red-pigmented and aggregate-forming Rhodopirellula species known thus far. We propose the names Rhodopirellula heiligendammensis sp. nov., Rhodopirellula pilleata sp. nov., and Rhodopirellula solitaria sp. nov. for the novel strains Poly21T (DSM 102266T = LMG 29467T = CECT 9847T = VKM B-3435T), Pla100T (DSM 102937T = LMG 29465T) and CA85T (DSM 109595T = LMG 29699T = VKM B-3451T), respectively, which we present as the respective type strains of these novel species. [ABSTRACT FROM AUTHOR]

The main goal of this study was to gather information about historical changes in water temperature and species composition, in order to identify variables that will enable us to predict changes in water temperatures and species abundances in California caused by global climate change. Our primary objectives were to (1) review the existing published and unpublished data sets to refine our understanding of trends in sea surface temperature in central California; (2) review fish and climate data sets to determine if we could identify how species abundances changed relative to changes in water temperatures and basin-scale environmental indices; and (3) identify recent changes in species abundances in central California that are related to water temperatures.

Monterey Bay, CA is an Eastern boundary upwelling system that is nitrogen limited much of the year. In order to resolve population dynamics of microorganisms important for nutrient cycling in this region, we deployed the Environmental Sample Processor with quantitative PCR assays targeting both ribosomal RNA genes and functional genes for subclades of cyanobacteria (Synechococcus) and ammonia-oxidizing Archaea (Thaumarchaeota) populations. Results showed a strong correlation between Thaumarchaea abundances and nitrate during the spring upwelling but not the fall sampling period. In relatively stratified fall waters, the Thaumarchaeota community reached higher numbers than in the spring, and an unexpected positive correlation with chlorophyll concentration was observed. Further, we detected drops in Synechococcus abundance that occurred on short (that is, daily) time scales. Upwelling intensity and blooms of eukaryotic phytoplankton strongly influenced Synechococcus distributions in the spring and fall, revealing what appear to be the environmental limitations of Synechococcus populations in this region. Each of these findings has implications for Monterey Bay biogeochemistry. High-resolution sampling provides a better-resolved framework within which to observe changes in the plankton community. We conclude that controls on these ecosystems change on smaller scales than are routinely assessed, and that more predictable trends will be uncovered if they are evaluated within seasonal (monthly), rather than on annual or interannual scales.

This study explores the cycling of phosphorus (P) in the euphotic zone following upwelling in northeastern Monterey Bay (the Red Tide Incubator region) of coastal California, with particular emphasis on how bacteria and phytoplankton that form harmful algal blooms mediate and respond to changes in P availability. In situ measurements of nutrient concentrations, phytoplankton community composition, and cell-specific alkaline phosphatase (AP) activity (determined via enzyme-labeled fluorescence assay) were measured during three cruises. Upwelling led to a 10-fold increase in dissolved inorganic (DIP) in surface waters, reaching ∼0.5 μmol L−1. This DIP was drawn down rapidly as upwelling relaxed over a period of 1 week. Ratios of nitrate to DIP drawdown (∼5:1, calculated as the change in nitrate divided by the change in DIP) were lower than the Redfield ratio of 16:1, suggesting that luxury P uptake was occurring as phytoplankton bloomed. Dissolved organic (DOP) remained relatively constant (∼0.3 μmol L−1) before and immediately following upwelling, but doubled as upwelling relaxed, likely due to phytoplankton excretion and release during grazing. This transition from a relatively high DIP:DOP ratio to lower DIP:DOP ratio was accompanied by a decline in the abundance of diatoms, which had low AP activity, toward localized, spatially heterogeneous blooms of dinoflagellates in the genera Prorocentrum, Ceratium, Dinophysis, Alexandrium, andScrippsiella that showed high AP activity regardless of ambient DIP levels. A nutrient addition incubation experiment showed that phytoplankton growth was primarily limited by nitrate, followed by DIP and DOP, suggesting that P regulates phytoplankton physiology and competition, but is not a limiting nutrient in this region. AP activity was observed in bacteria associated with lysed cell debris and aggregates of particulate organic material, where it may serve to facilitate P regeneration, as well as affixed to the surfaces of intact phytoplankton cells, possibly indicative of close, beneficial phytoplankton–bacteria interactions.

Pseudo-nitzschia is a cosmopolitan marine diatom which can cause the poisoning of humans, marine mammals, and birds through the production of the neurotoxin domoic acid and subsequent contamination of the marine food web. Severe poisoning events are induced when environmental conditions allow: (1) the rapid proliferation ('bloom') of resident toxic species of Pseudo-nitzschia, and/or (2) their enhanced toxin production, and (3) the conveyance of the toxin into prey items. The introduction of domoic acid into the food web was recognized as a public health concern along the coast of California following a Pseudo-nitzschia bloom and seabird mortality event in the Monterey Bay area in 1991, and blooms of Pseudo-nitzschia have since been observed in the region with regularity. Since the recognition of the public health concern posed by these recurrent harmful algal bloom (HAB) events, the California Department of Public Health (CDPH) has been charged with protecting the public from domoic acid intoxication through the Preharvest Shellfish Protection and Marine Biotoxin Monitoring Program. This regulatory program (1) conducts, surveys, classifies and monitors commercial shellfish growing areas, and (2) monitors numerous points along the California coastline for marine biotoxins in shellfish and toxigenic phytoplankton in the waters. While these regulatory efforts have successfully prevented significant injury to public health since they began, they remain relatively inefficient in terms of time, energy, and cost.This thesis begins with an investigation of the environmental factors that contribute to Pseudo-nitzschia bloom formation in Monterey Bay (Chapter 1). The identification of nitrate and river discharge as seasonal bloom factors motivated an explicit evaluation and contextualization of river nitrate loading within the 'upwelling-dominated' region of Monterey Bay (Chapter 2). Finally, a new monitoring technology, Solid Phase Adsorption Toxin Tracking (SPATT), is presented, developed primarily for use by public health managers for more effective and efficient monitoring of domoic acid, the toxin produced by Pseudo-nitzschia and the ultimate cause for concern (Chapter 3, with addendum).

This project examines whether rocky intertidal nudibranchs (brightly colored shallow-water mollusks also known as sea slugs) can be used as fine-scale indicators of inter-annual and decadal-scale climate variability. As part of this research, biologists offer a partial explanation for an observed decline in sea slugs off Central California, and document the climate-induced range shift of one particularly aggressive predatory “killer” sea slug and its effect on intertidal ecology at Duxbury Reef in Marin County. Field studies have led to the discovery of two new species of sea slugs.

(1) The abundance, species richness, and community composition of nudibranchs in central California has changed significantly in the past 30 to 70 years.(2) The observed changes are consistent with those predicted by climate variability on interannual and decadal time scales. Specifically, during warm phases: (a) the proportional abundance and speciesrichness of southern species should increase, as northern species decline, and (b) geographic ranges should shift poleward. The reverse of these should occur during periods of cooling. Further, these changes should be apparent at multiple, widespread sites (otherwise, more localized environmentalfactors, and not broad scale climate factors, would be implicated as the cause).(3) Long-term, anthropogenic climate warming is superimposed on natural climate variation, and its biological signal (similar to that described above for natural periods of warming) should be apparent bycomparing the abundance, species richness, and community composition across (1) full cycles of natural decadal variation, preferably at multiple sites, and (2) across entire single phases of decadal variation.(4) While climate change may be the ultimate factor behind community changes we document, especially those related to shifts in geographic ranges, climatic impacts on ecologically important species could result in a cascade of indirect effects on other species. In 1977, the large aeolidnudibranch, Phidiana hiltoni, began spreading northward from Monterey, California. By 1992 it had reached Duxbury Reef, 100 km to the north, where other nudibranchs subsequently appeared todecline. We will also test the hypothesis that P. hiltoni attacks and consumes other species of nudibranchs and has caused these apparent declines.

Coastal upwelling regions are hotspots of biological productivity, supporting diverse communities of microbial life and metabolisms. Monterey Bay (MB), a coastal ocean embayment in central California, experiences seasonal upwelling of cold, nutrient-rich waters that sustain episodes of high phytoplankton production in surface waters. While productivity in surface waters is intimately linked to metabolisms of diverse communities of Archaea and Bacteria, a comprehensive understanding of the microbial community in MB is missing thus far, particularly in relation to the distinct hydrographic seasons characteristic of the MB system. Here we present the results of a 2-year microbial time-series survey in MB, investigating community composition and structure across spatiotemporal gradients. In deciphering these patterns, we used unique sequence variants (SVs) of the 16S rRNA gene (V4–V5 region), complemented with metagenomes and metatranscriptomes representing multiple depth profiles. We found clear depth-differentiation and recurring seasonal abundance patterns within planktonic communities, particularly when analyzed at finer taxonomic levels. Compositional changes were more pronounced in the upper 0–40 m of the water column, whereas deeper depths were characterized by temporally stable populations. In accordance with the dynamic nutrient profiles, the system appears to change from a Bacteroidetes- and Rhodobacterales-dominated upwelling period to an oceanic season dominated by oligotrophic groups such as SAR11 and picocyanobacteria. The cascade of environmental changes brought about by upwelling and relaxation events thus impacts microbial community structure in the bay, with important implications for the temporal variability of nutrient and energy fluxes within the MB ecosystem. Our observations emphasize the need for continued monitoring of planktonic microbial communities in order to predict and manage the behavior of this sensitive marine sanctuary ecosystem, over projected intensification of upwelling in the region.

Domoic acid (DA) is a neurotoxin that causes amnesic shellfish poisoning, and fish are recognized vectors of DA to marine fauna. However, the exposure of anglers through consumption of DAcontaminated fish is unknown. We measured DA in 11 fish species targeted by Santa Cruz Wharf (SCW) anglers in Monterey Bay, California, USA, and surveyed anglers regarding their fish consumption patterns. In addition, we used California mussel Mytilus californianus DA data provided by the state of California and our measurements of DA in seawater to examine the associations between DA in fish viscera versus in mussels and seawater. DA was detected in the viscera of 7 fish species commonly consumed by anglers, and toxin uptake in fishes varied according to their diet. DA was almost entirely in the viscera, with low DA concentrations detected in muscle tissue. The majority of anglers (58% of 565) reported consuming their catch, with a small fraction ingesting the viscera. Total DA concentrations in fish decreased significantly after 11 mo storage at –20°C. DA concentration in seawater and California mussels was correlated with DA in the viscera of some but not all fish groups. We conclude that SCW anglers who consume their catch are exposed to asymptomatic DA doses, and that exposure is a function of the species and parts consumed, as well as storage methods and DA levels in the seawater when the fish are caught.

First, using one method of change detection analysis called the cumulative sum, it is possible to detect and characterize regime shifts along the California coast using sea surface temperatures (SSTs) and other variables. Second, physically-determined regime shifts and changes in ocean climatology, determined largely through detailed temperature time-series, can be linked to corresponding changes in biological communities, particularly phytoplankton, which exhibit rapid generation times.

Coastal upwelling regions are hotspots of biological productivity, supporting diverse communities of microbial life and metabolisms. Monterey Bay (MB), a coastal ocean embayment in central California, experiences seasonal upwelling of cold, nutrient-rich waters that sustain episodes of high phytoplankton production in surface waters. While productivity in surface waters is intimately linked to metabolisms of diverse communities of Archaea and Bacteria, a comprehensive understanding of the microbial community in MB is missing thus far, particularly in relation to the distinct hydrographic seasons characteristic of the MB system. Here we present the results of a 2-year microbial time-series survey in MB, investigating community composition and structure across spatiotemporal gradients. In deciphering these patterns, we used unique sequence variants (SVs) of the 16S rRNA gene (V4–V5 region), complemented with metagenomes and metatranscriptomes representing multiple depth profiles. We found clear depth-differentiation and recurring seasonal abundance patterns within planktonic communities, particularly when analyzed at finer taxonomic levels. Compositional changes were more pronounced in the upper 0–40 m of the water column, whereas deeper depths were characterized by temporally stable populations. In accordance with the dynamic nutrient profiles, the system appears to change from a Bacteroidetes- and Rhodobacterales-dominated upwelling period to an oceanic season dominated by oligotrophic groups such as SAR11 and picocyanobacteria. The cascade of environmental changes brought about by upwelling and relaxation events thus impacts microbial community structure in the bay, with important implications for the temporal variability of nutrient and energy fluxes within the MB ecosystem. Our observations emphasize the need for continued monitoring of planktonic microbial communities in order to predict and manage the behavior of this sensitive marine sanctuary ecosystem, over projected intensification of upwelling in the region. [ABSTRACT FROM AUTHOR]

The extensive anthropogenic armoring of the shoreline in California changes the substrate available to settling invertebrate larvae and algal spores that are passively distributed in the ocean currents. Rock types available to settlers likely influences community structure in the intertidal, as rock characteristics have been shown to favor or inhibit settlement. Much research has been done examining the mechanisms that determine intertidal community patterns, but the role of rock type has been largely neglected. My goals are to: 1) determine the structure of community assemblages occurring on different rock types, 2) examine the mechanisms responsible for any differences, and 3) link the community structure patterns to life history characteristics of selected species. I have conducted two studies—the first comparing two sites with armored, rip-rapped shorelines (Chapter 2) and the second using settlement plates at two sites with different bedrock within Monterey Bay, California (Chapters 3 and 4). The intertidal community structure on the armored rocks and settling plates shows different patterns for certain species distributions that warrant further examination. These studies will help in predicting how continued armoring of the shoreline will affect species assemblages, as well as enhancing our understanding of variation in intertidal community assemblages at different sites along the coast.

I developed two conceptual models addressing fishery questions in the Monterey Bay motivated by 1) the California Market Squid (Loligo opalescens) and 2) marine reserves as a recovery and management tool. The model for California Market Squid incorporates the close ties between environmental variability and squid life history. Inclusion of environmental factors in the model provides a biological mechanism contributing to the large fluctuations that occur in the fishery. Furthermore, I predict that removal of 30% of the unspawned SSB may drive the population to extinction within 30 generations.Reserves are generally agreed to be good for habitat and ecosystem conservation; however, specific measures of success, such as increases in yield or size at age have been difficult to generalize across reserves. I identify density dependent body growth and displaced fishing effort as potential explanations for the variable outcomes. I predict that density dependent body growth will reduce length at age inside reserves, even if mean length in the reserve increases. I also predict that although reserves increase yield, nothing maximizes yield as well as conservative fishing practices, and that displaced fishing effort decreases benefits of reserves, indicating the need to reduce effort, as well as create reserves.

The goal of this project is to develop a set of protocols for monitoring marine organisms living in the rocky intertidal habitats of the Monterey Bay National Marine Sanctuary, an area that stretches from San Luis Obispo to San Francisco. What distinguishes this project, called the Seymour Intertidal Monitoring Program, from others is that it is being designed to be carried out by high school students—not just as a learning experience for their benefit but also as a real contribution to professional science.

Over the past decade the consumption of planktivorous northern anchovies containing the diatom-produced neurotoxin, domoic acid (DA), has been responsible for severe neurologic illness and mass mortality events involving hundreds of sea birds and marine mammals in Monterey Bay, California. This research characterizes the dynamics of DA transfer, accumulation, and neurotoxicity in this pivotal and dangerous DA vector fish species. Chapter one documents aDA-poisoning event in which dozens of California sea lions died as a result of consuming DA-contaminated anchovies in Monterey Bay. DA levels in sea lion feces and anchovies were attained using HPLC-UV and microplate receptor binding assays, with absolute confirmation by tandem mass spectrometry. The presence of toxic Pseudo-nitzschia frustules in sea lion feces and anchovy gut contents was determined using scanning electron microscopy. Chapter two presents data from an intracoelomic injection study in which anchovies were shown to be neurologically susceptible to DA excitotoxicity and to have a similar sensitivity to the toxin as mammals. Excitotoxic symptoms are described and conrum that DA crosses the blood brain barrier in fish.  Chapter three characterizes the dynamics of DA accumulation in small planktivorous fish in relation to ecologically relevant toxic diatom densities. Toxic Pseudo-nitzschia densities and DA levels in anchovies and sardines were measured from samples collected weekly throughout Monterey Bay from 10/8/99 to 10/8/00. DA levels in fish were estimated via HPLC-UV and toxic cell densities were determined via whole cell hybridization with species-specific large subunit rRNA-targeted fluorescent probes. DA levels accumulated in fish viscera tracked toxic cell densities in surface waters confirming that anchovies and sardines regularly consume toxic diatoms when present in Monterey Bay. Fish viscera DA levels harmful to piscivorous predators occurred when toxic cell densities exceeded 104 cells liter -1. Anchovies accumulated more DA than sardines in viscera, however neither species appears to accumulate significant levels of toxin in body tissue. Finally, Appendix A includes results from histologic examination of brain sections taken from control and DA-intoxicated anchovies and stained with haemotoxylin and eosin dyes. Although intoxicated fish exhibited seizures, brain lesions characteristic of DA excitotoxicity were not found.

The organic sulfur compound dimethylsulfoniopropionate (DMSP) is synthesized by numerous species of marine phytoplankton, and its volatile degradation products are a major source of biogenic sulfur to the atmosphere. A massive bloom of the dinoflagellate Akashiwo sanguinea occurred in Monterey Bay, CA, USA, in the fall of 2016 and led to exceptionally high seawater DMSP concentrations that peaked at 4,240 nM. Bacterial consumption rates showed that only a small fraction of the DMSP standing stock flowed through the dissolved DMSP pool per day, contributing to the high DMSP concentrations and creating conditions conducive to production of dimethylsulfide (DMS). Conservative calculations of DMS yield from this persistent A. sanguinea bloom suggest substantial regional‐scale inputs of DMS‐sulfur to the atmosphere. Other recently reported major coastal blooms of A. sanguinea, along with indications that this species may benefit from climate change conditions, reveal a mechanism that could alter oceanic contributions to atmospheric sulfur pools. Plain Language Summary: Marine phytoplankton produce the organic sulfur compound dimethylsulfoniopropionate (DMSP), which is used for osmotic balance and serves as a carbon and sulfur source to marine bacteria. A massive bloom of a dinoflagellate in Monterey Bay, CA, USA, in 2016 resulted in extremely high concentrations of DMSP over a 6‐week period, the highest DMSP concentrations yet recorded. This extended bloom established ideal conditions for the release of volatile sulfur from the ocean. More frequent and extensive blooms of DMSP‐producing phytoplankton have been observed and may affect ocean contributions to the atmospheric sulfur pool and the formation of cloud condensation nuclei. Key Points: A dinoflagellate bloom of exceptional proportions occurred in Monterey Bay and offshore regions of the Pacific Ocean in fall 2016DMSP concentrations during 46 days of the Akashiwo sanguinea bloom were the highest ever recordedOnly a small fraction of the DMSP standing stock flowed through the dissolved pool each day, creating conditions conducive to high DMS flux [ABSTRACT FROM AUTHOR]

Natural resource sustainability depends on adaptive capacity: the latent ability of a social-ecological system to rely on or implement effective strategies to cope with disturbances. We propose and implement a new three-step framework for studying a social-ecological system's adaptive capacity that consists of assessment, strategy identification, and activation. We apply this framework to analyze the adaptive capacity of the Monterey Bay wetfish fisheries community in response to a significant stressor in the system: El Niño Southern Oscillation (ENSO). We conducted 49 semi-structured interviews with participants engaged in these fisheries and/or providing ENSO information. Of the 67 social-ecological strategies identified through a literature review, we found 42 contribute to high adaptive capacity to ENSO. The most influential strategies were matching formal and informal rules to system dynamics, diversifying livelihoods, enhancing economic safety nets, social learning, and accessing early warning systems. Our findings suggest approaches for enhancing adaptive capacity in other resource systems. [ABSTRACT FROM AUTHOR]

Over the open ocean, the aerodynamic drag coefficient is typically well predicted; however, the impact depth‐limited processes have on the drag remains underexplored. A case study is presented here where winds, waves, and currents were simultaneously observed from a mobile platform that repeatedly transected the inner shelf of Monterey Bay, CA. Eddy covariance‐derived drag coefficients were compared to several bulk parameterizations, including all of the roughness variations of COARE 3.5 and two explicitly depth‐limited models. The analysis demonstrated that the drag was underestimated by O(2–4) times and the variability with wind speed or cross‐shore distance was not well predicted. The drag based on a recent depth‐limited roughness length model performed substantially better than the rest of the bulk estimates, which were all within 15% of each other and effectively equivalent given typical operational uncertainties. The measured friction velocity was compared to a wave‐dependent parameterization and generalizing the model to arbitrary water depth significantly improved the mean observation‐model difference to within 30%. Latent variability in the observation‐model comparison was associated with stability, wind direction, and wave steepness. The wind stress angle variability was also analyzed. Stress veering was correlated with the alongshore surface current within 2 km from shore (r2= 0.7–0.95, p < 0.05); offshore of this margin, consistent wind stress veering was observed and may be attributable to a secondary, low‐frequency swell system. These results demonstrate that it remains a persistent challenge to accurately predict wind stress variability in the nearshore, especially at locations with complex wave and current fields. Plain Language Summary: As the wind blows over the ocean surface, the atmosphere experiences friction, or drag, as the air and water molecules interact. Small waves increase the roughness of the surface, which augments the drag felt by the atmosphere as the air flows over the waves. This physical interaction between atmosphere and ocean facilitates the exchange of energy and material (e.g., gas) across the ocean surface, as well as drives upper ocean currents. In the presence of large waves, or swell, this interaction becomes more complicated. The impact swell has on the atmosphere changes as these large waves travel into shallow water, thereby growing taller and steeper, however our understanding of this process is limited. We present an observational study that took place within Monterey Bay and our results suggest that typical models used to predict the ocean surface drag do not perform well in the nearshore zone. In fact, applying a shallow water model did not significantly improve model‐observation comparison. We demonstrate that the mechanisms that characterize air‐sea interaction in deep water, may not apply near shore. While coastal zones are limited, compared to the global ocean, their impacts on and response to human activity are profound and should be better understood. Key Points: Measured drag coefficients were 2‐4 times larger than parameterized values, when comparing several modelsGeneralizing a wave‐dependent friction velocity model to arbitrary water depths improved model‐observation agreement to within 30%Consistent wind stress veering off the wind direction was observed and, within 2 km of shore, was associated with surface current variance [ABSTRACT FROM AUTHOR]

This paper describes the use of machine learning methods to build a decision support system for predicting the distribution of coastal ocean algal blooms based on remote sensing data in Monterey Bay. This system can help scientists obtain prior information in a large ocean region and formulate strategies for deploying robots in the coastal ocean for more detailed in situ exploration. The difficulty is that there are insufficient in situ data to create a direct statistical machine learning model with satellite data inputs. To solve this problem, we built a Random Forest model using MODIS and MERIS satellite data and applied a threshold filter to balance the training inputs and labels. To build this model, several features of remote sensing satellites were tested to obtain the most suitable features for the system. After building the model, we compared our random forest model with previous trials based on a Support Vector Machine (SVM) using satellite data from 221 days, and our approach performed significantly better. Finally, we used the latest in situ data from a September 2014 field experiment to validate our model.

Highlights • An integrated deployment of multiple in situ platforms uncovered detailed aspects of population and toxicity dynamics of Pseudo-nitzschia across divergent bloom years in Monterey Bay. • Shifts in Pseudo-nitzschia species composition and abundance leading into the 2015 bloom in Monterey Bay were consistent with observations made further north off Oregon and Washington coasts during the northeast Pacific warm anomaly. Abstract Monterey Bay, California experiences near-annual blooms of Pseudo-nitzschia that can affect marine animal health and the economy, including impacts to tourism and commercial/recreational fisheries. One species in particular, P. australis , has been implicated in the most toxic of events, however other species within the genus can contribute to widespread variability in community structure and associated toxicity across years. Current monitoring methods are limited in their spatial coverage as well as their ability to capture the full suite of species present, thereby hindering understanding of HAB events and limiting predictive accuracy. An integrated deployment of multiple in situ platforms, some with autonomous adaptive sampling capabilities, occurred during two divergent bloom years in the bay, and uncovered detailed aspects of population and toxicity dynamics. A bloom in 2013 was characterized by spatial differences in Pseudo-nitzschia populations, with the low-toxin producer P. fraudulenta dominating the inshore community and toxic P. australis dominating the offshore community. An exceptionally toxic bloom in 2015 developed as a diverse Pseudo-nitzschia community abruptly transitioned into a bloom of highly toxic P. australis within the time frame of a week. Increases in cell density and proliferation coincided with strong upwelling of nutrients. High toxicity was driven by silicate limitation of the dense bloom. This temporal shift in species composition mirrored the shift observed further north in the California Current System off Oregon and Washington. The broad scope of sampling and unique platform capabilities employed during these studies revealed important patterns in bloom formation and persistence for Pseudo-nitzschia. Results underscore the benefit of expanded biological observing capabilities and targeted sampling methods to capture more comprehensive spatial and temporal scales for studying and predicting future events. [ABSTRACT FROM AUTHOR]

Abstract Anthropogenic input of carbon dioxide (CO 2) into the atmosphere and its uptake by the ocean with associated changes in ocean chemistry have created an urgent need to expand coverage of sea surface and atmospheric carbon dioxide observations. Conventional sampling platforms (e.g. ships and moorings) do not provide the spatial and temporal resolution needed to assess the effects of rapidly changing carbon dioxide conditions and are expensive to operate. Through a series of deployments beginning in March 2012, two versions of the Wave Glider autonomous surface vehicles from Liquid Robotics, Inc. have been instrumented with sensors to measure pH, partial pressure of CO 2 (p CO 2) of the atmosphere and sea surface, and wind speed and direction, from which instantaneous sea-air fluxes of CO 2 can be calculated. These deployments, most near Monterey Bay, California, were highly correlated with Δ p CO 2 measurements obtained from the Monterey Bay Aquarium Research Institute's (MBARI) long-term mooring station M1, as well as from shipboard observations. In the central California upwelling system with highly variable p CO 2 levels, the gliders captured large spatial gradients associated with upwelling fronts. Differences in sea surface p CO 2 as large as 470 μ atm over < 0.5 km were observed. Unlike traditional ship sampling methods, however, this new generation of sampling platforms is capable of continuous long-term (months) deployments at a fraction of the cost. The vehicles thus have the potential of filling important gaps in present understanding of the effects of global change on ocean chemistry. [ABSTRACT FROM AUTHOR]

Abstract Sediment traps were deployed at two depths (300 m and 1200 m) off Monterey Bay (36°40′N and 122°25′W, Central California) for 7.3 years (1998–2005). The sediment trap data provided information about the quantity and quality of settling material, and allowed exploration of the relationship of the sinking material with the environmental conditions in this coastal upwelling region. The magnitude and composition of the settling material were highly variable over time. Organic carbon (C org) fluxes ranged between 4–296 mg C m−2 day−1 and 0.1–142 mg C m−2 day−1 for shallow and deep sediment traps, respectively. The time series of C org vertical flux was characterized by pulses of intense fluxes that were associated with peaks of primary production, generally during upwelling periods. Despite considerable variability, fluxes varied seasonally with highest values during the upwelling season and the lowest in winter. Attenuation of C org vertical fluxes with depth (300 m vs. 1200 m) varied between 31% and 24% except for the late upwelling period, when there was an increase with depth likely due to resuspension of material from Monterey Canyon. Calculation of a seasonal vertical budget of organic carbon off Monterey Bay resulted in a transfer between 4.0% and 4.9% of the primary production to the deep ocean, suggesting that coastal upwelling efficiently sequestered CO 2. [ABSTRACT FROM AUTHOR]

Fluvial sediment deposits can provide useful records of integrated watershed expressions including flood event magnitudes. However, floodplain and estuarine sediment deposits evolve through the interaction of watershed/marine sediment supply and transport characteristics with the local depositional environment. Thus extraction of watershed scale signals depends upon accounting for local scale effects on sediment deposition rates and character. This study presents an examination of the balance of fluvial sediment dynamics and local scale hydro-geomorphic controls on alluviation of an abandoned channel in the Salinas River Lagoon, CA. A set of three sediment cores contained discrete flood deposits that corresponded to the largest flood events over the period of accretion from 1969 to 2007. Sedimentation rates scaled with peak flood discharge and event scale sediment flux, but were not influenced by longer scale hydro-meteorological activities such as annual precipitation and water yield. Furthermore, the particle size distributions of flood deposits showed no relationship to event magnitudes. Both the responsiveness of sedimentation and unresponsiveness of particle size distributions to hydro-sedimentological event magnitudes appear to be controlled by aspects of local geomorphology that influence the connectivity of the abandoned channel to the Salinas River mainstem. Well-developed upstream plug bar formation precluded the entrainment of coarser bedload into the abandoned channel, while Salinas River mouth conditions (open/closed) in conjunction with tidal and storm surge conditions may play a role in influencing the delivery of coarser suspended load fractions. Channel adjacent sediment deposition can be valuable records of hydro-meteorological and sedimentological regimes, but local depositional settings may dominate the character of short term (interdecadal) signatures. [ABSTRACT FROM AUTHOR]

The Brandt's Cormorant of the California Current is a “boom-or-bust” species like its congeners in other eastern boundary, upwelling driven ecosystems, and like many of the prey upon which they depend. These birds produce many recruits when fish availability is high, leading to rapidly increasing populations, but few recruits, and may even exhibit die-offs, when the opposite is true. Unlike cormorants in the Peru and Benguela currents, however, Brandt's Cormorant population changes have yet to be correlated with those of its prey. Herein, using multi-decadal time series of cormorant colony size, diet, prey availability and mortality, in the context of changes in breeding site and fishery management, we provide insight into why central California colonies near San Francisco — a major portion of this species' global population — expanded from principally one offshore island in the 1960–70s to include a large mainland component by the 1990s. Involved were increases and decreases, respectively, of northern anchovy, a coastal forage species, and young-of-the year rockfish, more prevalent offshore. With protection of breeding sites and a shift towards ecosystem-based fisheries management by the 1990s, variations of the central California Brandt's Cormorant population are now driven naturally by forage fish availability, and perhaps inter- and intraspecific competition for prey and space when population sizes are high. This species, owing to its “boom-or-bust” natural history and the relative ease of assessing breeding population size and diet, may be ideal for monitoring the state of the central California Current food web. [ABSTRACT FROM AUTHOR]

As a demonstrator for technologies for the next generation of ocean color sensors, the Hyperspectral Imager for the Coastal Ocean (HICO) provides enhanced spatial and spectral resolution that is required to understand optically complex aquatic environments. In this study we apply HICO, along with satellite remote sensing and in situ observations, to studies of phytoplankton ecology in a dynamic coastal upwelling environment—Monterey Bay, CA, USA. From a spring 2011 study, we examine HICO-detected spatial patterns in phytoplankton optical properties along an environmental gradient defined by upwelling flow patterns and along a temporal gradient of upwelling intensification. From a fall 2011 study, we use HICO’s enhanced spatial and spectral resolution to distinguish a small-scale “red tide” bloom, and we examine bloom expansion and its supporting processes using other remote sensing and in situ data. From a spectacular HICO image of the Monterey Bay region acquired during fall of 2012, we present a suite of algorithm results for characterization of phytoplankton, and we examine the strengths, limitations, and distinctions of each algorithm in the context of the enhanced spatial and spectral resolution.

Often in calculating a sediment budget there is an unknown contribution, which is ascribed to the residual of the balance, and the budget cannot be fulfilled. The temporal and spatial variations and sediment size within a littoral cell provide additional information to define sediment budgets. The approach here is to consider only medium to coarse sand (grain size > 0.25 mm) over a long time period during significant changes of natural and anthropogenic inputs and losses that allow calculating several budgets to isolate the unknown inputs and outputs to close the system. Considering only medium to coarse sand eliminates including the cross-shore transport of fine sand by waves, which is poorly quantified. To demonstrate these concepts, shoreline recession rates measured over a 101-year time period are used to calculate sediment budgets for southern Monterey Bay, California, littoral cells. The coarse sandy shoreline is backed by extensive bluffs and dunes that reach 44 m in elevation. Intensive sand mining of coarse sand derived directly from the beach and surfzone started in 1927 and continues today. A contribution of about 100 k m 3 /year of medium to coarse sand from the Salinas River is calculated from measured shoreline accretion for the period 1910–1945 starting when the river first flowed into the littoral cell, prior to damming of the river and significant losses owing to sand mining. Sediment budgets are calculated for 1940–1989 and 1989–2011 to spatially identify the loss of about 200 k m 3 /year attributed to different mining operations that captured the littoral transport. The primary contributions of medium to coarse sand to the littoral system is approximately 180 k m 3 /year from the eroding dunes and beaches. Only a quarter of the dune sand is found to be compatible with the coarser beach sand with the finer fraction carried offshore. A conclusion is that sand mining is the cause of the observed high recession rates. [ABSTRACT FROM AUTHOR]