Articles

Published journal articles by MLML faculty, staff and students. Full text is included when copyright allows.


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Comparative feeding ecology of four sympatric skate species off central California, USA
Comparative feeding ecology of four sympatric skate species off central California, USA
The big (Raja binoculata), California (R. inornata), longnose (R. rhina), and sandpaper (Bathyraja kincaidii), skates are commonly found on soft-bottom regions of the central California continental shelf and upper slope. The feeding ecology of this assemblage was compared to evaluate the degree of trophic separation among species, based on the results of previous species-specific diet studies. Specimens were collected from fishery independent trawl surveys conducted during September 2002-March 2003 at depths of 9-536 m. Using single and compound measures, diet composition of small (≤60 cm TL) and large (>60 cm TL) individuals were compared within continental shelf (≤200 m) and slope (>200 m) regions using traditional, multivariate, and novel techniques. Diet compositions within size classes were similar in both regions. Diet compositions between size classes generally differed, however, with fishes more important and crustaceans (especially shrimps and euphausiids) less important in the diets of large individuals. Crabs contributed substantially to skate diet compositions on the shelf, but were uncommon prey items at deeper depths, probably because of their relative scarcity in slope waters. Conversely, cephalopods were common prey items at slope depths, but were rarely ingested at shelf depths. The studied skate assemblage appears to consist primarily of generalist crustacean and fish predators that exhibit high dietary overlap at similar sizes. It is possible that resource competition among skates and groundfish species has been reduced because of considerable recent declines in the biomass of upper trophic level groundfishes. Skates may therefore play important roles in contemporary benthic food web dynamics off central California. © 2007 Springer Science+Business Media, Inc., Cited By (since 1996):30 Fish and Fisheries, CODEN: EBFID
Comparative phosphate acquisition in giant-celled rhizophytic algae (Bryopsidales, Chlorophyta)
Comparative phosphate acquisition in giant-celled rhizophytic algae (Bryopsidales, Chlorophyta)
Phosphate uptake through above-ground thalli vs. subterranean rhizoids has been compared in siphonaceous rhizophytic green algal species from five globally distributed tropical genera: Avrainvillea nigricans Decaisne, Caulerpa lanuginosa J. Agardh, Halimeda incrassata (J. Ellis) J.V. Lamouroux, Penicillus capitatus Lamarck, and Udotea flabellum (J. Ellis & Solander) M. Howe. Plants were collected, acclimated to lab conditions for 3 days, and then incubated for 8 h at saturating light intensity with 30 μM PO43- added to their above-ground thallus or below-ground rhizoids. Percent tissue phosphorus was then compared to control specimens, which were run simultaneously in the absence of phosphate. The two fleshy species, A. nigricans and C. lanuginosa, showed no significant differences in tissue nutrient status, and displayed much larger variation among controls than the three calcified species. Calcified species showed greater phosphorus content after being exposed to either above- or below-ground thallus portions, indicating that these seaweeds can respond to short term increases in nutrient availability and have a more regulated nutrient acquisition mechanism. Results suggest that calcification may play an important role in phosphorus absorption. © 2009 Elsevier B.V., Cited By (since 1996):2 Seaweeds, CODEN: AQBOD
Comparative population demography of elasmobranchs using life history tables, Leslie matrices and stage-based matrix models
Comparative population demography of elasmobranchs using life history tables, Leslie matrices and stage-based matrix models
Results of demographic analyses of four species of elasmobranchs were compared by use of life-history tables, Leslie matrices, and several stage-based matrix models. Dasyatis violacea, with few age classes, was used to demonstrate the basics of Leslie-matrix and stage-based matrix model calculations. The demography for Carcharias taurus, with a 2-year reproductive cycle, produced higher potential population growth using actual fertility rather than effective annual fertility. The demography for Alopias pelagicus, with continuous reproduction, produced higher potential population growth for a birth-flow than a birth-pulse population. The Carcharodon carcharias example demonstrated only a small difference in potential population growth between step-like and logistic fertility functions. Stage-based models with fixed stage duration produced potential population growths identical to those obtained from a life-history table or Leslie matrix, but the net reproductive rates and generation times differed. Stage-based models with few stages had different dynamics with shorter recovery to the stable age distribution; they underestimated the elasticity of juvenile survival and overestimated the elasticity of adult survival, suggesting that interpretation should be cautious. Elasticity analyses were used to estimate the number of juvenile age classes that could be fished and have the same effect on potential population growth as fishing all the adult age classes., Cited By (since 1996):42 Fish and Fisheries, CODEN: AJMFA
Comparative survivorship and life history of painted greenling (Oxylebius pictus) in Puget Sound, Washington and Monterey Bay, California
Comparative survivorship and life history of painted greenling (Oxylebius pictus) in Puget Sound, Washington and Monterey Bay, California
The painted greenling, Oxylebius pictus, a hexagrammid fish of shallow, northeastern Pacific rocky habitats was observed and collected near the center of its range at Monterey Bay, California, and near the northern limit of its distribution at Puget Sound. Life history characteristics were compared for breeding stocks from the two areas. Mean and maximum adult body sizes (lengths and wet weights) and longevities of both sexes are greater at Puget Sound. Also, both males and females reach sexual maturity at a smaller body length at Monterey. Age group 0 and I juveniles are twice as abundant as adults at Monterey but rare at Puget Sound. Monterey females have greater relative fecundities. Egg development rates are similar at equivalent temperatures; eggs are smaller, however, at Monterey, and thus embryos are smaller at hatching. Length increase is faster for Puget Sound juveniles; adult fish in the two areas grow in length at comparable rates, although weight per body length is consistently greater for Monterey fish. These findings reflect a poorer survivorship at Monterey, where natural predation on fertilized eggs and the mortality rates of adult males are greater. © 1980 Dr. W. Junk B.V. Publishers., Cited By (since 1996):7 Fish and Fisheries, CODEN: EBFID
Comparing sea level response at Monterey, California from the 1989 Loma prieta earthquake and the 1964 great Alaskan earthquake
Comparing sea level response at Monterey, California from the 1989 Loma prieta earthquake and the 1964 great Alaskan earthquake
Two of the largest earthquakes to affect water levels in Monterey Bay in recent years were the Loma Prieta Earthquake (LPE) of 1989 with a moment magnitude of 6.9, and the Great Alaskan Earthquake (GAE) of 1964 with a moment magnitude of 9.2. In this study, we compare the sea level response of these events with a primary focus on their frequency content and how the bay affected it, itself. Singular Spectrum Analysis (SSA) was employed to extract the primary frequencies associated with each event. It is not clear how or exactly where the tsunami associated with the LPE was generated, but it occurred inside the bay and most likely began to take on the characteristics of a seiche by the time it reached the tide gauge in Monterey Harbor. Results of the SSA decomposition revealed two primary periods of oscillation, 9-10 minutes, and 31-32 minutes. The first oscillation is in agreement with the range of periods for the expected natural oscillations of Monterey Harbor, and the second oscillation is consistent with a bay-wide oscillation or seiche mode. SSA decomposition of the GAE revealed several sequences of oscillations all with a period of approximately 37 minutes, which corresponds to the predicted, and previously observed, transverse mode of oscillation for Monterey Bay. In this case, it appears that this tsunami produced quarter-wave resonance within the bay consistent with its seiche-like response. Overall, the sea level responses to the LPE and GAE differed greatly, not only because of the large difference in their magnitudes but also because the driving force in one case occurred inside the bay (LPE), and in the second, outside the bay (GAE). As a result, different modes of oscillation were excited., Cited By (since 1996):4
Comparison of inherent optical properties as a surrogate for particulate matter concentration in coastal waters
Comparison of inherent optical properties as a surrogate for particulate matter concentration in coastal waters
Particulate matter concentration (PM, often referred to as total suspended solids [TSS]) is an important parameter in the evaluation of water quality. Several optical measurements used to provide an estimate of water turbidity have also been used to estimate PM, among them light transmission, backscattering, and side-scattering. Here we analyze such measurements performed by the Alliance for Coastal Technologies (ACT) at various coastal locations to establish whether a given optical method performs better than others for the estimation of PM. All the technologies were found to perform well, predicting PM within less than 55% relative difference for 95% of samples (n = 85, four locations). Backscattering performed best as a predictor of PM, predicting PM with less than 37% relative difference for 95% of samples. The correlation coefficient (R) was between 0.96 and 0.98 for all methods with PM data ranging between 1.2 to 82.4 g m -3. In addition, co-located measurements of backscattering and attenuation improves PM prediction and provides compositional information about the suspended particles; when their ratio is high, the bulk particulate matter is dominated by inorganic material while when low, dominated by organic material. © 2009, by the American Society of Limnology and Oceanography, Inc., Cited By (since 1996):17
Comparison of marine sediment toxicity test protocols for the amphipod Rhepoxynius abronius and the polychaete worm Nereis (Neanthes) arenaceodentata
Comparison of marine sediment toxicity test protocols for the amphipod Rhepoxynius abronius and the polychaete worm Nereis (Neanthes) arenaceodentata
The 10-d amphipod survival toxicity test protocol using Rhepoxynius abronius was compared to the 20-d polychaete worm growth and survival protocol using Nereis (Neanthes) arenaceodentata. Of the 341 sediment samples collected in California and tested over a 2-year period, 78% significantly inhibited R. abronius survival, whereas 2 and 26% significantly inhibited N. arenaceodentata survival and biomass, respectively. Statistical power associated with each protocol endpoint was determined by calculating the minimum significant difference (MSD) for each test protocol for this data set. The 90th percentile MSDs for R. abronius survival and N. arenaceodentata survival and biomass were 16, 36, and 56%, respectively. Survival of R. abronius was significantly negatively correlated with a number of toxicants including metals, pesticides, polycyclic aromatic hydrocarbons, and polychlorinated bipbenyls. No significant correlations were determined between N. arenaceodentata survival or biomass and contaminants measured. Amphipod survival was also negatively correlated with sediment total organic carbon and grain size, but when samples with a high percent fine grain size (>90% fines) were eliminated from consideration, the overall conclusions of the study were not altered. The 10-d amphipod survival protocol using R. abronius was a more sensitive indicator of toxicity, but the results indicate that this was due to greater statistical power rather than greater sensitivity of the test organisms or endpoints., Cited By (since 1996):16
Comparison of seastar (Asteroidea) fauna across island groups of the Scotia Arc
Comparison of seastar (Asteroidea) fauna across island groups of the Scotia Arc
The Antarctic shelf fauna is isolated from other continental shelf faunas both physically by distance, and oceanographically by the Antarctic circumpolar current (ACC). To elucidate the relative importance of these two isolating mechanisms, we used the seastar fauna of the south-Atlantic sub-Antarctic islands to address the hypothesis that the ACC is dominant in controlling the distribution pattern of Antarctic fauna. We expected that seastar faunas from islands on the high latitude side of the ACC would show more similarities to each other than to faunas from islands on the low latitude side. The alternative isolation by distance model predicted that the island furthest from others would have the most unique fauna. For shelf-depth (<500 m) Asteroidea of the Scotia Arc region, assemblages were more similar between islands on each side of the ACC barrier than islands that were closer together, and this pattern was caused by differences in abundance of a few ubiquitous species. © 2006 Springer-Verlag., Cited By (since 1996):3 Invertebrates
Comparison of techniques used to count single-celled viable phytoplankton
Comparison of techniques used to count single-celled viable phytoplankton
Four methods commonly used to count phytoplankton were evaluated based upon the precision of concentration estimates: Sedgewick Rafter and membrane filter direct counts, flow cytometry, and flow-based imaging cytometry (FlowCAM). Counting methods were all able to estimate the cell concentrations, categorize cells into size classes, and determine cell viability using fluorescent probes. These criteria are essential to determine whether discharged ballast water complies with international standards that limit the concentration of viable planktonic organisms based on size class. Samples containing unknown concentrations of live and UV-inactivated phytoflagellates (Tetraselmis impellucida) were formulated to have low concentrations (<100 mL -1) of viable phytoplankton. All count methods used chlorophyll a fluorescence to detect cells and SYTOX fluorescence to detect nonviable cells. With the exception of one sample, the methods generated live and nonviable cell counts that were significantly different from each other, although estimates were generally within 100% of the ensemble mean of all subsamples from all methods. Overall, percent coefficient of variation (CV) among sample replicates was lowest in membrane filtration sample replicates, and CVs for all four counting methods were usually lower than 30% (although instances of ~60% were observed). Since all four methods were generally appropriate for monitoring discharged ballast water, ancillary considerations (e.g., ease of analysis, sample processing rate, sample size, etc.) become critical factors for choosing the optimal phytoplankton counting method. © 2011 Springer Science+Business Media B.V. (outside the USA)., Cited By (since 1996):1 Seaweeds, CODEN: JAPPE
Complementarity in marine biodiversity manipulations: Reconciling divergent evidence from field and mesocosm experiments
Complementarity in marine biodiversity manipulations: Reconciling divergent evidence from field and mesocosm experiments
Mounting concern over the loss of marine biodiversity has increased the urgency of understanding its consequences. This urgency spurred the publication of many short-term studies, which often report weak effects of diversity (species richness) driven by the presence of key species (the sampling effect). Longer-term field experiments are slowly accumulating, and they more often report strong diversity effects driven by species complementarity, calling into question the generality of earlier findings. However, differences among study systems in which short- and long-term studies are conducted currently limit our ability to assess whether these differences are simply due to biological or environmental differences among systems. In this paper, we compared the effect of intertidal seaweed species richness on biomass accumulation in mesocosms and field experiments using the same pool of species. We found that seaweed species richness increased biomass accumulation in field experiments in both short (2-month) and long (3-year) experiments, although effects were stronger in the longterm experiment. In contrast, richness had no effect in mesocosm experiments, where biomass accumulation was completely a function of species identity. We argue that the short-term experiments, like many published experiments on the topic, detect only a subset of possible mechanisms that operate in the field over the longer term because they lack sufficient environmental heterogeneity to allow expression of niche differences, and they are of insufficient length to capture population-level responses, such as recruitment. Many published experiments, therefore, likely underestimate the strength of diversity on ecosystem processes in natural ecosystems. © 2008 by The National Academy of Sciences of the USA., Cited By (since 1996):33 Seaweeds, CODEN: PNASA
Complementary sampling methods to inform ecosystem-based management of nearshore fisheries
Complementary sampling methods to inform ecosystem-based management of nearshore fisheries
Area-based fishery management and ecosystem-based management strategies are considered beneficial marine resource management tools, but they require finite information about the structure and function of ecosystems to evaluate populations and describe the effects of fishing on ecosystems. The required information is not likely to be obtained from sporadic, fishery-dependent data collected from data-poor fisheries, and funding constraints preclude extensive fishery-independent surveys. This situation has led to an interest in relating or combining information from a variety of disparate sampling methods. From 2003 to 2006, we investigated the relationships between estimates of catch per unit effort (CPUE) and the abundance of fishes generated from typical nearshore commercial fishing operations and estimates of density and abundance derived from scuba surveys in the same locations. The relationships between CPUE and the density estimates derived from different sampling methods were found to be statistically significant in the case of many of the common species sampled across sites in Carmel Bay, California. The compounding effects of within-sample variance and the error associated with the regression equations, however, would result in poor confidence in the values translated from one sampling method to another. Different sampling methods may provide reasonable estimates of population trends, but they are sufficiently different and variable as to preclude the use of a scaling factor to standardize population estimates among sampling methods. Also, the differences in species composition (i.e., relative CPUE or density among species) produced by each sampling method were significant and were also affected by habitat relief and sample depth. Nonetheless, our results suggest the value of a cost-benefit analysis that would allow managers to design optimal sampling strategies for characterizing CPUE relationships within a region of interest. A sampling program that benefits from the complementary strengths of fishing gear and scuba sampling will probably result in the most comprehensive description of nearshore fish assemblages. © American Fisheries Society 2010., Cited By (since 1996):3 Fish and Fisheries
Composition and fluxes of submarine groundwater along the Caribbean coast of the Yucatan Peninsula
Composition and fluxes of submarine groundwater along the Caribbean coast of the Yucatan Peninsula
Submarine groundwater discharge (SGD) to the coastal environment along the eastern Yucatan Peninsula, Quintana Roo, Mexico was investigated using a combination of tracer mass balances and analytical solutions. Two distinct submarine groundwater sources including water from the unconfined surficial aquifer discharging at the beach face and water from a deeper aquifer discharging nearshore through submarine springs (ojos) were identified. The groundwater of nearshore ojos was saline and significantly enriched in short-lived radium isotopes (223Ra, 224Ra) relative to the unconfined aquifer beach face groundwater. We estimated SGD from ojos using 223Ra and used a salinity mass balance to estimate the freshwater discharge at the beach face. Analytical calculations were also used to estimate wave set-up and tidally driven saline seepage into the surf zone and were compared to the salinity-based freshwater discharge estimates. Results suggest that average SGD from ojos along the Yucatan Peninsula Caribbean coast is on the order of 308 m3 d−1 m−1 and varies between sampling regions. Higher discharge was observed in the southern regions (568 m3 d−1 m−1) compared to the north (48 m3 d−1 m−1). Discharge at the beach face was in the range of 3.3–8.5 m3 d−1 m−1 for freshwater and 2.7 m3 d−1 m−1 for saline water based on the salinity mass balance and wave- and tidally-driven discharge, respectively. Although discharge from the ojos was larger in volume than discharge from the unconfined aquifer at the beach face, dissolved inorganic nitrogen (DIN) was significantly higher in beach groundwater; thus, discharge of this unconfined beach aquifer groundwater contributed significantly to total DIN loading to the coast. DIN fluxes were up to 9.9 mol d−1 m−1 from ojos and 2.1 mol d−1 m−1 from beach discharge and varied regionally along the 500 km coastline sampled. These results demonstrate the importance of considering the beach zone as a significant nutrient source to coastal waters for future management strategies regarding nutrient loading to reef environments and coastal development. This study also identifies the importance of understanding the connectivity of submarine spring discharge to the nearshore coastal environment and the impact of inland anthropogenic activities may have on coastal health., published
Composition, distribution, and abundance of deep-water (>30 m) macroalgae in central California
Composition, distribution, and abundance of deep-water (>30 m) macroalgae in central California
The deep-water macroalgal assemblage was described at 14 sites off the central California coast during 1999 and 2000 from SCUBA and remotely operated vehicle sampling. The stipitate kelp Pleurophycus gardneri Setchell & Gardner, previously thought to be rare in the region, was abundant from 30 to 45 m, forming kelp beds below the well-known giant kelp forests. Macroalgae typically formed three broadly overlapping zones usually characterized by one or a few visually dominant taxa: 1) the upper "Pleurophycus zone" (30-45 m) of stipitate kelps and Desmarestia spp. with a high percent cover of corallines, low cover of uncalcified red algae, and rare green algae; 2) a middle "Maripelta zone" (40-55 m) with other uncalcified red algae and infrequent corallines and green algae; and 3) a zone (55-75 m) of infrequent patches of non-geniculate coralline algae. The green alga Palmophyllum umbracola Nelson & Ryan, not previously reported from the Northeast Pacific, was found over the entire geographical range sampled from 35 to 54 m. Year-round profiles of water column irradiance revealed unexpectedly clear water with an average K0 of 0.106·m-1. The low percent surface irradiance found at the average lower macroalgal depth limits in this study (0.56% for brown algae, 0.12% for uncalcified red algae, and 0.01% for nongenictilate coralline algae) and lack of large grazers suggest that light controls the lower distributional limits. The ubiquitous distribution, perennial nature, and similar lower depth limits of deep-water macroalgal assemblages at all sites suggest that these assemblages are a common persistent part of the benthic biota in this region., Cited By (since 1996):26 Seaweeds, CODEN: JPYLA
Composition, export and faunal utilization of drift vegetation in the salt river submarine canyon
Composition, export and faunal utilization of drift vegetation in the salt river submarine canyon
Submarine canyons may be particularly important in the transport process of drift seagrasses and seaweeds from highly productive shallow lagoon areas to deeper water. We studied the composition, export, and faunal utilization of shallow, nearshore benthic vegetation as it was transported to offshore areas via the Salt River submarine canyon on the island of St Croix, U.S. Virgin Islands. The study was conducted using a saturation diving system (NULS-1: Hydrolab) during two missions in April and August, 1980. Using bottom drifters deployed in Salt River Bay and the submarine canyon, we recorded net benthic current flow up to 2 cm s-1 moving out of the lagoon and down the canyon to deeper water. Using bottom nets set up at the canyon head and at the 29 m isobar, and from transect surveys and drift clump samples, we determined drift plant export rates and drift clump biomass and species composition. The dominant drift plants were Thalassia testudinum and Syringodium filiforme and algae in the genera Dictyota, Dictyopterus, and Diloplus. During the second mission, the seagrass Halophila decipiens became more abundant, both in the drift and in large patches along the canyon floor. In both missions, more drift was collected in the nets during high wind conditions than during calmer days. Calculated turnover times ranged from 0·01 to 4·4 days for algae in the order Dictyotales and 4·4 to 18 days for Thalassia blades. Total exported biomass of drift vegetation varied between 1·4 to 65·1 kg wet wt day-1. Samples of drift vegetation contained mostly juvenile forms of both invertebrates and fishes, but in relatively low numbers. Faunal numbers were most strongly related to rate of drift movement. © 1983., Cited By (since 1996):18 Seaweeds, CODEN: ECSSD
Condensation of the isoprenoid and amino precursors in the biosynthesis of domoic acid
Condensation of the isoprenoid and amino precursors in the biosynthesis of domoic acid
Understanding how environmental signals regulate production of domoic acid in blooms of Pseudo-nitzschia spp. at a molecular level requires description of the biochemical pathway to this kainoid neurotoxin. Precursor feeding studies have suggested domoic acid arises from the condensation of the C 10 isoprenoid geranyl diphosphate with glutamate, but the specific reactions leading to domoic acid from these precursors remain undescribed. Here, we develop a method to derivatize domoic acid with propyl chloroformate that enables gas chromatography-mass spectrometry (GC-MS) analysis to measure incorporation of stable isotopes into domoic acid generated in cultures incubated with isotopically-labeled substrates. We apply this method to demonstrate that both 2H from [1- 2H 2]geraniol are incorporated into domoic acid, suggesting that the condensation of geranyl diphosphate with an amino group occurs by nucleophilic substitution of the diphosphate rather than by oxidation of geraniol to the aldehyde before reaction with an amino group to form an imine. Ultimately, these and similar studies will facilitate the identification of DA biosynthetic enzymes and genes which will enable the study of how environmental factors regulate DA biosynthesis at the molecular level. © 2011 Elsevier Ltd., Seaweeds, CODEN: TOXIA
Confirmation of the cookiecutter shark, Isistius brasiliensis, from the eastern North Pacific Ocean (Squaliformes Dalatiidae)
Confirmation of the cookiecutter shark, Isistius brasiliensis, from the eastern North Pacific Ocean (Squaliformes Dalatiidae)
The cookiecutter shark, Isistius brasiliensis, is confirmed for the first time from the eastern North Pacific Ocean. The shark, a female 432 mm in total length, was caught in a sablefish pot at a depth of 1132 m off San Nicolas Island, California, USA (32°59′05″N 120°25′99″W).
Confronting multicollinearity in ecological multiple regression
Confronting multicollinearity in ecological multiple regression
The natural complexity of ecological communities regularly lures ecologists to collect elaborate data sets in which confounding factors are often present. Although multiple regression is commonly used in such cases to test the individual effects of many explanatory variables on a continuous response, the inherent collinearity (multicollinearity) of confounded explanatory variables encumbers analyses and threatens their statistical and inferential interpretation. Using numerical simulations, I quantified the impact of multicollinearity on ecological multiple regression and found that even low levels of collinearity bias analyses (r ≥ 0.28 or r2 ≥ 0.08), causing (1) inaccurate model parameterization, (2) decreased statistical power, and (3) exclusion of significant predictor variables during model creation. Then, using real ecological data, I demonstrated the utility of various statistical techniques for enhancing the reliability and interpretation of ecological multiple regression in the presence of multicollinearity., Cited By (since 1996):503, CODEN: ECOLA
Consistent long-term spatial gradients in replenishment for an island population of a coral reef fish
Consistent long-term spatial gradients in replenishment for an island population of a coral reef fish
The population replenishment of marine organisms is routinely characterized as highly variable and unpredictable in space and time. Using island-wide recruitment surveys of a common coral reef fish, the bluehead wrasse Thalassoma bifasciatum, in 6 summers spanning a 12 yr period (1991 to 2003), we examined whether spatial patterns of recruitment are consistent or variable through time on St. Croix, US Virgin Islands. Despite annual fluctuations in the magnitude of replenishment, recruitment intensity follows a distinct and consistent spatial gradient that differs in direction between the north (leeward) and south (windward) shores; recruitment declines from west to east on the north shore and east to west on the south shore. The rank ordering of sites on each shore was concordant when recruitment was either pooled across years (monthly variation) or pooled across months (annual variation). When the 2 highest recruitment sites on each shore were considered alone, consistent seasonal effects were also apparent, with higher recruitment from June through August on the north shore, and higher recruitment in September on the south shore. Thus, while the magnitude of recruitment is indeed variable in space and time, its qualitative pattern is predictable in this area. Results of prior investigations of larval dispersal and coastal oceanography around St. Croix shed light on the origin of the consistent recruitment patterns documented in this study. The potential for consistent spatial and temporal patterns in recruitment is an important consideration in the spatial management of marine resources.
Construction of digital potential marine benthic habitat maps using a coded classification scheme and its application
Construction of digital potential marine benthic habitat maps using a coded classification scheme and its application
Recent advancements in remote-sensing geophysical technology have enabled the imaging of deep seafloor regions, and the construction of detailed maps depicting potential marine benthic habitats. The recent and severe declines in many groundfish stocks, and the degradation of associated seafloor habitats make these maps of critical importance to the identification of essential fish habitat, and the facilitation of habitat-based management, through the establishment of marine protected areas. However no standard approach to mapping deep-water (>30 m) marine benthic habitats has been established and endorsed by the scientific community, even though several different deep-water habitat characterization schemes exist or are evolving. In this paper, a classification scheme, including an attribute code, for mapping potential marine benthic habitats is presented in an attempt to establish a standard technique to facilitate reproducibility of habitat designations and comparisons of deep-water marine benthic habitats worldwide. This scheme has been developed over more than 15 years of mapping seafloor habitats. One of the main strengths of the scheme is versatility and ease of use because it can be applied to any seafloor environment and is directly adaptable to use with Geographic Information System (GIS) programs. The habitat-mapping scheme presented here is based on physiography and scale, induration (hardness of substrate), and geomorphology. The attribute code associated with this scheme consists of seven primary characters that can be used to represent: 1) physiography and depth (i.e., megahabitat), 2) substrate induration, 3) geomorphology (i.e., meso- and macrohabitat), 4) modifiers for texture, lithology, bedform and biology, 5) seafloor slope or inclination, 6) seafloor rugosity, and 7) geological unit, represented by standard geological symbols. The latter three characters are optional and are included only when slope and rugosity can be calculated and when the geology is known. Further an additional attribute code is presented for use in distinguishing potential habitat types from video and photographic data that consists of two primary characters: 1) geologic or substrate attributes, and 2) biological attributes., Cited By (since 1996):2 Fish and Fisheries
Contaminant Concentrations In Sport Fish From San Francisco Bay
Contaminant Concentrations In Sport Fish From San Francisco Bay
SFEI Contribution #554. San Francisco Estuary Institute, Oakland, CA; Regional Monitoring Program for Water Quality in the San Francisco Estuary. Downloaded from:http://www.sfei.org/sfeireports.htm?page=39&sort=year&order=asc (18 July 2014). 56 pp.
Contaminant Concentrations in Fish from San Francisco Bay, 1997
Contaminant Concentrations in Fish from San Francisco Bay, 1997
A Pilot Study of the San Francisco Estuary Regional Monitoring Program for Trace Substances, San Francisco Estuary Institute. Richmond, CA, 65 pp.
Contaminant Concentrations in Fish from San Francisco Bay, 2003
Contaminant Concentrations in Fish from San Francisco Bay, 2003
SFEI Contribution #432. San Francisco Estuary Institute, Oakland, CA. Downloaded from: http://www.sfei.org/sfeireports.htm?page=32&sort=year&order=as (18 July 2014). 52 pp.

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