Rattlesnake Bites in Northern California

In a series of 59 cases of rattlesnake bites at two major northern California hospitals, no deaths occurred, no amputations or fasciotomies were required and only one patient had tissue necrosis requiring a graft.Because patients are being seen in major medical facilities earlier, envenomation is encountered in earlier stages. Less specific national standards of treatment, therefore, should receive less emphasis than treatment based on the virulence of the snakes in the particular geographic region. Initial doses of antivenin given intravenously should be based on the degree of envenomation, with additional titration done for worsening symptoms.     

Enhanced Optical Transmission Through Metallic Holes Array: Role of TE Polarization in SPP Excitation

Optical transmission through double-layer metallic subwavelength holes array is studied under oblique incidence by split-field finite-difference time-domain method. Both TM and TE polarizations are investigated. It is proved that the transmission peaks can also be observed for TE polarization due to the excitation of surface plasmon polaritons (SPP) through diffraction orders. By changing the incident angle, these transmission peaks follow the SPP wavelength shift. The field profiles, even for the field components not present in the incident field, clearly show the SPP excitation. The mechanism of enhanced transmission will be fully discussed.     

Population genetics of colonizing success of weedy rye in Northern California

Summary Genetic parameters of 11 weedy rye populations located in California's northern mountain area and the adjoining Oregon border were compared with those of the putative parents, wild species Secale montamim and cultivated rye S. cereale. All weedy populations exhibited high levels of genetic variation as determined by isozyme analysis. On average, 44% of the isozyme loci were polymorphic, total genetic diversity was 0.30; and number of alleles per locus was 1.65. High genetic identities, averaging 0.994 ± 0.005 between populations, indicated that little genetic differentiation has occurred among these weedy populations since the initial colonization. Lack of population differentiation could be attributed to a wind-pollinated, self-incompatible breeding system resulting in extensive gene flow among weedy populations, and between weedy populations and local cultivars of rye. Multilocus outcrossing rates of weedy populations ranged from 0.86 to 0.97. The estimated levels of gene flow using the private-alleles method were high among weedy populations, and between cv Merced and weedy populations, with estimated Nm values of 14.50 and 8.21, respectively. The colonizing success of weedy rye is discussed and a strategy for its conservation recommended.     

Biological control ofSenecio jacobaea in Northern California,an enduring success

Senecio jacobaea, a poisonous weed from Eurasia, was brought under successful biological control in the Ft. Bragg, California area by 1976, through the combined action of the defoliating cinnabar moth (Tyria jacobaeae) and a root feeding flea beetle (Longitarsus jacobaeae). In 1987, 4 previously infested Ft. Bragg sites (3 sites where control had been documented and another unstudied site) were examined.Senecio jacobaea densities at these sites were 0.0, 0.0, 0.01 and 0.18 plants/m², indicating both continued and improved control of the weed. The flea beetle and the cinnabar moth both persist at the sites, despite very low numbers ofS. jacobaea plants. The control ofS. jacobaea has resulted in the return of near natural vegetation at the 2 coastal prairie sites and regained productivity at the 2 pasture sites. c/o American Embassy APO San Francisco 96301     

The Nematode Heterotylenchus autumnalis and Face Fly Musca autumnalis: A Field Study in Northern California

Helerolylenchus aulumnalis was found in six northern California counties surveyed, and the incitlence of nematode infection of face flies ranged from 4.7 to 43.8%. Intensive studies at a cattle ranch in Yuba County showed that population densities of the host and nematode infections were highest in flies from cow pats receiving full sun. Average host population density was 105.7 puparia per pat, and nematode infection averaged 38.6%. Pats in partial sun averaged 13.5 puparia and 13,1% nematode infection. No face fly was recovered from shaded pats. When data from pats first exposed during day or night were compared, no significant differences in host population density or nematode infection rates were apparent. Uninfected and superinfected flies were more frequent than predicted by a Poisson distribution.Infected and uninfected female flies of all ages captured on white sticky traps appeared to feed with similar frequency upon a creatny substance which was probably acquired from cattle, However, older infected females fed less on blood and more upon dung than older uninfected females. Percent nematode infection and host population densities were highest in spring and early summer, declined to a midsummer low, and then increased slightly. Both dung-reared flies and captured females showed similar trends in abundance anti infection rates. Regression analysis indicated that H. autumnalis may not be regulating face fly population density.     

Large medusae in surface waters of the Northern California Current: variability in relation to environmental conditions

Blooms of jellyfish around the world have been correlated with climatic variables related to environmental causes. Sizeable populations of large medusae, primarily Chrysaora fuscescens and Aequorea sp., appear annually in shelf waters of the Northeast Pacific Ocean. Previous research has shown that C. fuscescens is abundant seasonally in the inner shelf and exhibits high feeding rates on zooplankton. We examined medusae caught in surface trawls over an 8-year period (2000–2007) using (1) mesoscale surveys sampling 8–10 transects in May, June, and September, and (2) biweekly surveys along two transects from April to August, relating abundance to environmental parameters. C. fuscescens abundances generally peaked in late summer, whereas Aequorea sp. peaked in May or June. General additive models of the mesoscale data indicated that station catches for both species correlated with latitude, temperature, salinity, and distance from shore (and chlorophyll a for Aequorea sp.). Analysis of interannual variability revealed that highest catches of medusae correlated with cool spring–summer conditions, or negative anomalies of the Pacific Decadal Oscillation, and low winter–summer runoff from the Columbia River. Results confirmed our hypothesis of connections between jellyfish populations and regional climate conditions in a region known for strong physical forcing of ecosystem processes.     

Spatial and Temporal Examination of Bivalve Communities in Several Estuaries of Southern California and Northern Baja California,MX

A combination of historical bivalve surveys spanning 30–50 years and contemporary sampling were used to document the changes in bivalve community structure over time at four southern California and one northern Baja California estuaries. While there are limitations to the interpretation of historic data, we observed generally similar trends of reduced total bivalve species richness, losses of relatively large and/or deeper-dwelling natives, and gains of relatively small, surface dwelling introduced species across the southern California estuaries, despite fairly distinct bivalve communities. A nearly 50-year absence of bivalves from two wetlands surveyed in a Baja California estuary continued. A combination of site history and current characteristics (e.g., location, depth) likely contributes to maintenance of distinct communities, and both episodic and gradual environmental changes likely contribute to within-estuary temporal shifts (or absences). We highlight future research needed to determine mechanisms underlying patterns so that we can better predict responses of bivalve communities to future scenarios, including climate change and restoration.     

The Sexual Games of the Body Politic: Fantasy and State Violence in Northern Ireland

This article analyzes the practice of strip searching women political prisoners in Northern Ireland as a violent technology of control aimed at breaking the political identity of prisoners. Focusing on acontroversial case of a mass strip search carried out in 1992, thearticle examines the phantasmatic investements pervading this seeminglyrational technology of control. Using a psychoanalytic notion of fantasyagainst the backdrop of a Foucaultian theory of power, this articleargues that strip searches constitute a gendered form of politicaldomination driven by, and performed within, a phantasmatic scenario ofsexual violence. In this scenario both the political and genderidentities of prisoners are re-inscribed with the power of a stateacting as a male body politic. The article argues that the phantasmaticsupport of rational technologies of control betrays the contingent andshifting character of domination as well as its ambiguous effects.     

Campylobacter insulaenigrae Isolates from Northern Elephant Seals (Mirounga angustirostris) in California

There are only two reports in the literature demonstrating the presence of Campylobacter spp. in marine mammals. One report describes the isolation of a new species, Campylobacter insulaenigrae sp. nov., from three harbor seals (Phoca vitulina) and a harbor porpoise (Phocoena phocoena) in Scotland, and the other describes the isolation of Campylobacter jejuni, Campylobacter lari, and an unknown Campylobacter species from northern elephant seals (Mirounga angustirostris) in California. In this study, 72 presumptive C. lari and unknown Campylobacter species strains were characterized using standard phenotypic methods, 16S rRNA PCR, and multilocus sequence typing (MLST). Phenotypic characterization of these isolates showed them to be variable in their ability to grow either at 42°C or on agar containing 1% glycine and in their sensitivity to nalidixic acid and cephalothin. Based on both 16S rRNA PCR and MLST, all but 1 of the 72 isolates were C. insulaenigrae, with one isolate being similar to but distinct from both Campylobacter upsaliensis and Campylobacter helveticus. Phylogenetic analysis identified two C. insulaenigrae clades: the primary clade, containing exclusively California strains, and a secondary clade, containing some California strains and all of the original Scottish strains. This study demonstrates the inability of phenotypic characterization to correctly identify all Campylobacter species and emphasizes the importance of molecular characterization via 16S rRNA sequence analysis or MLST for the identification of Campylobacter isolates from marine mammals.     

Zooplankton species composition is linked to ocean transport in the Northern California Current

In the Northern California Current (NCC), zooplankton communities show interannual and multiyear shifts in species dominance that are tracked by survival of salmon populations. These zooplankton community changes correlate with the Pacific Decadal Oscillation (PDO) index: a ‘warm‐water’ copepod species group is more abundant during warm (positive) phases of the PDO and less abundant during cold (negative) phases; the reverse occurs for a ‘cold‐water’ species group. The observed relationship led to the hypothesis that the relative dominance of warm/cold‐water copepods in the NCC is driven by changes in the horizontal advection of surface water over different phases of the PDO. To test this hypothesis, variation in surface water advection to coastal regions of the NCC over the period of 1950–2008 was investigated using a Regional Ocean Modeling System (ROMS) and passive tracer experiments, then was compared with zooplankton collected off Oregon since 1996. Results showed that surface water advection varied with the phase of the PDO; the low‐frequency component of advection anomalies strongly correlated with copepod species composition (R>0.9). During positive phases of the PDO, current anomalies were northward and onshore, resulting in transport of warmer waters and the associated copepods into the region. During negatives phases, increased equatorward current anomalies led to a copepod community that was dominated by cold‐water taxa. Our results support the hypothesis that climate‐driven changes in basin‐scale circulation controls copepod community composition in the NCC, and demonstrate that large‐scale climate forcings downscale to influence local and regional ecosystem structure.     

Yellow Bush Lupine Invasion in Northern California Coastal Dunes II. Mechanical Restoration Techniques

Invasion of coastal dunes by Lupinus arboreus (yellow bush lupine) results in soil enrichment and displacement of native plants. Restoration by means of heavy equipment was tested as an alternative to costly manual techniques in a heavily invaded area of relatively flat terrain. Two experiments were conducted in consecutive years at the Eureka Dunes Protected Area in Humboldt County, California. Each experiment consisted of three plots subjected to one of three primary treatments: removal of vegetation with a brush rake, removal of vegetation with a brush rake followed by removal of litter and duff with a plough blade or bucket, and removal of vegetation with tractor-pulled chokers. Plots were then subdivided into smaller secondary treatment plots subjected to one of two treatments or a control. Secondary treatments consisted of weedmat placed for a 1- or 2-year duration. The goal of the treatments was to remove and prevent reestablishment of nonnative vegetation, including but not limited to bush lupine; success was measured by percent cover of recolonizing vegetation 1.5 years after treatment ended. In the first experiment, primary treatment (vegetation removal) but not secondary (prevention of reestablishment) resulted in significant differences in cover by the end of the experiment. The brush rake and plough blade treatment was most successful at preventing reestablishment of nonnative vegetation. In the second experiment, secondary treatment (prevention of reestablishment) but not primary (removal of vegetation) resulted in significant differences at the end of the experiment. Re-invasion increased with the amount of time subplots were left uncovered. The difference in the results of the first and second experiments was attributed to variation in rainfall and, to a lesser extent, to localized variation in species composition. Results suggest that mechanical restoration by means of combination of the brush rake and plough blade primary treatment with the 2-year weedmat secondary treatment would be most successful in meeting the dual goals of removal of nonnative vegetation and prevention of its reestablishment.     

Invasion of an annual grassland in Northern California by Baccharis pilularis ssp. consanguinea

Summary We studied the invasion of a California annual grassland by the shrub, Baccharis pilularis ssp. consanguinea (DC) C.B. Wolf. A series of aerial photographs indicated that the shrub had been present at the study site for 35–45 years but spread very little until the early 1970's. A period of slow expansion was followed by rapid outward spread of the shrub population and large increases in shrub density. Detailed demographic studies showed a period of rapid population increase from 1978 to 1983, with the highest stablishment rates in 1982–83. Establishment was strongly correlated with annual and spring rainfall amounts. An iniiall period of slow outward spread is thought to have profided foci for rapid spread during years of high rainfall.     

Major and Trace Elements in Zooplankton from the Northern Gulf of California During Summer

We report the distribution of major and trace element concentrations in epipelagic zooplankton collected in the Northern Gulf of California in August 2003. The Bray–Curtis index defined three element assemblages in zooplankton: (1) major metals, which included only two elements, Na (3.6–17.0%) and Ca (1.0–4.8%). Na had its highest concentrations in the shallow tidally mixed Upper Gulf, where high salinity, temperature, and zooplankton biomass (dominated by copepods) prevailed. Ca showed its highest concentrations south of Ballenas Channel, characterized by tidal mixing and convergence-induced upwelling, indicated by low sea-surface temperature, salinity, and zooplankton biomass; (2) Six biological essential elements, like Fe (80–9,100 mg kg⁻¹) and Zn (20–2,570 mg kg⁻¹), were detected in high concentrations in zooplankton collected near Guaymas Basin, which had high surface temperature and chlorophyll a concentrations. (3) Metals of terrigenous origin, such as Sc (0.01–1.4 mg kg⁻¹) and Th (0.03–2.3 mg kg⁻¹), and redox-sensitive metals, like Co (3–23.8 mg kg⁻¹); this was the assemblage with the largest number of elements (15). Both types of elements of assemblage 3 had maximum concentrations in the cyclonic eddy that dominates the summer circulation in the Northern region. We concluded that sediment resuspension by tidal mixing in the Upper Gulf, upwelling south of Ballenas Channel, and the cyclonic eddy were key oceanographic features that affected the element concentrations of epipelagic zooplankton in the Northern Gulf of California. Oceanographic mechanisms such as these may contribute to element incorporation in marine organisms in other seas.