Status of the Pacific sardine (Sardinops sagax) resource and fishery

California Fish and Game Code states that the annual sardine quota can be set at a level greater than 1,000 tons, providing that the level of take allows for continued increase in the spawning population. The primary goal of management as directed by the Code is rehabilitation of the resource, with an added objective of maximizing the sustained harvest. We estimate the sardine population size to have been 353,000 short tons on July 1, 1995. Our estimate was based on output from an integrated stock assessment model called CANSAR (Deriso 1993). CANSAR is a forward-casting age-structured analysis using fishery-dependent and fishery-independent data to obtain annual estimates of sardine abundance, year-class strength and age specific fishing mortality for 1983 through the first semester of 1995. CANSAR couples a simulation model with sardine population dynamics. Non-linear least-squares criteria are used to tune the model to match catch-at-age data and other indices of sardine abundance. To calculate the 1996 fishery quota, we used the harvest formula selected as the preferred option in the draft Coastal Pelagic Species-Fishery Management Plan (CPS-FMP). That formula has undergone extensive scientific and user-group review as part of the Pacific Fishery Management Council's (PFMC) CPS-FMP adoption process and has the endorsement of the fishing industry and the scientific community. Use of this formula will result in a reduced fishing mortality rate compared to the formula used to calculate the quota in 1995. We conclude that it is particularly important to reduce fishing mortality for 1996 because the rates may have been excessive in recent years, especially for older aged sardines. Accordingly, we recommend a 1996 sardine harvest quota of 35,000 short tons. (21pp.

Status of the Pacific Mackerel resource during 1996 management recommendations for the fishery

The California fishery for Pacific mackerel (Scomber japonicus) has declined precipitously since 1990. Statewide landings during 1995 continued the downward trend, and totaled only 9,185 short tons. During the last few years, the principal cause of reduced catches has been low biomass and poor availability on the traditional fishing grounds in southern California waters. Cannery closures since 1993 may have also affected demand. Several sources of information are available on the status of the Pacific mackerel stock, all of which suggest a decline in stock biomass compared to the late 1970's and 1980's. Landing statistics, available since 1978 for both the U.S. and Mexican fisheries, show reduced catches during recent years. Catch rates for the southern California Commercial Passenger Fishing Vessel (CPFV) fleet have also shown declining trends since the 1970's. Other fishery- independent data from spotter pilot aerial observations and California Cooperative Oceanic Fisheries Investigations (CalCOFI) ichthyoplankton surveys indicate lower abundance compared to the early 1980's. We used a tuned virtual population analysis (VPA) model called ADEPT to estimate Pacific mackerel biomass. The model finds the best statistical fit between fishery-based, age-structured biomass estimates and other data from aerial observations, plankton surveys, CPFV catch data, and a spawner-recruit relation. Based on the estimated number of fish in each year class during the last quarter of 1995 (including the 1995 year class), and using certain assumptions for expected fishing mortality during the first half of 1996, we project that the Pacific mackerel biomass will be 52,000 tons at the beginning of the 1996/97 fishing season, on July 1,1996. There is a large degree of uncertainty in our 1996 biomass estimate because the 1995 year class (fish of age one) comprises most of the biomass. The Fish and Game Code specifies that when the biomass is between 20,000 and 150,000 tons, the season's quota shall be 30 percent of the total biomass in excess of 20,000 tons. Using that formula and our projection for July 1,1996, we recommend a commercial fishery quota of 9,600 tons for the 1996/97 fishing season. (26pp.

Status of the Pacific Mackerel resource during 1997 and management recommendations for the fishery

Based on a California Department of Fish and Game (CDFG) projected biomass estimate of 91,200 metric tons for July 1, 1997, the recommended commercial fishery quota for the 1997/98 fishing season is 22,000 metric tons. Age-specific abundance for 1996 was estimated using output from a stock assessment model called ADEPT and certain assumptions about growth and fishing mortality during the first half of 1997. In this year's assessment, abundance estimates made by ADEPT were expanded back in time to cover the 68-year period of 1929 through 1996. The commercial fishery quota recommendation is based upon the prescribed harvest formula for Pacific mackerel that is specified in the California Fish and Game Code. Several sources of information are available for the Pacific mackerel stock, all of which suggest a smaller biomass than was present in the 1980's. Landings from both California and Ensenada, Mexico have sharply decreased and catch rates from the southern California Commercial Passenger Fishing Vessel (CPFV) fleet have declined. Fishery-independent indices of abundance from aerial spotter observations and California Cooperative Oceanic Fisheries Investigations (CalCOFI) ichthyoplankton surveys show similar trends. The 1997 biomass estimate is higher than last year's estimate of 47,160 metric tons because data added to the model this year increased abundance for fish of 1994 and older year classes (age 2+). This year's results indicate there were more fish in the older year classes than estimated in previous assessments. (27pp.

Residues of the Cold War: Emergent Waste Consciousness in Postwar American Culture and Fiction

Residues of the Cold War: Emergent Waste Consciousness in Postwar American Culture and Fiction argues that garbage of the post-World War II period can be read as an index of the Cold War cultural landscape and its structure of feeling. This dissertation treats these remainders as archival materials, documents with a kind of textuality, and suggests that when rendered legible their function as crucial sites of conflicting ideologies and discourses can be recognized. Employing the interdisciplinary methods of ecocriticism and cultural materialism, I read Cold War trash to provide a new account of American Cold War culture and literature by tracing the emergence of household garbage as a significant trope in varying cultural contexts. Considering the material effects of the American Cold War project on American landscapes, I elucidate garbage’s role within Cold War matrices of spatial organization and show how some postwar fiction uses garbage and the discourses of disposal as grounds for a critique of dominant Cold War discourses of gender, consumption, and politics. In analyzing the ways waste is represented in different Cold War spaces in literature—the kitchen, the fallout shelter, public urban and suburban spaces, the sanitary landfill—my project argues that proto-ecological conceptualizations of waste concurrently emerged alongside, and challenged, the dominant discourses of Cold War waste management

Manipulating type-I and type-II Dirac polaritons in cavity-embedded honeycomb metasurfaces

Pseudorelativistic Dirac quasiparticles have emerged in a plethora of artificial graphene systems that mimic the underlying honeycomb symmetry of graphene. However, it is notoriously difficult to manipulate their properties without modifying the lattice structure. Here we theoretically investigate polaritons supported by honeycomb metasurfaces and, despite the trivial nature of the resonant elements, we unveil rich Dirac physics stemming from a non-trivial winding in the light-matter interaction. The metasurfaces simultaneously exhibit two distinct species of massless Dirac polaritons, namely type-I and type-II. By modifying only the photonic environment via an enclosing cavity, one can manipulate the location of the type-II Dirac points, leading to qualitatively different polariton phases. This enables one to alter the fundamental properties of the emergent Dirac polaritons while preserving the lattice structure - a unique scenario which has no analog in real or artificial graphene systems. Exploiting the photonic environment will thus give rise to unexplored Dirac physics at the subwavelength scale

The (In)Stability of Planetary Systems

We present results of numerical simulations which examine the dynamical stability of known planetary systems, a star with two or more planets. First we vary the initial conditions of each system based on observational data. We then determine regions of phase space which produce stable planetary configurations. For each system we perform 1000 ~1 million year integrations. We examine upsilon And, HD83443, GJ876, HD82943, 47UMa, HD168443, and the solar system (SS). We find that the resonant systems, 2 planets in a first order mean motion resonance, (HD82943 and GJ876) have very narrow zones of stability. The interacting systems, not in first order resonance, but able to perturb each other (upsilon And, 47UMa, and SS) have broad regions of stability. The separated systems, 2 planets beyond 10:1 resonance, (we only examine HD83443 and HD168443) are fully stable. Furthermore we find that the best fits to the interacting and resonant systems place them very close to unstable regions. The boundary in phase space between stability and instability depends strongly on the eccentricities, and (if applicable) the proximity of the system to perfect resonance. In addition to million year integrations, we also examined stability on ~100 million year timescales. For each system we ran ~10 long term simulations, and find that the Keplerian fits to these systems all contain configurations which may be regular on this timescale.Comment: 37 pages, 49 figures, 13 tables, submitted to Ap

Historical Catch Data From California's Commercial Passenger Fishing Vessel Fleet: Status and Comparison of Two Sources

Two sources of historical landing data from California's commercial passenger fishing vessel (CPFV) fleet were examined to: 1) assess status and content of each archival data source, 2) identify reporting differences, and 3) evaluate potential usefulness of the data for enhancing resource assessment. Current and historical CPFV logbook data collected by California Department of Fish and Game are described with respect to status, content, and approximate cost of recovering historical data (1936-78) to electronic format. CPFV landing data available from Los Angeles Times, archived in libraries since 1959, are similarly described. CPFV logbook data were compared with observer data from 1985-89 to evaluate accuracy of logbook records. Comparison of catch and effort for major species targeted by southern California CPFV anglers revealed significant relationships between reported and observed catch rates for six of ten species examined. Agreement of catch rate trends validates use of logbook data for measuring relative changes in catch and effort for these sport fish species. Direct comparisons of landings data from CPFV logs and Los Angeles Times fish reports were made for years in which Times data are already available in electronic database format, including 1959, 1967, 1975, 1983, 1991, and 1992. Comparisons of total landings by species among years revealed strong correlations between the two sources for those species (e.g., California barracuda, yellowtail, bonito) most heavily targeted over the entire period. Other species, such as California sheephead, spotted scorpionfish, and ocean whitefish, were underreported or not reported by the Times until recently. Comparison of port-wide total landings of all species (1983, 1991, 1992) revealed varied reports of total catch (all species) between sources among ports and years. Times-logbook landing report comparisons were highly correlated for Los Angeles area ports (r2=0.956), but were also most different in absolute number, with Times reports being an average of 48% higher than logbook totals. Comparison of species landings by port in 1992 revealed additional port-wide differences in reporting between both sources. Historical CPFV logbook records have higher spatial resolution (catch location as opposed to port of landing), span a greater period, and will be cheaper to recover into electronic database format than Times fish reports. Historical Times data have higher temporal resolution (daily v. monthly), but II cost approximately $165,000 to recover as opposed to$11 ,000 for logbook data summaries covering a longer period. Strong correlation between the two sources shows usefulness of Times data for tracking real-time changes in sport catch in southern California. (53pp.

Status of the Pacific mackerel resource and fishery 1994 and 1995

The California fishery for Pacific mackerel, Scomber japonicus, has declined precipitously since 1990, and statewide landings during 1994 totaled only 11,070 short tons. The principal cause of the low catches has been low biomass and poor availability on the traditional fishing grounds in southern California waters. Several sources of information are available on the status of the Pacific mackerel stock. Landing statistics were available since 1978 for both the U.S. and Mexican fisheries, and both fisheries show similar declines during recent years. Other fishery-independent data from aerial observations and plankton surveys (mackerel larvae samples) also show declines in abundance compared to the early 1980's. We used a tuned virtual population analysis (VPA) model called ADEPT to estimate Pacific mackerel abundance. The model finds the best statistical fit between fishery-based age-structured biomass estimates and other data from the aerial observations and the plankton surveys. A model-derived biomass estimate for July 1, 1994 was 71,000 tons. Based on the estimated number of fish in each year class at the end of 1994, and using certain assumptions concerning expected fishing mortality during the first half of 1995, we project that the Pacific mackerel biomass will be 56,000 tons at the beginning of the 1995/96 fishing season, on July 1, 1995. The Fish and Game Code specifies that when the biomass is between 20,000 and 150,000 tons, the season's quota shall be 30 percent of the biomass in excess of 20,000 tons. Using that formula and our projection for July 1, 1995, the commercial fishery quota for the 1995/96 fishing season is 10,800 tons. (21pp.