Results of the jack mackerel subpopulation discrimination feasibility study

A report is made on the feasibility of discriminating subpopulations of jack mackerel, Trachurus symmetricus, off of the southern California and Baja California coast. Histochemical, morphometric, and meristic characters are compared from four samples of approximately 200 fish each taken from three areas. The data are analyzed for homogeneity by chi-square tests. Heterogeneity was found only in anal fin ray counts. Recommendations for a comprehensive study are made. (16pp.

The chaetognatha of the Eastropic Expedition, with notes as to their possible value as indicators of hydrographic conditions

ENGLISH: The purpose of this study was to investigate the possibility that certain species of Chaetognatha found in Eastern Tropical Pacific waters can serve as biological indicators of oceanographic features. "Indicator" organisms have been found useful in identifying water types, in tracing the pattern of current systems, and in tracing the origin of moving water masses. To be of use in this type of study, the organisms must be sufficiently abundant to be readily sampled, and easily identified to species; they must also, at least partially, fulfill the additional requisites listed and discussed by Sverdrup, Johnson, and Fleming (1942, pp. 866-867). Among several groups of organisms fulfilling these requirements are the Chaetognatha. Specimens of this group of animals occurred in large numbers in the plankton samples used for this study. The works of Thomson (1947), Fraser (1942), Ritter-Zahony (1911), and Sund (1959) were used for identification. SPANISH: El objetivo de este estudio ha sido el de investigar la posibilidad de utilizar ciertas especies de quetognatos encontrados en el Pacífico Oriental Tropical como indicadoras biológicas de características oceanográficas. Organismos "indicadores" fueron encontrados útiles para la identificación de tipos de agua, el trazado del régimen de los sistemas de corrientes y la determinación del origen de masas de agua en movimiento. Para servir a este tipo de estudios, los organismos deben ser lo suficientemente abundantes como para ser fácilmente muestreados e identificados hasta la especie; también deben satisfacer, por lo menos parcialmente, los requerimientos indicados y discutidos par Sverdrup, Johnson y Fleming (1942, pags. 866-867)

Results of Jack Mackerel tagging study, 1971-75

Methods and materials used to tag and recapture jack mackerel, Trachurus symmetricus, off the coast of southern Ca1ifornia and Baja California, Mexico, are described. Tagging, recapture, and movement data resulting from this program are reported. Analysis of these data indicates substantial movement of jack mackerel within the range of the California fishery and suggests a seasonal inshore-offshore movement pattern. (13pp.

RISK RESEARCH AND PUBLIC OUTREACH: A TALE OF TWO CULTURES?

Agricultural economists have been challenged in recent years, by voices inside and outside the profession, to evaluate the integrity of the operational bridge between research and extension activities in the land grant system. This essay investigates links between the work of risk researchers and outreach programs. Survey results indicate that (a) a significant number of risk researchers are involved in extension activities; (b) extension economists are less frequently involved in risk research than their colleagues with no extension appointment; (c) full-time extension economists use less sophisticated risk tools in their outreach efforts than used in their research; and (d) all respondents, regardless of appointment, see a need for more applied risk analysis. Major challenges include a lack of financial support to close the data gap and to conduct relevant applied analysis present major communication challenges.Teaching/Communication/Extension/Profession,

Groundwater Conservation Policy in Agriculture

Transboundary water conflicts between urban and rural populations often center on water use in the agricultural sector. Public officials may select a water conservation policy as the primary tool for reducing agricultural water use with the goal to improve water availability to urban areas and future generations. The Groundwater Management Act of 1980 (GMA) in Arizona was designed, in part, to induce water conservation in irrigated agriculture to sustain economic growth in an arid climate. Our mixed-method evaluation design merges qualitative, interview-based information with an estimated water demand function using panel data. We find that the GMA began with a flawed design and evolved through political circumstances into a ineffective water conservation tool. We explain nearly all water use in Arizona's agricultural sector from 1984-2002 using prices and weather data. We found no statistical evidence that the management plans of the GMA directly contributed to reduced water demand in Arizona's agricultural sector over the study period.Impact assessment, public policy, irrigation, water conservation, Resource /Energy Economics and Policy,

Democratization’s Risk Premium: Partisan and Opportunistic Political Business Cycle Effects on Sovereign Ratings in Developing Countries

We use partisan and opportunistic political business cycle (“PBC”) considerations to develop a framework for explaining election-period decisions by credit rating agencies (“agencies”) publishing developing country sovereign risk-ratings (“ratings”). We test six hypotheses derived from the framework with 482 agency ratings for 19 countries holding 39 presidential elections from 1987-2000. We find that ratings are linked to the partisan orientation of incumbents facing election and to expectations of incumbent victory. Consistent with the framework, rating effects are sometimes greater for right-wing compared to left-wing incumbents, perhaps, because partisan PBC considerations with right-wing (left-wing) incumbents reinforce (counteract) opportunistic PBC considerations.http://deepblue.lib.umich.edu/bitstream/2027.42/39931/3/wp546.pd

DEMOCRACY’S SPREAD: Elections and Sovereign Debt in Developing Countries

We use partisan and opportunistic political business cycle (“PBC”) considerations to develop and test a framework for explaining election-period changes in credit spreads for developing country sovereign bonds. Pre-election bond spread trends are significantly linked both to the partisan orientation of incumbents facing election and to expectations of incumbent victory. Bond spreads for right-wing (leftwing) incumbents increase (decrease) as the likelihood of left-wing (right-wing) challenger victory increases. For right-wing incumbent partisan and opportunistic PBC effects bondholder risk perceptions are mutually reinforcing. For left-wing incumbents partisan PBC effects dominate bondholder risk perceptions compared to opportunistic PBC effects.http://deepblue.lib.umich.edu/bitstream/2027.42/39961/3/wp575.pd