9,388 research outputs found
Biological characteristics of the catch from the 1986-87 Pacific herring, Clupea harengus pallasi, roe fishery in California
In Tomales Bay, 4-, 5-, and 6-yr-old herring, Clupea harengus pallasi, composed 85% by number of the 1986-87 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 88% of the roundhaul catch, and 4-, 5-, and 6-yr-old herring composed 86% by number of the gill net catch.
The age composition of both the Tomales Bay and San Francisco Bay gill net catch has shifted to primarily 4-, 5-, and 6-yr-old herring.
Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was good, with the 1985 yr class composing 37% of the catch.
The mean length of herring in the San Francisco Bay roundhaul catch decreased to 174 mm BL, and the mean length of the gill net catch decreased to 194 mm BL. The mean length of the Tomales Bay catch also decreased to
197 mm BL.
Average weight at age of Tomales Bay herring is below average for the fourth consecutive year. In San Francisco Bay the average weight at age is above average, even though length at age declined slightly. (20pp.
Biological characteristics of the catch from 1984-85 Pacific herring, Clupea harengus pallasi, roe fishery in California
In Tomales Bay, 5-, 6-, and 7-yr-old herring, Clupea harengus pallasi, composed 75% by number of the 1984-85 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 82% by number of the roundhaul catch, and 5-, 6-, and 7-yr-old herring composed 68% by number of
the gill net catch.
The percent of 4-yr-old herring increased to a record high level in the San Francisco Bay gill net catch.
Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was excellent, with 2-yr-old herring composing 41% of the catch.
The growth rate of herring improved in both Tomales and San Francisco Bays, after the period of poor growth during the recent El Nino, when the weight of herring averaged 20% below normal.
(23pp.
Dynamics of Anisotropic Universes
We present a general study of the dynamical properties of Anisotropic Bianchi
Universes in the context of Einstein General Relativity. Integrability results
using Kovalevskaya exponents are reported and connected to general knowledge
about Bianchi dynamics. Finally, dynamics toward singularity in Bianchi type
VIII and IX universes are showed to be equivalent in some precise sence.Comment: 12 pages, 6 figures, Proceedings of the Albert Einstein Century
International Conference, held in Paris, France, July 18-22, 2005. to be
published in AI
Properties of the asymptotic nA+mB->C reaction-diffusion fronts
We discuss, at the mean-field level, the asymptotic shape of the reaction
fronts in the general nA+mB->C reaction-diffusion processes with initially
separated reactants, thus generalizing to arbitrary reaction-order kinetics the
work done by Galfi and Racz for the case n=m=1. Consequences for the formation
of Liesegang patterns are discussed.Comment: EPJ-TeX, 6 pages, 2 figs included. Statement on tails' decay revised.
References added and correcte
Biomass estimates of Pacific herring, Clupea harengus pallasi, in California from the 1981-82 spawning ground surveys
The spawning biomass of Pacific herring in San Francisco Bay and Tomales Bay was estimated to be 99,495 tons and 7,149 tons, respectively during the 1981-82 season. This is the highest estimate to date for San Francisco Bay and continues a rising trend in abundance. The Tomales Bay population increased to the highest level in 4 years. (22pp.
Biological characteristics of the catch from the 1990-91 Pacific Herring, Clupea pallasi, roe fishery in California
The Tomales-Bodega Bay catch during the past two seasons
has been from the northern part of Bodega Bay, due to the
closure of the Tomales Bay fishery.
In the Tomales-Bodega Bay area, 4-, 5-, and 6-yr-old herring
Clupea pallasi, comprised 79% by number of the 1990-91
season's gill net catch.
The number of 4-yr olds (1987 year class) increased to 21%
of the gill net catch. Four-yr olds are an indicator of recruitment strength into the gill net fishery.
Average length of herring in the Tomales-Bodega Bay area
gill net catch decreased due to a shift to younger herring
in the catch, as well as, poor growth characteristics during
1990.
Herring age and size data obtained from Tomales Bay with a
variable mesh research gill net were similar to data from San Francisco Bay obtained with the same net. All age classes were taken and herring ranged in length from 148 mm to 226 mm.
In San Francisco Bay, the age composition of the gill net
catch was also primarily 4-, 5-, and 6-yr-old herring, which
comprised 79% of the catch. In the round haul fishery 2- and
3-yr-old herring dominated, comprising 72% of the catch.
The average length of herring in the San Francisco Bay gill
net and round haul catches decreased. Both are the lowest
recorded average lengths by the respective gear types except
for the 1983-84 El Nino season.
Observed poor growth characteristics this season are attributed to reduced upwelling off central California in 1990. (26pp.
Biomass estimates of Pacific herring, Clupea harengus pallasi, in California from the 1987-88 spawning-ground surveys
The 1987-88 spawning biomass estimate of Pacific herring,
Clupea harengus pallasi, in San Francisco Bay is nearly
69,000 tons. This is the fourth consecutive year that the
San Francisco Bay population has increased, after reaching a
low point of 40,000 tons in 1984.
In Tomales Bay the 1987-88 herring spawning biomass was
estimated at 2,061 tons. During the past five seasons, the
Tomales Bay spawning biomass has been low in even years and
high in odd years, indicating that spawning herring are not
returning to Tomales Bay consistently.
In San Francisco Bay, over 42,000 tons of herring spawned in
January. Similarly, 90% of Tomales Bay herring spawned in
January. No spawns were found during March in either bay.
For the first time, in San Francisco Bay, no herring spawned
in the Belvedere, Tiburon, or Angel Island areas. In
addition, herring spawning was found in the Oakland-Alameda
area for the first time and over 95% of all spawning occurred in the southern part of San Francisco Bay.
During the past six seasons in San Francisco Bay, over 70% of all spawning escapement has been in the southern part of the bay. For the nine seasons prior to that, 94% of all spawning escapement was in the northern part of the bay. (31pp.
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