Early Life History of Fishes in the San Francisco Estuary and Watershed

2004 ◽  
Keyword(s):  
San Francisco ◽  
Early Life History ◽  
Swim Bladder ◽  
Delta Smelt ◽  
Vitro Fertilization ◽  
Total Length ◽  
History Of ◽  
Newly Hatched Larvae ◽  
Swim Bladder Inflation

<em>Abstract.</em>—Delta smelt <em>Hypomesus transpacificus </em>juveniles caught in the Sacramento–San Joaquin Delta were reared in the laboratory to full sexual maturity, and embryos were obtained by in vitro fertilization and natural spawning in tanks. Duration of embryo development to hatching was 11–13 d at 14.8–16.0°C, with a development rate similar to other <em>Hypomesus</em>. Newly hatched larvae were 5.1–5.7 mm total length and resorbed the yolk sac within 6 d and lipid globule within 10 d. Exogenous feeding on rotifers started 5–6 d posthatch. Delta smelt have indirect development with a prolonged larval phase prior to juvenile metamorphosis. Fin differentiation began at 10–12 mm, 20–30 d posthatch, and was completed at 19–20 mm and 50–60 d, concomitant with swim bladder inflation. Metamorphosis was completed in 120 d when juveniles were about 35 mm total length. The prolonged larva fin fold stage lacking a functional swim bladder may be an adaptation to passively use water currents in estuarine nursery areas.

Early Life History of Fishes in the San Francisco Estuary and Watershed

2004 ◽  
Keyword(s):  
San Francisco ◽  
Striped Bass ◽  
Vertical Migration ◽  
Early Life ◽  
Life Histories ◽  
Early Life History ◽  
Small Surface ◽  
Delta Smelt ◽  
Larval Fishes ◽  
History Of

<em>Abstract.</em>—The goal of this study was to determine if the vertical distribution of larval delta smelt <em>Hypomesus transpacificus </em>and striped bass <em>Morone saxatilis </em>was affected by tidal stage and diel period. Delta smelt and striped bass have similar early life histories in that their larvae drift downstream from freshwater spawning habitats to brackish water rearing habitats. Little is known on whether the larvae undergo a vertical migration as they move downstream. Conical plankton nets were used to collect larval fishes from the surface, middle, and bottom sections of the main channels of the Sacramento and San Joaquin rivers. Samples were collected over six paired day–night cruises. Approximately 45,000 fish were collected; 82% were striped bass and 2% were delta smelt. More delta smelt were caught at night than during the day, and more at middle depth than surface or bottom. Very few striped bass were found at surface during day; most were caught at middle depth. Both species were fairly dispersed throughout the water column at night. Although striped bass larvae appear to undergo a small surface to middepth migration, this study indicates that larval delta smelt and striped bass do not undergo a mass diel or tidal vertical migration as they drift down the Sacramento and San Joaquin rivers.

Early Life History of Fishes in the San Francisco Estuary and Watershed

2004 ◽  
Keyword(s):  
Life History ◽  
San Francisco ◽  
Striped Bass ◽  
Early Life ◽  
Early Life History ◽  
San Francisco Estuary ◽  
Delta Smelt ◽  
History Of ◽  
Acanthogobius Flavimanus ◽  
Longfin Smelt

<em>Abstract.</em>—We analyzed data on spring and summertime larval and juvenile fish distribution and abundance in the upper San Francisco Estuary (SFE), California between 1995 and 2001. The upper SFE includes the tidal freshwater areas of the Sacramento–San Joaquin Delta downstream to the euryhaline environment of San Pablo Bay. The sampling period included years with a variety of outflow conditions. Fifty taxa were collected using a larval tow net. Two common native species, delta smelt <em>Hypomesus transpacificus </em>and longfin smelt <em>Spirinchus thaleichthys</em>, and four common alien taxa, striped bass <em>Morone saxatilis</em>, threadfin shad <em>Dorosoma petenense</em>, gobies of the genus <em>Tridentiger</em>, and yellowfin goby <em>Acanthogobius flavimanus</em>, were selected for detailed analysis. Outflow conditions had a strong influence on the geographic distribution of most of the species, but distribution with respect to the 2 psu isohaline (X2) was not affected. The distribution patterns of delta smelt, longfin smelt, and striped bass were consistent with larvae moving from upstream freshwater spawning areas to downstream estuarine rearing areas. There were no obvious relationships of outflow with annual abundance indices. Our results support the idea of using X2 as an organizing principle in understanding the ecology of larval fishes in the upper SFE. Additional years of sampling will likely lead to additional insights into the early life history of upper SFE fishes.

Achieving pregnancy at a late reproductive age in a patient with a history of multiple failed in vitro fertilization attempts

2021 ◽  
Vol 7_2021 ◽  
pp. 202-209
Author(s):  
Kirienko K.V. Kirienko ◽  
Osina E.A. Osina ◽  
Apryshko V.P. Apryshko ◽  
Voloshanenko V.V. Voloshanenko V ◽  
Yakovenko S.A. Yakovenko S ◽  
...  
Keyword(s):  
In Vitro Fertilization ◽  
Reproductive Age ◽  
Vitro Fertilization ◽  
History Of

Ovarian hyperstimulation and the in vitro fertilization procedure do not influence early neuromotor development; a history of subfertility does

2010 ◽  
Vol 93 (2) ◽  
pp. 544-553 ◽  
Author(s):  
Karin J. Middelburg ◽  
Maaike L. Haadsma ◽  
Maas Jan Heineman ◽  
Arend F. Bos ◽  
Mijna Hadders-Algra
Keyword(s):  
In Vitro Fertilization ◽  
Ovarian Hyperstimulation ◽  
Vitro Fertilization ◽  
History Of ◽  
Neuromotor Development

Early Life History of Fishes in the San Francisco Estuary and Watershed

2004 ◽  
Keyword(s):  
San Francisco ◽  
Open Water ◽  
Early Life History ◽  
Spatial And Temporal Variability ◽  
Larval Rearing ◽  
Restored Wetlands ◽  
Marsh Edge ◽  
Reference Marsh ◽  
History Of ◽  
Native Fishes

<em>Abstract.</em>—We examined the spatial and temporal variability of native and alien ichthyoplankton in three habitat types (marsh edge, shallow open-water, and river channel) in one reference and three restored marshes in the Sacramento–San Joaquin Delta, California, during 1998 and 1999. More than 6,700 fish embryos and 25,000 larvae represented by 10 families were collected in 240 tows during the 2-year study. Overall, the assemblage was dominated by alien fishes, but natives were more abundant during winter and spring, whereas aliens were more abundant during summer. Overall abundance was highest in marsh edge habitats, suggesting that this habitat provides favorable larval rearing habitats for many fishes. The reference marsh was dominated by alien species making it difficult to assess whether it had attributes that promoted use by native fish. Ichthyoplankton abundance varied comparably at restored sites of similar configuration. The restored site, with minimal tidal exchange and greater lower trophic productivity, supported the highest densities of alien fish. We conclude that restoration projects in this region of the estuary must consider the potential impacts of alien fishes on natives and evaluate strategies designed to improve recruitment success of native fishes. Specifically, we suggest that restored wetlands that offer only winter and spring inundation periods may provide maximum benefits to natives while limiting access by many alien fishes regardless of specific habitat-use requirements.

Early Life History of Fishes in the San Francisco Estuary and Watershed

2004 ◽  
Keyword(s):  
Growth Rate ◽  
San Francisco ◽  
Striped Bass ◽  
Growth Rates ◽  
Early Life History ◽  
San Francisco Estuary ◽  
Annual Growth ◽  
Factors Affecting ◽  
Juvenile Abundance ◽  
History Of

<em>Abstract.</em>—We investigated factors affecting growth of larval striped bass <em>Morone saxatilis </em>in the San Francisco Estuary from 1984 to 1993. We estimated ages and growth rates of larval striped bass from daily otolith increments. Mean annual growth rates of 6–14 mm standard length striped bass varied from 0.13 to 0.27mm/d, the lowest rate occurring in 1989 and the highest in 1992. The 1989 growth rate was significantly lower than all other years, and growth rates for 1992 and 1993 were significantly higher than all other years, but did not differ from one another. Differences in annual growth rates apparently were due mainly to differences in mean annual prey densities because growth rate increased as prey density increased. Compared to both laboratory measured growth rates and growth rates of field-caught Chesapeake Bay larvae, growth rates from the San Francisco Estuary appeared to be high for the food available, indicating that larvae can grow at relatively high rates even at low prey densities. Correlation analyses did not support density-dependent control of growth rates. Growth rate was not significantly related to mean annual conductivity, water temperature, mortality rates, or the juvenile abundance index, but was significantly and positively correlated with densities of 1-mm length-groups of 9–14-mm striped bass.

A ROLE FOR CONJOINT ANALYSIS IN TECHNOLOGY ASSESSMENT IN HEALTH CARE?

1999 ◽  
Vol 15 (3) ◽  
pp. 443-457 ◽  
Author(s):  
Mandy Ryan
Keyword(s):  
Health Care ◽  
Conjoint Analysis ◽  
Technology Assessment ◽  
Assessment Instruments ◽  
Relative Importance ◽  
Services Research ◽  
Vitro Fertilization ◽  
Trade Offs ◽  
History Of

The aim of this paper is to demonstrate the use of conjoint analysis (CA) in health services research. Conjoint analysis is first explained, with emphasis on the history of the technique, followed by an explanation of how to carry out such a study and how the results from such a study can be used. The technique is demonstrated with reference to a study that looks at the benefits of in vitro fertilization. It is shown how CA can be used to estimate the relative importance of attributes, the trade-offs individuals make between these attributes, willingness to pay if cost is included as an attribute, and utility or benefit scores for different ways of providing a service. The paper then considers the potential advantages of CA over other, more commonly used benefit assessment instruments. Finally, there is discussion of the issues raised in the design and analysis of CA studies. It is concluded that these issues must be addressed before the technique becomes an established instrument for technology assessment.

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