Low recruitment, high tissue loss, and juvenile mortality limit recovery of kelp following large-scale defoliation

Juvenile mortality is an important factor affecting the spatiotemporal dynamics of fish recruitment, but estimation of the spatiotemporal variations in juvenile mortality rates remains challenging. We developed a state-space metapopulation dynamics model to simultaneously estimate spatiotemporal variations in juvenile mortality rates and cohort strength and applied this general modelling framework to data from multiple surveys for juvenile (ages 2–5) Atlantic cod (Gadus morhua) stocks off Newfoundland and Labrador (NL). We found large-scale synchronized dynamics of decreasing juvenile mortality rates and increasing cohort strength from offshore surveys off eastern and southeastern NL, suggesting improving reproduction and survival rates for juvenile cod. No synchronized patterns of juvenile mortality rates and cohort strength were detected for cod stocks off southern and western NL, indicating more complex cod population spatial structures in those areas. Our study demonstrates the potential of juvenile mortality to cause temporally variable and spatially synchronized dynamics of fish recruitment, and the spatial patterns of juvenile mortality and cohort strength indicate some potential mismatch between cod population structure and current management units off NL.

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Failure to respond to a coral disease outbreak: Potential costs and consequences

10.7287/peerj.preprints.27860 ◽

2019 ◽

Author(s):

William F Precht

Keyword(s):

Repeated Measures ◽

Large Scale ◽

Coral Disease ◽

Genetic Material ◽

Monitoring Program ◽

Initial Response ◽

Disease Outbreak ◽

Tissue Loss ◽

Coral Tissue ◽

Resource Managers

A coral disease with white plague-like signs was observed near Virginia Key, Florida, in September 2014. The disease outbreak directly followed a regional high temperature coral-bleaching event. Now called stony coral tissue loss disease (SCTLD), it has spread the length of the Florida Reef Tract from Key West to Martin County, a distance of about 450 km. Recently, the disease has also been observed at a number of sites throughout the Caribbean. The high prevalence of disease, the number of susceptible species, and the high mortality of corals affected suggests this outbreak is arguably one of the most lethal ever recorded. The initial response to this catastrophic disease by resource mangers with purview over the ecosystem was slow. There is generally a very short window of opportunity to intervene in disease amelioration or eradication in the marine environment. This slow response enabled the disease to spread unchecked. Why was the response to the loss of our coral reefs to a coral disease epidemic, such a massive failure? This includes our failure as scientists, regulators, resource managers, the local media, and policy makers alike. This review encapsulates the numerous reasons for our failures during the first few years of the outbreak. Specifically, I show how the Port Miami dredging project that was ongoing at the time of the initial outbreak created a distraction as local NGO's, regulatory agencies, and resource managers initially blamed the project for observed large-scale coral losses. However, detailed analysis of 650 tagged corals that were part of a repeated measures monitoring program required for permit compliance associated with the Port Miami dredge project reveal that both disease susceptibility and coral mortality are invariant with the results collected by a number of scientific teams throughout the region. Finally, when the agencies responded to the outbreak the effort it was too little and much too late to make a meaningful difference. Because of the languid management response to this outbreak, we are now sadly faced with a situation where much of our management efforts are focused on the rescue of genetic material from coral species now at risk of regional extinction.

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Failure to respond to a coral disease outbreak: Potential costs and consequences

10.7287/peerj.preprints.27860v1 ◽

2019 ◽

Author(s):

William F Precht

Keyword(s):

Repeated Measures ◽

Large Scale ◽

Coral Disease ◽

Genetic Material ◽

Monitoring Program ◽

Initial Response ◽

Disease Outbreak ◽

Tissue Loss ◽

Coral Tissue ◽

Resource Managers

A coral disease with white-plague like signs was observed near Virginia Key, Florida, in September 2014. The disease outbreak directly followed a regional high temperature coral-bleaching event. Now called stony coral tissue loss disease (SCTLD), it has spread the length of the Florida Reef Tract from Key West to Martin County, a distance of about 450 km. Recently, the disease has also been observed at a number of sites throughout the Caribbean. The high prevalence of disease, the number of susceptible species, and the high mortality of corals affected suggests this outbreak is arguably one of the most lethal ever recorded. The initial response to this catastrophic disease by resource mangers with purview over the ecosystem was slow. There is generally a very short window of opportunity to intervene in disease amelioration or eradication in the marine environment. This slow response enabled the disease to spread unchecked. Why was the response to the loss of our coral reefs to a coral disease epidemic, such a massive failure? This includes our failure as scientists, regulators, resource managers, the local media, and policy makers alike. This review encapsulates the numerous reasons for our failures during the first few years of the outbreak. Specifically, I show how the Port Miami dredging project that was ongoing at the time of the initial outbreak created a distraction as local NGO's, regulatory agencies, and resource managers initially blamed the project for observed large-scale coral losses. However, detailed analysis of 650 tagged corals that were part of a repeated measures monitoring program required for permit compliance associated with the Port Miami dredge project reveal that both disease susceptibility and coral mortality are invariant with the results collected by a number of scientific teams throughout the region. Finally, when the agencies responded to the outbreak the effort it was too little and much too late to make a meaningful difference. Because of the languid management response to this outbreak, we are now sadly faced with a situation where much of our management efforts are focused on the rescue of genetic material from coral species now at risk of regional extinction.

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Short- and Long-Term Effectiveness of Coral Disease Treatments

Frontiers in Marine Science ◽

10.3389/fmars.2021.675349 ◽

2021 ◽

Vol 8 ◽

Author(s):

Karen L. Neely ◽

Colin P. Shea ◽

Kevin A. Macaulay ◽

Emily K. Hower ◽

Michelle A. Dobler

Keyword(s):

Large Scale ◽

Coral Disease ◽

Treatment Strategies ◽

Tissue Loss ◽

Coral Tissue ◽

Logistic Regression Models ◽

Reef Tract ◽

Short And Long Term

Since 2014, stony coral tissue loss disease (SCTLD) has led to large-scale mortality of over 20 coral species throughout the Florida Reef Tract. In 2019, in-water disease intervention strategies were implemented to treat affected corals. Two treatment strategies were employed: (1) topical application of an amoxicillin paste directly to disease margins, and (2) application of a chlorinated epoxy to disease margins as well as an adjacent “disease break” trench. Effectiveness of treatments on 2,379 lesions from 725 corals representing five species was evaluated using mixed effects logistic regression models which demonstrated substantially greater effectiveness of amoxicillin compared to chlorine-treated lesions across all species up to 3 months post-treatment. As a result of the failed chlorinated epoxy treatments, any new lesions that appeared during subsequent monitoring events were treated with amoxicillin paste, and all corals were monitored and treated as needed approximately every 2 months for up to 24 months. The health status of 1664 amoxicillin-treated corals during each monitoring event was used to model the probability of a coral being uninfected over time. Models included species and geographic regions as variables. The appearance of new lesions (reinfection rates) varied by species, and offshore sites showed greater reinfection rates than inshore sites; however, all sites and species exhibited a decreased probability of reinfection with time since initial treatment. We conclude that topical amoxicillin treatments are highly effective at halting SCTLD lesions and that through initial and follow-up treatments as needed, colonies and reef sites will progress toward a lower prevalence of SCTLD.

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Failure to respond to a coral disease outbreak: Potential costs and consequences

10.7287/peerj.preprints.27860v2 ◽

2019 ◽

Cited By ~ 2

Author(s):

William F Precht

Keyword(s):

Repeated Measures ◽

Large Scale ◽

Coral Disease ◽

Genetic Material ◽

Monitoring Program ◽

Initial Response ◽

Disease Outbreak ◽

Tissue Loss ◽

Coral Tissue ◽

Resource Managers

A coral disease with white plague-like signs was observed near Virginia Key, Florida, in September 2014. The disease outbreak directly followed a regional high temperature coral-bleaching event. Now called stony coral tissue loss disease (SCTLD), it has spread the length of the Florida Reef Tract from Key West to Martin County, a distance of about 450 km. Recently, the disease has also been observed at a number of sites throughout the Caribbean. The high prevalence of disease, the number of susceptible species, and the high mortality of corals affected suggests this outbreak is arguably one of the most lethal ever recorded. The initial response to this catastrophic disease by resource mangers with purview over the ecosystem was slow. There is generally a very short window of opportunity to intervene in disease amelioration or eradication in the marine environment. This slow response enabled the disease to spread unchecked. Why was the response to the loss of our coral reefs to a coral disease epidemic, such a massive failure? This includes our failure as scientists, regulators, resource managers, the local media, and policy makers alike. This review encapsulates the numerous reasons for our failures during the first few years of the outbreak. Specifically, I show how the Port Miami dredging project that was ongoing at the time of the initial outbreak created a distraction as local NGO's, regulatory agencies, and resource managers initially blamed the project for observed large-scale coral losses. However, detailed analysis of 650 tagged corals that were part of a repeated measures monitoring program required for permit compliance associated with the Port Miami dredge project reveal that both disease susceptibility and coral mortality are invariant with the results collected by a number of scientific teams throughout the region. Finally, when the agencies responded to the outbreak the effort it was too little and much too late to make a meaningful difference. Because of the languid management response to this outbreak, we are now sadly faced with a situation where much of our management efforts are focused on the rescue of genetic material from coral species now at risk of regional extinction.

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Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1

International Astronomical Union Colloquium ◽

10.1017/s0252921100031493 ◽

1999 ◽

Vol 173 ◽

pp. 243-248

Author(s):

D. Kubáček ◽

A. Galád ◽

A. Pravda

Keyword(s):

Image Processing ◽

Large Scale ◽

Harvard College ◽

Oak Ridge ◽

Large Scale Structures ◽

Short Period Comet ◽

Short Period ◽

Scale Structures ◽

Harvard College Observatory ◽

Period Comet

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

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Evolution of Large-Scale Coronal Structures

International Astronomical Union Colloquium ◽

10.1017/s0252921100024945 ◽

1994 ◽

Vol 144 ◽

pp. 29-33

Author(s):

P. Ambrož

Keyword(s):

Magnetic Field ◽

Field Line ◽

Large Scale ◽

Coronal Magnetic Field ◽

Source Surface ◽

Solar Cycles ◽

Characteristic Relationship ◽

The Magnetic Field ◽

Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

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Large-scale Motion of Solar Filaments

International Astronomical Union Colloquium ◽

10.1017/s0252921100064502 ◽

2000 ◽

Vol 179 ◽

pp. 205-208

Author(s):

Pavel Ambrož ◽

Alfred Schroll

Keyword(s):

Magnetic Flux ◽

Proper Motion ◽

Time Scale ◽

Large Scale ◽

Accuracy Of Measurements ◽

Solar Filaments ◽

General Movement ◽

Scale Motion ◽

Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

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Some applications of electron beam microanalysis techniques in VLSI process evaluation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007463x ◽

1983 ◽

Vol 41 ◽

pp. 160-161

Author(s):

Simon Thomas

Keyword(s):

Integrated Circuits ◽

Process Evaluation ◽

Large Scale ◽

Technology Development ◽

Analytical Techniques ◽

Successful Implementation ◽

Analysis Of Failures ◽

Characterization Of Materials ◽

Circuits Vlsi

Trends in the technology development of very large scale integrated circuits (VLSI) have been in the direction of higher density of components with smaller dimensions. The scaling down of device dimensions has been not only laterally but also in depth. Such efforts in miniaturization bring with them new developments in materials and processing. Successful implementation of these efforts is, to a large extent, dependent on the proper understanding of the material properties, process technologies and reliability issues, through adequate analytical studies. The analytical instrumentation technology has, fortunately, kept pace with the basic requirements of devices with lateral dimensions in the micron/ submicron range and depths of the order of nonometers. Often, newer analytical techniques have emerged or the more conventional techniques have been adapted to meet the more stringent requirements. As such, a variety of analytical techniques are available today to aid an analyst in the efforts of VLSI process evaluation. Generally such analytical efforts are divided into the characterization of materials, evaluation of processing steps and the analysis of failures.

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Electron microscopy study of reactively sputter-deposited Ti/N films on silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131449 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1362-1363

Author(s):

V. C. Kannan ◽

A. K. Singh ◽

R. B. Irwin ◽

S. Chittipeddi ◽

F. D. Nkansah ◽

...

Keyword(s):

Integrated Circuits ◽

Large Scale ◽

Hexagonal Phase ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Process Conditions ◽

Tin Films ◽

Wide Range ◽

Fcc Phase ◽

Circuits Vlsi

Titanium nitride (TiN) films have historically been used as diffusion barrier between silicon and aluminum, as an adhesion layer for tungsten deposition and as an interconnect material etc. Recently, the role of TiN films as contact barriers in very large scale silicon integrated circuits (VLSI) has been extensively studied. TiN films have resistivities on the order of 20μ Ω-cm which is much lower than that of titanium (nearly 66μ Ω-cm). Deposited TiN films show resistivities which vary from 20 to 100μ Ω-cm depending upon the type of deposition and process conditions. TiNx is known to have a NaCl type crystal structure for a wide range of compositions. Change in color from metallic luster to gold reflects the stabilization of the TiNx (FCC) phase over the close packed Ti(N) hexagonal phase. It was found that TiN (1:1) ideal composition with the FCC (NaCl-type) structure gives the best electrical property.

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