Calculation of biomass trend, exploitation rate, and surplus production from survey and catch data

2001 ◽  
Vol 58 (3) ◽  
pp. 579-584 ◽  
Author(s):  
Ray Hilborn
Keyword(s):  
United States ◽  
Survey Data ◽  
Eastern United States ◽  
Stock Size ◽  
Surplus Production ◽  
Catch Data ◽  
Exploitation Rate ◽  
Alternative Hypotheses ◽  
History Of

If survey data and historical catches are available, it is possible to estimate the history of surplus production from a fishery as long as the scalar between the survey and absolute biomass can be estimated. Alternative hypotheses about present stock size correspond to alternative hypotheses about the scalar, so that by specifying an estimate of the current stock size or exploitation rate, the entire trend of surplus production can be calculated. An example, using monkfish (Lophius americanus) in the eastern United States, is given that shows quite robust conclusions to alternative assumptions about current stock size, and the analysis suggests that the surplus production from monkfish has been the highest during the period of lowest stock size.

scholarly journals The 2009 Late Blight Pandemic in the Eastern United States – Causes and Results

Plant Disease ◽  
2013 ◽  
Vol 97 (3) ◽  
pp. 296-306 ◽  
Author(s):  
W. E. Fry ◽  
M. T. McGrath ◽  
A. Seaman ◽  
T. A. Zitter ◽  
A. McLeod ◽  
...  
Keyword(s):  
United States ◽  
Late Blight ◽  
Phytophthora Infestans ◽  
Current Situation ◽  
Causal Agent ◽  
Community Supported Agriculture ◽  
Eastern United States ◽  
Tomato Crop ◽  
History Of ◽  
Mainstream Press

The tomato late blight pandemic of 2009 made late blight into a household term in much of the eastern United States. Many home gardeners and many organic producers lost most if not all of their tomato crop, and their experiences were reported in the mainstream press. Some CSAs (Community Supported Agriculture) could not provide tomatoes to their members. In response, many questions emerged: How did it happen? What was unusual about this event compared to previous late blight epidemics? What is the current situation in 2012 and what can be done? It's easiest to answer these questions, and to understand the recent epidemics of late blight, if one knows a bit of the history of the disease and the biology of the causal agent, Phytophthora infestans.

scholarly journals Exploring the Concept of Lineage Diversity across North American Forests

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 520 ◽  
Author(s):  
Kyle G. Dexter ◽  
Ricardo A. Segovia ◽  
Andy R. Griffiths
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
North American ◽  
Conservation Priorities ◽  
Equal Weight ◽  
Eastern United States ◽  
Genetic Lineages ◽  
Southern Rocky Mountains ◽  
History Of ◽  
Lineage Diversity

Lineage diversity can refer to the number of genetic lineages within species or to the number of deeper evolutionary lineages, such as genera or families, within a community or assemblage of species. Here, we study the latter, which we refer to as assemblage lineage diversity (ALD), focusing in particular on its richness dimension. ALD is of interest to ecologists, evolutionary biologists, biogeographers, and those setting conservation priorities, but despite its relevance, it is not clear how to best quantify it. With North American tree assemblages as an example, we explore and compare different metrics that can quantify ALD. We show that both taxonomic measures (e.g., family richness) and Faith’s phylogenetic diversity (PD) are strongly correlated with the number of lineages in recent evolutionary time, but have weaker correlations with the number of lineages deeper in the evolutionary history of an assemblage. We develop a new metric, time integrated lineage diversity (TILD), which serves as a useful complement to PD, by giving equal weight to old and recent lineage diversity. In mapping different ALD metrics across the contiguous United States, both PD and TILD reveal high ALD across large areas of the eastern United States, but TILD gives greater value to the southeast Coastal Plain, southern Rocky Mountains and Pacific Northwest, while PD gives relatively greater value to the southern Appalachians and Midwest. Our results demonstrate the value of using multiple metrics to quantify ALD, in order to highlight areas of both recent and older evolutionary diversity.

A performance evaluation of surplus production models with time-varying intrinsic growth in dynamic ecosystems

2019 ◽  
Vol 76 (12) ◽  
pp. 2245-2255 ◽  
Author(s):  
Geneviève M. Nesslage ◽  
Michael J. Wilberg
Keyword(s):  
Growth Rate ◽  
Time Series ◽  
Survey Data ◽  
Atlantic Menhaden ◽  
Data Sets ◽  
Time Varying ◽  
Intrinsic Growth Rate ◽  
Surplus Production ◽  
Production Models ◽  
Exploitation Rate

We conducted a simulation study to evaluate performance of surplus production models (SPMs) with a time-varying intrinsic growth rate (SPMTVr) for stocks with predation-driven changes in productivity. Data sets were simulated using an age-structured, linked, predator–prey model of Atlantic menhaden (Brevoortia tyrannus), a forage fish native to the Northwest Atlantic, and Atlantic striped bass (Morone saxatilis), its primary predator, with differing time series of fishing mortality on both predator and prey. Simulations generated test data sets for Atlantic menhaden SPMs that included either a static or time-varying intrinsic growth rate parameter. The SPMTVr largely produced more accurate, less variable estimates of exploitation rate and biomass than models with static intrinsic growth. We also applied SPMTVr to empirical Atlantic menhaden catch and survey data for 1964–2016. The SPMTVr fit the survey data well, estimated an intrinsic growth rate time series that mirrored long-term juvenile survey trends, and produced biomass and exploitation rate trends that mirrored a statistical catch-at-age model. The SPMTVr estimated dynamic, maximum sustainable yield (MSY)-based reference points that reflected changing stock productivity.

scholarly journals Alveolar echinococcosis in a dog in the eastern United States

2020 ◽  
Vol 32 (5) ◽  
pp. 742-746
Author(s):  
Anne Zajac ◽  
Donald Fairman ◽  
Evan McGee ◽  
Bridgette Wells ◽  
Andrew Peregrine ◽  
...  
Keyword(s):  
United States ◽  
Alveolar Echinococcosis ◽  
Sequence Data ◽  
Small Animal ◽  
The United States ◽  
Eastern United States ◽  
Fine Needle Aspirates ◽  
Pcr Product ◽  
History Of ◽  
Histopathologic Findings

An 8-y-old Labrador Retriever was presented to a small animal practice in northern Virginia with a history of recent lethargy. Physical examination findings were unremarkable. Ultrasound revealed several large hepatic masses and multiple smaller masses involving the pancreas. Cytologic findings on fine-needle aspirates of the hepatic masses included inflammation and necrosis with eosinophilic, membranous oval structures consistent with cestode infection. Histopathologic findings for biopsies of these masses included extensive necrosis, inflammation, and PAS-positive hyaline-like membranous material interpreted as metacestode cyst wall. A PCR product was generated from aspirate material using primers specific for Echinococcus multilocularis. Subsequent sequence data were 100% homologous to E. multilocularis NADH dehydrogenase subunit I gene sequences. The dog received daily oral albendazole (10 mg/kg) treatment, but its condition deteriorated, and the dog was euthanized. The dog, born in Mississippi, was brought as a puppy to Virginia with no other travel history. To our knowledge, alveolar echinococcosis has not been reported previously in a dog in the United States; E. multilocularis infection was apparently acquired in the mid-Atlantic region of the United States.

The Paths of the Trade: Italian Stonemasons in the United States

1986 ◽  
Vol 20 (4) ◽  
pp. 779-795
Author(s):  
Patrizia Audenino
Keyword(s):  
United States ◽  
Social Networks ◽  
Trade Union ◽  
The United States ◽  
Close Connection ◽  
Eastern United States ◽  
Temporary Emigration ◽  
History Of ◽  
Insight Into

This article examines the history of Italian stonecutters from Valle Cervo, an alpine village in Piedmont, Italy. These migrants comprised a wave of temporary emigration to the United States between 1870 and 1915. The migration paths followed by these artisans demonstrates the close connection among their various migrations, settlements and opportunities for employment in the eastern United States. The reconstruction of the histories of individual emigrants, utilizing Italian and American sources, census records, trade-union press and private documents, provides some insight into the experiences of these stonecutters and their social networks.

Sourcing Busycon Artifacts of the Eastern United States

1993 ◽  
Vol 58 (2) ◽  
pp. 333-347 ◽  
Author(s):  
Cheryl Claassen ◽  
Samuella Sigmann
Keyword(s):  
United States ◽  
Body Part ◽  
Atlantic Water ◽  
Eastern United States ◽  
Elemental Ratios ◽  
Tropical Water ◽  
Busycon Carica ◽  
History Of ◽  
Shell Chemical ◽  
Monks Mound

A review of the history of marine-shell chemical-sourcing efforts preceeds the introduction of this project. Atomic-absorption spectroscopy (AAS) was used to assay levels of Ca, Mg, Fe, and Sr, in 44 prehistoric Busycon carica and Busycon perversum specimens from the eastern United States. Control shells (35) were collected from food refuse in coastal archaeological sites from Long Island to the Mexico—United States border. Subject shells came from nine Archaic and Mississippian sites. Elemental ratios were clustered to derive a probable water-body origin for the nine artifacts. The influence of diagenesis, body part, and species was negligible, but geography heavily influenced the results. The three shells from Monks Mound indicated origin in tropical, eastern Gulf, and Atlantic water. The shells from the Indian Knoll, Mulberry, and Tatham sites appear to have originated in eastern Gulf waters. The shell from the Archaic-period Ward site seems to have come from tropical water.

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