scholarly journals Assessment of Reintroduction of American Eel into Buffalo Creek (Susquehanna River, Pennsylvania)

Author(s):  
Joshua J. Newhard ◽  
Julie Devers ◽  
Steve Minkkinen ◽  
Mike Mangold

Abstract American Eel Anguilla rostrata populations along the Atlantic coast of the United States have been in decline over the past several decades. One suggested cause of the decline is construction of barriers that block access to upstream tributaries where they can spend a significant portion of their lives. Success of reintroduction efforts above barriers has rarely been evaluated. Within the Susquehanna River (Chesapeake Bay watershed), over 1 million eels were released above four major downstream barriers in the past decade. We used backpack electrofishing and tagging to monitor growth, sexual differentiation, and population density of reintroduced eels in Buffalo Creek, a tributary to the Susquehanna River (Pennsylvania). From 2012 to 2019, we caught over 2,000 individuals, tagged more than 1,800, and recaptured 229. Recaptured eels provided insight into growth, sexual differentiation, and movement. Nearly 99% of recaptures remained near stocking locations. The average growth rate was 47.8 mm/y and ranged between −5.8 and 116.0 mm/y. Females generally grew significantly faster than males, and growth rates of several females exceeded 100 mm/y, a rate typically associated with estuarine residents. The population density within stocking sites was over 2,300 eels/km, roughly four times higher than Susquehanna River tributaries below the most downstream dam, and exceeded the target stocking goal of 529 eels/km. While we caught most eels in areas sampled near stocking locations, we captured some eels in smaller upstream tributaries away from stocking locations. Our study is the first to examine how reintroduced eels grow following stocking above four major dams on the Susquehanna River. We suggest that managers considering moving eels above blockages account for release location and density to achieve desired benefits to the overall population.

Geology ◽  
2019 ◽  
Vol 47 (12) ◽  
pp. 1151-1155 ◽  
Author(s):  
Nathalie W. Schieder ◽  
Matthew L. Kirwan

Abstract Ghost forests, consisting of dead trees adjacent to marshes, are a striking feature of low-lying coastal and estuarine landscapes, and they represent the migration of coastal ecosystems with relative sea-level rise (RSLR). Although ghost forests have been observed along many coastal margins, rates of ecosystem change and their dependence on RSLR remain poorly constrained. Here, we reconstructed forest retreat rates using sediment coring and historical imagery at five sites along the Mid-Atlantic coast of the United States, a hotspot for accelerated RSLR. We found that the elevation of the marsh-forest boundary generally increased with RSLR over the past 2000 yr, and that retreat accelerated concurrently with the late 19th century acceleration in global sea level. Lateral retreat rates increased through time for most sampling intervals over the past 150 yr, and modern lateral retreat rates are 2 to 14 times faster than pre-industrial rates at all sites. Substantial deviations between RSLR and forest response are consistent with previous observations that episodic disturbance facilitates the mortality of adult trees. Nevertheless, our work suggests that RSLR is the primary determinant of coastal forest extent, and that ghost forests represent a direct and prominent visual indicator of climate change.


1911 ◽  
Vol 5 (1) ◽  
pp. 1-31 ◽  
Author(s):  
Robert Lansing

The Arbitral Tribunal of the Permanent Court at The Hague, by its award of the 7th of last September, in the case of the North Atlantic Coast Fisheries, brought to a close a controversy which in its various phases has been an almost constant source of vexatious dispute between the United States and Great Britain for the past seventy years.A treaty, granting exceptional rights, such as that which this Tribunal was called upon to consider, is peculiarly susceptible to different interpretations as the course of time brings new conditions not contemplated by its negotiators. The relations of the parties are changed. A liberty which at the date of the treaty was considered indispensable may become worthless, while one which was deemed insignificant may in years assume a place of vital importance to the beneficiaries under the grant. This change of conditions and of the value of rights has been especially true of the liberties acquired by the United States for its inhabitants under the first article of the Treaty of October 20, 1818.


2016 ◽  
Vol 58 (1) ◽  
pp. 159-180 ◽  
Author(s):  
Wyatt MacGaffey

AbstractThe past thirty years have seen, particularly in the United States, a transformation in the public image of “Kongo,” an ill-defined entity (a tribe, a kingdom, a culture, a region?) on the Atlantic coast of Central Africa. The efforts of R. F. Thompson, professor of art history at Yale, and A. Fu-kiau, himself Kongolese, have done much to popularize a “Kongo” characterized more by its romantic appeal than by historical or ethnographic verisimilitude. Elsewhere in the Americas, the reputation of “Kongo” has suffered by comparison with “Yoruba,” another historically emergent Atlantic identity, based in West Africa. These identities, and the supposed contrast between them, are products of an increasingly complex trans-Atlantic discourse.


Author(s):  
Ella Inglebret ◽  
Amy Skinder-Meredith ◽  
Shana Bailey ◽  
Carla Jones ◽  
Ashley France

The authors in this article first identify the extent to which research articles published in three American Speech-Language-Hearing Association (ASHA) journals included participants, age birth to 18 years, from international backgrounds (i.e., residence outside of the United States), and go on to describe associated publication patterns over the past 12 years. These patterns then provide a context for examining variation in the conceptualization of ethnicity on an international scale. Further, the authors examine terminology and categories used by 11 countries where research participants resided. Each country uses a unique classification system. Thus, it can be expected that descriptions of the ethnic characteristics of international participants involved in research published in ASHA journal articles will widely vary.


Crisis ◽  
2020 ◽  
pp. 1-5
Author(s):  
Shannon Lange ◽  
Courtney Bagge ◽  
Charlotte Probst ◽  
Jürgen Rehm

Abstract. Background: In recent years, the rate of death by suicide has been increasing disproportionately among females and young adults in the United States. Presumably this trend has been mirrored by the proportion of individuals with suicidal ideation who attempted suicide. Aim: We aimed to investigate whether the proportion of individuals in the United States with suicidal ideation who attempted suicide differed by age and/or sex, and whether this proportion has increased over time. Method: Individual-level data from the National Survey on Drug Use and Health (NSDUH), 2008–2017, were used to estimate the year-, age category-, and sex-specific proportion of individuals with past-year suicidal ideation who attempted suicide. We then determined whether this proportion differed by age category, sex, and across years using random-effects meta-regression. Overall, age category- and sex-specific proportions across survey years were estimated using random-effects meta-analyses. Results: Although the proportion was found to be significantly higher among females and those aged 18–25 years, it had not significantly increased over the past 10 years. Limitations: Data were self-reported and restricted to past-year suicidal ideation and suicide attempts. Conclusion: The increase in the death by suicide rate in the United States over the past 10 years was not mirrored by the proportion of individuals with past-year suicidal ideation who attempted suicide during this period.


2013 ◽  
Vol 10 (2) ◽  
pp. 115-124
Author(s):  
Philip L. Martin

Japan and the United States, the world’s largest economies for most of the past half century, have very different immigration policies. Japan is the G7 economy most closed to immigrants, while the United States is the large economy most open to immigrants. Both Japan and the United States are debating how immigrants are and can con-tribute to the competitiveness of their economies in the 21st centuries. The papers in this special issue review the employment of and impacts of immigrants in some of the key sectors of the Japanese and US economies, including agriculture, health care, science and engineering, and construction and manufacturing. For example, in Japanese agriculture migrant trainees are a fixed cost to farmers during the three years they are in Japan, while US farmers who hire mostly unauthorized migrants hire and lay off workers as needed, making labour a variable cost.


Author(s):  
Pierre Rosanvallon

It's a commonplace occurrence that citizens in Western democracies are disaffected with their political leaders and traditional democratic institutions. But this book argues that this crisis of confidence is partly a crisis of understanding. The book makes the case that the sources of democratic legitimacy have shifted and multiplied over the past thirty years and that we need to comprehend and make better use of these new sources of legitimacy in order to strengthen our political self-belief and commitment to democracy. Drawing on examples from France and the United States, the book notes that there has been a major expansion of independent commissions, NGOs, regulatory authorities, and watchdogs in recent decades. At the same time, constitutional courts have become more willing and able to challenge legislatures. These institutional developments, which serve the democratic values of impartiality and reflexivity, have been accompanied by a new attentiveness to what the book calls the value of proximity, as governing structures have sought to find new spaces for minorities, the particular, and the local. To improve our democracies, we need to use these new sources of legitimacy more effectively and we need to incorporate them into our accounts of democratic government. This book is an original contribution to the vigorous international debate about democratic authority and legitimacy.


2014 ◽  
Vol 9 (3) ◽  
pp. 201-213
Author(s):  
Renata Marks-Bielska ◽  
Wiesława Lizińska ◽  
Izabela Serocka

Evaluation of the importance of the USA as the trade partner of Poland is the main objective of the paper, based on the changes in the value of trade during the years 2000-2012 and changes in the structure of trade during the years 2008-2012. The data from the Statistical Yearbooks of Foreign Trade published by the Central Statistical Office was used. The potential for foreign trade growth was illustrated using the simplified analysis based on the gravity model of foreign trade concept. Gradually increasing value of Polish trade with the USA (the average growth rate 9.8%, EU-15 countries 13.1%). Polish exports are characterised by a higher than imports growth rate (USA - exports growth by 12.5%, imports 9.2%, EU-15 - exports 15.1%, imports 11.6%). Trade is strongly dominated by position of one group of products (over 30% share in both exports and imports). The potential of trade is poorly exploited currently. Trade was focused mainly on the countries situated in the close neighbourhood (mainly the EU countries with the domination of Germany).


2009 ◽  
Vol 1 (1) ◽  
pp. 93-116 ◽  
Author(s):  
Mauricio Tenorio-Trillo

By identifying two general issues in recent history textbook controversies worldwide (oblivion and inclusion), this article examines understandings of the United States in Mexico's history textbooks (especially those of 1992) as a means to test the limits of historical imagining between U. S. and Mexican historiographies. Drawing lessons from recent European and Indian historiographical debates, the article argues that many of the historical clashes between the nationalist historiographies of Mexico and the United States could be taught as series of unsolved enigmas, ironies, and contradictions in the midst of a central enigma: the persistence of two nationalist historiographies incapable of contemplating their common ground. The article maintains that lo mexicano has been a constant part of the past and present of the US, and lo gringo an intrinsic component of Mexico's history. The di erences in their historical tracks have been made into monumental ontological oppositions, which are in fact two tracks—often overlapping—of the same and shared con ictual and complex experience.


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