Translocation and population establishment of Schoenus scabripes (Cyperaceae)

2021 ◽  
Author(s):  
Cameron Milne ◽  
Stephen J. Trueman ◽  
Shahla Hosseini Bai ◽  
Alison Shapcott
Keyword(s):  
Population Establishment

Factors influencing initial population establishment and habitat expansion of introduced nutrias (Myocastor coypus) in South Korea

2020 ◽  
Vol 59 ◽  
pp. 101111
Author(s):  
Sungwon Hong ◽  
Ji Yoon Kim ◽  
Young-Min Kim ◽  
Yuno Do ◽  
Dong-Kyun Kim ◽  
...  
Keyword(s):  
South Korea ◽  
Initial Population ◽  
Myocastor Coypus ◽  
Factors Influencing ◽  
Population Establishment

Reduced territorial responses in dark-eyed juncos following population establishment in a climatically mild environment

2006 ◽  
Vol 71 (4) ◽  
pp. 893-899 ◽  
Author(s):  
Melissa M. Newman ◽  
Pamela J. Yeh ◽  
Trevor D. Price
Keyword(s):  
Population Establishment

An Historical Sketch of the American Population Control Movement

1974 ◽  
Vol 4 (4) ◽  
pp. 651-674 ◽  
Author(s):  
Bonnie Mass
Keyword(s):  
World War Ii ◽  
Population Control ◽  
Health Care Facilities ◽  
Historical Background ◽  
World Population ◽  
Present System ◽  
American Population ◽  
Goods And Services ◽  
Economic Exploitation ◽  
Population Establishment

This paper critically examines the fundamental premises and historical background of the American population control movement and shows how the theories of Thomas Malthus became interwoven with those of the eugenics movement during the first four decades of this century. After World War II, the concern of eugenicists with “race betterment” and with halting multiplication of the “unfit” was replaced by claims that the world was gravely menaced by a “population explosion.” This thematic shift was consistent with the economic and political aims of American financiers and industrialists after 1945, and many of them, as indicated in this paper, became leading figures of the Population Establishment. The author has proceeded with the belief that a rationally planned economy based upon collective ownership of wealth by the working class can furnish goods and services in abundance, while eradicating unemployment, starvation, and oppression. An end to economic exploitation would greatly expand health care facilities and educational opportunities, and demographic problems could be studied and solved within the context of constructing a society that served, rather than pillaged, its members. Today, the goal of intelligent planning of births, at both the family level and the collective level, is blocked by the continuing existence of capitalism. For that reason, exposition of scientific alternatives to present-day world population control plans is preceded by the urgent task of analyzing the complex interplay between those plans and the present system of exploitation and oppression. In her conclusion, the author briefly reappraises the theories of Malthus, which have consistently shaped the decisions made by the Population Establishment. Like Malthus' assertions at the dawn of the industrial era, contemporary neo-Malthusian pronouncements ultimately rest upon assumptions that economic and social irrationalities are invincible and eternal. As the author indicates, neither capitalist society nor plans of action that seek to prolong its existence can offer solutions for today's pressing problems of famine and impoverishment.

scholarly journals A multi-year assessment of blacklegged tick (Ixodes scapularis) population establishment and Lyme disease risk areas in Ottawa, Canada, 2017-2019

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246484
Author(s):  
Holly Burrows ◽  
Benoit Talbot ◽  
Roman McKay ◽  
Andreea Slatculescu ◽  
James Logan ◽  
...  
Keyword(s):  
Lyme Disease ◽  
Rural Areas ◽  
Disease Risk ◽  
Ixodes Scapularis ◽  
Urban Expansion ◽  
Ottawa River ◽  
Urban Core ◽  
The Face ◽  
Population Establishment ◽  
The City

Canadians face an emerging threat of Lyme disease due to the northward expansion of the tick vector, Ixodes scapularis. We evaluated the degree of I. scapularis population establishment and Borrelia burgdorferi occurrence in the city of Ottawa, Ontario, Canada from 2017–2019 using active surveillance at 28 sites. We used a field indicator tool developed by Clow et al. to determine the risk of I. scapularis establishment for each tick cohort at each site using the results of drag sampling. Based on results obtained with the field indicator tool, we assigned each site an ecological classification describing the pattern of tick colonization over two successive cohorts (cohort 1 was comprised of ticks collected in fall 2017 and spring 2018, and cohort 2 was collected in fall 2018 and spring 2019). Total annual site-specific I. scapularis density ranged from 0 to 16.3 ticks per person-hour. Sites with the highest density were located within the Greenbelt zone, in the suburban/rural areas in the western portion of the city of Ottawa, and along the Ottawa River; the lowest densities occurred at sites in the suburban/urban core. B. burgdorferi infection rates exhibited a similar spatial distribution pattern. Of the 23 sites for which data for two tick cohorts were available, 11 sites were classified as “high-stable”, 4 were classified as “emerging”, 2 were classified as “low-stable”, and 6 were classified as “non-zero”. B. burgdorferi-infected ticks were found at all high-stable sites, and at one emerging site. These findings suggest that high-stable sites pose a risk of Lyme disease exposure to the community as they have reproducing tick populations with consistent levels of B. burgdorferi infection. Continued surveillance for I. scapularis, B. burgdorferi, and range expansion of other tick species and emerging tick-borne pathogens is important to identify areas posing a high risk for human exposure to tick-borne pathogens in the face of ongoing climate change and urban expansion.

scholarly journals Timing between successive introduction events determines establishment success in bacteria with an Allee effect

2019 ◽  
Vol 286 (1902) ◽  
pp. 20190598 ◽  
Author(s):  
Michael D. Dressler ◽  
Josue Conde ◽  
Omar Tonsi Eldakar ◽  
Robert P. Smith
Keyword(s):  
Infectious Disease ◽  
Allee Effect ◽  
Propagule Pressure ◽  
Temporal Distribution ◽  
Invasion Biology ◽  
Theoretical Studies ◽  
Establishment Success ◽  
Propagule Size ◽  
Population Establishment ◽  
Principal Parts

Propagule pressure is a leading determinant of population establishment. Yet, an experimental understanding of how propagule size and number (two principal parts of propagule pressure) determine establishment success remains incomplete. Theoretical studies suggest that the timing between introduction events, a component of propagule number, can influence establishment success. However, this dynamic has rarely been explored experimentally. Using Escherichia coli engineered with an Allee effect, we investigated how the timing of two introduction events influences establishment. For populations introduced below the Allee threshold, establishment occurred if the time between two introduction events was sufficiently short, with the length of time between events further reduced by reducing growth rate. Interestingly, we observed that as the density of bacteria introduced in one introduction event increased, the time between introduction events that allowed for establishment increased. Using a mathematical model, we provide support that the mechanism behind these trends is the ability of the first population to modify the environment, which can pave the way for establishment of the second population. Our results provide experimental evidence that the temporal distribution of introduction events regulates establishment, furthering our understanding of propagule pressure and may have implications in invasion biology and infectious disease.

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