scholarly journals The Disconnect Between Short- and Long-Term Population Projections for Plant Reintroductions

2022 ◽  
Vol 2 ◽  
Author(s):  
Lalasia Bialic-Murphy ◽  
Tiffany M. Knight ◽  
Kapua Kawelo ◽  
Orou G. Gaoue
Keyword(s):  
Population Growth ◽  
Population Projections ◽  
Population Growth Rates ◽  
Population Extinction ◽  
Management Actions ◽  
Natural Seedling ◽  
Short And Long Term ◽  
Plant Reintroductions ◽  
Over Time

The reintroduction of rare species in natural preserves is a commonly used restoration strategy to prevent species extinction. An essential first step in planning successful reintroductions is identifying which life stages (e.g., seeds or large adults) should be used to establish these new populations. Following this initial establishment phase, it is necessary to determine the level of survival, growth, and recruitment needed to maintain population persistence over time and identify management actions that will achieve these goals. In this 5-year study, we projected the short- and long-term population growth rates of a critically endangered long-lived shrub, Delissea waianaeensis. Using this model system, we show that reintroductions established with mature individuals have the lowest probability of quasi-population extinction (10 individuals) and the highest increase in population abundance. However, our results also demonstrate that short-term increases in population abundances are overly optimistic of long-term outcomes. Using long-term stochastic model simulations, we identified the level of natural seedling regeneration needed to maintain a positive population growth rate over time. These findings are relevant for planning future reintroduction efforts for long-lived species and illustrate the need to forecast short- and long-term population responses when evaluating restoration success.

Demography of the lizard Sceloporus grammicus: exploring temporal variation in population dynamics

2008 ◽  
Vol 86 (12) ◽  
pp. 1397-1409 ◽  
Author(s):  
J. J. Zúñiga-Vega ◽  
F. R. Méndez-de la Cruz ◽  
O. Cuellar
Keyword(s):  
Population Growth ◽  
Population Projections ◽  
Relative Importance ◽  
Population Stability ◽  
Elasticity Analysis ◽  
Yearly Variation ◽  
Population Growth Rates ◽  
Resampling Procedure ◽  
Sceloporus Grammicus

We conducted a 5 year demographic study in one population of the viviparous lizard Sceloporus grammicus Wiegmann, 1828 in central México. The population was structured in three size classes (juveniles, small adults, and asymptotic adults) for which we estimated annual survival and fecundity rates. A population projection matrix was constructed for each annual transition. All of them resulted in finite rates of population growth (λ) that, although variable from year to year (from 0.808 to 1.065), were not significantly different than unity, indicating population stability. Elasticity analysis revealed that survival staying in the same size class was the demographic process that made the greatest contribution to λ values in most years. Similarly, the stasis of large adults was the vital rate with the highest relative importance for population persistence. To incorporate the observed yearly variation in long-term population projections, we used a mean matrix, a stochastic simulation, and a resampling procedure. All these resulted in long-term population growth rates that were not significantly different than unity. Our results indicate overall demographic stability for the studied population of S. grammicus.

scholarly journals Pattern of variation in avian population growth rates

2002 ◽  
Vol 357 (1425) ◽  
pp. 1185-1195 ◽  
Author(s):  
Bernt–Erik Sæther ◽  
Steinar Engen
Keyword(s):  
Population Dynamics ◽  
Population Growth ◽  
Growth Rates ◽  
Specific Growth ◽  
Population Projections ◽  
Stochastic Effects ◽  
Density Regulation ◽  
Population Growth Rates ◽  
Specific Growth Rates

A central question in population ecology is to understand why population growth rates differ over time. Here, we describe how the long–term growth of populations is not only influenced by parameters affecting the expected dynamics, for example form of density dependence and specific population growth rate, but is also affected by environmental and demographic stochasticity. Using long–term studies of fluctuations of bird populations, we show an interaction between the stochastic and the deterministic components of the population dynamics: high specific growth rates at small densities r 1 are typically positively correlated with the environmental variance σ e 2 . Furthermore, θ, a single parameter describing the form of the density regulation in the theta–logistic density–regulation model, is negatively correlated with r 1 . These patterns are in turn correlated with interspecific differences in life–history characteristics. Higher specific growth rates, larger stochastic effects on the population dynamics and stronger density regulation at small densities are found in species with large clutch sizes or high adult mortality rates than in long–lived species. Unfortunately, large uncertainties in parameter estimates, as well as strong stochastic effects on the population dynamics, will often make even short–term population projections unreliable. We illustrate that the concept of population prediction interval can be useful in evaluating the consequences of these uncertainties in the population projections for the choice of management actions.

Advertising in disguise? How disclosure and content features influence the effects of native advertising

2020 ◽  
Vol 45 (3) ◽  
pp. 303-324
Author(s):  
Johannes Beckert ◽  
Thomas Koch ◽  
Benno Viererbl ◽  
Nora Denner ◽  
Christina Peter
Keyword(s):  
Experimental Studies ◽  
Brand Attitudes ◽  
News Websites ◽  
Short And Long Term ◽  
Message Sidedness ◽  
Over Time

AbstractNative advertising has recently become a prominent buzzword for advertisers and publishers alike. It describes advertising formats which closely adapt their form and style to the editorial environment they appear in, intending to hide the commercial character of these ads. In two experimental studies, we test how advertising disclosures in native ads on news websites affect recipients’ attitudes towards a promoted brand in a short and long-term perspective. In addition, we explore persuasion through certain content features (i. e., message sidedness and use of exemplars) and how they affect disclosure effects. Results show that disclosures increase perceived persuasive intent but do not necessarily decrease brand attitudes. However, disclosure effects do not persist over time and remain unaffected by content features.

Assessment of invasive rodent impacts on island avifauna: methods, limitations and the way forward

2015 ◽  
Vol 42 (2) ◽  
pp. 185 ◽  
Author(s):  
Lise Ruffino ◽  
Diane Zarzoso-Lacoste ◽  
Eric Vidal
Keyword(s):  
Population Growth ◽  
Population Level ◽  
Bird Conservation ◽  
Bird Population ◽  
Breeding Parameters ◽  
Population Growth Rates ◽  
Bird Populations ◽  
Field Evidence ◽  
Bird Breeding

Bird conservation is nowadays a strong driving force for prioritising rodent eradications, but robust quantitative estimates of impacts are needed to ensure cost-effectiveness of management operations. Here, we review the published literature to investigate on what methodological basis rodent effects on island bird communities have been evaluated for the past six decades. We then discuss the advantages and limitations of each category of methods for the detection and quantification of impacts, and end with some recommendations on how to strengthen current approaches and extend our knowledge on the mechanisms of impacts. Impact studies (152 studies considered) emphasised seabirds (67%), black rats (63%) and the Pacific Ocean (57%). Among the most commonly used methods to study rodent impacts on birds were the observation of dead eggs or empty nests while monitoring bird breeding success, and the analyses of rodent diets, which can both lead to misleading conclusions if the data are not supported by direct field evidence of rodent predation. Direct observations of rodent–bird interactions (19% of studies) are still poorly considered despite their potential to reveal cryptic behaviours and shed light on the mechanisms of impacts. Rodent effects on birds were most often measured as a change or difference in bird breeding parameters (74% of studies), while estimates of bird population growth rates (4%) are lacking. Based on the outcomes of this literature review, we highlight the need for collecting unbiased population-level estimates of rodent impacts, which are essential prerequisites for predicting bird population growth scenarios and prioritising their conservation needs. This could be achieved by a more systematic integration of long-term monitoring of bird populations into rodent management operations and modelling bird population dynamics. We also strongly recommend including various complementary methods in impact assessment strategies to unravel complex interactions between rodents and birds and avoid faulty evidence. Finally, more research should be devoted to a better understanding of the cases of non-impacts (i.e. long-term coexistence) and those impacts mediated by mechanisms other than predation and ecosystem-level processes.

An Evaluation of RNA–DNA Ratio as a Measure of Long-Term Growth in Fish Populations

1973 ◽  
Vol 30 (2) ◽  
pp. 195-199 ◽  
Author(s):  
Terry A. Haines
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Growth Rates ◽  
Population Growth Rate ◽  
Environmental Changes ◽  
Age Distribution ◽  
Smallmouth Bass ◽  
Fish Populations ◽  
Population Growth Rates

The value of RNA–DNA ratio as a measure of long-term growth of fish populations under semi-natural conditions and when subjected to environmental manipulations was determined. Populations of carp and smallmouth bass of known age distribution were established in artificial ponds maintained at two fertility levels. After 15 months, population growth rates (as percent increase in weight) and RNA–DNA ratios of muscle tissue from selected fish were measured. Each species exhibited a range of population growth rates. The relation between population growth rate and individual fish RNA–DNA ratio for each species was significant. When reproduction occurred, the relation was not significant unless young-of-the-year fish were excluded from population growth rate calculations. Age of fish was also found to have an important effect on RNA–DNA ratio, with the ratio being higher in younger fish.RNA–DNA ratio can be a reliable indicator of long-term population growth in fish when population age structure is known and recruitment is controlled. The method has potential for use in detecting response to environmental changes before growth rate changes become severe.

Tracking Emotions over Time (the “ARC”)

2021 ◽  
pp. 81-92
Author(s):  
Heather Thompson-Brenner ◽  
Melanie Smith ◽  
Gayle Brooks ◽  
Dee Ross Franklin ◽  
Hallie Espel-Huynh ◽  
...  
Keyword(s):  
Emotional Responses ◽  
Emotional Experiences ◽  
Short And Long Term ◽  
Long Term Consequences ◽  
And Behaviors ◽  
Over Time

The primary goal for this session is for clients to explore and learn how emotional experiences unfold. This allows clients to learn from their emotional experiences and how these experiences can influence their later behaviors and emotions. During this session, clients learn the steps that unfold over time in emotions: antecedent (A, what happened before), response (R, which includes thoughts, physical sensations, and behaviors/urges), and consequence (C, what happens after). Clients learn to look for patterns in their emotional triggers. They also learn to explore short- and long-term consequences of their emotional responses. Form 8.1: The ARC of Emotional Experiences is introduced.

The Final Score

2020 ◽  
pp. 201-210
Author(s):  
Steven M. Ortiz
Keyword(s):  
Lived Experience ◽  
Longitudinal Research ◽  
Long Term Effects ◽  
Professional Athlete ◽  
The Past ◽  
Personal Empowerment ◽  
Final Score ◽  
Short And Long Term ◽  
Over Time

The conclusion provides some final observations about the longitudinal research itself and its short- and long-term effects on the women involved. It briefly touches on the few areas of the sport marriage that have seen improvement in the past few decades, discusses the conscious decisions the women make to continue normalizing the career-dominated marriage, and reports on how the marriages fared over time. It also describes the women’s personal empowerment as a result of their participation in the research. Finally, it summarizes the advice and suggested keys to a successful sport marriage that the wives in both studies offered, based on their lived experience. This overview essentially describes how and why the wife of a male professional athlete must adapt to realities if she wants her marriage to survive her husband’s career and retirement.

Rapid Population Growth and Long-term Development

2020 ◽  
pp. 164-177
Author(s):  
Giovanni Andrea Cornia
Keyword(s):  
Population Growth ◽  
Resource Availability ◽  
Demographic Transition ◽  
Population Growth Rate ◽  
Physical Capital ◽  
Population Projections ◽  
World Population ◽  
Rapid Population Growth ◽  
The World

This chapter reviews population trends over the last two hundred years and population projections to the end of this century. In 2100 the world population will have stabilized but its geographical distribution will have substantially changed compared to 2015. The chapter then discusses the five stages of the demographic transition, and different neo-Malthusian and non-Malthusian theories of the relation between population growth and economic development. It emphasizes in particular the effects of rapid population growth on land and resource availability, human capital formation, population quality, the accumulation of physical capital, employment, wages, and income inequality. The effects of rapid population growth rate over a given period were found to change in line with the population size and density at the beginning of the period considered.

scholarly journals Pediatric bladder augmentation – Panacea or Pandora’s box?

2020 ◽  
Vol 14 (6) ◽  
Author(s):  
James P.J. Ross ◽  
Melise Keays ◽  
Christopher Neville ◽  
Michael Leonard ◽  
Luis Guerra
Keyword(s):  
Stone Formation ◽  
Bladder Capacity ◽  
Primary Objective ◽  
Bladder Augmentation ◽  
Pediatric Hospital ◽  
Short And Long Term ◽  
Tract Infections ◽  
Stomal Stenosis ◽  
Over Time

Introduction: Bladder augmentation is a surgery that can increase bladder capacity and compliance. The objective of this study was to provide a longitudinal review of pediatric bladder augmentation at a tertiary Canadian center. Methods: A retrospective review was performed on patients who underwent bladder augmentation at a tertiary pediatric hospital between 1986 and 2014. The primary objective was short- and long-term complications of augmentation. Secondary objectives were to review number of augmentation procedures performed over time and the utility of routine postoperative cystograms. Results: A total of 56 procedures were performed on 54 patients (28 males, 26 females) of mean age 10 years (standard deviation [SD] 5) and mean followup eight years (SD 5). The most common bowel segment used was ileum (87.5%). Twenty-eight patients (50%) received catheterizable channels. Overall complication rate was 15%, and the most common complications were urinary tract infections (68.5%), worsening hydronephrosis (14.8%), bladder stone formation (14%), and hematuria (13%). In total, 19 of 54 (35.2%) patients returned to the operating room. The incidence of bladder perforation was 3.6%. Complications with the catheterizable channel occurred in 13 of 28 (46.4%), of which 10 were related to stomal stenosis. Forty patients had postoperative cystograms and extravasation was seen in three (7.5%). There was no malignancy during the followup. Only four augmentations were performed from 2008–2014. Conclusions: Bladder augmentation likely represents a safe surgical treatment option. Extravasation on postoperative cystogram was uncommon and thus it may not be indicated routinely. The number of augmentation procedures performed has declined in recent years.

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