Population Trends of Monarch Butterflies (Lepidoptera: Nymphalidae) Migrating From the Core of Canada’s Eastern Breeding Population

2020 ◽  
Author(s):  
Danielle M Ethier
Keyword(s):  
Count Data ◽  
Lake Erie ◽  
Local Population ◽  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
Breeding Population ◽  
Future Research ◽  
Population Declines ◽  
Annual Life Cycle ◽  
The Core

Abstract The Monarch butterfly (Danaus plexippus) (Linnaeus 1758) is being considered for up-listing to Endangered under the Canadian federal Species-at-Risk Act due to population declines recorded throughout the annual life cycle. Understanding local population dynamics is therefore necessary to assess the effect of environmental and human induced stressors, and to establish a benchmark from which management success can be measured through time. Using fall count data collected along the Lake Erie shoreline, which captures migrants moving south from the core eastern breeding population in Canada, monarch abundance trends are quantified. Count data from three migration count sites and one roost site were analyzed following similar methods as Crewe and McCracken (2015) to make findings comparable. Two of these datasets are newly compiled and are analyzed here for the first time. Results suggest that during the past 10 yr, the number of migrating monarchs along the north shore of Lake Erie has been stable [mean: −3.05% per year, credibility interval (CI): −13.15, 9.97], which is consistent with changes being observed on the wintering grounds. Only migration counts collected between 1995 and 2018 at the Long Point sites demonstrated significant abundance declines (5.25% per year, CI: −8.60, −1.39), which is a similar results to previous analysis of this dataset. Opportunities for future research are discussed within the context of using monarch count data for future conservation efforts.

Antecedents of Family Conflict in Uganda

2020 ◽  
Vol 12 (3) ◽  
pp. 35-54
Author(s):  
Rogers Matama ◽  
Kezia H. Mkwizu
Keyword(s):  
Content Analysis ◽  
Social Identity ◽  
Sample Size ◽  
Social Identity Theory ◽  
Family Conflict ◽  
Qualitative Approach ◽  
Future Research ◽  
Family Conflicts ◽  
The Core ◽  
Quantitative Studies

The purpose of this study was to explore the antecedents of family conflict in Uganda. A qualitative approach was used in this study. A sample size of 139 participants provided data which was subjected to content analysis. Results revealed that the core themes associated with family conflict are finances and priority of resources. Further findings show that differences in tastes and interests, selfishness and lack of communication played a key role as causes of family conflicts. The implication of this study is that finances and priority of resources are antecedents of family conflict in the context of Uganda. Therefore, the antecedents of family conflict that emerged from this study can be understood, defined and analyzed through the lens of social identity theory. Future research may include conducting quantitative studies with a particular demographic using the themes that have emerged from this study.

Citizen Deliberation Online

2019 ◽  
pp. 689-712
Author(s):  
Patrícia Rossini ◽  
Jennifer Stromer-Galley
Keyword(s):  
Political Engagement ◽  
Future Research ◽  
The Internet ◽  
Digital Platforms ◽  
The Core ◽  
Political Conversation ◽  
Political Talk ◽  
Citizen Deliberation ◽  
The Impact

Political conversation is at the heart of democratic societies, and it is an important precursor of political engagement. As society has become intertwined with the communication infrastructure of the Internet, we need to understand its uses and the implications of those uses for democracy. This chapter provides an overview of the core topics of scholarly concern around online citizen deliberation, focusing on three key areas of research: the standards of quality of communication and the normative stance on citizen deliberation online; the impact and importance of digital platforms in structuring political talk; and the differences between formal and informal political talk spaces. After providing a critical review of these three major areas of research, we outline directions for future research on online citizen deliberation.

scholarly journals Monarch butterfly and milkweed declines substantially predate the use of genetically modified crops

2019 ◽  
Vol 116 (8) ◽  
pp. 3006-3011 ◽  
Author(s):  
J. H. Boyle ◽  
H. J. Dalgleish ◽  
J. R. Puzey
Keyword(s):  
Genetically Modified ◽  
Danaus Plexippus ◽  
Genetically Modified Crops ◽  
Monarch Butterfly ◽  
The United States ◽  
Gm Crops ◽  
Herbicide Resistant ◽  
The Past ◽  
Scientific Attention ◽  
Herbicide Use

Monarch butterfly (Danaus plexippus) decline over the past 25 years has received considerable public and scientific attention, in large part because its decline, and that of its milkweed (Asclepias spp.) host plant, have been linked to genetically modified (GM) crops and associated herbicide use. Here, we use museum and herbaria specimens to extend our knowledge of the dynamics of both monarchs and milkweeds in the United States to more than a century, from 1900 to 2016. We show that both monarchs and milkweeds increased during the early 20th century and that recent declines are actually part of a much longer-term decline in both monarchs and milkweed beginning around 1950. Herbicide-resistant crops, therefore, are clearly not the only culprit and, likely, not even the primary culprit: Not only did monarch and milkweed declines begin decades before GM crops were introduced, but other variables, particularly a decline in the number of farms, predict common milkweed trends more strongly over the period studied here.

scholarly journals High Survivorship of First-Generation Monarch Butterfly Eggs to Third Instar Associated with a Diverse Arthropod Community

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 567
Author(s):  
Misty Stevenson ◽  
Kalynn L. Hudman ◽  
Alyx Scott ◽  
Kelsey Contreras ◽  
Jeffrey G. Kopachena
Keyword(s):  
Host Plants ◽  
First Generation ◽  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
Conservation Strategies ◽  
North Texas ◽  
Ecological Processes ◽  
Area Of Occupancy ◽  
Predator Abundance ◽  
A Site

Based on surveys of winter roost sites, the eastern migratory population of the monarch butterfly (Danaus plexippus) in North America appears to have declined in the last 20 years and this has prompted the implementation of numerous conservation strategies. However, there is little information on the survivorship of first-generation monarchs in the core area of occupancy in Texas, Oklahoma, and Louisiana where overwinter population recovery begins. The purpose of this study was to determine the survivorship of first-generation eggs to third instars at a site in north Texas and to evaluate host plant arthropods for their effect on survivorship. Survivorship to third instar averaged 13.4% and varied from 11.7% to 15.6% over three years. The host plants harbored 77 arthropod taxa, including 27 predatory taxa. Despite their abundance, neither predator abundance nor predator richness predicted monarch survival. However, host plants upon which monarchs survived often harbored higher numbers of non-predatory arthropod taxa and more individuals of non-predatory taxa. These results suggest that ecological processes may have buffered the effects of predators and improved monarch survival in our study. The creation of diverse functional arthropod communities should be considered for effective monarch conservation, particularly in southern latitudes.

Stranding cases of endangered Ganges river dolphins in the Ghaghara–Sharada irrigation canals, Ganges river basin, India: conservation implications

Mammalia ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Shakti Prajapati
Keyword(s):  
River Basin ◽  
Local Population ◽  
Uttar Pradesh ◽  
Ganges River ◽  
Population Declines ◽  
Irrigation Canals ◽  
Indus River ◽  
River Dolphin ◽  
Conservation Implications ◽  
Media Reports

AbstractPopulations of endangered Ganges and Indus river dolphins have been under severe threat from diversion of river water by dams, barrages, and canal networks across the Indus and Ganges–Brahmaputra river basins. River dolphins prefer deep water and might enter irrigation canals in the dry-season, getting stranded there. Stranding can cause mortality and local population declines, and poses an emerging challenge to river dolphin conservation efforts. In Pakistan’s Indus river basin, stranding rates of Indus dolphins in irrigation canals are high, and well-coordinated rescue-release operations are undertaken. Despite commendable river dolphin rescue efforts in some parts of India, stranding cases are not always reported. From open-access media reports (2007–08 to 2017–18), I found 26 stranding cases of Ganges river dolphins from the Ghaghara–Sharada canal network across seven districts of Uttar Pradesh, India. Of these, 62% reports were from 2015 to 2016. Most cases occurred in secondary and tertiary canal branches. Interviews with fishers, farmers, and government officials revealed low awareness of stranding cases. Stranded dolphins might have no chance of returning to their source habitat, unless rescued. From my results, I discuss how current barrage-canal operations could influence dolphin stranding risk, and their implications for flow management in the Ghaghara–Sharada river basin.

Using the Core Concepts Framework to Understand Three Generations of Inclusive Practices

Inclusion ◽  
2014 ◽  
Vol 2 (3) ◽  
pp. 237-247 ◽  
Author(s):  
Karrie A. Shogren ◽  
Michael L. Wehmeyer
Keyword(s):  
Research Policy ◽  
Future Research ◽  
Third Generation ◽  
Inclusive Practices ◽  
Policy And Practice ◽  
Inclusive Practice ◽  
The Core ◽  
Three Generations ◽  
Core Concepts ◽  
The Relationship

Abstract This article analyzes the relationship between the core concepts of disability policy and the three generations of inclusive practices. Specifically, we review the three generations of inclusive practice, highlighting the core concepts that have been most strongly emphasized during each generation of inclusive practices. Because we are early in the third generation of inclusive practices, we conclude by examining how the core concepts can guide and direct third generation inclusive practices and how future research, policy, and practice can actualize the aspirational values of all of the core concepts to enable desired outcomes.

scholarly journals Pretty Picky for a Generalist: Impacts of Toxicity and Nutritional Quality on Mantid Prey Processing

2017 ◽  
Vol 46 (3) ◽  
pp. 626-632 ◽  
Author(s):  
Jamie L. Rafter ◽  
Justin F. Vendettuoli ◽  
Liahna Gonda-King ◽  
Daniel Niesen ◽  
Navindra P. Seeram ◽  
...  
Keyword(s):  
C:N Ratio ◽  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
The Body ◽  
Gut Contents ◽  
Corn Borers ◽  
Body Tissues ◽  
Heterogeneous Quality ◽  
Behavioral Trials

Abstract Prey have evolved a number of defenses against predation, and predators have developed means of countering these protective measures. Although caterpillars of the monarch butterfly,Danaus plexippus L., are defended by cardenolides sequestered from their host plants, the Chinese mantidTenodera sinensis Saussure guts the caterpillar before consuming the rest of the body. We hypothesized that this gutting behavior might be driven by the heterogeneous quality of prey tissue with respect to toxicity and/or nutrients. We conducted behavioral trials in which mantids were offered cardenolide-containing and cardenolide-freeD. plexippus caterpillars and butterflies. In addition, we fed mantids starved and unstarvedD. plexippus caterpillars from each cardenolide treatment and nontoxicOstrinia nubilalis Hübner caterpillars. These trials were coupled with elemental analysis of the gut and body tissues of bothD. plexippus caterpillars and corn borers. Cardenolides did not affect mantid behavior: mantids gutted both cardenolide-containing and cardenolide-free caterpillars. In contrast, mantids consumed bothO. nubilalis and starvedD. plexippus caterpillars entirely.Danaus plexippus body tissue has a lower C:N ratio than their gut contents, whileO. nubilalis have similar ratios; gutting may reflect the mantid’s ability to regulate nutrient uptake. Our results suggest that post-capture prey processing by mantids is likely driven by a sophisticated assessment of resource quality.

Conclusion: social policy in an era of competition

2017 ◽  
pp. 203-212
Author(s):  
Dan Horsfall ◽  
John Hudson
Keyword(s):  
Social Policy ◽  
Welfare State ◽  
Empirical Analysis ◽  
Welfare States ◽  
Future Research ◽  
The Core ◽  
Competition State ◽  
State Welfare ◽  
Policy Analysts

This concluding chapter highlights key arguments from across the book in order to set out an integrated agenda for future research. Theoretically rooted analyses must be at the core of such an agenda. The inter-pollination/cross-fertilisation of ideas from many disciplines is important in developing an understanding of the complex and multi-faceted ways in which competition is influencing welfare states. However, while theory is central to this agenda, it must also be rooted in detailed empirical analysis. In looking to transcend the competition state/welfare state dichotomy, this interplay between theory and evidence is key, and where theoretically rooted social policy analysts can add particular value to current debates.

scholarly journals Cardenolides, toxicity, and the costs of sequestration in the coevolutionary interaction between monarchs and milkweeds

2021 ◽  
Vol 118 (16) ◽  
pp. e2024463118
Author(s):  
Anurag A. Agrawal ◽  
Katalin Böröczky ◽  
Meena Haribal ◽  
Amy P. Hastings ◽  
Ronald A. White ◽  
...  
Keyword(s):  
Danaus Plexippus ◽  
Monarch Butterfly ◽  
Chemical Defenses ◽  
Trade Off ◽  
Asclepias Curassavica ◽  
Plant Chemical ◽  
Whole Plants ◽  
Benefits And Costs

For highly specialized insect herbivores, plant chemical defenses are often co-opted as cues for oviposition and sequestration. In such interactions, can plants evolve novel defenses, pushing herbivores to trade off benefits of specialization with costs of coping with toxins? We tested how variation in milkweed toxins (cardenolides) impacted monarch butterfly (Danaus plexippus) growth, sequestration, and oviposition when consuming tropical milkweed (Asclepias curassavica), one of two critical host plants worldwide. The most abundant leaf toxin, highly apolar and thiazolidine ring–containing voruscharin, accounted for 40% of leaf cardenolides, negatively predicted caterpillar growth, and was not sequestered. Using whole plants and purified voruscharin, we show that monarch caterpillars convert voruscharin to calotropin and calactin in vivo, imposing a burden on growth. As shown by in vitro experiments, this conversion is facilitated by temperature and alkaline pH. We next employed toxin-target site experiments with isolated cardenolides and the monarch’s neural Na+/K+-ATPase, revealing that voruscharin is highly inhibitory compared with several standards and sequestered cardenolides. The monarch’s typical >50-fold enhanced resistance to cardenolides compared with sensitive animals was absent for voruscharin, suggesting highly specific plant defense. Finally, oviposition was greatest on intermediate cardenolide plants, supporting the notion of a trade-off between benefits and costs of sequestration for this highly specialized herbivore. There is apparently ample opportunity for continued coevolution between monarchs and milkweeds, although the diffuse nature of the interaction, due to migration and interaction with multiple milkweeds, may limit the ability of monarchs to counteradapt.

Introduction

2010 ◽  
Vol 9 (5) ◽  
pp. 563-593
Author(s):  
Benjamin Gregg
Keyword(s):  
Japanese Society ◽  
Economic Reforms ◽  
Future Research ◽  
Minority Population ◽  
The European Union ◽  
Special Issue ◽  
Individual Motivation ◽  
Comparative Sociology ◽  
The Core ◽  
Problematic Integration

AbstractI introduce the five articles in this special issue of Comparative Sociology as each applies the theory of enlightened localism. First I outline the theory in question and then highlight those aspects that each of the authors deploys, the criticisms each levels at it, and the suggestions each offers toward its improvement. Lea Ypi applies the theory to human rights in a way that might reconcile universal norms with the need for individual motivation that can only be local. Jonathan White uses the theory to develop a conception of the European Union that would preserve rather than, as now, repress the partisan politicking at the core of democracy. Junmin Wang finds the theory helpful in analyzing the unintended decentralization of political power in China as a consequence of recent economic reforms. Ko Hasegawa seeks an enlightened localist solution to the problematic integration of a minority population into mainstream Japanese society. Manuel Ahedo enlists the theory in combating ghettoized schooling all too typical for immigrant children in Europe with ideas for integrating the children of immigrants with those of long-established residents. I conclude by listing some of the questions raised by the articles and to be addressed by future research ‐ concerns that might move an enlightened localist approach forward.

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