scholarly journals Resilience or Catastrophe? A possible state change for monarch butterflies in the West

2021 ◽  
Author(s):  
Elizabeth Crone ◽  
Cheryl Schultz
Keyword(s):  
Sudden Change ◽  
Protozoan Parasite ◽  
Monarch Butterfly ◽  
Western United States ◽  
State Change ◽  
Recent Past ◽  
The West ◽  
Monarch Butterflies ◽  
Resident Population ◽  
Butterfly Population

In the western United States, the population of migratory monarch butterflies is on the brink of collapse, having dropped from several million butterflies at coastal overwintering sites in the 1980’s to about 2000 butterflies in the winter of 2020-21. At the same time, a resident (non-migratory) monarch butterfly population in urban gardens seems to be expanding northward. If anything, this urban population has been growing in recent years. We explore the meaning of these changes. The new resident population is not sufficient to make up for the loss of the migratory population; there are still orders of magnitude fewer butterflies now than in the recent past. The resident population also probably lacks the demographic capacity to expand its range inland during summer months, due to higher levels of infection by a protozoan parasite, and subsequently lower survival and fecundity. Nonetheless, the resident population may have the capacity to persist. This sudden change emphasizes the extent to which environmental change can have unexpected consequences. It also demonstrates how quickly these changes can happen. We hope it will provoke discussion about how we define resilience and viability in changing environments.

scholarly journals Milkweed loss in agricultural fields because of herbicide use: effect on the monarch butterfly population: Herbicide use and monarch butterflies

2017 ◽  
Author(s):  
John M. Pleasants ◽  
Karen S. Oberhauser
Keyword(s):  
Population Size ◽  
Genetically Modified ◽  
Monarch Butterfly ◽  
Agricultural Fields ◽  
Monarch Butterflies ◽  
Glyphosate Herbicide ◽  
Butterfly Population ◽  
Conservation Threats ◽  
Herbicide Use ◽  
The U.S

1. The size of the Mexican overwintering population of monarch butterflieshas decreased over the last decade. Approximately half of these butterflies comefrom the U.S. Midwest where larvae feed on common milkweed. There has been alarge decline in milkweed in agricultural fields in the Midwest over the last decade.This loss is coincident with the increased use of glyphosate herbicide in conjunctionwith increased planting of genetically modified (GM) glyphosate-tolerant corn(maize) and soybeans (soya).2. We investigate whether the decline in the size of the overwintering populationcan be attributed to a decline in monarch production owing to a loss of milkweeds inagricultural fields in the Midwest. We estimate Midwest annual monarch productionusing data on the number of monarch eggs per milkweed plant for milkweeds in differenthabitats, the density of milkweeds in different habitats, and the area occupiedby those habitats on the landscape.3. We estimate that there has been a 58% decline in milkweeds on the Midwestlandscape and an 81% decline in monarch production in the Midwest from 1999 to2010. Monarch production in the Midwest each year was positively correlated withthe size of the subsequent overwintering population in Mexico. Taken together, theseresults strongly suggest that a loss of agricultural milkweeds is a major contributorto the decline in the monarch population.4. The smaller monarch population size that has become the norm will make thespecies more vulnerable to other conservation threats.

scholarly journals A Climatology of 500-hPa Closed Lows in the Northeastern Pacific Ocean, 1948–2011

2014 ◽  
Vol 53 (6) ◽  
pp. 1578-1592 ◽  
Author(s):  
Nina S. Oakley ◽  
Kelly T. Redmond
Keyword(s):  
United States ◽  
Pacific Ocean ◽  
Interannual Variability ◽  
West Coast ◽  
The United States ◽  
Western United States ◽  
The West ◽  
Reanalysis Dataset ◽  
The Pacific ◽  
Northeastern Pacific

AbstractThe northeastern Pacific Ocean is a preferential location for the formation of closed low pressure systems. These slow-moving, quasi-barotropic systems influence vertical stability and sustain a moist environment, giving them the potential to produce or affect sustained precipitation episodes along the west coast of the United States. They can remain motionless or change direction and speed more than once and thus often pose difficult forecast challenges. This study creates an objective climatological description of 500-hPa closed lows to assess their impacts on precipitation in the western United States and to explore interannual variability and preferred tracks. Geopotential height at 500 hPa from the NCEP–NCAR global reanalysis dataset was used at 6-h and 2.5° × 2.5° resolution for the period 1948–2011. Closed lows displayed seasonality and preferential durations. Time series for seasonal and annual event counts were found to exhibit strong interannual variability. Composites of the tracks of landfalling closed lows revealed preferential tracks as the features move inland over the western United States. Correlations of seasonal event totals for closed lows with ENSO indices, the Pacific decadal oscillation (PDO), and the Pacific–North American (PNA) pattern suggested an above-average number of events during the warm phase of ENSO and positive PDO and PNA phases. Precipitation at 30 U.S. Cooperative Observer stations was attributed to closed-low events, suggesting 20%–60% of annual precipitation along the West Coast may be associated with closed lows.

The tompon-tany and the tompon-drano in the History of Central and Western Madagascar

1982 ◽  
Vol 9 ◽  
pp. 61-76
Author(s):  
Finn Fuglestad
Keyword(s):  
Seventeenth Century ◽  
West Coast ◽  
Religious Beliefs ◽  
Eastern Coast ◽  
Recent Past ◽  
The West ◽  
Political Consequences ◽  
The People ◽  
History Of ◽  
Conceptual Revolution

At some undefined time in the fairly recent past central and western Madagascar witnessed a conceptual 'revolution' which had far-reaching political consequences. The religious beliefs and symbols which constituted the main ingredients of this 'revolution'--and probably also the people who propagated them--were in some way connected with the Zafindraminia-Antanosy and the Anteimoro of the southeastern and eastern coast. It is quite clear that these and similar groups had been strongly influenced by Islam and that they practiced what could perhaps be described as a corrupt or diluted Islam or a syncretic 'pagan' Muslim religion. (It is significant that as their name indicates the Zafindraminia claim descent from Raminia who they hold to have been the mother of Muhammad.) One of the main ingredients of this religion was the cult of the ody or guardian amulets, objects usually made of wood which are strikingly reminiscent of the so-called “charms” or “gris-gris” sold by Muslim clerics over much of Africa. Another ingredient is represented by the institution of ombiasy. The ombiasy (the main manufacturers of ody) whom the Frenchman Etienne de Flacourt at Fort-Dauphin in the seventeenth century took to be Muslim clerics were originally the “priests” (or the “devins guérisseurs,” according to Hubert Deschamps) of the Anteimoro and the Zafindraminia-Antanosy. Subsequently this institution was disseminated throughout nearly the whole of Madagascar. Yet another ingredient was the system of divination known as sikidy, which also spread to other parts of Madagascar, including Imerina and the Sakalava country.These beliefs, symbols, and institutions deeply influenced the people of the west coast (the present-day Sakalava country) and of central Madagascar (Imerina and Betsileo country).

scholarly journals Studying the snow leopard: reconceptualizing conservation across the China–India border

BJHS Themes ◽  
2016 ◽  
Vol 1 ◽  
pp. 169-198
Author(s):  
MICHAEL LEWIS ◽  
E. ELENA SONGSTER
Keyword(s):  
Local Communities ◽  
Snow Leopard ◽  
Recent Past ◽  
Conservation Science ◽  
The West ◽  
Ideal Case ◽  
Potential Source ◽  
Snow Leopards

AbstractThe snow leopard is a highly charismatic megafauna that elicits admiration, concern and donations from individuals and NGOs in the West. In its home territories, however, it is a threat to local communities' livestock and a potential source of income for its pelt and parts. Conservation and study are further challenged by its range; snow leopards traverse the borders separating China, India and ten other countries with long histories of tension with each other as well as internal political and economic struggles. This transnational animal provides an ideal case study for the consideration of transnational conservation science in the recent past.

How the West Was Won: Woman Suffrage in the Western United States, 1868-1914

2005 ◽  
Vol 39 (1) ◽  
pp. 131
Author(s):  
Melanie Gustafson ◽  
Rebecca J. Mead
Keyword(s):  
United States ◽  
Woman Suffrage ◽  
Western United States ◽  
The West

A comparison of earthquake damage areas as a function of magnitude across the United States

1993 ◽  
Vol 83 (4) ◽  
pp. 1064-1080 ◽  
Author(s):  
G. A. Bollinger ◽  
M. C. Chapman ◽  
M. S. Sibol
Keyword(s):  
United States ◽  
North America ◽  
Ground Motion ◽  
Epicentral Distance ◽  
The United States ◽  
Western United States ◽  
Eastern North America ◽  
Similar Response ◽  
Eastern United States ◽  
The West

Abstract This study investigates the relationship between earthquake magnitude and the size of damage areas in the eastern and western United States. To quantify damage area as a function of moment magnitude (M), 149 MMI VI and VII areas for 109 earthquakes (88 in the western United States, 21 in the eastern United States and Canada) were measured. Regression of isoseismal areas versus M indicated that areas in the East were larger than those in the West, at both intensity levels, by an average 5 × in the M 4.5 to 7.5 range. In terms of radii for circles of equivalent area, these results indicate that damaging ground motion from shocks of the same magnitude extend 2 × the epicentral distance in eastern North America compared to the West. To determine source and site parameters consistent with the above results, response spectral levels for eastern North America were stochastically simulated and compared with response spectral ordinates derived from recorded strong ground motion data in the western United States. Stress-drop values of 200 bars, combined with a surficial 2-km-thick low velocity “sedimentary” layer over rock basement, produced results that are compatible with the intensity observations, i.e., similar response spectral levels in the east at approximately twice their epicentral distance in the western U.S. distance. These results suggest that ground motion modeling in eastern North America may need to incorporate source and site parameters different from those presently in general use. The results are also of importance to eastern U.S. hazard assessments as they require allowance for the larger damage areas in preparedness and mitigation programs.

Mail Routes and the Costs of Expansion, 1866–83

Paper Trails ◽  
2021 ◽  
pp. 75-93
Author(s):  
Cameron Blevins
Keyword(s):  
United States ◽  
Western United States ◽  
Post Office ◽  
Public Infrastructure ◽  
The West ◽  
Agency Model ◽  
Administrative Capacity ◽  
The Us

Chapter 4 examines the transportation of mail in the western United States. During the 1860s and 1870s the Post Office Department contracted with private stagecoach companies to carry the mail on its behalf, allowing it to extend mail routes across the region without establishing its own costly public infrastructure. Government mail contracts effectively subsidized the western stagecoach industry and facilitated the region’s breakneck growth during these decades. But staging companies began to lobby, collude, and bribe their way into exorbitant contracts worth millions of dollars, and by the end of the 1870s the situation had devolved into a full-fledged institutional crisis. This chapter is a story about mismanagement, fraud, and corruption, but it also speaks to the federal government’s lack of centralized administrative capacity. The decentralized agency model may have allowed the US Post to rapidly spread across the West, but this frenetic regional expansion project came with considerable costs.

Grim's Bank, Padworth, Berkshire

Antiquity ◽  
1943 ◽  
Vol 17 (68) ◽  
pp. 188-195
Author(s):  
B. H. St. J. O'Neil
Keyword(s):  
The Other ◽  
Present Writer ◽  
Recent Past ◽  
The West ◽  
The Road ◽  
The North ◽  
Northern Side ◽  
Western Side

The immediate environs of Silchester consist of fields, which are either now under plough or else have been arable for many years in the recent past. Consequently there are few, if any, traces there of the Roman roads which led from the various gates to Dorchester, Speen and Cirencester, Sarum, Winchester, and London. A mile or more to the north and northwest of the Roman town, however, there is a belt of land, which is largely heathland except where trees have been planted. Here there are clear indications of the line of two Roman roads, one from the west gate, west-northwest to Speen and Cirencester, the other from the north gate to Dorchester (Oxon.)The road to Speen (FIG. I) was formerly thought to follow closely the modern road along the northern side of Silchester Common and thence to run along the straight county boundary between Berkshire and Hampshire. In recent years, however, Mr O. G. S. Crawford has shown that the road, instead of following this traditional line, ran west-northwestward to cross the river Kennet near Brimpton Mill. It is traceable as a raised camber or a deep hollow way from Catthaw Lands Copse, about half-a-mile from the west gate of Silchester, to the western side of Hungry Hill. Further west, in Decoy Plantation, and again beyond the road from Padworth Common, i.e. in Keyser's Plantation, it is clearly seen as a broad cambered way (o.s. 641-1. Berkshire XLIV, SE, Hampshire IV, SE). Beyond this point the present writer has not followed it, but Mr Crawford has noted its continuation.

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