Will reconnecting ecosystems allow long-distance mammal migrations to resume? A case study of a zebra Equus burchelli migration in Botswana

AbstractTerrestrial wildlife migrations, once common, are now rare because of ecosystem fragmentation and uncontrolled hunting. Botswana historically contained migratory populations of many species but habitat fragmentation, especially by fences, has decreased the number and size of many of these populations. During a study investigating herbivore movement patterns in north-west Botswana we recorded a long-distance zebra Equus burchelli antiquorum migration between the Okavango Delta and Makgadikgadi grasslands, a round-trip distance of 588 km; 55% of 11 animals collared in the south-eastern peripheral delta made this journey. This was unexpected as, between 1968 and 2004, the migration could not have followed its present course because of the bisection of the route by a veterinary cordon fence. As little evidence exists to suggest that large-scale movements by medium-sized herbivores can be restored, it is of significant interest that this migration was established to the present highly directed route within 4 years of the fence being removed. The success of wildlife corridors, currently being advocated as the best way to re-establish ecosystem connectivity, relies on animals utilizing novel areas by moving between the connected areas. Our findings suggest that medium-sized herbivores may be able to re-establish migrations relatively quickly once physical barriers have been removed and that the success of future system linkages could be increased by utilizing past migratory routes.

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Formation and Land-Use History of Celtic Fields in North-West Europe – an Interdisciplinary Case Study at Zeijen, the Netherlands

European Journal of Archaeology ◽

10.1179/eja.2003.6.2.141 ◽

2003 ◽

Vol 6 (2) ◽

pp. 141-173 ◽

Cited By ~ 8

Author(s):

Theo Spek ◽

Willy Groenman-van Waateringe ◽

Maja Kooistra ◽

Lideweij Bakker

Keyword(s):

Land Use ◽

The Netherlands ◽

Iron Age ◽

Large Scale ◽

Roman Period ◽

Soil Tillage ◽

North West ◽

Late Iron Age ◽

History Of

Celtic field research has so far been strongly focused on prospection and mapping. As a result of this there is a serious lack of knowledge of formation and land-use processes of these fields. This article describes a methodological case study in The Netherlands that may be applied to other European Celtic fields in the future. By interdisciplinary use of pedological, palynological and micromorphological research methods the authors were able to discern five development stages in the history of the field, dating from the late Bronze Age to the early Roman Period. There are strong indications that the earthen ridges, very typical for Celtic fields in the sandy landscapes of north-west Europe, were only formed in the later stages of Celtic field agriculture (late Iron Age and early Roman period). They were the result of a determined raising of the surface by large-scale transportation of soil material from the surroundings of the fields. Mainly the ridges were intensively cultivated and manured in the later stages of Celtic field cultivation. In the late Iron Age a remarkable shift in Celtic field agriculture took place from an extensive system with long fallow periods, a low level of manuring and extensive soil tillage to a more intensive system with shorter fallow periods, a more intensive soil tillage and a higher manuring intensity. There are also strong indications that rye (Secale cereale) was the main crop in the final stage of Celtic field agriculture.

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Review of periodical articles

Urban History ◽

10.1017/s096392681800007x ◽

2018 ◽

Vol 45 (2) ◽

pp. 351-374

Author(s):

FREDERICK BUYLAERT ◽

GERRIT VERHOEVEN ◽

TIM VERLAAN ◽

REINOUD VERMOESEN

Keyword(s):

Urban Development ◽

Fifteenth Century ◽

Side Effect ◽

Valuable Contribution ◽

Long Distance ◽

North West ◽

Medieval Europe ◽

Urban Settlements ◽

Louis The Pious

Historians are held hostage by the sources that are available to them, and for that reason, the historiography of medieval towns is dominated by research on thirteenth-, fourteenth- or fifteenth-century case-studies. In preceding centuries, literacy was largely the monopoly of ecclesiastical milieus, who were often hostile or simply not interested in describing the urban settlements which then emerged all over Europe. An interesting exception, however, is the Breton town of Redon, which took shape around an abbey that was established in 832 with support of the Carolingian Emperor Louis the Pious. By navigating the unusually extensive set of Carolingian cartularies of this abbey, as well as the available cartographic and archaeological evidence, Julien Bachelier has developed an incisive sketch of the development of a town in the shadow of the Carolingian abbey in the eleventh and twelfth centuries (‘Une ville abbatiale bretonne. Redon du IXe au XIVe siècle’, Histoire Urbaine, 48 (2017), 133–54). This case-study confirms once again that the urbanization of medieval Europe was more than a side-effect of the rebirth of long-distance trade as the canonical Pirenne thesis would have it. The Redon case provides a valuable contribution to the revisionist perspective that stresses the importance of local demand from abbeys, episcopal palaces and castles as a stimulus for urban development (see esp. the seminal work of A. Verhulst, The Rise of Cities in North-West Europe (Cambridge, 1999)).

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I/O performance of the Santos Dumont supercomputer

The International Journal of High Performance Computing Applications ◽

10.1177/1094342019868526 ◽

2019 ◽

Vol 34 (2) ◽

pp. 227-245

Author(s):

Jean Luca Bez ◽

André Ramos Carneiro ◽

Pablo José Pavan ◽

Valéria Soldera Girelli ◽

Francieli Zanon Boito ◽

...

Keyword(s):

Numerical Simulation ◽

Large Scale ◽

Data Access ◽

Performance Differences ◽

Future System ◽

Practical Guidelines ◽

Mpi Implementation ◽

Do So ◽

System Upgrades

In this article, we study the I/O performance of the Santos Dumont supercomputer, since the gap between processing and data access speeds causes many applications to spend a large portion of their execution on I/O operations. For a large-scale expensive supercomputer, it is essential to ensure applications achieve the best I/O performance to promote efficient usage. We monitor a week of the machine’s activity and present a detailed study on the obtained metrics, aiming at providing an understanding of its workload. From experiences with one numerical simulation, we identified large I/O performance differences between the MPI implementations available to users. We investigated the phenomenon and narrowed it down to collective I/O operations with small request sizes. For these, we concluded that the customized MPI implementation by the machine’s vendor (used by more than 20% of the jobs) presents the worst performance. By investigating the issue, we provide information to help improve future MPI-IO collective write implementations and practical guidelines to help users and steer future system upgrades. Finally, we discuss the challenge of describing applications I/O behavior without depending on information from users. That allows for identifying the application’s I/O bottlenecks and proposing ways of improving its I/O performance. We propose a methodology to do so, and use GROMACS, the application with the largest number of jobs in 2017, as a case study.

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Documentation of Complex Environments Using 360° Cameras. The Santa Marta Belltower in Montanaro

Remote Sensing ◽

10.3390/rs13183633 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3633 ◽

Cited By ~ 1

Author(s):

Lorenzo Teppati Losè ◽

Filiberto Chiabrando ◽

Fabio Giulio Tonolo

Keyword(s):

Large Scale ◽

Low Cost ◽

Complex Environments ◽

North West ◽

Processing Strategies ◽

Instruments And Techniques ◽

Simultaneous Location And Mapping ◽

Aerial Systems ◽

Mapping Systems

Low-cost and fast surveying approaches are increasingly being deployed in several domains, including in the field of built heritage documentation. In parallel with mobile mapping systems, uncrewed aerial systems, and simultaneous location and mapping systems, 360° cameras and spherical photogrammetry are research topics attracting significant interest for this kind of application. Although several instruments and techniques can be considered to be consolidated approaches in the documentation processes, the research presented in this manuscript is focused on a series of tests and analyses using 360° cameras for the 3D metric documentation of a complex environment, applied to the case study of a XVIII century belltower in Piemonte region (north-west Italy). Both data acquisition and data processing phases were thoroughly investigated and several processing strategies were planned, carried out, and evaluated. Data derived from consolidated 3D mapping approaches were used as a ground reference to validate the results derived from the spherical photogrammetry approach. The outcomes of this research confirmed, under specific conditions and with a proper setup, the possibility of using 360° images in a Structure from Motion pipeline to meet the expected accuracies of typical architectural large-scale drawings.

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Concentration of a widespread breeding population in a few critically important nonbreeding areas: Migratory connectivity in the Prothonotary Warbler

The Condor ◽

10.1093/condor/duz019 ◽

2019 ◽

Vol 121 (2) ◽

Cited By ~ 12

Author(s):

Christopher M Tonra ◽

Michael T Hallworth ◽

Than J Boves ◽

Jessie Reese ◽

Lesley P Bulluck ◽

...

Keyword(s):

Annual Cycle ◽

Large Scale ◽

Light Level ◽

Breeding Population ◽

Migratory Bird ◽

Migratory Connectivity ◽

Long Distance ◽

Breeding Range ◽

Migratory Routes ◽

Prothonotary Warbler

Abstract One of the greatest challenges to informed conservation of migratory animals is elucidating spatiotemporal variation in distributions. Without such information, it is impossible to understand full-annual-cycle ecology and effectively implement conservation actions that address where and when populations are most limited. We deployed and recovered light-level geolocators (n = 34) at 6 breeding sites in North America across the breeding range of a declining long-distance migratory bird, the Prothonotary Warbler (Protonotaria citrea). We sought to determine migratory routes, stopover location and duration, and the location of overwintering grounds. We found that the species exhibits a large-scale, east‒west split in migratory routes and weak migratory connectivity across its range. Specifically, almost all individuals, regardless of breeding origin, overlapped in their estimated wintering location in northern Colombia, in an area 20% the size of the breeding range. Additionally, most of the individuals across all breeding locations concentrated in well-defined stopover locations in Central America while en route to Colombia. Although error inherent in light-level geolocation cannot be fully ruled out, surprisingly much of the estimated wintering area included inland areas even though the Prothonotary Warbler is considered a specialist on coastal mangroves in winter. Based on these results, conservation efforts directed at very specific nonbreeding geographical areas will potentially have benefits across most of the breeding population. Our findings highlight the importance of using modern technologies to validate assumptions about little-studied portions of a species’ annual cycle, and the need to distribute sampling across its range.

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Distribution and migration of saithe (Pollachius virens) around Iceland inferred from mark-recapture studies

ICES Journal of Marine Science ◽

10.1093/icesjms/fsm076 ◽

2007 ◽

Vol 64 (5) ◽

pp. 1006-1016 ◽

Cited By ~ 18

Author(s):

Hlynur Armannsson ◽

Sigurdur Th. Jonsson ◽

John D. Neilson ◽

Gudrun Marteinsdottir

Keyword(s):

Large Scale ◽

Population Based ◽

Fishing Effort ◽

Stock Structure ◽

Population Parameters ◽

Long Distance ◽

Mark Recapture ◽

History Of ◽

Migratory Routes ◽

And Migration

Abstract Armannsson, H., Jonsson, S. Th., Neilson, J. D., and Marteinsdottir, G. 2007. Distribution and migration of saithe (Pollachius virens) around Iceland inferred from mark-recapture studies. – ICES Journal of Marine Science, 64: 1006–1016. Knowledge of the distribution and migration of populations is necessary to identify and conserve stock components and therefore genetic variability. Compared with other gadoid species, little is known about the life history of saithe (Pollachius virens) (known as pollock in the Northwest Atlantic) or its stock components. About 15 800 saithe were tagged near Iceland from 2000 to 2004 to estimate population parameters, to describe saithe dynamics on the Icelandic shelf, and to monitor long-distance migrations, should they occur. A multiplicative model was used to standardize fishing effort to describe the distribution of the tagged population, based on tag returns from the fishery. Saithe have a high affinity to their tagging area, but move considerably within that area. Because of variability in fishing effort among areas, tagged fish exhibit different area-specific catchabilities. The results also indicate seasonal offshore–inshore migrations during summer and variability in migratory routes among different tagging areas related to affinities to different feeding grounds. This could indicate a more complex stock structure than previously thought. Finally, results to date do not indicate large-scale emigration of saithe from Icelandic fishing grounds.

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Ensuring Australia's competitiveness in the global oil and gas market

The APPEA Journal ◽

10.1071/aj10087 ◽

2011 ◽

Vol 51 (2) ◽

pp. 707

Author(s):

Peter Goode

Keyword(s):

Large Scale ◽

Oil And Gas ◽

Capital Expenditure ◽

Global Scale ◽

North West ◽

The People ◽

Highly Skilled ◽

Working Together ◽

Gas Market

There is an estimated $200 billion worth of capital expenditure presently planned for Australian gas projects. These projects provide the potential for $20 billion worth of engineering and maintenance opportunities for Australian companies and an estimated 16,000 ongoing positions in the sector. The scale of these projects has drawn international attention and is increasingly drawing global competition. Australian companies are at risk of the misperception that they don’t have the international know-how or the people to compete for these large-scale projects. We need to ensure that our Australian ingenuity and scale continue to position us as the service provider of choice for construction, project management and maintenance opportunities. Working together with industry, we have shown that we have what it takes to compete on a global scale. We also need to work with government and unions to ensure we have scalable highly-skilled people available to support these projects. This presentation will consider the following case study: Transfield Services delivers services to companies including Woodside Energy, which operates the A$27 billion North West Shelf project, one of the world’s largest LNG production facilities with an output of 16.4 million tonnes of LNG a year. While expansion continues, ongoing brownfield project and maintenance services demand the ongoing support of a highly-skilled workforce of up to 1,000 people. This case study explores: innovative service solutions in a resource-scarce environment through access to global resources innovative scheduling of work; and, the challenges of sourcing and retaining highly-skilled people by improving the opportunities for global and domestic employee mobility and investing in training and developing local people.

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A Family With Autosomal-Dominant Progressive Sensorineural Hearing Loss

American Journal of Audiology ◽

10.1044/1059-0889.0501.23 ◽

1996 ◽

Vol 5 (1) ◽

pp. 23-32 ◽

Cited By ~ 3

Author(s):

Chris Halpin ◽

Barbara Herrmann ◽

Margaret Whearty

Keyword(s):

Speech Production ◽

Hearing Aids ◽

Role Models ◽

Speech Intelligibility ◽

Large Scale ◽

Speech Language Pathology ◽

The Family ◽

Patient Will ◽

Language Pathology

The family described in this article provides an unusual opportunity to relate findings from genetic, histological, electrophysiological, psychophysical, and rehabilitative investigation. Although the total number evaluated is large (49), the known, living affected population is smaller (14), and these are spread from age 20 to age 59. As a result, the findings described above are those of a large-scale case study. Clearly, more data will be available through longitudinal study of the individuals documented in the course of this investigation but, given the slow nature of the progression in this disease, such studies will be undertaken after an interval of several years. The general picture presented to the audiologist who must rehabilitate these cases is that of a progressive cochlear degeneration that affects only thresholds at first, and then rapidly diminishes speech intelligibility. The expected result is that, after normal language development, the patient may accept hearing aids well, encouraged by the support of the family. Performance and satisfaction with the hearing aids is good, until the onset of the speech intelligibility loss, at which time the patient will encounter serious difficulties and may reject hearing aids as unhelpful. As the histological and electrophysiological results indicate, however, the eighth nerve remains viable, especially in the younger affected members, and success with cochlear implantation may be expected. Audiologic counseling efforts are aided by the presence of role models and support from the other affected members of the family. Speech-language pathology services were not considered important by the members of this family since their speech production developed normally and has remained very good. Self-correction of speech was supported by hearing aids and cochlear implants (Case 5’s speech production was documented in Perkell, Lane, Svirsky, & Webster, 1992). These patients received genetic counseling and, due to the high penetrance of the disease, exhibited serious concerns regarding future generations and the hope of a cure.

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