scholarly journals Comparing fall migration of three Catharus species using a radio-telemetry network

2020 ◽  
Vol 7 (1) ◽  
pp. 1-8
Author(s):  
Camille Bégin Marchand ◽  
André Desrochers ◽  
Junior A. Tremblay ◽  
Pascal Côté
Keyword(s):  
Small Area ◽  
Radio Telemetry ◽  
Southeastern United States ◽  
The Other ◽  
Monitoring Networks ◽  
Migration Routes ◽  
Catharus Ustulatus ◽  
Swainson’S Thrush ◽  
Catharus Bicknelli ◽  
Bicknell's Thrush

AbstractMigration routes vary greatly among small passerine species and populations. It is now possible to determine the routes over great distances and long periods of time with emerging monitoring networks. We tracked individual Swainson’s Thrush (Catharus ustulatus), Bicknell’s Thrush (Catharus bicknelli) and Gray-cheeked Thrush (Catharus minimus) in northeastern Quebec and compared their migration routes and paces across an array of radio-telelemetry stations in North America. Swainson’s Thrush migrated further inland than the other two species. Individuals from all three species slowed their migration pace in the southeastern United States, and Swainson’s Thrush was more likely to stopover than Bicknell’s Thrush. Although individuals were tagged in a small area within or close to their breeding range, the results document the variability of migration routes between species with similar ecological characteristics and provide detailed material to be used for migration studies with broader taxonomic or ecological scope.

scholarly journals Regional patterns of habitat use by a threatened forest bird, the Bicknell’s Thrush (Catharus bicknelli), in Quebec

2016 ◽  
Vol 94 (4) ◽  
pp. 301-309 ◽  
Author(s):  
Yves Aubry ◽  
André Desrochers ◽  
Gilles Seutin
Keyword(s):  
Habitat Use ◽  
Threatened Species ◽  
Spatial Scales ◽  
High Elevation ◽  
Catharus Ustulatus ◽  
Regional Patterns ◽  
Breeding Range ◽  
Catharus Bicknelli ◽  
Potential Competitor ◽  
Bicknell's Thrush

Conservation of threatened species often uses habitat models to inform management of habitat and populations. We examined habitat use by Bicknell’s Thrush (Catharus bicknelli (Ridgway, 1882)), a federally “Threatened” species, in two Appalachian regions, shaped by forestry activities, of southern Quebec. Within its breeding range, the species inhabits mountain tops and forests subjected to various logging activities. We assessed the role of vegetation and topography at two spatial scales, as well as spatial relationships with Swainson’s Thrush (Catharus ustulatus (Nuttall, 1840)), identified as a potential competitor by some authors. In both regions, Bicknell’s Thrushes were most likely to be reported at high elevations, in forest stands with high tree stem densities that underwent little or no stem reduction from forestry activities. Swainson’s Thrushes were present at all sites were Bicknell’s Thrushes were reported. These results are consistent with findings from studies in northeastern parts of its breeding range. We conclude that forest-stand thinning should be kept to a minimum throughout the high-elevation nesting habitat of Bicknell’s Thrush.

scholarly journals Spatial structure in migration routes maintained despite regional convergence among eastern populations of Swainson’s Thrushes

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Camille Bégin-Marchand ◽  
André Desrochers ◽  
Philip D. Taylor ◽  
Junior A. Tremblay ◽  
Lucas Berrigan ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Spatial Structure ◽  
Radio Telemetry ◽  
Spatial Scales ◽  
Regional Convergence ◽  
Migratory Connectivity ◽  
Migration Routes ◽  
Eastern Canada ◽  
Swainson’S Thrush ◽  
Migratory Movements

Abstract Background Migratory connectivity links the different populations across the full cycle and across the species range and may lead to differences in survival among populations. Studies on spatial and temporal migratory connectivity along migration routes are rare, especially for small migratory animals. Methods We used an automated radio-telemetry array to assess migratory connectivity en route and between early and later stages of the fall migration of the eastern populations of Swainson’s Thrush, and to assess the variation of migration pace between consecutive detection from the different receiving stations along the migratory journey. We tracked 241 individuals from across eastern Canada to determine if populations were mixing around the Gulf of Mexico. We also tested the influence of tagging longitude, latitude and age on migration pace. Results Migration routes varied and converged towards the northeast coast of the Gulf of Mexico, but in this region, populations maintained finer-scale spatial structure. Migration pace increased as birds progressed south, independent of age and tagging site. Conclusions We showed that for songbirds, migratory connectivity can be maintained at fine spatial scales despite the regional convergence of populations, highlighting the importance of detailed spatial tracking for identification of population specific migration routes. Overall, our study provides a portrait of migratory movements of eastern Swainson’s Thrush and a framework for understanding spatial structure in migration routes for other species.

Response of Bicknell’s Thrush (Catharus bicknelli) to boreal silviculture and forest stand edges: a radio-tracking study

2011 ◽  
Vol 89 (6) ◽  
pp. 474-482 ◽  
Author(s):  
Yves Aubry ◽  
André Desrochers ◽  
Gilles Seutin
Keyword(s):  
Land Use Planning ◽  
Management Practices ◽  
Radio Telemetry ◽  
Abies Balsamea ◽  
Balsam Fir ◽  
Home Ranges ◽  
Precommercial Thinning ◽  
Clear Cutting ◽  
Catharus Bicknelli ◽  
Bicknell's Thrush

Society and regulatory regimes require that biodiversity conservation, and especially the protection of threatened species, be integrated into land-use planning and management. Bicknell’s Thrush ( Catharus bicknelli (Ridgway, 1882)) is an at-risk species breeding in montane balsam fir ( Abies balsamea (L.) P. Mill.) dominated areas of northeastern North America. We monitored 34 individual Bicknell’s Thrushes by radio telemetry in southern Quebec to examine the size, location, and habitat composition of their home ranges in areas where clear-cutting and precommercial thinning occurred. Home ranges of Bicknell’s Thrush comprised more dense balsam fir stands and fewer thinned stands than available. Within home ranges, thrushes were found more frequently in unthinned balsam fir stands than in thinned stands, and they did not avoid edges. In fact, they were found disproportionately near edges of recently thinned stands. We conclude that Bicknell’s Thrushes may coexist with forest management practices that maintain a landscape mosaic dominated by dense balsam fir patches interspersed with thinned stands.

scholarly journals Resource Selection by Juvenile Swainson's Thrushes During the Postfledging Period

The Condor ◽  
2005 ◽  
Vol 107 (2) ◽  
pp. 388-401 ◽  
Author(s):  
Jennifer D. White ◽  
Thomas Gardali ◽  
Frank R. Thompson ◽  
John Faaborg
Keyword(s):  
Habitat Use ◽  
Breeding Season ◽  
Resource Selection ◽  
Radio Telemetry ◽  
Population Level ◽  
Breeding Habitat ◽  
Resource Base ◽  
Catharus Ustulatus ◽  
Habitat Mosaic ◽  
Swainson’S Thrush

Abstract Resource-selection studies of passerine birds during the breeding season have mainly been limited to understanding those factors important to nesting. However, little is known about what resources are selected by juveniles that are no longer dependent on their parents. The postfledging period may be a critical part of the breeding season for independent juveniles because they must avoid predators and learn to forage on a changing resource base. We used radio-telemetry to study postfledging habitat use and resource selection of juvenile Swainson's Thrushes (Catharus ustulatus) in coastal California from 2000 to 2002. We generated population-level contours (50% and 95% fixed-kernel) to describe habitat use by independent juveniles, and we determined juvenile resource selection by comparing vegetation characteristics at sites used by juveniles versus random sites. Juvenile Swainson's Thrushes used mixed-hardwood forest and coastal scrub during the postfledging period as well as riparian vegetation used by nesting adults. The most parsimonious predictors of resource selection were fruit abundance variables, suggesting that postfledging habitat selection by the Swainson's Thrush is best explained by the optimal-foraging hypothesis. We suggest that juvenile thrushes can track food resources in a habitat mosaic and use vegetation types distinct from what is traditionally considered Swainson's Thrush breeding habitat. Selección de Recursos por Juveniles de Cathatus ustulatus Durante el Periodo de Emancipación Resumen. Los estudios de selección de recursos en aves paserinas durante la estación reproductiva, se han centrado principalmente en entender los factores importantes para la anidación. Sin embargo, se sabe poco acerca de los recursos seleccionados por los juveniles que ya no dependen de sus padres. Para los juveniles independientes, el periodo de emancipación podría ser una parte crítica de la estación reproductiva en la que deben evitar depredadores y aprender a forrajear sobre una base de recursos fluctuante. Por medio de telemetría, estudiamos el uso de hábitat y selección de recursos en juveniles del zorzal Catharus ustulatus en la costa de California entre los años 2000 y 2002. A nivel de población, generamos polígonos (de 50% y 95% de “kernel” fijo) para describir la utilización de hábitat por juveniles independientes, y para determinar la selección de recursos comparamos las características de la vegetación de los sitios utilizados con la de sitios aleatorios pareados. Los juveniles utilizaron bosques mixtos y matorral costero durante el periodo de emancipación, así como la vegetación riparia utilizada por adultos nidificantes. Las variables con las predicciones más parsimoniosas del uso de recursos fueron las relacionadas con la abundancia de frutos, lo que sugiere que la selección de hábitat de emancipación por C. ustulatus es explicada en mejores términos por la hipótesis de forrajeo óptimo. Sugerimos que los zorzales juveniles pueden encontrar recursos alimenticios en mosaicos de hábitat y usar tipos de vegetación distintos a los que tradicionalmente se consideran como hábitat de anidación.

BREEDING DESTINATIONS AND SPRING MIGRATION PATTERNS OF SWAINSON'S THRUSH (CATHARUS USTULATUS) AT A COSTA RICAN STOPOVER SITE

The Auk ◽  
2008 ◽  
Vol 125 (1) ◽  
pp. 95-104 ◽  
Author(s):  
SCOTT WILSON ◽  
KEITH A. HOBSON ◽  
DOUGLAS M. COLLISTER ◽  
AMY G. WILSON
Keyword(s):  
Costa Rican ◽  
Spring Migration ◽  
Catharus Ustulatus ◽  
Stopover Site ◽  
Migration Patterns ◽  
Swainson’S Thrush

scholarly journals V.—Note on an Undescribed Area of Lower Greensand or Vectian in Dorset

1891 ◽  
Vol 8 (10) ◽  
pp. 456-458 ◽  
Author(s):  
A. J. Jukes-Browne
Keyword(s):  
Lower Cretaceous ◽  
Small Area ◽  
Upper Cretaceous ◽  
The Other ◽  
Present Communication ◽  
The Subject ◽  
Geological Magazine

Until recently no outcrop of the Vectian or Lower Greensand was known to occur between Lulworth on the coast of Dorset and the neighbourhood of Devizes in Wiltshire. It was supposed that, with the exception of a small area of Wealden in the Vale of Wardour, the whole of the Lower Cretaceous Series in Dorset and South Wilts was concealed and buried beneath the overlapping Upper Cretaceous strata. A recent examination of this district however has revealed two areas where the Vectian sands emerge from beneath the Gault. One of these has already been indicated in the pages of the Geological Magazine; the other is the subject of the present communication.

Nomad Migration in Central Asia

2007 ◽  
Author(s):  
KAZIM ABDULLAEV
Keyword(s):  
Central Asia ◽  
Second Century ◽  
The Other ◽  
Cultural Identities ◽  
Migration Routes ◽  
Central Asian ◽  
History Of ◽  
And Migration

This chapter examines the ethnic and cultural identities and migration routes of nomadic tribes in Central Asia. It explains that the migration of Central Asian nomads, particularly into Transoxiana, can be divided into two categories. One is the long trans-regional route ascribable to the migration of the Yuezhi tribe from the valley of Gansu to the territory north of the Oxus River, and the other is the local migration attributed to the tribes such as the Dahae, Sakaraules, and Appasiakes. The chapter suggests that the events which determined nomad migration are connected with the history of the northern and western borders of Han China in the second century BC.

Neighbor Topology for Dynamic Plane Coverage in Swarm Leading Control

2012 ◽  
Vol 3 (1) ◽  
pp. 59-75
Author(s):  
Keitaro Naruse ◽  
Tatsuya Sato
Keyword(s):  
Small Area ◽  
Control Method ◽  
The Other ◽  
Large Field ◽  
Multiple Robots ◽  
Coverage Problem ◽  
Coverage Area ◽  
Fixed Distance ◽  
Equal Density ◽  
Dynamic Plane

The objective of this paper is to solve the dynamic plane coverage problem by the movement of multiple robots, for example, sprinkling water to a large field by several vehicles or aircrafts, in which all of the points in the field should be covered by the robots in an almost equal density. One of the ways to solve it is the swarm leading control method, in which one of the robots, called a target, moves along a path in the field, and all the other robots move around the target with a fixed distance. In the process, the topology of the robots affects to the efficiency of the dynamic plane coverage problem. If the topology is a tight one, the swarm can be stable but the coverage area can be limited in a small area. On the other hand, if it is a loose one, an opposite thing can be happened. In this paper, the relation between the topology and the efficiency is discussed numerically.

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