scholarly journals Enriching the isotopic toolbox for migratory connectivity analysis: a new approach for migratory species breeding in remote or unexplored areas

2015 ◽  
Vol 21 (4) ◽  
pp. 416-427 ◽  
Author(s):  
Sasha Pekarsky ◽  
Alon Angert ◽  
Barbara Haese ◽  
Martin Werner ◽  
Keith A. Hobson ◽  
...  
Keyword(s):  
Connectivity Analysis ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
New Approach

Integrating tracking and resight data enables unbiased inferences about migratory connectivity and winter range survival from archival tags

The Condor ◽  
2021 ◽  
Author(s):  
Clark S Rushing ◽  
Aimee M Van Tatenhove ◽  
Andrew Sharp ◽  
Viviana Ruiz-Gutierrez ◽  
Mary C Freeman ◽  
...  
Keyword(s):  
Transition Probabilities ◽  
Eastern United States ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
Pet Trade ◽  
Winter Range ◽  
Archival Tags ◽  
Breeding Grounds ◽  
Unbiased Estimates ◽  
Further Development

Abstract Archival geolocators have transformed the study of small, migratory organisms but analysis of data from these devices requires bias correction because tags are only recovered from individuals that survive and are re-captured at their tagging location. We show that integrating geolocator recovery data and mark–resight data enables unbiased estimates of both migratory connectivity between breeding and nonbreeding populations and region-specific survival probabilities for wintering locations. Using simulations, we first demonstrate that an integrated Bayesian model returns unbiased estimates of transition probabilities between seasonal ranges. We also used simulations to determine how different sampling designs influence the estimability of transition probabilities. We then parameterized the model with tracking data and mark–resight data from declining Painted Bunting (Passerina ciris) populations breeding in the eastern United States, hypothesized to be threatened by the illegal pet trade in parts of their Caribbean, nonbreeding range. Consistent with this hypothesis, we found that male buntings wintering in Cuba were 20% less likely to return to the breeding grounds than birds wintering elsewhere in their range. Improving inferences from archival tags through proper data collection and further development of integrated models will advance our understanding of the full annual cycle ecology of migratory species.

scholarly journals Elevational niche-shift migration: Why the degree of elevational change matters for the ecology, evolution, and physiology of migratory birds

The Auk ◽  
2021 ◽  
Author(s):  
Jessie L Williamson ◽  
Christopher C Witt
Keyword(s):  
Partial Pressure ◽  
Bird Species ◽  
Seasonal Migration ◽  
Critical Examination ◽  
Niche Shift ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
Arterial Blood ◽  
Air Density ◽  
Elevational Migration

Abstract Elevational migration can be defined as roundtrip seasonal movement that involves upward and downward shifts in elevation. These shifts incur physiological challenges that are proportional to the degree of elevational change. Larger shifts in elevation correspond to larger shifts in partial pressure of oxygen, air density, temperature, and ultraviolet (UV) exposure. Although most avian examples of elevational migration involve subtle shifts that would have minimal impacts on physiology, shifts of any magnitude have previously been considered under the broad umbrella of “elevational migration”. Here, we consider extreme seasonal elevational movements (≥2,000 m), sufficient to shift the elevational dimension of the eco-climatic niche. Migratory bird populations typically maintain inter-seasonal stability in the temperature, precipitation, and elevational aspects of their climatic niches, a tendency that likely reflects genetic physiological specialization on environmental conditions such as atmospheric pressure. A shift of ≥2,000 m involves a ≥20% change in air density and oxygen partial pressure, sufficient to incur functionally impactful declines in arterial blood-oxygen saturation and require compensatory shifts in respiratory physiology. We refer to this phenomenon as elevational niche-shift migration (ENSM). In this review, we analyzed >4 million occurrence records to identify 105 populations, representing 92 bird species, that undergo complete or partial ENSM. We identified key ecological and evolutionary questions regarding the causes and consequences of ENSM. Our synthesis reveals that ENSM has evolved independently in at least 29 avian families spanning 10 orders. Nonetheless, ENSM is rare relative to other forms of seasonal migration, consistent with the general tendency of seasonal niche conservatism by migratory species and evolutionarily conserved elevational range limits. For many migratory species and populations, within-species patterns of migratory connectivity are not sufficiently understood to determine ENSM status. ENSM is distinguished by its scale within the broader phenomenon of elevational migration. Critical examination of ENSM illustrates fundamental constraints on the ecology and evolution of migration systems, topographical influences on geographic patterns of migratory connectivity, and the remarkable metabolic flexibility of certain bird species that allows them to occupy disparate elevations across different seasons.

scholarly journals Genomes to space stations: the need for the integrative study of migration for avian conservation

2018 ◽  
Vol 14 (2) ◽  
pp. 20170741 ◽  
Author(s):  
Adam M. Fudickar ◽  
Ellen D. Ketterson
Keyword(s):  
Field Studies ◽  
Migratory Behaviour ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
Avian Migration ◽  
Weather Patterns ◽  
Migration Data ◽  
Integrative Study ◽  
Genetic Mechanisms ◽  
Radical Transformation

Ongoing changes to global weather patterns and human modifications of the environment have altered the breeding and non-breeding ranges of migratory species, the timing of their migrations, and even whether they continue to migrate at all. Animal movements are arguably one of the most difficult behaviours to study, particularly in smaller birds that migrate tens to thousands of kilometres seasonally, often moving hundreds of kilometres each day. The recent miniaturization of tracking and logging devices has led to a radical transformation in our understanding of avian migratory behaviour and migratory connectivity. While advances in technology have altered the way researchers study migratory behaviour in the field, advances in techniques related to the study of physiological and genetic mechanisms underlying migratory behaviour have rarely been integrated into field studies of tracking. To predict the capacity of migrants to adjust to a changing planet, it is essential that we combine avian migration data with physiological and genetic measurements taken at key time points prior to, during and after migration.

Insights into migratory connectivity and conservation concerns of Red Knots Calidris canutus in the austral Pacific coast of the Americas

2021 ◽  
pp. 1-9
Author(s):  
CAMILA GHERARDI-FUENTES ◽  
JORGE RUIZ ◽  
JUAN G. NAVEDO
Keyword(s):  
Pacific Coast ◽  
Atlantic Coast ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
Essential Information ◽  
Calidris Canutus ◽  
The North ◽  
Migratory Shorebirds ◽  
Daily Rate ◽  
The Pacific

Summary Migratory species rely on several distant sites during the annual cycle which makes their conservation more complex than that of non-migratory species. Even one of the most extensively studied migratory shorebirds - the Red Knot Calidris canutus - is currently ‘Near Threatened’ at the global level. Conflicting observations of migratory routes cast uncertainty on the subspecies classification and migratory connectivity of Red Knots in the Pacific coasts of the Americas. To fill essential information gaps, we present the first detailed population morphometrics of Red Knots during the non-breeding season in the southern Pacific coast, along with resightings of these birds throughout the Americas. We also estimated daily rate of weight gain during fuelling based on body mass at captures and known departure dates. Resightings demonstrate reliance on staging areas in both the Mid-continental and Atlantic flyways during the northward migration, and additionally in the Pacific Flyway during southward migration. In addition to the strong connection with several areas also used by C. c. rufa on the North American Atlantic coast, our results show morphometric differences within the ranges of both C. c. rufa and C. c. roselaari. Given the threats faced by Red Knots, the population in Chiloé Archipelago should be treated as a separate conservation unit within interhemispheric conservation programmes for endangered shorebirds within the Americas.

scholarly journals Population trends inVermivorawarblers are linked to strong migratory connectivity

2018 ◽  
Vol 115 (14) ◽  
pp. E3192-E3200 ◽  
Author(s):  
Gunnar R. Kramer ◽  
David E. Andersen ◽  
David A. Buehler ◽  
Petra B. Wood ◽  
Sean M. Peterson ◽  
...  
Keyword(s):  
Annual Cycle ◽  
Migratory Birds ◽  
Population Trends ◽  
Limiting Factors ◽  
Migratory Connectivity ◽  
Migratory Species ◽  
Vermivora Chrysoptera ◽  
Breeding Populations ◽  
Migratory Songbirds ◽  
Weak Connectivity

Migratory species can experience limiting factors at different locations and during different periods of their annual cycle. In migratory birds, these factors may even occur in different hemispheres. Therefore, identifying the distribution of populations throughout their annual cycle (i.e., migratory connectivity) can reveal the complex ecological and evolutionary relationships that link species and ecosystems across the globe and illuminate where and how limiting factors influence population trends. A growing body of literature continues to identify species that exhibit weak connectivity wherein individuals from distinct breeding areas co-occur during the nonbreeding period. A detailed account of a broadly distributed species exhibiting strong migratory connectivity in which nonbreeding isolation of populations is associated with differential population trends remains undescribed. Here, we present a range-wide assessment of the nonbreeding distribution and migratory connectivity of two broadly dispersed Nearctic-Neotropical migratory songbirds. We used geolocators to track the movements of 70Vermivorawarblers from sites spanning their breeding distribution in eastern North America and identified links between breeding populations and nonbreeding areas. Unlike blue-winged warblers (Vermivora cyanoptera), breeding populations of golden-winged warblers (Vermivora chrysoptera) exhibited strong migratory connectivity, which was associated with historical trends in breeding populations: stable for populations that winter in Central America and declining for those that winter in northern South America.

The O–C diagrams of minor planets − a new approach to modelling the rotation

1999 ◽  
Vol 173 ◽  
pp. 185-188
Author(s):  
Gy. Szabó ◽  
K. Sárneczky ◽  
L.L. Kiss
Keyword(s):  
Error Analysis ◽  
Time Dependence ◽  
Theoretical Work ◽  
Minor Planet ◽  
Minor Planets ◽  
New Approach ◽  
Preliminary Results ◽  
Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Processing Immunoperoxidase Labeled Cell Monolayers and Cryostat Sesctions For Electron Microscopy

1985 ◽  
Vol 43 ◽  
pp. 714-715
Author(s):  
K. Chien ◽  
R. Van de Velde ◽  
I.P. Shintaku ◽  
A.F. Sassoon
Keyword(s):  
Cell Monolayer ◽  
Cell Types ◽  
Surface Antigens ◽  
Immunoperoxidase Method ◽  
Reaction Step ◽  
Hot Plate ◽  
Air Drying ◽  
New Approach ◽  
Cell Monolayers ◽  
Glass Slides

Immunoelectron microscopy of neoplastic lymphoma cells is valuable for precise localization of surface antigens and identification of cell types. We have developed a new approach in which the immunohistochemical staining can be evaluated prior to embedding for EM and desired area subsequently selected for ultrathin sectioning.A freshly prepared lymphoma cell suspension is spun onto polylysine hydrobromide- coated glass slides by cytocentrifugation and immediately fixed without air drying in polylysine paraformaldehyde (PLP) fixative. After rinsing in PBS, slides are stained by a 3-step immunoperoxidase method. Cell monolayer is then fixed in buffered 3% glutaraldehyde prior to DAB reaction. After the DAB reaction step, wet monolayers can be examined under LM for presence of brown reaction product and selected monolayers then processed by routine methods for EM and embedded with the Chien Re-embedding Mold. After the polymerization, the epoxy blocks are easily separated from the glass slides by heatingon a 100°C hot plate for 20 seconds.

TEM study of a biofilm on copper corrosion

1996 ◽  
Vol 54 ◽  
pp. 220-221
Author(s):  
W. A. Chiou ◽  
N. Kohyama ◽  
B. Little ◽  
P. Wagner ◽  
M. Meshii
Keyword(s):  
Marine Bacterium ◽  
Culture Medium ◽  
Copper Alloys ◽  
Pure Copper ◽  
Localized Corrosion ◽  
Natural Seawater ◽  
Copper Corrosion ◽  
New Approach ◽  
The Past ◽  
Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

High resolution at low voltage: A new approach

1989 ◽  
Vol 47 ◽  
pp. 76-77
Author(s):  
Arthur V. Jones
Keyword(s):  
Low Voltage ◽  
Emission Sources ◽  
New Approach ◽  
Design Concepts ◽  
Probe Diameter ◽  
Low Voltage Operation ◽  
Sufficient Intensity ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes ◽  
Immersion Type

With the introduction of field-emission sources and “immersion-type” objective lenses, the resolution obtainable with modern scanning electron microscopes is approaching that obtainable in STEM and TEM-but only with specific types of specimens. Bulk specimens still suffer from the restrictions imposed by internal scattering and the need to be conducting. Advances in coating techniques have largely overcome these problems but for a sizeable body of specimens, the restrictions imposed by coating are unacceptable.For such specimens, low voltage operation, with its low beam penetration and freedom from charging artifacts, is the method of choice.Unfortunately the technical dificulties in producing an electron beam sufficiently small and of sufficient intensity are considerably greater at low beam energies — so much so that a radical reevaluation of convential design concepts is needed.The probe diameter is usually given by

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