Notes on the Survival, Winter Distribution, and Migration Speed of Eastern Mourning Doves

Bird-Banding ◽  
1935 ◽  
Vol 6 (2) ◽  
pp. 61
Author(s):  
Seth H. Low
Ecology ◽  
2013 ◽  
Vol 94 (8) ◽  
pp. 1839-1847 ◽  
Author(s):  
Frank A. La Sorte ◽  
Daniel Fink ◽  
Wesley M. Hochachka ◽  
John P. DeLong ◽  
Steve Kelling

Waterbirds ◽  
2012 ◽  
Vol 35 (1) ◽  
pp. 83-95 ◽  
Author(s):  
Cheri Gratto-Trevor ◽  
R. I. Guy Morrison ◽  
David Mizrahi ◽  
David B. Lank ◽  
Peter Hicklin ◽  
...  

2019 ◽  
Author(s):  
Zahra Allahyari ◽  
Shayan Gholizadeh ◽  
Henry H. Chung ◽  
Luis F. Delgadillo ◽  
Thomas R. Gaborski

ABSTRACTPorous membranes are ubiquitous in cell co-culture and tissue-on-a-chip studies. These materials are predominantly chosen for their semi-permeable and size exclusion properties to restrict or permit transmigration and cell-cell communication. However, previous studies have shown pore size, spacing and orientation affect cell behavior including extracellular matrix production and migration. The mechanism behind this behavior is not fully understood. In this study, we fabricated micropatterned non-fouling polyethylene glycol (PEG) islands to mimic pores in order to decouple the effect of surface discontinuity from grip provided by pore wall edges. Similar to porous membranes, we found that the PEG islands hindered fibronectin fibrillogenesis with cells on patterned substrates producing shorter fibrils. Additionally, cell migration speed over micropatterned PEG islands was greater than unpatterned controls, suggesting that disruption of cell-substrate interactions by PEG islands promoted a more dynamic and migratory behavior, similarly to cells migrating on microporous membranes. Preferred cellular directionality during migration was nearly identical between substrates with identically patterned PEG islands and micropores, further confirming disruption of cell-substrate interactions as a common mechanism behind the cellular responses on these substrates. Interestingly, cell spreading and the magnitude of migration speed was significantly greater on porous membranes compared to PEG islands with identical feature size and spacing, suggesting pore edges enhanced cellular grip. These results provide a more complete picture on how porous membranes affect cells which are grown on them in an increasing number of cellular barrier and co-culture studies.


2003 ◽  
Vol 161 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Beata Wojciak-Stothard ◽  
Anne J. Ridley

Shear stress induces endothelial polarization and migration in the direction of flow accompanied by extensive remodeling of the actin cytoskeleton. The GTPases RhoA, Rac1, and Cdc42 are known to regulate cell shape changes through effects on the cytoskeleton and cell adhesion. We show here that all three GTPases become rapidly activated by shear stress, and that each is important for different aspects of the endothelial response. RhoA was activated within 5 min after stimulation with shear stress and led to cell rounding via Rho-kinase. Subsequently, the cells respread and elongated within the direction of shear stress as RhoA activity returned to baseline and Rac1 and Cdc42 reached peak activation. Cell elongation required Rac1 and Cdc42 but not phosphatidylinositide 3-kinases. Cdc42 and PI3Ks were not required to establish shear stress–induced polarity although they contributed to optimal migration speed. Instead, Rho and Rac1 regulated directionality of cell movement. Inhibition of Rho or Rho-kinase did not affect the cell speed but significantly increased cell displacement. Our results show that endothelial cells reorient in response to shear stress by a two-step process involving Rho-induced depolarization, followed by Rho/Rac-mediated polarization and migration in the direction of flow.


1992 ◽  
Vol 1 (2) ◽  
pp. 163-179 ◽  
Author(s):  
K. A. THOMSON ◽  
W. J. INGRAHAM ◽  
M. C. HEALEY ◽  
P. H. LEBLOND ◽  
C. GROOT ◽  
...  

2013 ◽  
Vol 70 (9) ◽  
pp. 1386-1395 ◽  
Author(s):  
Pekka Hyvärinen ◽  
Petra Rodewald

Low survival of stocked fish has been associated with fitness declines of the captive reared fishes because of genetic domestication and unnatural rearing environments. The effects of broodstock origin (wild or captive) or rearing method (standard or enriched) on survival and migration of hatchery-reared Atlantic salmon smolts (Salmo salar) were investigated in the Tornionjoki River using radiotelemetry. Smolts that were reared with enriched methods had a twofold increase in survival (∼38%) compared with smolts that had been reared in a standard hatchery environment (∼19%). Nature-caught smolts had highest survival (∼57%). Smolts from enriched rearing had a higher initial migration speed than fish from standard rearing. Initial migration speed during the first 3 km was positively correlated to survival probability after 290 km for hatchery fish. There was no clear effect of origin on survival or migration speed. The results of this study show that enriching the rearing environment with methods easily applicable to large-scale production promotes smolt survival and migration speed during river migration, which is imperative for stocking success.


2019 ◽  
Vol 69 (11-12) ◽  
pp. 1273-1285 ◽  
Author(s):  
Laura Brakenhoff ◽  
Gerben Ruessink ◽  
Maarten van der Vegt

Abstract Saw-tooth bars are shore-oblique sand bars that are found along most ebb-tidal deltas of the Frisian Wadden Islands. Although they might significantly affect sediment transport pathways and volumes on the deltas, their general characteristics and dynamics are largely unknown. The main aim of this paper is to determine the typical saw-tooth bar heights, wave lengths, widths, orientations, migration rates and depths of occurrence. To this end, we analysed bathymetries from the Dutch and German Frisian Wadden Islands between 1970 and 2015. Bar heights range between 0.5 and 2 m, and wave lengths range between 300 and 900 m, with an average of 670 m, and the bar crests have a down contour orientation of approximately 25°. The bars are between 800 and 2200 m wide. Saw-tooth bars are located at depths from 3 to 12 m, depending on the slope of the area. Migration speeds of up to 112 m/year were found, using a spatial correlation method. Bar height and migration speed are positively linearly correlated, as well as bar wave length and bar width, bar height and the orientation of the depth contours and migration speed and the orientation of the area. The derived characteristics are compared to those of other bar types to evaluate hypotheses regarding the formation mechanism of the bars.


2018 ◽  
Vol 75 (8) ◽  
pp. 1177-1184 ◽  
Author(s):  
Riina Huusko ◽  
Pekka Hyvärinen ◽  
Mikko Jaukkuri ◽  
Aki Mäki-Petäys ◽  
Panu Orell ◽  
...  

Connectivity problems in fish migration in regulated rivers have been widely studied, but few studies have rigorously compared parallel migration success between regulated and free-flowing rivers. Here, survival and migration speed of downstream migrating radio-tagged Atlantic salmon (Salmo salar) smolts were studied in two large neighboring rivers in the northern Baltic Sea area: one without and one with dams. Both rivers have a free-flowing upper section, where the survival and migration speed of salmon smolts were similar. Survival along the lower section of the free-flowing river was about six times higher than in the lower part of the regulated river with five hydropower plants. Migration speed of smolts was also significantly faster in the river without dams. These severe problems in downstream connectivity in the regulated river pose challenging tasks for restoration of salmon populations.


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