Winter Survival Rates of American Woodcock in South Central Louisiana

2000 ◽  
Vol 64 (4) ◽  
pp. 933 ◽  
Author(s):  
Richard M. Pace
Keyword(s):  
Survival Rates ◽  
Winter Survival ◽  
American Woodcock ◽  
South Central

Influence of Planting Stock Clove Size, Nitrogen Rate, and Planting Method on Elephant Garlic Production

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 517f-518
Author(s):  
Jeanine M. Davis
Keyword(s):  
Survival Rates ◽  
Ground Level ◽  
Winter Survival ◽  
Nitrogen Rate ◽  
Planting Stock ◽  
Mild Winter ◽  
Allium Ampeloprasum ◽  
Planting Methods ◽  
Planting Method ◽  
Nitrogen Rates

To produce large elephant garlic (Allium ampeloprasum L.) bulbs in the southeastern United States, stock cloves must be planted in the fall. During extremely cold winters, however, winter survival rates can be very low. A 2-year study was undertaken to examine practices to increase winter survival rates. Two clove sizes (≤20 g or >20 g), three nitrogen rates (112, 224, and 336 kg/ha), and three planting methods (flat, mulched, and hilled) were tested in a RCB design with four replications. For all planting methods, cloves were set in a shallow trench and covered with soil to ground level. This was also the flat treatment. For the mulched treatment, 7 cm of straw was spread on top. For the hilled treatment, soil was mounded 10 to 15 cm high over the ground level. Cloves were planted in early October and harvested in mid-June. Use of large planting stock cloves increased winter survival rates during the harsh winter, but had no effect during the mild winter. Both years, winter survival was reduced with the flat treatment. Yields of marketable bulbs were 4 to 5 times higher when >20 g cloves were planted than when ≤20 g cloves were used. Nitrogen rate and planting method had no effect on yields. The >20 g cloves also produced larger bulbs than the smaller cloves. Of the three planting methods, the flat treatment produced the smallest bulbs. Bulbs were much larger following the mild winter than the harsh winter.

Factors Affecting Winter Survival of Johnsongrass (Sorghum halepense) Rhizomes

1991 ◽  
Vol 5 (1) ◽  
pp. 108-110 ◽  
Author(s):  
Robert G. Hartzler ◽  
Art Gover ◽  
Joanne Stellingwerf
Keyword(s):  
Survival Rates ◽  
Winter Survival ◽  
Sorghum Halepense ◽  
Factors Affecting ◽  
Rhizome Biomass ◽  
Depth Of Burial

There were no differences in johnsongrass rhizome winter survival at central and southeastern locations in Pennsylvania in 1988 or 1989. At a 6-cm depth of burial, survival rates of 5 and 25% were found for rhizome segments 7.5 and 15.0 cm in length, respectively. Survival rates for rhizomes buried 25 cm averaged 86%, with no difference in survival between rhizome lengths. The majority of rhizome biomass produced by the biotype used in these studies was found at soil depths allowing a high percentage of survival.

Winter Survival and Territory Acquisition in a Northern Population of Black-Capped Chickadees

The Auk ◽  
1988 ◽  
Vol 105 (4) ◽  
pp. 727-736 ◽  
Author(s):  
André Desrochers ◽  
Susan J. Hannon ◽  
Kelly E. Nordin
Keyword(s):  
Survival Rates ◽  
Early Spring ◽  
Control Area ◽  
Winter Survival ◽  
Food Supplementation ◽  
First Year ◽  
Differential Survival ◽  
Northern Population ◽  
Parus Atricapillus ◽  
Lower Ranking

Abstract We assessed the effects of winter food supplementation on differential survival between sex, age and dominance classes, and the effects of feeding and territorial defense on breeding density in a northern population of Black-capped Chickadees (Parus atricapillus). Survival rates were higher in a food-supplemented area than in a control area, which suggests that food abundance limited winter survival. Survival was greater among males than lower-ranking females in 1 of 2 years, and greater in dominants than in subordinates, within sex and age classes. Survival of adults and first-year birds, however, did not differ significantly. In the 2 years of this study, a sharp decline of population size occurred at the onset of territoriality in spring. Birds that disappeared in spring were mainly subordinates of each sex. Breeding densities in control and feeder areas were similar in the two years. Eight of 14 territorial birds removed in 2 years were replaced, implying that a nonbreeding surplus was present in early spring.

Determination of optimal sowing dates and densities of winter wheat under Quebec growing conditions

2019 ◽  
Vol 99 (2) ◽  
pp. 221-231 ◽  
Author(s):  
Francis Allard ◽  
Anne Vanasse ◽  
Denis Pageau ◽  
Gilles Tremblay ◽  
Julie Durand ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Survival Rates ◽  
Sowing Date ◽  
Winter Survival ◽  
Seeding Density ◽  
Good Survival ◽  
First Year ◽  
Sowing Dates ◽  
Yield Gain ◽  
Growing Conditions

The objective of this project was to determine the optimal sowing dates and densities for winter wheat to increase winter survival and yield under Quebec growing conditions. The trials were carried out from 2014 to 2016 at four sites, representing three cereal production zones (zones 1, 2, and 3). Three cultivars were assessed using four sowing dates and four seeding densities (250, 350, 450, and 550 seeds m−2). In the first year, the wheat at two of the four sites survived (82%–100%), and in the second year, all the sites showed good survival rates (69%–99%). In zone 2, winter survival was higher for the early sowing dates compared with later dates. Sowing date and seeding density had no effect on survival in zones 1 and 3. Maximum yields were attained with sowing dates from mid- to late September in zone 1; from early to mid-September in zone 2; and from mid-August to mid-September in zone 3. An increase in seeding density from 250 to 550 seeds m−2 led to an average yield gain of 9% in zones 2 and 3, but no gain in zone 1. Winter survival rates and yield differ between cultivars.

Winter survival and habitat use of orphaned and non-orphaned moose calves in southern Quebec

1988 ◽  
Vol 66 (4) ◽  
pp. 919-924 ◽  
Author(s):  
Hélène Jolicoeur ◽  
Michel Crête
Keyword(s):  
Habitat Selection ◽  
Home Range ◽  
Habitat Use ◽  
Survival Rates ◽  
Winter Survival ◽  
Tree Cover ◽  
Home Ranges ◽  
Severe Winter ◽  
Browse Species ◽  
Forage Utilization

Survival, movements, home ranges, habitat selection, and diets of 13 orphaned and 13 non-orphaned moose calves were compared during their first winter. Survival of four other calves that became separated from their mothers was also monitored. The study took place during three winters between December 1978 and April 1983. Overall, winter survival rates between the two groups did not differ. When mortality did occur, it involved solitary (orphaned and separated) calves during a severe winter. Movements and home-range sizes of the two groups were also similar. Biomass of forage on winter sites, forage utilization, and importance of tree cover were similar on sites chosen by orphaned and non-orphaned calves. Minor differences were observed in the order of preference of browse species. Five solitary calves were involved in either temporary or permanent associations with other moose.

scholarly journals Propagation Time Affects Winter Survival and Finishing Date for Ornamental Grasses

2002 ◽  
Vol 20 (4) ◽  
pp. 201-203 ◽  
Author(s):  
Bruce A. Cunliffe ◽  
Mary Hockenberry Meyer
Keyword(s):  
Survival Rates ◽  
Winter Survival ◽  
Schizachyrium Scoparium ◽  
Miscanthus Sinensis ◽  
Propagation Time ◽  
Little Bluestem ◽  
Ornamental Grasses ◽  
One Year

Abstract Five grasses: little bluestem, Schizachyrium scoparium (Michx.) Nash; prairie dropseed, Sporobolus heterolepis (A. Gray) A. Gray; feather reedgrass, Calamagrostis x acutiflora (Schrad.) DC. ‘Karl Foerster’; redflame miscanthus, Miscanthus Anderss. ‘Purpurascens’; and variegated Japanese silvergrass, Miscanthus sinensis Anderss. ‘Variegatus’; were propagated in fall and spring by plugs or field divisions into 480 ml (4 in round), 2.7 liter (#1), or 6.2 liter (#2) nursery containers. Plants were evaluated for finish date and winter survival. Three fall handled species consistently finished as a salable plant within one year: Schizachyrium scoparium plugs, Calamagrostis xacutiflora ‘Karl Foerster’ divisions, and Miscanthus ‘Purpurascens’ divisions. Sporobolus heterolepis and Miscanthus sinensis ‘Variegatus’ grew faster and finished with significantly higher survival rates from spring divisions. Spring planted plugs of S. heterolepis and S. scoparium finished within 9 weeks. The two smaller container sizes finished significantly ahead of the larger size.

scholarly journals Golden Eagle Abundance in Alaska: Migration Counts and Movement Data Generate a Conservative Population Estimate

2021 ◽  
Author(s):  
Travis L. Booms ◽  
Neil A. Paprocki ◽  
Joseph M. Eisaguirre ◽  
Chris P. Barger ◽  
Stephen B. Lewis ◽  
...  
Keyword(s):  
Management Strategies ◽  
Survival Rates ◽  
Credible Interval ◽  
Population Estimate ◽  
Gps Tracking ◽  
Golden Eagle ◽  
Movement Data ◽  
South Central ◽  
Golden Eagles ◽  
Migration Corridor

ABSTRACT Estimating species density and abundance is challenging but important for establishing conservation and management strategies. Significant progress has been made toward estimating Golden Eagle (Aquila chrysaetos) abundance in the conterminous United States of America (USA) but much less is known about eagle abundance in Alaska. Here, we paired migration count and GPS-tracking data collected near Gunsight Mountain, Alaska, in a Bayesian framework to estimate the number of Golden Eagles in south-central Alaska. We estimated 1204 (95% credible interval: 866, 1526) potentially breeding (≥4 yr old) Golden Eagles annually moved through the Gunsight Mountain migration corridor and summered over an area of 150,325 km2 in south-central Alaska, equating to a density of 0.80 potentially breeding eagles/100 km2. By extrapolating across the species' nesting range in Alaska (1,180,489 km2) and incorporating published productivity and age-specific survival rates for eagles <4 yr old into our hierarchical model, we estimated 12,717 (95% credible interval: 9043, 16,349) Golden Eagles of all ages occur in Alaska, annually. We propose this as a conservative statewide population estimate because we used methods that likely underestimated population size. Even so, our estimate is three to five times larger than previous estimates and likely represents about one quarter of the USA's population.

scholarly journals Resistance Development to Diflubenzuron and Bacillus Thuringiensis Subsp. Israelensis of Culex Pipiens f. Pipiens and Culex Pipiens f. Molestus (Diptera: Culicidae) and its Effects on Their Winter Survival

2020 ◽  
Author(s):  
Charalampos Ioannou ◽  
Christos Hadjichristodoulou ◽  
Maria A. Kyritsi ◽  
Nikos T. Papadopoulos
Keyword(s):  
Bacillus Thuringiensis ◽  
Culex Pipiens ◽  
Survival Rates ◽  
Larval Survival ◽  
Winter Survival ◽  
World Health ◽  
Winter Period ◽  
Fitness Costs ◽  
Resistance Development ◽  
High Dependency

Abstract Background: The Culex pipiens mosquito consists of two forms named pipiens and molestus that exhibit substantial differences in their biology including overwintering behavior. Diflubenzuron (DFB) and Bacillus thuringiensis subsp. israelensis (Bti) are among the most widely used larvicides for controlling Cx. pipiens populations. The high dependency on these two larvicides, pose major concerns for resistance development. The evolution and stability of resistance to insecticides has been associated with fitness costs that may be manifested under stressful conditions such as the winter period. The aim of the present study was to explore the resistance development of pipiens and molestus forms to both larvicides and its potential fitness costs on their winter survival.Methods: Colonies of both forms of Cx. pipiens were established from the same area. Following the World Health Organization protocols (WHO), the efficacy of both larvicides was determined for each mosquito population. Then, larvae from each form were selected for three successive generations by applying fixed doses corresponding to IE80 (IE: Inhibition of adult Emergence) and LC80 (LC: Lethal Concentration) for DFB and Bti respectively. At the end of this process, the resistance levels and the winter survival of the selected populations relative to controls (colonies that received no selection) were determined.Results: Contrary to Bti, selection with DFB induced different levels of resistance between the two forms of Cx. pipiens. The selected populations of Cx. pipiens f. molestus to both larvicides exhibited a high fitness cost in terms of reduced winter larval survival rates relative to control. Moreover, the obtained adults of the Bti selected population experienced significantly shorter lifespan compared to control and DFB selected population. On the other hand, selection with both DFB and Bti had no apparent effects on Cx. pipiens f. pipiens female winter survival rates relative to control. Furthermore, the reproductive parameters and the longevity of the overwintered females were similar between the selected populations and the control. Conclusions: Our findings are expected to contribute on the better understanding of the resistance development and evolution of the two forms of Cx. pipiens to DFB and Bti allowing the adoption of appropriate resistance management strategies.

scholarly journals Cold-Triggered Induction of ROS- and Raffinose Metabolism in Freezing-Sensitive Taproot Tissue of Sugar Beet

2021 ◽  
Vol 12 ◽  
Author(s):  
Isabel Keller ◽  
Christina Müdsam ◽  
C. Martins Rodrigues ◽  
Dominik Kischka ◽  
Wolfgang Zierer ◽  
...  
Keyword(s):  
Sugar Beet ◽  
Freezing Tolerance ◽  
Low Temperatures ◽  
Survival Rates ◽  
Protective Role ◽  
Winter Survival ◽  
Temperate Climate ◽  
Freezing Damage ◽  
Anatomy And Physiology ◽  
Freezing Temperatures

Sugar beet (Beta vulgaris subsp. vulgaris) is the exclusive source of sugar in the form of sucrose in temperate climate zones. Sugar beet is grown there as an annual crop from spring to autumn because of the damaging effect of freezing temperatures to taproot tissue. A collection of hybrid and non-hybrid sugar beet cultivars was tested for winter survival rates and freezing tolerance. Three genotypes with either low or high winter survival rates were selected for detailed study of their response to frost. These genotypes differed in the severity of frost injury in a defined inner region in the upper part of the taproot, the so-called pith. We aimed to elucidate genotype- and tissue-dependent molecular processes during freezing and combined analyses of sugar beet anatomy and physiology with transcriptomic and metabolite profiles of leaf and taproot tissues at low temperatures. Freezing temperatures induced strong downregulation of photosynthesis in leaves, generation of reactive oxygen species (ROS), and ROS-related gene expression in taproots. Simultaneously, expression of genes involved in raffinose metabolism, as well as concentrations of raffinose and its intermediates, increased markedly in both leaf and taproot tissue at low temperatures. The accumulation of raffinose in the pith tissue correlated with freezing tolerance of the three genotypes. We discuss a protective role for raffinose and its precursors against freezing damage of sugar beet taproot tissue.

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