Supplemental Food and Laying Date in the European Starling

The Condor ◽  
1993 ◽  
Vol 95 (4) ◽  
pp. 1031-1034 ◽  
Author(s):  
Johnny Karlsson
1987 ◽  
Vol 65 (5) ◽  
pp. 1270-1274 ◽  
Author(s):  
Wesley M. Hochachka ◽  
David A. Boag

Supplemental food was provided to a breeding population of Black-billed Magpies (Pica pica), starting before and after eggs were laid, to determine if and when natural food was limited. The production of fledgling magpies was increased only when supplemental feeding was begun before laying. Laying date was also advanced when supplemental feeding began before laying, but clutch and egg size were not significantly changed. Because the two feeding treatments were conducted in different years, we cannot conclude whether natural food was limiting before or after egg laying. However, out data suggest that the former may have been the case. An improved design for food supplementation experiments, which can be used to determine the time of food shortage, is suggested.


The Condor ◽  
2006 ◽  
Vol 108 (4) ◽  
pp. 832-841 ◽  
Author(s):  
Kristine L. Preston ◽  
John T. Rotenberry

Abstract Abstract Timing of breeding activities by birds hasimportant fitness consequences, as deciding when tonest can affect nest success. For three breedingseasons, we provided supplemental food to Wrentits(Chamaeafasciata) inhabitingsemiarid shrublands. We tested the effects of foodsupplementation on timing of initial egg laying,number of nests attempted, timing of fledging, andlength of the breeding season. We also evaluatedwhether Wrentits timed nest initiation to avoidperiods of greatest predation risk. Our study wasconducted during a period of high interannualvariation in precipitation. Supplemental food didnot advance laying date in Wrentits. During adrought, even Wrentits given supplemental fooddelayed nesting, initiated fewer nesting attempts,fledged young earlier, and reduced the length ofthe breeding season. In a year of average rainfall,supplemental food allowed pairs to continuerenesting late into the summer, after repeated nestlosses from predation. Wrentits did not timenesting to avoid periods of greatest predationrisk. In timing initial breeding, Wrentits appearedto be responding to climatic conditions and toindirect cues that predicted environmentalconditions later in the breeding season rather thanto food availability at the time of egg laying.


2019 ◽  
Author(s):  
Mireia Plaza ◽  
Alejandro Cantarero ◽  
Juan Moreno

Female mass in most altricial birds reaches its maximum during breeding at egg-laying, which coincides temporally with the fertile phase when extra-pair paternity (EPP) is determined. Higher mass at laying may have two different effects on EPP intensity. On the one hand, it would lead to increased wing loading (body mass/wing area), which may impair flight efficiency and thereby reduce female’s capacity to resist unwanted extra-pair male approaches (sexual conflict hypothesis). On the other hand, it would enhance female condition, favouring her capacity to evade mate-guarding and to search for extra-pair mates (female choice hypothesis). In both cases, higher female mass at laying may lead to enhanced EPP. To test this prediction, we reduced nest building effort by adding a completely constructed nest in an experimental group of female pied flycatchers (Ficedula hypoleuca). Our treatment caused an increase in mass and thereby wing loading and this was translated into a significantly higher EPP in the manipulated group compared with the control group as expected. There was also a significant negative relationship between EPP and laying date and the extent of the white wing patch, an index of female dominance. More body reserves at laying mean not only a higher potential fecundity but a higher level of EPP as well. This interaction had not previously received due attention but should be considered in future studies of avian breeding strategies.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Cynthia Reséndiz-Infante ◽  
Gilles Gauthier

AbstractMany avian migrants have not adjusted breeding phenology to climate warming resulting in negative consequences for their offspring. We studied seasonal changes in reproductive success of the greater snow goose (Anser caerulescens atlantica), a long-distance migrant. As the climate warms and plant phenology advances, the mismatch between the timing of gosling hatch and peak nutritive quality of plants will increase. We predicted that optimal laying date yielding highest reproductive success occurred earlier over time and that the seasonal decline in reproductive success increased. Over 25 years, reproductive success of early breeders increased by 42%, producing a steeper seasonal decline in reproductive success. The difference between the laying date producing highest reproductive success and the median laying date of the population increased, which suggests an increase in the selection pressure for that trait. Observed clutch size was lower than clutch size yielding the highest reproductive success for most laying dates. However, at the individual level, clutch size could still be optimal if the additional time required to acquire nutrients to lay extra eggs is compensated by a reduction in reproductive success due to a delayed laying date. Nonetheless, breeding phenology may not respond sufficiently to meet future environmental changes induced by warming temperatures.


Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2233
Author(s):  
Loïc Pougnault ◽  
Hugo Cousillas ◽  
Christine Heyraud ◽  
Ludwig Huber ◽  
Martine Hausberger ◽  
...  

Attention is defined as the ability to process selectively one aspect of the environment over others and is at the core of all cognitive processes such as learning, memorization, and categorization. Thus, evaluating and comparing attentional characteristics between individuals and according to situations is an important aspect of cognitive studies. Recent studies showed the interest of analyzing spontaneous attention in standardized situations, but data are still scarce, especially for songbirds. The present study adapted three tests of attention (towards visual non-social, visual social, and auditory stimuli) as tools for future comparative research in the European starling (Sturnus vulgaris), a species that is well known to present individual variations in social learning or engagement. Our results reveal that attentional characteristics (glances versus gazes) vary according to the stimulus broadcasted: more gazes towards unusual visual stimuli and species-specific auditory stimuli and more glances towards species-specific visual stimuli and hetero-specific auditory stimuli. This study revealing individual variations shows that these tests constitute a very useful and easy-to-use tool for evaluating spontaneous individual attentional characteristics and their modulation by a variety of factors. Our results also indicate that attentional skills are not a uniform concept and depend upon the modality and the stimulus type.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1379-1379
Author(s):  
Nicholas Bishop ◽  
Sarah Ullevig ◽  
Krystle Zuniga ◽  
Kaipeng Wang

Abstract Objectives The emergence of food insecurity as a primary nutrition-related health issue among older adults suggests a need to examine how nutritional assistance programs are related to food insecurity and dietary quality in aging populations. This project examines food insecurity and dietary quality in US adults age 65 and older and the impact of nutrition assistance programs. Methods The sample was drawn from the 2012 Health and Retirement Study and 2013 Health Care and Nutrition Study and included 3779 respondents representing a population of 37,217,566 adults aged 65 and older. Food insecurity was a binary measure based on the USDA six-item US Adult Food Security Survey Module. Two forms of nutritional assistance included receipt of supplemental food from sources such as food banks and Meals-on-Wheels (1 = yes, 0 = no) and reported receipt of SNAP benefits (1 = yes, 0 = no). Dietary quality was measured using the Alternative Healthy Eating Index-2010 based on a food frequency questionnaire. General linear modeling adjusting for covariates and complex sampling design was used to test if nutritional assistance moderated the association between food insecurity and AHEI-2010. Results Around 10% of the sample was food insecure, 14% reported receipt of supplemental food, and 6.4% were SNAP benefit recipients. In covariate-adjusted models, food insecurity and receipt of SNAP benefits were not associated with AHEI-2010, but receipt of supplemental food was (b = −1.39, SE = 0.67, P = 0.038). Receipt of supplemental food moderated the association between AHEI-2010 and food insecurity (P = 0.001). Simple effect estimates suggested that among those not receiving supplemental food, the food insecure had lower AHEI-2010 scores than the food secure (b = −2.15, SE = 0.88, P = 0.014). Among those receiving supplemental food, the food insecure had greater AHEI-2010 scores than the food secure (b = 2.62, SE = 1.25, P = 0.035) and similar AHEI-2010 scores as the food secure not receiving supplemental food. Conclusions Preliminary analysis suggests that receipt of supplemental food appears to be associated with better dietary quality among food-insecure older adults and confirms the importance of food assistance programs in combating the negative effect of food insecurity on dietary quality. Funding Sources This work is supported by the Texas State University Research Enhancement Program.


2010 ◽  
Vol 213 (7) ◽  
pp. 1069-1078 ◽  
Author(s):  
A. M. Uchida ◽  
R. A. Meyers ◽  
B. G. Cooper ◽  
F. Goller

2011 ◽  
Vol 43 (5) ◽  
pp. 513-533 ◽  
Author(s):  
SUNITA BOSE

SummaryThis study uses the third National Family Health Survey (2005–06) in India to investigate whether differences in women's status, both at the individual and community levels, can explain the persistent gender differential in nutritional allocation among children. The results show that girls are less likely than boys to receive supplemental food and more likely to be malnourished. In general it appears that higher women's status within a community, as well as higher maternal status, have beneficial effects on a daughter's nutritional status. Further, the moderating effects of community appear to be more consistent and stronger than the individual-level characteristics. A positive relationship between the percentage of literate women in a community and the gender differential in malnutrition appears to be an exception to the general findings regarding the beneficial nature of women's status on a daughter's well-being, showing the need for more than just basic adult literacy drives in communities to overcome the problem of daughter neglect.


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