scholarly journals Predictability of food supply modulates nocturnal hypothermia in a small passerine

2020 ◽  
Vol 16 (6) ◽  
pp. 20200133 ◽  
Author(s):  
Johan F. Nilsson ◽  
Jan-Åke Nilsson ◽  
Juli Broggi ◽  
Hannah Watson
Keyword(s):  
Food Availability ◽  
Food Supply ◽  
Food Source ◽  
Parus Major ◽  
Cold Winter ◽  
Free Living ◽  
Supplementary Food ◽  
Treatment Groups ◽  
Sufficient Energy ◽  
Short Days

The combination of short days and long cold winter nights, in temperate regions, presents a major challenge for small diurnal birds. Small birds regularly employ heterothermy and enter rest-phase hypothermia during winter nights to conserve energy. However, we know little about how environmental conditions, such as food availability, shape these strategies. We experimentally manipulated food availability in winter to free-living great tits Parus major . A ‘predictable' and constant food supply was provided to birds in one area of a forest, while birds in another area did not have access to a reliable supplementary food source. We found that predictability of food affected the extent of nocturnal hypothermia, but the response differed between the sexes. Whereas male nocturnal body temperature was similar regardless of food availability, females exposed to a naturally ‘unpredictable' food supply entered deeper hypothermia at night, compared with females that had access to predictable food and compared with males in both treatment groups. We suggest that this response is likely a consequence of dominance, and subdominant females subject to unpredictable food resources cannot maintain sufficient energy intake, resulting in a higher demand for energy conservation at night.

scholarly journals Personality predicts spatial responses to food manipulations in free-ranging great tits ( Parus major )

2009 ◽  
Vol 6 (2) ◽  
pp. 187-190 ◽  
Author(s):  
Thijs van Overveld ◽  
Erik Matthysen
Keyword(s):  
Natural Environment ◽  
Food Supply ◽  
Abrupt Change ◽  
Parus Major ◽  
Free Living ◽  
Personality Differences ◽  
Spatial Response ◽  
Spatio Temporal ◽  
Induced Changes ◽  
Free Ranging

Personality differences measured under standardized lab-conditions are assumed to reflect differences in the way individuals cope with spatio-temporal changes in their natural environment, but few studies have examined how these are expressed in the field. We tested whether exploratory behaviour in a novel environment predicts how free-living individual great tits ( Parus major ) react to a change in food supply. We temporarily removed food at feeding stations during two summers and recorded the behavioural response of juvenile birds to these food manipulations using radio-tracking. When challenged by an abrupt change in food supply, fast-exploring individuals more rapidly switched to different foraging areas at longer distances from the feeder. This study is the first to show that personality traits predict the spatial response to experimentally induced changes in their natural environment.

scholarly journals Feasibility of planctomycetes as a nutritional or supplementary food source forDaphniaspp

2016 ◽  
Vol 52 ◽  
pp. 317-325 ◽  
Author(s):  
S. C. Antunes ◽  
R. A. Almeida ◽  
T. Carvalho ◽  
O. M. Lage
Keyword(s):  
Food Source ◽  
Supplementary Food

scholarly journals Food availability limits avian reproduction in the city: An experimental study on great tits Parus major

2020 ◽  
Vol 89 (7) ◽  
pp. 1570-1580 ◽  
Author(s):  
Gábor Seress ◽  
Krisztina Sándor ◽  
Karl L. Evans ◽  
András Liker
Keyword(s):  
Experimental Study ◽  
Food Availability ◽  
Parus Major ◽  
Avian Reproduction ◽  
The City

scholarly journals Basal blood glucose concentration in free-living striped mice is influenced by food availability, ambient temperature and social tactic

2015 ◽  
Vol 11 (5) ◽  
pp. 20150208 ◽  
Author(s):  
Carsten Schradin ◽  
Neville Pillay ◽  
Anna Kondratyeva ◽  
Chi-Hang Yuen ◽  
Ivana Schoepf ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Ambient Temperature ◽  
Food Availability ◽  
Glucose Concentration ◽  
Extended Family ◽  
Blood Glucose Concentration ◽  
Energy Regulation ◽  
Free Living ◽  
Blood Samples ◽  
Rhabdomys Pumilio

Vertebrates obtain most of their energy through food, which they store mainly as body fat or glycogen, with glucose being the main energy source circulating in the blood. Basal blood glucose concentration (bBGC) is expected to remain in a narrow homeostatic range. We studied the extent to which bBGC in free-living African striped mice ( Rhabdomys pumilio ) is influenced by ecological factors with a bearing on energy regulation, i.e. food availability, abiotic environmental variation and social tactic. Striped mice typically form extended family groups that huddle together at night, reducing energetic costs of thermoregulation, but solitary individuals also occur in the population. We analysed 2827 blood samples from 1008 individuals of seven different social categories that experienced considerable variation in food supply and abiotic condition. Blood samples were taken from mice in the morning after the overnight fast and before foraging. bBGC increased significantly with food plant abundance and decreased significantly with minimum daily ambient temperature. Solitary striped mice had significantly higher bBGC than group-living striped mice. Our results suggest that adaptive responses of bBGC occur and we found large natural variation, indicating that bBGC spans a far greater homeostatic range than previously thought.

The importance of exogenous contamination on heavy metal levels in bird feathers. A field experiment with free-living great tits, Parus major

2004 ◽  
Vol 6 (4) ◽  
pp. 356 ◽  
Author(s):  
Jaspers Veerle ◽  
Dauwe Tom ◽  
Pinxten Rianne ◽  
Bervoets Lieven ◽  
Blust Ronny ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Field Experiment ◽  
Parus Major ◽  
Free Living ◽  
Metal Levels

scholarly journals Drd4 gene polymorphisms are associated with personality variation in a passerine bird

2007 ◽  
Vol 274 (1619) ◽  
pp. 1685-1691 ◽  
Author(s):  
Andrew E Fidler ◽  
Kees van Oers ◽  
Piet J Drent ◽  
Sylvia Kuhn ◽  
Jakob C Mueller ◽  
...  
Keyword(s):  
Transcription Initiation ◽  
Gene Polymorphisms ◽  
Parus Major ◽  
Passerine Bird ◽  
Initiation Site ◽  
Novelty Seeking ◽  
Coding Region ◽  
Free Living ◽  
Single Nucleotide ◽  
Genetic Epistasis

Polymorphisms in several neurotransmitter-associated genes have been associated with variation in human personality traits. Among the more promising of such associations is that between the human dopamine receptor D4 gene ( Drd4 ) variants and novelty-seeking behaviour. However, genetic epistasis, genotype–environment interactions and confounding environmental factors all act to obscure genotype–personality relationships. Such problems can be addressed by measuring personality under standardized conditions and by selection experiments, with both approaches only feasible with non-human animals. Looking for similar Drd4 genotype–personality associations in a free-living bird, the great tit ( Parus major ), we detected 73 polymorphisms (66 SNPs, 7 indels) in the P. major Drd4 orthologue. Two of the P. major Drd4 gene polymorphisms were investigated for evidence of association with novelty-seeking behaviour: a coding region synonymous single nucleotide polymorphism (SNP830) and a 15 bp indel (ID15) located 5′ to the putative transcription initiation site. Frequencies of the three Drd4 SNP830 genotypes, but not the ID15 genotypes, differed significantly between two P. major lines selected over four generations for divergent levels of ‘early exploratory behaviour’ (EEB). Strong corroborating evidence for the significance of this finding comes from the analysis of free-living, unselected birds where we found a significant association between SNP830 genotypes and differing mean EEB levels. These findings suggest that an association between Drd4 gene polymorphisms and animal personality variation predates the divergence of the avian and mammalian lineages. Furthermore, this work heralds the possibility of following microevolutionary changes in frequencies of behaviourally relevant Drd4 polymorphisms within populations where natural selection acts differentially on different personality types.

scholarly journals Stressful colours: corticosterone concentrations in a free-living songbird vary with the spectral composition of experimental illumination

2015 ◽  
Vol 11 (8) ◽  
pp. 20150517 ◽  
Author(s):  
Jenny Q. Ouyang ◽  
Maaike de Jong ◽  
Michaela Hau ◽  
Marcel E. Visser ◽  
Roy H. A. van Grunsven ◽  
...  
Keyword(s):  
Large Scale ◽  
Red Light ◽  
Spectral Composition ◽  
Parus Major ◽  
Light Spectrum ◽  
Night Time ◽  
Free Living ◽  
Treatment Type ◽  
Artificial Illumination ◽  
Living Organisms

Organisms have evolved under natural daily light/dark cycles for millions of years. These cycles have been disturbed as night-time darkness is increasingly replaced by artificial illumination. Investigating the physiological consequences of free-living organisms in artificially lit environments is crucial to determine whether nocturnal lighting disrupts circadian rhythms, changes behaviour, reduces fitness and ultimately affects population numbers. We make use of a unique, large-scale network of replicated field sites which were experimentally illuminated at night using lampposts emanating either red, green, white or no light to test effect on stress hormone concentrations (corticosterone) in a songbird, the great tit ( Parus major ). Adults nesting in white-light transects had higher corticosterone concentrations than in the other treatments. We also found a significant interaction between distance to the closest lamppost and treatment type: individuals in red light had higher corticosterone levels when they nested closer to the lamppost than individuals nesting farther away, a decline not observed in the green or dark treatment. Individuals with high corticosterone levels had fewer fledglings, irrespective of treatment. These results show that artificial light can induce changes in individual hormonal phenotype. As these effects vary considerably with light spectrum, it opens the possibility to mitigate these effects by selecting street lighting of specific spectra.

Differences in growth rate, body condition, habitat use and food availability between island and mainland lizard populations ofAnolis nebulosusin Jalisco, Mexico

2014 ◽  
Vol 30 (5) ◽  
pp. 493-501 ◽  
Author(s):  
Héctor Hugo Siliceo-Cantero ◽  
Andrés García
Keyword(s):  
Growth Rate ◽  
Habitat Use ◽  
Food Availability ◽  
Body Condition ◽  
Food Supply ◽  
Geographic Isolation ◽  
Seasonal Fluctuations ◽  
Continental Population ◽  
Two Populations

Abstract:Lizards of the genusAnolishave been widely studied, however, little is known about the effects of environmental seasonality, food availability and geographic isolation on body condition, growth rate and habitat use of lizards. The existence of an insular and a continental population ofAnolis nebulosus(clouded anole), separated by only 0.47 km, represents an ideal opportunity to address this topic. We compared seasonal fluctuations in food availability (arthropod density) for anoles, as well as body condition, growth rate and habitat use in the two populations. Food availability throughout the year was sampled every 2 mo by trapping arthropods at each site. Lizards were also monitored and measured every 2 mo by surveying three quadrats in each site over 2 y giving a total of 30 visits for each quadrat. Results suggested that composition and density of food supply was similar for the two populations. Nevertheless, food supply responded to seasonality of rainfall, with an increase of 1.5 times during the rainy season. Despite similarity in food availability, insular anoles had body condition that was 5–10 times better, with growth rate twice as fast, and used similar perches. The role of predation, and inter- and intraspecific competition are discussed as possible drivers.

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