scholarly journals Relationship of Nutritional Condition of Permanent-Resident Woodland Birds With Woodlot Area, Supplemental Food, and Snow Cover

The Auk ◽  
2003 ◽  
Vol 120 (2) ◽  
pp. 331-336 ◽  
Author(s):  
Paul F. Doherty ◽  
Thomas C. Grubb
Keyword(s):  
Snow Cover ◽  
Fragment Size ◽  
Nutritional Condition ◽  
Forest Fragment ◽  
Woodland Birds ◽  
Supplemental Food ◽  
Poecile Carolinensis ◽  
Permanent Resident ◽  
Tufted Titmouse ◽  
Relationship Of

Abstract In a previous study we found that survivorship of several species of permanent-resident, temperate-zone birds was positively related to forest fragment size and presence of supplemental food, and negatively related to extent of snow cover (Doherty and Grubb 2002). Here, we test the hypothesis that such trends are related to differential nutritional condition during winter. Employing rate of growth of induced feathers, we found that woodlot size and presence of supplemental food interacted to increase the nutritional condition of Carolina Chickadees (Poecile carolinensis) and that Tufted Titmouse (Baeolophus bicolor) nutritional condition was reduced in years with high snow cover. Assuming that nutritional condition is positively related to survivorship, these results have possible implications for the viability of permanent-resident birds in small woodlots, with the effects on subordinate species in foraging flocks in very small woodlots possibly being the most severe.

scholarly journals The Influence of Kinship on Nutritional Condition and Aggression Levels in Winter Social Groups of Tufted Titmice

The Condor ◽  
2001 ◽  
Vol 103 (4) ◽  
pp. 821-828 ◽  
Author(s):  
Elena V. Pravosudova ◽  
Thomas C. Grubb ◽  
Patricia G. Parker
Keyword(s):  
Dna Fingerprinting ◽  
Social Groups ◽  
Nutritional Condition ◽  
Limited Resources ◽  
Brood Care ◽  
Permanent Resident ◽  
Tufted Titmouse ◽  
Los Grupos

Abstract During winter, adult Tufted Titmice (Baeolophus bicolor) share their territories with both offspring and immigrant young. For such situations in social permanent-resident birds, the prolonged brood care hypothesis (Ekman and Rosander 1992) states that adults should be more tolerant of their own young than of unrelated immature birds, allowing their offspring better access to limited resources. We tested two predictions from this hypothesis using the Tufted Titmouse: (1) offspring should be in better nutritional condition than immigrants; (2) territorial adults should be more aggressive toward immigrant immature birds than toward their own offspring. We estimated relatedness using DNA fingerprinting. To assess nutritional condition, we used a fatness index and ptilochronology. We found no difference between the condition of retained and immigrant young. We tested the second prediction by recording aggressiveness among the individually marked members of social groups. Supporting the second prediction, territorial adults were significantly more aggressive toward unrelated than related immature birds. Influencia del Parentezco en la Condición Nutricional y Niveles de Agresividad en Grupos Sociales de Invernada de Baeolophus bicolor Resumen. Durante el invierno, los individuos adultos de Baeolophus bicolor comparten sus territorios con su descendencia y con jóvenes inmigrantes. Dada esta situación en aves sociales que son residentes permanentes, la hipótesis de cuidado prolongado de la nidada (Ekman y Rosander 1992) establece que los adultos deberían ser más tolerantes con sus propios hijos que con aves inmaduras no relacionadas, permitiéndole a su descendencia mejor acceso a recursos limitados. Evaluamos dos predicciones de esta hipótesis usando a B. bicolor: (1) los hijos deberían presentar una mejor condición nutricional que los inmigrantes; (2) los adultos territoriales deberían ser más agresivos con las aves inmaduras inmigrantes que con su propia descendencia. Estimamos el grado de parentezco utilizando huellas dactilares genéticas. Empleamos un índice de grasitud y ptilocronología para establecer la condición nutricional. No encontramos diferencias entre las condiciones de los jóvenes retenidos e inmigrantes. Evaluamos la segunda predicción registrando la agresividad entre miembros individualmente marcados de los grupos sociales. Los adultos territoriales fueron significativamente más agresivos con aves no relacionadas que con inmaduros relacionados, apoyando la segunda predicción.

scholarly journals Small mammal glucocorticoid concentrations vary with forest fragment size, trap type, and mammal taxa in the Interior Atlantic Forest

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah A. Boyle ◽  
Noé U. de la Sancha ◽  
Pastor Pérez ◽  
David Kabelik
Keyword(s):  
Atlantic Forest ◽  
Small Mammals ◽  
Acute Stress ◽  
Physiological Stress ◽  
Fragment Size ◽  
Hair Shaft ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Trapping Methods ◽  
Free Ranging

AbstractSpecies that live in degraded habitats often show signs of physiological stress. Glucocorticoid hormones (e.g., corticosterone and cortisol) are often assessed as a proxy of the extent of physiological stress an animal has experienced. Our goal was to quantify glucocorticoids in free-ranging small mammals in fragments of Interior Atlantic Forest. We extracted glucocorticoids from fur samples of 106 small mammals (rodent genera Akodon and Oligoryzomys, and marsupial genera Gracilinanus and Marmosa) from six forest fragments (2–1200 ha) in the Reserva Natural Tapytá, Caazapá Department, Paraguay. To our knowledge, this is the first publication of corticosterone and cortisol levels for three of the four sampled genera (Akodon, Oligoryzomys, and Marmosa) in this forest system. We discovered three notable results. First, as predicted, glucocorticoid levels were higher in individuals living withing small forest fragments. Second, animals captured live using restraint trapping methods (Sherman traps) had higher glucocorticoid levels than those animals captured using kill traps (Victor traps), suggesting that hair glucocorticoid measures can reflect acute stress levels in addition to long-term glucocorticoid incorporation. These acute levels are likely due to urinary steroids diffusing into the hair shaft. This finding raises a concern about the use of certain trapping techniques in association with fur hormone analysis. Finally, as expected, we also detected genus-specific differences in glucocorticoid levels, as well as cortisol/corticosterone ratios.

scholarly journals ЦАХИЛДАГНЫ ТӨРЛИЙН УРГАМЛЫН ФИЛОГЕНЕТИК ХОЛБОО

2016 ◽  
pp. 25-31
Author(s):  
Х Алтанзул ◽  
Ю Оюунбилэг
Keyword(s):  
Phylogenetic Tree ◽  
Phylogenetic Relationship ◽  
Dna Sequences ◽  
Fragment Size ◽  
Dna Fragment ◽  
Relationship Of

The phylogenetic relationship of eight Iris species (I.flavisimma, I.ventricosa, I.bungei,I.kaempferi, I.tenuifolia, I.lactea, I.tigrida, I.dichotoma) were studied by PCR using six specificprimers (S-523, Z1204R, trnL, trnF and ITS1, ITS4). All species except I.ventricosa wereidentified when using S-523, Z1204R and trnL, trnF primers and the DNA fragment size rangedbetween 500 to 600 bp and 800 bp, respectively. Primers ITS1 and ITS4 produced double bandsin about 500 and 1500 bp to I.bungei, I.kaempferi, and I.lactea species. On the phylogenetic tree, some iris species have close relations based on chloroplastic DNA sequences. The closest relationships showed between I.sanguinea and I.sibirica, I.rutenica and I.uniflora. Also I.tenuifolia, I.ventricosa and I.halophila located on one branch of phylogenetic tree.

scholarly journals The Development of Snow and Glacier Research in Switzerland

1948 ◽  
Vol 1 (04) ◽  
pp. 192-201 ◽  
Author(s):  
R. Haefeli
Keyword(s):  
Mechanical Properties ◽  
Snow Cover ◽  
Laboratory Experiments ◽  
Relationship Of ◽  
The Relationship ◽  
Research Institute

The evolution of snow and glacier research in Switzerland is outlined. The settling, creep, viscosity and slipping of the snow cover are discussed in detail and the relationship of these comparatively simple processes to the more complex movements in a glacier are described. The importance of further research in glacier physics in connection with the crystallographic and mechanical properties of ice is stressed; certain preliminary laboratory experiments and some subjects for further research in the field are suggested. The Great Aletsch Glacier is recommended for this owing to the proximity of the Jungfraujoch Research Institute and facilities for transport by the Jungfraujoch Railway.

Forest fragment size and microhabitat effects on palm seed predation

2006 ◽  
Vol 131 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Marina Fleury ◽  
Mauro Galetti
Keyword(s):  
Seed Predation ◽  
Fragment Size ◽  
Forest Fragment

Relationship of White Spruce to Lenses of Perennially Frozen Ground, Mount McKinley National Park, Alaska

ARCTIC ◽  
1965 ◽  
Vol 18 (4) ◽  
pp. 262 ◽  
Author(s):  
Leslie A. Viereck
Keyword(s):  
Snow Cover ◽  
National Park ◽  
White Spruce ◽  
Parent Material ◽  
Silty Clay ◽  
Frozen Ground ◽  
Moss Layer ◽  
Individual Trees ◽  
Relationship Of

Reports investigations of perennially frozen mounds beneath individual trees growing in silty clay on a terrace of the McKinley River. Climate, vegetation and parent material of the spruce stand are described. The mounds, 2-4 m in diam, contain a frozen lens-shaped core. The permafrost results from lower temperatures under the trees due to less snow cover and a thicker moss layer. A proposed cycle of development and collapse of the tree mounds is outlined.

scholarly journals Effects of Forest Fragment Size and Successional Stage on Mixed-Species Bird Flocks in Southeastern Brazil

The Condor ◽  
2000 ◽  
Vol 102 (3) ◽  
pp. 585-594 ◽  
Author(s):  
Marcos Maldonado-Coelho ◽  
Miguel  Marini
Keyword(s):  
Species Richness ◽  
Size Structure ◽  
Fragment Size ◽  
Southeastern Brazil ◽  
Size Analysis ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Mixed Species ◽  
Successional Stage ◽  
Mixed Species Flocks

Abstract We analyzed patterns of species richness, size, structure, and composition of mixed-species flocks in relation to forest fragment size and forest successional stage during dry and rainy seasons, at the state of Minas Gerais, southeastern Brazil. Three forest fragments (1.7, 50, and 200 ha) were used for fragment size analysis, and two fragments (200 and 300 ha) were used for successional stage analysis. Fragment size and season affected flock richness, size, stability, and composition. In the 1.7-ha fragment, flock species richness, size, and stability were significantly different only during the rainy season. Fragment successional stage also influenced flock richness and size, although season did not. Flock composition also had changes related to fragment successional stage. Fragment geometry seems to be an important factor influencing flock structure and composition.

Sign in / Sign up

Export Citation Format

Share Document