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The effect of a predator occurrence on vigilance of tits visiting the winter feeder
Tichá, Irena ; Fuchs, Roman (advisor) ; Sedláček, Ondřej (referee)
This thesis evaluates the vigilance parameters of two species of tits affected by the presence of a predator in wintertime. During preferential experiments, tits have had a choice of two feeders in the vicinity of the installed dummy predator. For that purpose was used a dummy sparrowhawk, incomplete or occluded sparrowhawk torsos, and harmless pigeon. It is known that the tits are able to recognize dangerousness presented by the dummy, and according to expected risk dare to visit one of the feeders. It leads to a question whether the tits are somehow influenced by the presence of the dummies, and if so, how specifically are they influenced. It turned out, that the tits in presence of a dangerous dummy significantly increased their vigilance. Both observed species at the feeders behave oppositely. Behaviour of all the birds at the feeder is also affected by their total count at the precise moment and by the presence of a dummy at the other feeder.
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Variabilityin egg shell pigmentation of great tit clutches
Kratochvílová, Anna ; Svobodová, Jana (advisor) ; Veronika, Veronika (referee)
Eggshell coloration in bird clutches shows a striking variability within species which has not yet been fully explained. Its character is determined by the deposition of two main pigments: blue-green biliverdin is responsible for the background colour while brown-red protoporphyrin is associated with the dark spot pattern. Considering the role and matabolism of these two pigments in the avian organism it was suggested that they might have an important impact on the oxidative stress levels and their deposition into the eggshell is therefore suggested to possibly reflect the body condition of laying females during the laying periods. This is also the basic assumption for the signalling hypothesis of eggshell coloration which predicts the eggshell appearance to reflect the female body condition and individual health status or directly indicate aenemia in birds (aenemic hypothesis). Here it was tested whether there is a relationship between parameters representing the body condition of female great tits (Parus major) and the characteristics of protoporphyrin maculation of their eggs. Female body condition was expressed by standardized body weight and the selected haematological parameters (heterophil to lymphocyte ratio and relative immature erythrocyte counts). Eggshell coloration was characterized by spot colour (hue, saturation and brightness), spot counts and the reflectance of the background colour. It was found that females with higher heterophil to lymphocyte ratio laid eggs with more spots and higher reflectance of the background colour in some nesting seasons. Eggs with more spots on its surface were also laid by females with higher immature erythrocyte counts. These results suggest that more intensive deposition of protoporfyring into the eggsell can indicate worse body condition of the laying females. On the other hand, it was also found that heavier females laid eggs with lower reflectance of the background colour. Despite this discrepancy, these results are not inconsistent with the pressumptions of the signalling hypothesis and they partially support the aenemia hypothesis. However, the above mentioned dependencies were inconsistent among the nesting seasons, indicating that further important determinants must be considered in the avian eggshell coloration.
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Sperm phenotype and it's relationship to individual condition
Köstelová, Linda ; Svobodová, Jana (advisor) ; Pavlína, Pavlína (referee)
Animals are known to have evolved many different characters in order to improve their chances during the sexual selection. These secondary sexual characters should correlate with given male´s quality of ejaculate, according to previous research. The literal part of this paper shows us, that the longer the sperm was, the faster, more viable and agile it was. There was a connection between the viability and the length of the middle part of the sperm, that holds the mitochondria. At the same time, sperms with longer tails were faster, as oppose to those with bigger heads, that were slower. This paper was meant to clarify the influence the sperm phenotype on male's ejaculate. For this paper, which focuses on Great tit, the sperm length was chosen as the character of quality. Not only the length of the whole sperm, but also the length of all of its parts were measured. Every one of these parts is associated with the movement and the viability of the sperm in its own way. We tested whether the length of the sperm correlates with characters of the condition or not. The characters we had chosen for this were the length of melanine ornament, the weight of the male, the length of tars and number of leukocytes in blood. The results show that the length of the sperm head correlates with the length of melanine ornament of Great tit. We did not find any other connection among the other secondary sexual characters we had chosen.
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Variability of eggshell colouration
Bubeníčková, Kateřina ; Svobodová, Jana (advisor) ; Sládeček, Martin (referee)
Bird´s Eggs Are Specific for Big Variability in Eggshell Coloration. This Eggshell Eoloration Is Caused by Two Pigments; Biliverdin and Protoporphyrin. Biliverdin Causes Bluegreen Color of the Egg and Protoporphyrin Causes RedBrown and Black Maculas on the Surface of the Eggshell. Many Hypotheses Try to Clarify the Reason of Resultant Variability in the Eggshell Coloration. The Final Reason of the Variability in the Eggshell Coloration Has Not Been yet Explained and this Is the Reason, Why this Topic Is Subject of Scientifical Researches. In the Theoretical Part of this Thesis Are Described Individual Hypotheses, Which Describe Variability in the Eggshell Coloration. These Theses Were Focused on Structural and Signal Function of Pigment and the Anemic Hypothesis; these are Explained in Detail in the thesis, because they are the subjects of this thesis´s Research. Signal Hypothesis Works with Theory, That Egg´s Pigmentation Informs the Partner about Female´s Condition Quality. Results of Recent Published Studies, Which Are Focused on Signal Function, Say, That 60% of Results Support the Theory, That Egg Maculation Relates to Female´s Body Condition. 80% of Studies about Signal Function Made There Researches on Passerines. This Is the Main Reason, Why Signal Function of Pigment Cannot Be Applied Generaly on All Bird Species, because the Signal function Was Not Properaly or None Tested on Other Species Than Passerines (Out of Few Exceptions). Anemic Hypothesis Might Explain the Variability in the Eggshell Coloration with Theory, Protoporphyrin, Which Is Derived in Higher Concetration from Blood Due the Anaemia Causes Higher Maculation on the Surface of Eggshell. Purpose of Practical Part of this Thesis Was Finding Out, Whether Female´s Condition Quality Depends on the Character of Color Maculation in Great tit (Parus major). Futhermore if There Exist Correlation between Ratio (of Immature Red Blood Cells and Total Sum of Red Blood Cells) and Eggshell Coloration. Results of the Study Show, that the Eggshell Coloration May Depend on female´s Conditon. Specifically, Red-Brown Macules with Lower Level of Intensity and Saturation Pronounce Larger Area of Melanin Based Ventral Stripe. In Conclusion, this Thesis Supports Signal Function Thesis of Protoporhyrin and Leads to the Fact, that Final Eggshell Coloration Has an Impact on the Female´s Body Condition. Results of this Thesis Does Not Prove any Relationship Between Ratio (of Immature Red Blood Cells and Total Sum of Red Blood Cells) and Eggshell Coloration. It Leads to the Fact, that there Is No Possible Support for Correlation between Anaemia and Variability in Eggshell Coloration in our Population of Great tit.
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Melanin-based ornaments of birds and their relationship to individual condition
Straka, Antonín ; Svobodová, Jana (advisor) ; Karlíková, Zuzana (referee)
This thesis summarizes findings from literature about the melanin pigment and its properties, melanogenesis, factors affecting the synthesis and tissue deposition of melanin, methods for analysis of ornamental traits of birds, and the relationship of melanin-based ornaments and individual condition. Current studies show that the expression of melanin plumage can be condition-dependent; size or chroma of ornaments frequently signals individual condition. The relationship between condition indicators and the melanin pigment is found more often in achromatic species than in species with melanin- and carotenoid-based plumage. There's a lack of research dealing with pheomelanin ornaments.
Statistical analysis of data obtained from adult male great tits (Parus major) captured during the nesting seasons 2014 and 2015 on sites Čimický háj and Ďáblický háj in Prague was carried out to test the relationship between the size of the melanin-based breast stripe and standardized weight, absolute leukocyte count and tarsus length. Results didn't confirm a link between the area of the breast ornament and analyzed indicators of condition. Future research will take into account other condition parameters which could contribute to explain the role of the breast stripe in sexual selection in the great tit.
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The dynamics of temperature in birdboxes
Slavíková, Z. ; Žalud, Z. ; Bartošová, Lenka ; Fischer, Milan ; Trnka, Miroslav
The aim of the study was to detect the changing temperature in bird boxes of two bird species-collared flycatcher (Ficedula albicollis, T.) and great tit (Parus major, L.). The work is the result of the monitoring of nesting bird species for two years (2009 and 2010) by temperature sensors. Data was continuously recorded for several different breeding pairs with the micro-datalogers MINIKIN. Temperature sensors were fixed directly into the nest with eggs and also in the upper part of bird boxes or outside the boxes. Temperature data was then processed and analyzed. Experimental work was carried out in a floodplain forest in nature reserve Plačkův les a říčka Šatava near Vranovice, altitude: 170; latitude: 48°56´54´´; longitude: 16°35´50´´. The forest is dominated by full-grown, multi-aged canopy with no forestry management. Experimental site belongs to the same natural biogeocenoses group (i.e. Ulmi-fraxineta carpini) and to the same geobotanical group (i.e. suballiance Ulmenion of the Alnion incanae alliance). Our initial hypothesis assumed that the temperature of eggs in the nest and also the time spent in the bird boxes by both bird species (collared flycatcher and great tit) do not differ significantly. The results showed that during the period when the eggs were layed (by both bird species) the temperature were significantly however the temperature of eggs of collared flycatcher and great tit during the period of incubation were very.
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