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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Inkiluose perinčių žvirblinių paukščių veisimosi dėsningumai ir galima klimato kaitos įtaka / Regularities of nest box breeding passerine birds and possible impact of climate change

Šimkevičius, Kastytis 14 January 2009 (has links)
Magistro darbe tiriama miško aplinkos sąlygų ir klimato kaitos įtaka inkiluose perintiems žvirbliniams paukščiams. Darbo objektas – inkiluose perintys žvirbliniai paukščiai. Darbo tikslas – ištirti žvirblinių paukščių veisimosi dėsningumus Kazlų Rūdos miškų masyve ir įvertinti klimato kaitos poveikį. Darbo metodai – sistemingai iškeltų inkilų stebėjimas, loginė literatūros analizė, statistinė duomenų analizė. Darbo rezultatai. Atlikus tyrimus Kazlų Rūdos mokomosios miškų urėdijos Jūrės girininkijos miškuose, įvertintas miško aplinkos veiksnių ir klimato kaitos poveikis didžiosios zylės Parus major L. ir margasparnės musinukės Ficedula hypoleuca Pall. veisimuisi ir gauti tokie rezultatai: didžiosios zylės pirmojo kiaušinio padėjimo laiką tiesiogiai įtakoja vidutinė paros temperatūra, tačiau reakcija yra uždelsta 4 dienomis; didžiosios zylės antrojoje vadoje arčiau miško aikštės, kirtavietės ar jaunuolyno krašto deda didesnes dėtis; šiltėjančio klimato pasėkoje didžiosios zylės pradeda veistis vidutiniškai 5 dienomis anksčiau lyginant su A. Aleknonio pateiktais duomenimis (1958-1982); dėl ankstesnio didžiųjų zylių veisimosi pirmojoje vadoje, taip pat dėl pailgėjusio periodo su aukštesnėmis temperatūromis antra vada pradedama dėti anksčiau ir būna gausesnė. / This study is analyzing Forest environment conditions and changes in climate influence on breeding passerine birds hatched in nest boxes. The Object – Passerine birds breeding in nest boxes. The aim of this paper is to investigate regularities of breeding passerine birds in Kazlų Rūda forest and to estimate possible impact of climate change. Methods – observation of systematically placed nest boxes, logical literature analysis, statistical analysis of data. Results. Study was carried on Training State Forest Enterprise of Kazlų Rūda, Forestry of Jūrė. Impact of forest environment and changes in climate on breeding of Great Tit (Parus major) and Pied Fly Catcher (Ficedula hypoleuca) were estimated. Following results were found: time of first laying egg is directly influenced by mean temperature of the day, but reaction time is delayed for 4 days; in the second broad that are closer to the forest openings, forest cuttings or brush stage forest edge Great Tits are laying more eggs; thought the warming of the climate Great Tits starts to breed 5 days earlier comparing to data by A. Aleknonis (1958-1982); regarding earlier breeding of Great Tits in first broad, either prolonged period with higher temperatures second broad is relatively larger and initiated to lay earlier.
142

WASP AND BIRD NESTING INTERACTIONS WITH SPECIAL REFERENCE TO POLISTES DOMINULA

Earley, Christopher Gene 15 August 2013 (has links)
Polistes dominula and P. fuscatus often nest in bird nest boxes. Potential competition between wasps and birds was studied by removing wasp nests from some boxes. No difference in nesting success of breeding birds was found between boxes with wasp nests and those in which wasp nests were removed. Boxes that never had a wasp nest and boxes from which wasp nests were removed differed greatly in bird occupancy, suggesting that birds detected previous wasp presence. Some bird species gain protection by nesting near wasp nests. Birds may prefer to nest near wasp species that inflict higher sting pain levels. A rank correlation of data from published studies provided no evidence that pain level influences which wasp nests are most attractive to nesting birds. A comprehensive table of bird-wasp nesting associations (listing 121 bird species, 28 wasp species and 4 bee species) is included here.
143

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Unknown Date
No description available.
144

Nest site selection by the American kestrel, Falco sparverius

Spiegel, Stephen. January 1975 (has links)
No description available.
145

Hyperreflexivity of the bounded n-cocycle spaces of Banach algebras

2014 August 1900 (has links)
The concept of hyperreflexivity has previously been defined for subspaces of $B(X,Y)$, where $X$ and $Y$ are Banach spaces. We extend this concept to the subspaces of $B^n(X,Y)$, the space of bounded $n$-linear maps from $X\times\cdots\times X=X^{(n)}$ into $Y$, for any $n\in \mathbb{N}$. If $A$ is a Banach algebra and $X$ a Banach $A$-bimodule, we obtain sufficient conditions under which $\Zc^n(A,X)$, the space of all bounded $n$-cocycles from $A$ into $X$, is hyperreflexive. To do so, we define two notions related to a Banach algebra: The strong property $(\B)$ and bounded local units (b.l.u). We show that there are sufficiently many Banach algebras which have both properties. We will prove that all C$^*$-algebras and group algebras have the strong property $(\B).$ We also prove that finite CSL algebras and finite nest algebras have this property. We further show that for an arbitrary Banach algebra $A$ and each $n\geq 2$, $M_n(A)$ has the strong property $(\B)$ whenever it is equipped with a Banach algebra norm. In particular, this implies that all Banach algebras are embedded into a Banach algebra with the strong property $(\B)$. With regard to bounded local units, we show that all $C^*$-algebras and many group algebras have b.l.u. We investigate the hereditary properties of both notions to construct more example of Banach algebras with these properties. We apply our approach and show that the bounded $n$-cocycle spaces related to Banach algebras with the strong property $(\B)$ and b.l.u. are hyperreflexive provided that the space of the corresponding $n+1$-coboundaries are closed. This includes nuclear C$^*$-algebras, many group algebras, matrix spaces of certain Banach algebras and finite CSL and nest algebras. We finish the thesis with introducing {\it the hyperreflexivity constant}. We make our results more precise with finding an upper bound for the hyperreflexivity constant of the bounded $n$-cocycle spaces.
146

Nest site selection by the red-shouldered hawk (Buteo lineatus) in southwestern Québec

Morris, Michael Murray Joseph. January 1980 (has links)
No description available.
147

Nesting ecology and hatching success of the painted turtle (Chrysemys picta) in southwestern Quebec

Christens, Elaine. January 1985 (has links)
No description available.
148

Behavioural plasticity of life history traits in the New Zealand avifauna

Starling, Amanda January 2006 (has links)
The purpose of this research was to determine how predator control influences nest survival and changes in life history strategies of birds. All studies were conducted at two sites: one site had very little mammal control, while the other site is a 'mainland island' in which all introduced mammals were trapped or poisoned. Nest survival rates of introduced and native species were compared between the two sites by locating and monitoring nests of nine species. I found that mammalian predator control increased nest survival rates of both introduced and native species, but the incrase of nest survival was more pronounced in native species. The influence of predator control on the plasticity of life history strategies in introduced and native New Zealand birds was also examined. Some life history strategies (e.g. time spent incubating, frequency of visits to the nest) changed significantly in the area with predator control, while other life history traits (e.g. clutch size) did not vary between areas. I found that both introduced and native New Zealand birds changed a variety of life history traits and that the changes were likely a plastic response to the recent change in predator numbers. As it has been suggested that birds may become less responsive to mammals when predators are controlled, I tested the response of birds to a model of a feral cat. Birds in the predator control area were significantly less likely to recognise the cat model as a potential threat. This suggests the recognition of predators can be rapidly lost from a population. My research confirms that mammal control can increase nest success of native species, but reductions in predator numbers can also change a variety of life history traits and behaviours. As the removal of mammalian predators also appears to make birds less responsive to potential predators, it is important for continued mammalian control once management has begun. Otherwise, any reintroduction of predatory mammals into controlled sites would likely place such bird populations at greater risk as they would have behaviours suited to an environment with lowered nest predation risk.
149

Cannibalism in laying hens : characteristics of individual hens and effects of perches during rearing /

Yngvesson, Jenny, January 2002 (has links) (PDF)
Diss. (sammanfattning) Skara : Sveriges lantbruksuniv., 2002. / Härtill 4 uppsatser.
150

Comparaison et suivi des communautés d'oiseaux nicheurs dans des pessières noires boréales issues de coupes et de feux /

Imbeau, Louis, January 1996 (has links)
Mémoire (M.Ress.Renouv.)--Université du Québec à Chicoutimi, 1996. / Document électronique également accessible en format PDF. CaQCU

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