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My thesis deals with the study of the population of the Long-eared Owl (Asio otus) on a wintering place in Kladno - Kročehlavy. I mention numbers, arrivals and departures of the Long-eared Owl during the years 2013-2015 and the influence of abiotic factors on these results. I also deal with ringing and recoveries of these owls in the territory of Kladno. I verify the hypothesis of the influence of warm weather, rainfall and snow cover on the representation of small mammals and birds species in the diet of the Long-eared Owl in this thesis. In addition, my thesis is devoted to the analysis of methodology and species identification in food of the Long-eared Owl by skulls and pelvic bones. In my thesis, when determining the type of small mammals I deal with sexing of Common Vole (Microtus arvalis) and Wood Mouse (Apodemus sylvaticus) of the pelvic bones. According to bone fragments of the pelvis dominant representation of male Common Voles and Wood Mouse in a certain period of winter was investigated. On the basis of the obtained results I have compiled charts and tables and I have compared them with previous research from the years 2006 - 2012 in the same study area in Kladno - Kročehlavy. Keywords: Long-eared Owl (Asio otus), diet, weather, Common Vole (Microtus arvalis), Wood Mouse (Apodemus...

I evaluated the use of various wetlands by wintering ducks in the Tulare Lake Basin (TLB), California, during October 1982 - April 1983 and September 1983 - March 1984. Aerial waterfowl counts of the TLB were used to document spacial use patterns by ducks. Ground surveys on evaporation ponds in the Tulare Lake Drainage District (TLDD) were used to evaluate duck use of specific ponds with varying chemical and biological parameters. During mid-winter, up to 300,000 ducks used the TLB. The most abundant species (northern pintail (Anas acuta), northern shoveler (Anas clvoeata), and green-winged teal (Anas crecca)) were found on freshwater habitats. Ruddy ducks (Oxvura jamaicensis) were the only species to extensively use the evaporation ponds. With the exception of ruddy ducks, the evaporation ponds did not appear to be valuable for feeding areas, but provided sanctuary during the hunting season. The use of evaporation ponds by waterfowl may be heavier in years without the extensive floodwater that was present during this study. / Graduation date: 1991

Žiemojantys vandens paukščiai Lietuvos pajūryje 2006, 2007 ir 2008 m. žiemojimo laikotarpiu tirti naudojant standartinę apskaitų nuo kranto metodiką. Gausiausiai stebėtos rūšys buvo: nuodėgulė, ledinė antis, didysis dančiasnapis, ausuotasis kragas, klykuolė, sibirinė gaga. Darbe yra pateikiama 2006, 2007 ir 2008 metų žiemos stebėjimo sezonų duomenų analizė, kurioje yra nagrinėjama vandens paukščių rūšinė sudėtis tiek 2006, 2007 ir 2008 metais atskirai, bei tarp atskirų teritorijų skirtingais metais. Palangos priekrantė 2006, 2007 ir 2008 metų stebėjimo sezonais buvo svarbi didžiųjų dančiasnapių, ausuotųjų kragų, klykuolių, ledinių ančių ir sibirinių gagų susitelkimo vieta. Priekrantė ties Kuršių nerija 2006–2007 metų stebėjimo sezonais buvo svarbi žiemojančioms nuodėgulėms, ledinėms antims ir ausuotiesiems kragams. Taip pat nagrinėjau žiemojančių vandens paukščių pasiskirstymą Lietuvos Baltijos jūros priekrantėje ties Palanga, bei ties Kuršių nerija tais pačiais, bei skirtinagais tyrimų sezonais. Ledinių ančių pagrindinės sankaupos stebėtos ties Giruliais ir mažesnė dalis iki Palangos tilto, nuodėgulių - ties Juodkrante ir Smiltyne. Klykuolių didesnės sankaupos stebėtos tarp Karklės ir Palangos tilto. Ausuotųjų kragų pasiskirstymas priekrantėje sąlyginai tolygus tiek ties Kuršių nerija, tiek ties Palanga. / Wintering wterbirds in Lithuanian costal waters were investigated in 2006–2007–2008 standart land-based surveys were used. Abuot 11900 in 2006, 6600 in 2007 and 4192 in 2008 waterbirds were cuonted. 20 species were recorded wintering in Lithuanian inshore waters of the Baltic sea. Velvet Scoter, Long-tailed Duck, Goosander, Great Crested Grebe, Goldeneye, Steller‘s Eider were the most numeruos species. Analysis of the wintering waterbird species composition in diferent years in the same study site and in different years in the same site in 2006–2007–2008 wintering seasons is presented. The coastal waters off the Palanga were important for wintering Long-tailed Ducks, Goosanders, Great Crested Grebes, Goldeneyes, Steller‘s Eiders in 2006–2007–2008 seasons. The coastal waters off the Curonian Spit were important for wintering Velvet Scoters, Long-tailed Ducks, Great Crested Grebes. Distribution of wintering waterbirds in the Lithuanian inshore waters in 2006–2007–2008 wintering seasons was also analysed. The greatest concentrations of Long-tailed Ducks were observed near the Giruliai and smaller numbers – all the way to Palanga bridge in the north, Velvet Scoters – between Juodkrante and Smiltyne. The greatest concentrations of Goldeneyes were observed between Karkle and the Palanga bridge. Great Crested Grebes were rather evenly distributed along the coastal waters both off the Palanga and the Curonian Spit coasts.

A growing world population drives an ever-increasing need for food and energy. These challenges, along with depletion of water and fossil fuel resources, call for improvements in crop production systems and the cultivars used within them. Perennial cropping systems present an attractive solution to many of these problems. A greater understanding of the genetic control of over-wintering ability within crop species is one way to begin the process of making perennial cropping systems a possibility. In this study an F3:F4 family derived from a cross between Sorghum bicolor (L.) Moench and S. propinquum (Kunth) Hitchc. segregating for rhizome production was phenotyped in both field and greenhouse environments for traits relating to rhizomatousness and over-wintering. Several statistical models were created to correlate rhizome growth and over-wintering. A known rhizome quantitative trait locus (QTL) region was saturated with SSR markers and the QTL interval was reduced from previous estimates of about 16 Mb or 7 cM to 12 Mb or 2 cM, a 25% or 71% reduction in physical or linkage distance respectively. Two previously unidentified QTL regions associated with over-wintering were also identified. Our results also support the hypothesis that rhizome growth is important and possibly necessary for over-wintering in Sorghum.

This study is an examination of the use of coastal estuaries and nearby farmland as habitat by dabbling ducks (mallard and American wigeon) during migrating and wintering periods. Its aim was to identify aspects of British Columbia coastal habitat of importance to dabblers through an analysis of the ducks' movements among habitat types and through a description of where and on what ducks feed. Data were collected in 1979 and 1980 along a 30 km stretch of coastline on southeastern Vancouver Island. Results are presented in 3 parts. Part 1 examines the relative use of farm and coastal habitat through a series of censuses conducted weekly at 8 farm and 8 coastal sites. The strong negative correlation between counts at farm and coastal sites indicates that dabblers treat them as alternative habitats. The numbers of ducks on farms was positively correlated with the area of standing water on the fields. Farm habitat, apparently preferred during warm, wet weather, was not used when fields were dry or frozen. Part 2 is a description of feeding location on fields, at estuaries and at a shallow, nonestuarine bay. It is based on observations at selected sites at high and low tide levels. Each duck in each observation period was classified as to location and activity. Both species fed primarily in shallow water, their feeding location shifting with the tides. Both marsh and marine sections of estuaries were used extensively for feeding. The shallow bay was used especially by American wigeon at low tide in fall and early winter. The high marsh areas at estuaries were particularly attractive to mallards when flooded by exceptionally high tides. Feeding intensities were consistently high at farm sites for both species. In Part 3, 23 mallards and 40 American wigeon were shot while feeding in estuarine locations commonly used for feeding. Analysis of gullet contents revealed that both species ate a wide variety of items. Main foods were, for mallards, seeds, invertebrates and green algae and, for American wigeon, green algae, roots, seeds and green vegetation. Algae and marine Invertebrates are not usually considered to be important dabbler foods in estuaries. Major conclusions and recommendations are: 1) Both farm and coastal sites are important to dabblers, with fields being favoured as feeding locations under good flood conditions and coastal habitat being vital during dry or freezing periods. As dabblers move among sites, assessment and management of wintering dabbler habitat should be by wetland complexes rather than by individual estuaries. 2) Dabblers feed in or near shallow water. Fields that do not flood are not worth maintaining as dabbler habitat. Assessment of estuarine marshes should consider the availability of food at all points of the tidal cycle. 3) As both species feed on a wide variety of items, factors affecting shallow water flooding and thus food availability are more important than plant species composition. 4) Marine deltas and beaches are important as refuges from disturbance and as feeding grounds. They form an integral part of dabbler coastal habitat. / Science, Faculty of / Zoology, Department of / Graduate

Acorns of red oaks (Quercus spp; Subgenus Erythrobalanus) are important forage for wildlife and seed for oak regeneration. I estimated production of viable acorns by red oaks in 5 forests in the Mississippi Alluvial Valley (MAV) and 2 greentree reservoirs (GTRs) in Mississippi. Mean acorn production in the MAV was 439 kg(dry)/ha of red oak crown (CV = 29%) during autumn-winter 2009-2010 and 794 kg/ha (CV = 19%) in GTRs during autumn-winters 2008-2010. I recommend researchers sample acorn production in the MAV for ≥5 years to improve precision of estimates (i.e., CV ≤ 15%). I estimated mass and gross energy (GE) of viable red oak acorns after 90 days in unflooded and flooded hardwood bottomlands in Mississippi. Within species, mass loss of acorns was <8.4% and variation in GE ≤0.08 kcal(dry)/g. Winter decomposition of intact viable red oak acorns would have minimal effect on wildlife carrying capacity of hardwood bottomlands.

Master of Science

Large scale disruption of natural habitats worldwide has led to concern over the effects of habitat fragmentation on wildlife populations. Small scale experiments may be a useful tool for discovering effects of fragmentation over larger landscape scales. I sought to explore the potential for using voles as an experimental model system, at a small scale, to discover mechanisms that may affect other species at different spatial scales. I compared over-winter demography of gray-tailed voles, Microtus canicaudus, in two experimental landscapes, consisting of fragmented and continuous habitat, to assess the effects of habitat fragmentation. I chose winter as the time frame of the experiment because it poses harsh conditions for voles and because seasonal bottlenecks may affect population persistence. Population size, population growth rates, reproduction, recruitment, survival and movements, were monitored using mark-recapture methods in 8, 0.2-ha enclosures planted with alfalfa. The habitat within the enclosures was manipulated into 2 configurations of equal area, 1 large continuous patch (625 m��), and a mosaic of 25 small patches (each 25 m��), prior to the introduction of 12 pairs of animals/enclosure. I hypothesized that population size and growth rates, reproduction, recruitment, and survival would be greater for vole populations in continuous habitats than for populations in fragmented habitats. Additionally, I hypothesized that movements would be more restricted within fragmented habitat because the voles would perceive the area between habitat patches as a barrier. I did not detect significant differences between vole populations in continuous and fragmented treatments. However, populations residing in fragmented habitat showed higher variability over the study period. Populations in both treatments decreased throughout the winter period and all became extinct by the end of the study. Reproduction occurred only during the fall period, and there were no significant differences between treatments. Movements were not different between treatments, or between male and female voles, but movements did increase over time. Survival appeared to be higher for male voles in continuous habitat than in fragmented habitat, but female vole survival was similar between treatments. Survival was influenced by weather conditions, and predation. These results contrast with a previous experiment during the summer season, and indicate that seasonal bottlenecks may be important to consider when studying habitat fragmentation. Extinction of populations in both treatments demonstrates that small populations are extremely vulnerable to both environmental and demographic stochastic events. / Graduation date: 1997

Dans une ville de Vilnius, la structure et la division des populations d’oiseaux hivernants étaient faites des recherches en 2003 – 2005. Ainsi que dans les étangs des régions de Neris, Vilnelė et de Žvėrynas. Pendant la période des recherches les neuf espèces d’oiseaux migrateurs étaient aperçues: le canard colvert, le harle bièvre, la mouette rieuse, la poule d’eau, le fuligule milouin, le garrot à œil d’or, le grèbe huppé, le foulque macroule, le cygne muet. Pendant des recherches de différents saison dans toutes les gisements d’eau de Vilnius on rencontre le plus souvent le canard colvert et le harle bièvre. La mouette rieuse était trouvée aussi dans toutes les gisements d’eau, mais l’abondance de la mouette rieuse s’accroîssait seulement pendant la période de la migration d’été. Le plus grandes agglomérations des canards colverts on trouve dans les étangs de Žvėrynas, Vilnelė et à coté de la région d’Antakalnis. Dans ces endroits les canards sont nouris toujours. Des endroits pour hiverner le plus importants pour le harle bièvre sont dans une rivière Neris à coté d’un parc Vingis, à Vilnelė et à Neris à coté de la région d’Antakalnis. Pour appréciér l’abondance des oiseaux en 2003 – 2004 et en 2004 – 2005 pendant des saisons d’hiver l’abondance de la population a changé seulement du harle bièvre: en 2004 – 2005 en hiver la population de cette espèce d’oiseaux était plus petite que en hiver dernièr.