Orientador: Woodruff Whitman Benson / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T11:22:08Z (GMT). No. of bitstreams: 1 Sobral-Souza_Thadeu_M.pdf: 2228457 bytes, checksum: 1bafa7e233e5df09e117aab4299abb4c (MD5) Previous issue date: 2011 / Resumo: A ecologia de populações busca entender a variação na abundância das espécies no tempo e no espaço. Espécies que possuem ciclos de vida de curta duração, como a maior parte dos insetos, se tornam especialmente convenientes para essa finalidade. Este estudo examinou os padrões de abundância durante o ano 2009 de uma borboleta tropical próximo ao limite de sua distribuição geográfica, no sudeste do Brasil, em uma localidade subtropical. Neste trabalho, Heliconius sara apseudes foi estudada ao longo de uma estrada no Vale do Rio Quilombo, próximo à cidade de Santos, SP, Brasil, usando a metodologia de captura, marcação, liberação e recaptura (CMLR). Foram marcados 498 indivíduos de Heliconius sara (378 machos e 120 fêmeas) sendo 27,7% destes recapturados. Em 2009, indivíduos adultos de ambos os sexos apareceram na área na última semana de abril, sendo que os machos tiveram pico no início do mês de maio enquanto as fêmeas no fim do mês de abril. Os machos sempre foram muito mais abundantes que as fêmeas, independente da parte da estrada e da época do ano. Durante abril, plantas floridas, que servem de alimento para os adultos, eram abundantes. A abundância de adultos se manteve alta de abril a julho, seguido por um período de crescente raridade até sumir da área no início de outubro. Espacialmente, a abundância de H. sara foi maior na unidade demográfica 2 (final da estrada), próxima à serra, quando comparada com o início. A atividade, número de indivíduos voando, foi maior no final da estrada do que no início. Indivíduos marcados em diferentes segmentos da estrada se mostraram altamente residentes (96%). Os poucos que se dispersaram mais que 100 m (6 entre 138 recapturas) eram machos. O tempo médio de permanência no local foi de 18,8 dias para recapturas, com uma permanência máxima de 86 dias para machos e de 44 dias para fêmeas. Por fim, o comprimento da asa anterior (CAA) das fêmeas foi superior (2mm) ao dos machos. Diferente de H. sara de populações de Carajás - PA e de Linhares - ES que apresentam adultos ativos o ano inteiro, a população do Vale do Rio Quilombo aparentemente recruta de forma concentrada no mês de abril e some sem vestígios em outubro, ou mantêm populações baixas ou persiste em refúgios ecológicos sazonais / Abstract: Population ecology seeks to understand the variation in species abundance in time and space. Species that have life cycles of short duration, like most insects, is especially convenient for this purpose. This study examined patterns of abundance during one year in a tropical butterfly near the limit of geographical distribution, in southeastern Brazil, in a subtropical location. In this work, Heliconius sara apseudes was studied along of road in the Quilombo River Valley, near of Santos' city, SP, Brazil, using the method of capture, marking, release and recapture. 498 individuals were marked (378 males and 120 females) being 27.7% of those recaptured. In 2009, individuals of both sexes appeared in the last week of April, and the males had peaks in the beggining of the month of May while the females at the end of April. Males have always been much more abundant than females, regardless of road part and of the season. During April, flowering plants, which provide food for the adults were abundant. The abundance of adults remained high from April to July, followed by a period of rarity increasing until disappear in the area in early October. Spatially, the abundance of H. sara was higher in the second demographic unit (final Road), near the mountains, when compared with the beginning. The activity, number of individuals flying, was bigger in the end of the road than at the beginning. Individuals marked in different segments of the road were shown highly residents. The few that were dispersed more than 100 m (6 of 138 recaptures) were males. The average length of stay in place was 18.8 days for recaptures, with a maximum stay of 86 days for males and 44 days for females. Finally, the length of forewing of females was higher (2mm bigger) than the males. There was an increase in the size of the wings of males advancing years, perhaps due to better survival of larger butterflies. Different of H. sara populations further north that have active adults throughout the year, the population of Quilombo River Valley apparently recruits in concentrated form in April and disappears without a trace in October, or maintaining low populations or persisting in seasonal ecological refuges / Mestrado / Ecologia / Mestre em Ecologia

Charles University, Faculty of Science Institute for Environmental Studies Doctoral study programme: Environmental Sciences Summary of the Doctoral thesis Impact of Climate Change on Czech Bird Populations Vliv klimatické změny na ptačí populace v České Republice Mgr. Tomáš Telenský Supervisor: doc. Mgr. Jiří Reif, Ph.D. Prague, 2018 Abstract Climate change is one of the most important drivers of biodiversity. If it proceeds at current pace, it will lead to homogenization and pose a serious threat to biodiversity. Birds, as one of the most researched taxonomic groups, are successfully used as indicators of biodiversity of the whole ecosystems, and thus offer an excellent opportunity to study the overall impact of climate change. We use data from repeated annual monitoring programmes in Czech Republic, Breeding Bird Monitoring Programe, based on point counts, and Constant Effort Sites mist- netting ringing programme, capture-mark-recapture schema. We found that: 1. Population growth of 6 out of 37 resident species responded negatively to seasons with lower winter temperatures. The response was stronger in species feeding on animals. 2. Long-distance (LD) migrants' breeding productivity responds negatively to higher spring temperatures and advanced spring as indicated by earlier leaf unfolding of three tree...

The alfalfa weevil, Hypera postica (Gyllenhal) (Coleoptera: Curculionidae), remains a serious pest in Virginia despite being under complete biological control in the northeastern U.S. In 1996, a survey of 187 alfalfa fields in Virginia was initiated to determine the current pest status of alfalfa weevil and incidence of natural enemies. Fields located in the Piedmont region of the state had significantly higher alfalfa weevil pressure than those in the Shenandoah Valley and southwestern region. The dominant natural enemy of alfalfa weevil larvae was the parasitoid, Bathyplectes anurus (Thomson). Larval parasitization was lower in the Piedmont compared with the other regions. The entomopathogenic fungus, Zoophthora phytonomi, also killed weevil larvae in all regions. A more intensive ecological investigation of alfalfa weevil population dynamics and mortality was initiated in 1997 to determine why H. postica remains a pest in Virginia, particularly in the Piedmont region. Nine alfalfa weevil populations from three geographic locations were sampled and measured over a period of two years. Results showed that warmer winter temperatures in the Piedmont region contributed to a higher rate of alfalfa weevil oviposition compared with the Shenandoah Valley and southwestern mountains. Parasitization of adult weevils by Microctonus aethiopoides (Loan) was low in all regions of Virginia relative to rates reported in the northeastern U.S. This also contributes to relatively high alfalfa weevil fecundity in Virginia because a greater percentage of adults reproduce. Phenological asynchrony between M. aethiopoides and the alfalfa weevil may explain the low parasitism. The 1st generation of M. aethiopoides adults did not emerge until most of the overwintering alfalfa weevil adults had reproduced and died. A majority of alfalfa weevil eggs were laid before January at all locations in Virginia. Approximately half of the egg population survived to contribute to spring larval infestations. In the northern U.S., very few alfalfa weevil eggs survive the winter, and larval populations result primarily from spring-laid eggs. Mortality of larvae was high in Virginia and comparable to that reported in other states. Bathyplectes anurus was well-synchronized with alfalfa weevil and killed a high percentage of larvae. / Ph. D.

Doctor of Philosophy / Department of Biology / Brett K. Sandercock / Greater prairie-chicken (Tympanuchus cupido) populations have been reduced by >70% since the turn of the 20th century due to large-scale conversion of native prairie habitats to cultivated agriculture and other human development. Although Kansas is considered a stronghold for greater prairie-chickens, statewide populations have declined >30% in the last 30 years. Goals of this dissertation were to determine the demographic mechanisms for apparent population declines and evaluate how regional variations in landscape composition and grassland management affect the demography, habitat use, life-history, and population viability of three populations of greater prairie-chickens. First, I found that, despite high reproductive potential, poor reproductive success prevented populations from being self-sustaining. All three populations were projected to decline but finite rates of population declines were different among populations (λ = 0.49, 0.54, and 0.74). I found that grassland fragmentation and rangeland management practices influence nearly every aspect of greater prairie-chicken population ecology and dynamics. A population in a contiguous prairie landscape managed with annual spring burning and intensive early stocking of cattle (South) was characterized by delayed breeding, low nest and brood survival (0.08–0.18 and 0.27, respectively), high annual survival of mature females (0.64–0.71), projected age-ratios heavily skewed toward adults, and longer generation times. Conversely, a population in grasslands heavily fragmented by cultivation and managed with longer fire-return intervals and moderate grazing (Smoky) initiated nests earlier, had higher nest and brood survival rates (0.16–0.31 and 0.34, respectively), produced significantly larger eggs, and had low annual survival (0.34–0.42) and shorter generation times. A site with intermediate levels of fragmentation, burning and grazing (North) had intermediate demography. Finite population change was more sensitive to changes in adult survival at all sites, but the relative influence of fecundity parameters on projected population change was not similar among study populations. Data indicate that differences in rates of decline among populations were largely due to variation in adult survival mediated by human landscape alteration. Human-mediated changes to grasslands impact the demography and viability of prairie-chicken populations, influence population sensitivities to changes in vital rates, and mediate changes in the life-history strategies of a grassland-sensitive species.

Thesis (PhD (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / The Okavango Delta, Botswana, is a unique ecosystem and this is reflected in its extraordinary biodiversity. The Nile crocodile (Crocodylus niloticus Laurenti) is the apex predator, and performs a number of vital functions in this system, making it a keystone species. The panhandle crocodile population has declined significantly over the last 80 years and is now threatened as a result of past over-exploitation and present human disturbance. In order to effectively conserve this species and in turn the health of this important region it is imperative to gain an understanding of their ecology and population dynamics. The population status of the Nile crocodile in the panhandle region of the Okavango Delta, Botswana, was assessed using a combination of capture-mark-recapture surveys, spotlight surveys and aerial surveys. The capture-mark-recapture experiment was conducted continuously from 2002 - 2006. A total of 1717 individuals, ranging in size from 136 mm – 2780 mm SVL, were captured, of which 224 animals were recaptured. Using a Bayesian technique, the total annual population in the panhandle region of the Okavango Delta was estimated to be 2 570 ± 151.06 individuals, with an adult population of 649.2 individuals with the number of breeding females estimated to be 364 individuals. It was concluded that this population cannot sustain the further harvest of breeding animals prior to the increase and stabilization of the population. Spotlight counts revealed a decline in the encounter-rate of crocodiles on the Okavango River with time, although more long-term data needs to be collected to confirm this trend. During the low-water season (September - February), 22.34 % of all crocodiles were observed, while during the flood-season only 13.34 % were observed, yielding correction factors for spotlight surveys of 4.46 (low-water) and 7.49 (high-water) for all animals in the panhandle. Two aerial surveys, conducted at the low-water and high-water peaks yielded total estimates of 588 (77.7 % of adults) during the low-water period and 350 (56.7 % of adults) during the high-water period. Correction factors of 1.28 (low-water) and 1.77 (high-water) were calculated for aerial surveys. An annual average of 50 nests was located in the panhandle, representing a 50 - 60 % decrease over the last 20 years. In regions with high human disturbance, breeding females situated their nests in hidden locations, away from accessible channels. Hatchlings exhibited elongation of the jaw in order to capture smaller prey items and morphometric shifts in jaw shape coincided with a dietary change at 400 mm SVL. The jaw became broader and deeper as animals matured, presumably in preparation for larger mammalian prey. The average growth rate of recaptured yearlings was 0.198 ± 0.116 mm.d-1 SVL and was closely correlated to the amount of time an individual spent in above-average water temperatures. Body condition (RCF) was significantly and positively correlated with a rise in water-level and negatively correlated to time spent in above-average water and air temperatures. Average RCF values were intersected when animals had spent 50 % of their time in above-average temperatures and water level. Generally crocodiles in the panhandle showed no significant sex-related differences in their sizes or the distances they travelled. The majority of recaptures (62.5 %) moved less than 500 m from the initial capture site. Adults in the panhandle occupied definite ranges, within which were preferred core areas where the majority of their time was spent. The panhandle crocodile population has declined significantly over the last 80 years, and is now threatened as a result of past over-exploitation and present human disturbance. The management of this population, including both its conservation and sustainable commercial utilisation, requires an adaptive strategy based on accurate monitoring procedures.

This study investigates the reproductive strategies of the pill-box crab, Halicarcinus cookii on the Kaikoura Peninsula, New Zealand. Various aspects essential to understanding reproductive strategies were examined including growth, population dynamics, reproductive biology and mating behaviour. H. cookii exhibits obvious sexual dimorphism such that females develop wide abdomens forming brood chambers, and males tend to grow larger than females and have larger chelipeds in relation to body size. H. cookii allocates energy into growth and reproduction in separate phases of its life cycle where growth ceases as reproductive maturity begins due to a terminal/pubertal moult. Despite the presence of ovigerous females throughout the 15 month sampling period, the population was highly seasonal, with peaks in recruitment and growth occurring primarily during the winter months and peaks in numbers of mature individuals during the summer months. Reproductive output increased with body size in H. cookii, as larger females produced more eggs and larger males transferred more sperm than their smaller counterparts. Ovaries matured prior to the terminal/pubertal moult (anecdysis) and, in multiparous females, in synchrony with brood development, allowing females to produce broods in quick succession, maximising their reproductive output in their short life span (approximately 12-18 months, 6 months as an adult). Incubation duration of broods decreased as seawater temperature increased, suggesting that temperature is the primary cause of the seasonal population cycling. Sperm storage allowed females to produce at least 4 fertilised broods without re-mating. Some sperm mixing in the spermathecae appeared to occur and the ventral-type structure implies last male sperm precedence. Males therefore preferentially mated with females closest to laying a new brood and guarded them longer than other females to ensure their paternity. Guarding duration varied according to the sex ratio allowing males to maximise their reproductive output.

This thesis examines the ecology, parasites and pathogens of three insectivorous bat species in Wytham Woods, Oxfordshire; Myotis nattereri (Natterer’s bat), M. daubentonii (Daubenton’s bat) and Plecotus auritus (Brown long-eared bat). The population structure was assessed by monitoring associations between ringed individuals, utilising recent advances in social network analysis. Populations of both M. daubentonii and M. nattereri were found to subdivide into tight-knit social groups roosting within small areas of a continuous woodland (average minimum roost home range of 0.23km2 and 0.17km2 respectively). If this population structure is a general attribute of these species it may make them more sensitive to small scale habitat change than previously thought and has implications for how diseases may spread through the population. M. daubentonii had a strong preference for roosts close to water, away from woodland edge and in areas with an easterly aspect. The factors driving roost choice in M. nattereri and P. auritus remain elusive. The segregation of M. daubentonii into bachelor and nursery colonies was not a result of the exclusion of males from roosts close to water by females, or variation in microclimate preferences between the sexes, as was predicted. Body condition (weight/forearm length) was correlated with host characteristics including age and reproductive status, and weather variables. Astroviruses and Coronaviruses, which have characteristics typical of zoonotic viruses, were identified in UK bat species for the first time. Coronaviruses identified formed species-specific clades while Astroviruses were highly diverse. Though not closely related to human viruses these are potential zoonotic diseases of the future. Models of Coronavirus and ectoparasite distribution suggest individual attributes (e.g. sex and age) and population structure (e.g. the formation of nursery and bachelor colonies) are important predictors of parasite and pathogen prevalence. This study characterises a system that offers many opportunities for future research including studies of sociality, disease modelling and conservation management.

Mathematical modeling of population dynamics can provide novel insight to the growth and dispersal patterns for a variety of species populations, and has become vital to the preservation of biodiversity on a global-scale. These growth and dispersal stages can be modeled using integrodifference equations that are discrete in time and continuous in space. Previous studies have identified metrics that can determine whether a given species will persist or go extinct under certain model parameters. However, a need for computational tools to compute these metrics has limited the scope and analysis within many of these studies. We aim to create computational tools that facilitate numerical explorations for a number of associated integrodifference equations, allowing modelers to explore results using a selection of models under a robust parameter set.

Population biology and ecology of the species Phyteuma orbiculare L. Abstract This diploma's thesis deals with Phyteuma orbiculare L. (Round-headed Rampion) from family Campanulaceae. According to the law (MŽP ČR 395/1992 Sb.) the studied species is classified as a seriously endangered species of the Czech flora. Two of its distinguished subspecies (subsp. montanum and flexuosum) are on the Red list of vascular plant species (Procházka 2001) of critically endangered species. One of the outputs of this thesis are grid maps of all localities of the species in the following time intervals: until 1949, 1950 - 1989, 1990 - 1999 and 2000 - 2010. As information sources about location of P. orbiculare I used herbaria collections, literature, botanical databases, and Protected Landscape Area Administrative reports. Some data were obtained from botanical experts and some from my personal field-work. One of the main results of thesis is comparison of the distribution of historical and recent localities of the species. I studied chemical composition of soil, species composition and number of flowering plants amount of populations in 21 recent and 19 historical localities in Czech Republic. Recent localities are richer in species and poorer in nutritive substances than the historical localities. Number of flowering...

Master of Science / Department of Biology / David C. Hartnett / Invasive plants pose a global threat by changing natural communities and ecosystems in ways that may be irreversible. Marrubium vulgare L. (horehound), native to Eurasia, is an invasive exotic plant found throughout the United States. Little is known about M. vulgare in the U.S. and this study aimed to understand the basic biology, habitat, and population dynamics of M. vulgare in its invasive habitat as well as the role of disturbance in the invasions. Wind Cave National Park (WCNP), an area comprising ponderosa pine and mixed grass prairie vegetation types, was used as the site for this study. In a GPS and GIS mapping study, M. vulgare was found to be significantly associated with prairie dog towns, an Aristida purpurea - Dyssodia papposa (threeawn and fetid marigold) vegetation community (a vegetation type found exclusively on prairie dog towns), and certain types of loamy soils. M. vulgare was rarely found off of prairie dog towns and then only in other disturbed areas such as bison trails or tree falls. Population studies showed M. vulgare populations were mostly stable or slightly decreasing in density (though not significantly) from 2010 to 2011; however, a few of the populations did increase dramatically in density from 2010 to 2011. M. vulgare populations existed in high densities (78.3-322.9 ramets/m2) and in low densities (0.1-2.2 genets/m2) throughout WCNP. Disturbances including prairie dog burrows, bison trails, prairie dog and bison presence, mowing, and percent cover of bare ground were measured in relation to population dynamics. While M. vulgare populations were disturbance dependent, there was no clear relationship between disturbances and population dynamics. Examination of M. vulgare life history traits found that while M. vulgare had relatively low biomass allocation to reproduction as compared to native perennial prairie species, M. vulgare produced an extremely high number of small seeds (estimated 1487/plant). Seedling establishment rates were also high. While not quantified, M. vulgare appears to be effectively dispersed through bison epizoochory. These results help to inform management of M. vulgare populations: minimizing disturbance, decreasing propagule supply, and minimizing dispersal may help to reduce M. vulgare invasions.