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The paper provides a detailed overview of population dynamics and trends in the Arab region. Furthermore, it explains the concept of demographic dividend and timing of the window of opportunity. With a view to enable countries in the region to reap the benefits of the changing population structure, the window is calculated for each country. The last part of the paper presents four case studies of countries that benefitted from their demographic dividend.

Farmland bird populations in Europe have been in decline for a long time. Agricultural intensification and growing a large share of crops that provide suboptimal breeding habitat could be the main causes of the observed decline. To explore these possible drivers, I focused on population trends of farmland bird species in different habitats in the Czech Republic over the periods 1982-1990 and 1990-2010. Specifically, I focused on the variability in trends within each species in respect to the differences in landscape management between the lowlands and mid-altitude areas before and after 1990. The expected effect of intensive farming in the lowlands until 1990 was reflected by a strong decline in populations of Northern Lapwing and Yellowhammer. The influence of less intensive farming in mid-altitude areas causing moderate population decline was confirmed rather by shrubs and trees species than farmland specialists. After 1990, less intensive farming in the lowlands should reduce the decline, which may have occurred, but compelling comparison of population trends between the two time periods was not possible for most species due to the lack of data. On the contrary, more intensive population decline in mid-altitudes after 1990, which should be the response to arable land abandonment, was not...

Thesis (Ph. D.)--Cornell University, 1976. / Vita. Includes bibliographical references (p. 290-310).

Thesis (Ph. D.)--Cornell University, 1976. / Vita. Includes bibliographical references (p. 290-310).

The thesis presents data from butterfly transects monitoring, carried out for 7 years on 36 transects established both within nature reserves and unprotected landscapes throughout the Czech Republic and walked three times a month between April and September. Only seven transects were monitored for the whole monitoring period. There were 192 771 individual butterfly records on 127 species of butterflies and burnet moths, i.e. 76.5% of the Czech fauna of the targeted groups). Data on their abundances are for the first time available for the Czech Republic. The distribution of individual species abundances approximated a lognormal model. The abundant species were generalists of non-wooded habitats, which prosper in the intensively managed landscapes of the Czech Republic. Trends of abundance, determined by the TRIM program, were estimable for 92 species. Over the monitored period, the relative abundance of nine species significantly decreased, while those of of seven species significantly increases. The remaining 76 did not display unequivocal trends, but still, 17 are likely increasing and 29 likely decreasing. Comparing the trends with the life history and bioclimatic traits of the butterflies showed that species whose abundance did not change possess traits typical for generalist butterflies (mobile species, overwintering in later life stages, longer flight period etc.), while decreases were more common among thermophilic species. Splitting the analyses for data originating from reserve vs. unprotected areas suggested that mesophilic species and species of more advanced successional stages prosper outside of reserves, whereas thermophilic species tend to decline there, and that an opposite pattern applies to reserves. I discuss recommendations for future of the monitoring Czech butterfly monitoring scheme.

Understanding how climatic variation affects animal populations and communities is essential for addressing threats posed by climate change, especially in systems where impacts are projected to be high. We evaluated abundance dynamics of five common species of diurnal lizards over 25 years in a Sonoran Desert transition zone where precipitation decreased and temperature increased across time, and assessed hypotheses for the influence of climatic flux on spatiotemporal variation in abundances. We repeatedly surveyed lizards in spring and summer of each year at up to 32 sites, and used hierarchical mixture models to estimate detection probabilities, abundances, and population growth rates. Among terrestrial species, abundances of a short-lived, winter-spring breeder increased markedly by an estimated 2375285% across time, while two larger spring-summer breeders with higher thermal preferences declined by up to 64%. Abundances of two arboreal species that occupy shaded and thus sheltered microhabitats fluctuated but did not decline systematically. Abundances of all species increased with precipitation at short lag times (151.5 yrs) likely due to enhanced food availability, but often declined after periods of high precipitation at longer lag times (254 yrs) likely due to predation and other biotic pressures. Although rising maximum daily temperatures (Tmax) are expected to drive global declines of lizards, associations with Tmax were variable and weak for most species. Instead, abundances of all species declined with rising daily minimum temperatures, suggesting degradation of cool refugia imposed widespread metabolic or other costs. Our results suggest climate warming and drying are having major impacts on lizard communities by driving declines of species with traits that augment exposure to abiotic extremes and by modifying species interactions. The complexity of patterns we report indicate that evaluating and responding to the influence of climate change on biodiversity must consider a broad array of ecological processes.

This diploma thesis is focused on overpopulation problem, which is a very debatable term in this time. The thesis analyzes recent development in fertility, mortality and migration in each continent with aim to evaluate threats of the overpopulation. Although this term is more like global problem, the thesis aims to specify and identify continents, which might be truly affected by overpopulation. Part of the diploma thesis is focused on calculation of possible future development of population size based on mathematical models which are birth - immigration - death process and logistic (Verhulst) growth. The projections are established on UN data and their horizon is period 2095 - 2100.

Translocations have been used as a management strategy to successfully augment declining native wildlife populations. Greater sage-grouse (Centrocercus urophasianus; sage-grouse) population declines on Anthro Mountain, Utah prompted managers to translocate sage-grouse and test protocols from a successful translocation project in Strawberry Valley, Utah. Sage-grouse from Parker Mountain, Utah were used as the source population for Anthro Mountain and Strawberry Valley translocations. Sixty hens were translocated to Anthro Mountain in 2009 and 2010; I monitored vital rates of the 60 translocated hens and 32 resident hens from 2009-2012. My objective was to determine the overall success of the translocation 4 years after the initial release and compare vital rates to the source population and Strawberry Valley.In Chapter 2, I determined that survival varied by study area and hen age but was not affected by residency status. Annual survival of Anthro Mountain hens was lower than Parker Mountain and Strawberry Valley hens. Adult hen survival in all three populations was higher than yearling survival.In Chapter 3, I determined that the translocation contributed to population growth. Adult resident and previously translocated hens had the highest reproductive success, followed by resident yearlings, newly translocated adults, and newly translocated yearlings. Lek counts increased from 2009-2013 and a new lek was discovered in 2011. Survival was not affected by residency status or age, but varied greatly by year and season. Mean monthly survival was lowest in the fall; this differs from range-wide trends.In Chapter 4, I determined that translocated hens adapted to the release area. They exhibited similar seasonal movements and used similar habitats as residents. The home range size of resident and translocated hens was comparable; however, previously translocated hens had smaller home ranges than newly released hens.Despite landscape level differences between the source and release areas, translocated hens assimilated to the population and contributed to population growth. Although the translocation was successful, the low vital rate estimates are cause for concern. The low estimates suggest that factors such as predation, habitat quality and quantity, and anthropogenic influences may be problematic for this isolated population.

Babblers together with the close related Timallidae are not very common inmates of the zoological gardens. In the Czech Republic they are only bred in the zoological gardens in Ohrada, Pilsen and Prague. The breeding in the zoological gardens is not generally very successful. The zoo in Prague with its number of species owns the largest collection of these birds in Europe. In the past the breeders in Prague were the first ones in Europe who managed to raise for example Rufous-fronted Laughingthrush, Sunda Laughingthrush, Barred Laughingthrush or Sumatran Laughingthrush (Black-and-white Laughingthrush). As the first ones in the Czech Republic they were able to reproduce the critically endagered Blue-crowned Laughingthrush (Courtois's Laughingthrush). The Blue-crowned Laughingthrush is so rare that for several years it was not clear at all if they still live in nature. In the year 2000 they were rediscovered in the number of 240 pieces. The quantity of them in the zoological gardens all over the world does not exceed 100 pieces. The zoo in Chester does a European breeding book of these pieces. Some birds in Prague reproduce repetitively and they prove that the right method of the breeding was found. Hopefully this method would lead to the birth of the securing population in the care of humans. This securing population is very important for the protection of these birds. The attempt of this work is to assess the links between the results of the breeding and their conditions, the comparison of the nesting activities of the two chosen species of babblers, then the summarizing of the expansion and the results of the breeding of the individual species and also the processing of the expansion, the development of the quantity and the problems of the protection of the babblers in nature. The following facts were found out: the breeding of the birds in the exposition or in its environment does not have an essential influence on their nesting activity. However, for the nesting activity it is more important if they are a newly formed couple or a couple paired for a longer time and at the forest babbler it is the female that has an important role in incubation period. However, at the Sumatran Laughingthrush there is a frequent changing in different time intervals. The work also shows that only 5 species out of 12, that showed the nesting activity, are able to build a nest without the help of the keepers. That can be attributed to their closer relational breeding and also to putting the higher number of artificially reared individuals into the breeding.