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Projected increases in Africa's human population over the next 40 years point to further, large-scale conversion of natural habitats into farmland, with far-reaching consequences for raptor species, some of which are now largely restricted to protected areas (PAs). To assess the importance of PAs for raptors in Uganda, we conducted an annual road survey through savanna, pastoral and agricultural land during 2008-2015. Here, we present density estimates for 34 diurnal raptor species, 17 of which were encountered largely or entirely within PAs. These included seven out of eight globally threatened or near-threatened species surveyed. Based mainly on published demographic values, we converted density estimates (birds 100 km−2) to numbers of adult pairs, for 10 resident, savanna-dependent species. We then estimated adult population sizes within conservation areas (individual PAs and clusters of contiguous PAs), based on the area of savanna in each site. This suggested that two threatened residents, Martial Eagle Polemaetus bellicosus and Lappet-faced Vulture Torgos tracheliotos, have national breeding populations of just 53-75 and 74-105 pairs, respectively. A third species, White-headed Vulture Trigonoceps occipitalis, may have a breeding population of just 22-32 pairs. In each case, at least 90% of pairs are thought to reside within Uganda's five largest conservation areas. In three cases our estimates of pair density were markedly lower than in other studies, while in six cases they were broadly consistent with published findings, often derived using more intensive survey methods. Further work is required to determine the accuracy of our estimates for individual conservation areas, and to assess the long-term viability of Uganda's threatened raptor populations. [ABSTRACT FROM AUTHOR]

Long-term studies of urban birds are relatively scarce, especially in Africa. We analysed trends in species richness and bird species occurrence over a 32-year period in Kampala, Uganda, in order to assess changes in the bird community in a period that has shown rapid expansion of the city's human population. Given that species may respond to urbanisation according to their diet, we also analysed bird community trends of species groups defined according to predominant diet. There was an overall decline in species richness that was largely driven by declines in insectivores and granivores. General declines were evident also when the trends in the most common individual species in these two groups were considered. The occurrence of the commonest predator and scavenger species tended to increase over the period considered. Insectivorous species are likely to be especially affected by increasing urbanisation due to air pollution. Predators and scavengers are likely to have benefitted from the inability of municipal waste management to keep pace with growth in the human population, hence providing more potential food resources. Both insectivores and predators/scavengers are therefore good candidates for the development of urban indicators. [ABSTRACT FROM AUTHOR]

In recent decades, Marabou StorksLeptoptilos crumeniferushave become common in many urban centres, including Kampala, Uganda, where, as of 2016, they number several thousand birds, with more than 1 200 breeding pairs. Elsewhere in Uganda, the majority of colonies are also in towns and villages. Traditionally, a bird of savannas, breeding in those areas is timed so that the growing young are in the nest during the December to February drier period, when food for scavengers is expected to be more abundant. In southern Uganda, most colonies start each season around November, and this was originally the case in Kampala. However, in recent years, nesting has begun several weeks earlier for the majority of pairs, and up to four months earlier for a smaller group. The main diet of Marabous in Kampala is human refuse, which is available all year round, so in principle they could nest at any time. However, they do not do that. In ‘natural’ ecosystems, breeding at the ‘wrong’ time would probably be disadvantageous, resulting in large young in the nest during rainy periods, a time of food scarcity. Thus, within the traditional nesting season, earlier nesters produce more young. It is not yet clear whether the very early nesters in Kampala also produce more young than the main group. Further understanding of this unusual situation will benefit from continued studies in future years. [ABSTRACT FROM PUBLISHER]

Capsule Timed species counts could provide a more valuable bird survey tool in the humid tropics than previously suggested. Aims To compare the relative performance of two bird survey methods that differ in complexity – point counts with distance sampling; and timed species counts – for estimating the species richness and abundance of bird species in tropical farmlands. Methods Twenty-six sites were surveyed in banana–coffee farmland habitats north of Lake Victoria, central Uganda. Point counts and timed species counts, each lasting ten minutes, were conducted at ten stations in each site. Results The two methods provided similar estimates of species richness in farmland and a significant positive correlation between measures of frequency of occurrence of bird species from the two methods was found. There was also a significant positive correlation between density from point counts with distance sampling and frequency of occurrence of bird species from the ten-minute counts. Ten-minute counts tended to accumulate bird species faster than point counts but this difference was not significant. Conclusions In these relatively open farmland habitats species richness estimates from both methods were not significantly different. Although density can only be derived from point counts these densities were highly correlated with frequencies from the ten-minute counts. The frequency of occurrence method is much quicker and simpler, in terms of both field methods and analysis, because it does not involve distance estimation. The results presented here suggest that, at least in relatively open habitats, frequency of occurrence provides a valuable index of density of birds. [ABSTRACT FROM AUTHOR]

For a large number of threatened bird species, no information on habitat requirements or population estimates are available. We show for one of the least-studied African birds, the Oberländer's Ground-Thrush Zoothera oberlaenderi, how a first assessment of its habitat preferences and population size can be done if a short-term census is combined with a GIS-based species-habitat analysis. Between 9 February and 14 March 2008, we made intensive field surveys, using point counts and mist-netting in Semliki and Bwindi Impenetrable National Parks (BINP), two forests in Uganda from which there are previous records. While the species was not recorded in Semliki, eight were heard singing in BINP. We made the first analysis of this species' habitat preferences by analysing all records of the species with variables extracted from GIS layers for the BINP. It preferred dense forest types, close to rivers and at elevations of 1 500-1 935 m. Using detailed habitat information we calculated 30 km2 of suitable habitat (out of the 331 km2 in BINP), which could hold an estimated minimum of 36-45 males. Because there is on-going forest degradation and deforestation within its potential distributional range in Uganda and the Democratic Republic of the Congo, and because the population in Uganda appears so small, there is a need to reconsider the IUCN Red List category of the Oberländer's Ground-Thrush, which is currently Near Threatened. [ABSTRACT FROM AUTHOR]

The globally Vulnerable Grey Parrot (Psittacus erithacus) has been seen in Kampala, Uganda’s capital city, in increasing numbers in recent years. This apparently new behaviour of a typically forest species is helped by the presence of many large trees, which provide roosting and nesting sites, and fruiting trees where they feed. Grey Parrots in Kampala potentially come from three sources: escapees, releases of captive birds or wild birds moving into a suburban environment. Birds mostly exhibit behaviours typical of wild birds, but as most, if not all, of the Grey Parrots in captivity are wild-caught and would revert to wild-caught behaviours when released, it is difficult to distinguish them from the wild population. However, we believe that at least some of the birds seen in Kampala are wild. [ABSTRACT FROM PUBLISHER]

Comments on implications of bird conservation for biodiversity conservation in South Africa. Measures of bird biodiversity; Enumeration of things for consideration in using biodiversity data for conservation planning; Effect of species diversity on habitat diversity.