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Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Murchison Falls-Albert Delta Wetland System Ramsar Site, declared in 2006, consists of the River Nile from the Murchison Falls up to and including a small part of Lake Albert. Before entering the lake, the river splits into three main channels passing through an extensive delta supporting a papyrus swamp; the Ramsar site also includes the land within a kilometre of the river banks, north and south. Most is within Murchison Falls National Park. The river, including the channels through the papyrus, supports large numbers of waterbirds of many species. For a year, we undertook monthly waterbird counts along the channels through the delta swamps, and on the section of Lake Albert within the Ramsar site. Overall, we recorded 78 waterbird species and the site regularly supports three globally and another seven nationally threatened species, including Shoebill Balaeniceps rex, Grey Crowned Crane Balearica regulorum and Papyrus Gonolek Laniarius mufumbiri. The site is also important for large numbers of White-winged Black Terns Chlidonias leucopterus on passage. Most of the larger species, such as White-faced Whistling Duck Dendrocygna viduata and Long-tailed Cormorant Microcarbo africanus rarely, if ever breed in this area, instead their numbers drop at the times when they are expected to breed, apparently elsewhere. A number of pairs of Fish Eagles Haliaeetus vocifer breed, and there is a small colony of African Darters Anhinga rufa. The large numbers of easily- seen birds attract increasing numbers of visitors, adding to the site's value. Various industrial activities are planned within the watershed of this Ramsar Site, mainly associated with oil and gas, and our data are expected to provide baseline data for future monitoring of the site. [ABSTRACT FROM AUTHOR]

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]

Short communications Grey Crowned Cranes Balearica regulorum are gregarious rather than social It has long been known that Grey Crowned Cranes Balearica regulorum, in common with most other crane species, are usually seen in pairs - or sometimes several pairs together - and are believed to mate for life (Pomeroy 1980a, Urban et al. 1986). Apart from the few months when they are nesting, Grey Crowned Cranes form flocks, occasionally as many as 2000 in Kenya (Gichuki & Gichuki 1991), but the largest in Uganda are only a few hundreds, and most flocks are much smaller. Almost all cranes in Uganda breed on seasonal wetlands outside protected areas (Olupot et al. 2009), and in southern Uganda they can breed in June and July (Pomeroy 1980a), but all possible wetlands within at least 10 km of the roost have been drained and in many cases, built on. [Extracted from the article]

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]

Copyright of Ostrich: The Journal of African Ornithology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Impacts of urbanization on biodiversity are commonly studied using urbanization gradients which provide a space-for-time substitution in estimating consequences of urban expansion. Rates of urbanization and human population growth are high in tropical countries of the developing world, which also hold most of the world's biodiversity hot-spots, yet few studies have considered biodiversity trends along urban gradients in these regions. Bird communities across a gradient of nine sites in Uganda, from the city centre of Kampala to outlying rural locations, were studied over a six year period. These sites were ordered along an urbanization gradient using Principle Components Analysis based on habitat variables estimated at each site. Bird species richness showed a decrease from rural to urban sites, a trend especially evident in forest birds. There was no clear pattern in total abundance, total biomass or biomass per individual along the gradient. However, this latter result was heavily influenced by a colony of Marabou Storks at one site. When this species was omitted, there was evidence of a positive trend with urbanization, showing that as species richness decreased, the bird community was increasingly dominated by larger species with increasing urbanization, which were mainly scavengers able to exploit human refuse. These results provide further support for the negative impacts of urbanization on species richness, but also demonstrate trends in abundance and biomass are variable across different regions. In particular, the increasing dominance of larger species in urban areas may be relevant to certain geographic and/or socioeconomic contexts. [ABSTRACT FROM AUTHOR]

Cattle Egrets Bubulcus ibis, long known for their expanding geographical range, have in recent years also become increasingly urbanized in Kampala, a city with over 1.5 million people, and elsewhere. First recorded roosting in Kampala over 15 years ago, their numbers now exceed 16000, spread across several sites, at most of which they have also been breeding for several years. However, the numbers nesting are far lower than might be expected from those that come nightly to roost. Breeding in Kampala shows bimodal peaks, perhaps because some birds breed twice a year— which would partly explain their rapid increase in numbers. Timing of breeding is linked to rainfall, but shows more variation between sites and between years than might be expected. Some birds may always have fed in the area that is now Kampala. Today, some feed at the city's main land-fill site, but most go to the countryside where their consumption of bush-crickets, grasshoppers and other insects is presumably beneficial to farmers. Overall, for breeding and roosting, and to some extent feeding, Cattle Egrets can now be considered as urbanized in this near-equatorial city. [ABSTRACT FROM AUTHOR]

During 1998–2011, in an area of western Cyprus spanning about one-quarter of the global breeding range of the endemic Cyprus Warbler Sylvia melanothorax, the species declined at a rate of c.59% decade-1, suggesting that there is an urgent need to review its global conservation status. This decline has coincided with the recent, rapid colonisation of western Cyprus by the Sardinian Warbler S. melanocephala, whose numbers have increased substantially within the study area, as might be expected of a newly colonising breeding species. To identify possible causes of the Cyprus Warbler’s decline we compared its rate of change with measures of land-cover, vegetation density, altitude, rainfall and the presence of Sardinian Warblers at survey sites. The rate of decline in the Cyprus Warbler’s abundance was strongly correlated with land-cover and with the duration of site occupancy by Sardinian Warbler; Cyprus Warbler abundance had declined more steeply on sites colonised by Sardinian Warblers early in the survey period than on sites colonised later. Furthermore, on sites surveyed by BirdLife Cyprus in 2006–2014, Cyprus Warbler abundance had continued to decline significantly (also by c.59% decade-1) in western Cyprus, while Sardinian Warbler abundance had continued to increase. In contrast, Cyprus Warbler abundance showed no significant change in central and eastern Cyprus, where Sardinian Warblers were sparse or absent during the breeding season. These findings are consistent with at least two contrasting scenarios: that changes have occurred in land-cover or climatic conditions in Cyprus, to the detriment of Cyprus Warbler and to the benefit of Sardinian Warbler; or that in western Cyprus at least, the two species may compete for similar resources, despite a lack of evidence of this in an earlier, more detailed study. In either case, we suggest the need for a thorough, nationwide breeding survey of the two species. [ABSTRACT FROM PUBLISHER]

Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30-year Pan-African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, economic, and human costs are already documented. Populations of eight species we assessed had declined by an average of 62%; seven had declined at a rate of 80% or more over three generations. Of these, at least six appear to qualify for uplisting to Critically Endangered. Africa's vultures are facing a range of specific threats, the most significant of which are poisoning and trade in traditional medicines, which together accounted for 90% of reported deaths. We recommend that national governments urgently enact and enforce legislation to strictly regulate the sale and use of pesticides and poisons, to eliminate the illegal trade in vulture body parts, as food or medicine, and to minimize mortality caused by power lines and wind turbines. [ABSTRACT FROM AUTHOR]

Six out of seven vulture species whose global ranges lie largely or wholly within Africa are listed as globally threatened. Since their current distributions individually span up to 39 range states there is a pressing need to develop robust, standardised methods that provide a clear measure of range-wide changes in abundance. Yet, survey methods currently used tend to yield either of two measures: estimates of breeding density, derived mainly from nest counts; or linear encounter rates, derived from road surveys. Here, we present the results of a six-year survey of six vulture species in Uganda, in which we used road counts, in combination with Distance sampling, to determine both encounter rates and densities within protected areas (PAs), and in predominantly pastoral and agricultural areas. In combination, five scavenging species were detected 4–6 times more frequently in PAs than elsewhere, and two species, White-backed Vulture Gyps africanus and Lappet-faced Vulture Torgus tracheliotus, were recorded only within PAs. We estimate that PAs held c.1,300–3,900 individuals of the five scavenging species combined, including c.1,250–2,900 individuals of two Gyps species. We also present national population estimates for two species: White-backed Vulture (c.1,000–2,600 birds) and Lappet-faced Vulture (c.160–500 birds). Although sightings were assigned to only three broad distance bands, Distance sampling provided estimates with a level of precision similar to that achieved for linear encounter rates, but as density estimates; a form more readily comparable with results obtained from other survey types. [ABSTRACT FROM PUBLISHER]

Little is known about bee communities and pollination services conservation strategies in sub-Sahara Africa. A study was conducted at 26 different sites with varying local landscape characteristics in farmlands of central Uganda in 2006. Bees were sampled using coloured pantraps, handnet and line transect counts. Overall 80,883 bee individuals from 6 families and 652 species were encountered. The bee fauna was characterized by a lower diversity of Melittidae and Andrenidae and a high diversity of Apidae, Megachilidae and Halictidae. Megachile and Lasioglossum were the two most species-rich genera. The most abundant species was Apis mellifera adansonii Linnaeus (23 % of total individuals) followed by Hypotrigona gribodoi Magretti (19 %), Meliponula ferruginea Lepeletier (13 %), Lasioglossum ugandicum Cockerell (7 %), Apis mellifera scutellata Latreille (6 %), Allodapula acutigera Cockerell (6 %), Ceratina rufigastra Cockerell (5 %), Ceratina tanganyicensis Strand (5 %), Braunsapis angolensis Cockerell (5 %) , Megachile rufipes Fabricius (5 %), Meliponula bocandei Spinola (5 %) and Seladonia jucundus Smith (5 %). The mean number of species recorded per study site per day ranged between 14 and 49, whereas the abundance ranged between 188 and 1,859 individuals. Study sites in areas with intense land-use had species-poor bee communities compared to sites with medium to low land-use intensities. Study sites with riparian forest fragments and wetlands, or with forest fallows in their vicinity had significantly ( P < 0.05) higher species richness and diversity than sites dominated by small-scale monoculture/polyculture fields or sites dominated by either simple or complex traditional agroforestry systems. An ordination analysis also revealed that bee communities were significantly ( P < 0.01) influenced by the presence of semi-natural habitats (woodlands, fallows) and forest fragments in the surrounding of fields. Thus, natural and semi-natural habitats are of great value for afrotropical farmland bee communities. There is a need to put in place strategies and policies for semi-natural and forest fragments preservation for spatio-temporal stability of pollination services in rural landscapes. Farmers are recommended to increase on-farm trees cover to safeguard and enhance pollination function and services in fields. Mimicking natural vegetation through promoting establishment of forest plantations and village community forestry in rural landscapes is also critical for conserving pollination services. [ABSTRACT FROM AUTHOR]

Reconciling the aims of feeding an ever more demanding human population and conserving biodiversity is a difficult challenge. Here, we explore potential solutions by assessing whether land sparing (farming for high yield, potentially enabling the protection of non-farmland habitat), land sharing (lower yielding farming with more biodiversity within farmland) or a mixed strategy would result in better bird conservation outcomes for a specified level of agricultural production. We surveyed forest and farmland study areas in southern Uganda, measuring the population density of 256 bird species and agricultural yield: food energy and gross income. Parametric non-linear functions relating density to yield were fitted. Species were identified as “winners” (total population size always at least as great with agriculture present as without it) or “losers” (total population sometimes or always reduced with agriculture present) for a range of targets for total agricultural production. For each target we determined whether each species would be predicted to have a higher total population with land sparing, land sharing or with any intermediate level of sparing at an intermediate yield. We found that most species were expected to have their highest total populations with land sparing, particularly loser species and species with small global range sizes. Hence, more species would benefit from high-yield farming if used as part of a strategy to reduce forest loss than from low-yield farming and land sharing, as has been found in Ghana and India in a previous study. We caution against advocacy for high-yield farming alone as a means to deliver land sparing if it is done without strong protection for natural habitats, other ecosystem services and social welfare. Instead, we suggest that conservationists explore how conservation and agricultural policies can be better integrated to deliver land sparing by, for example, combining land-use planning and agronomic support for small farmers. [ABSTRACT FROM AUTHOR]

The article reports and discusses methods used to ascertain vulture populations in Uganda, Africa, from 2011-2012.

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]

The article discusses counts of vulture carcasses in Uganda and a revised proposal for a monitoring protocol. It says that a note by Pomeroy and colleagues reveal that 319 vultures came to goat carcasses at various sites in Uganda in 2003 which were adopted in 2005 since there were no breeding colonies of the said animal in the country, although Bramford and colleagues described in 2009 that there seems to be potential suitable sites. Moreover, counts in 2009 were in four savanna parks with one cow per site unlike in 2003 wherein site used had two sites each with two goat carcasses. It also mentions comparable results in 2003 were similar in 2009 although there were differences in methods used. It suggests that cows are more suitable as bait and more vultures would have counted.

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]

The article reports the outcome of a roundtable discussion highlighting the importance of biodiversity monitoring and the need to regularize monitoring in Eastern Africa and share results. It addresses several issues including what taxa should be monitored, who should monitor and how should the process be designed. It suggests the importance of conducting biodiversity monitoring by all countries for conservation.

The article focuses the roundtable discussion related to ecology in Africa. During the discussion, attendees suggested that the term "Capacity Building" for biodiversity conservation be rephrased as "Capacity Enhancement" because there is knowledge already vested in people. The event also presented ecology research, including topics on the importance of monitoring mammals and birds in Eastern Africa and the significance of scientific and reference collections of animals and plants for biodiversity identification and research.

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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.

Uganda is one of the most species rich countries in Africa because of the presence of several major biomes. However, it is also a country that has lost much of its natural habitat to agriculture. Uganda is a country that has been better surveyed for its biodiversity than many African countries, but despite this, there has not been a comprehensive analysis of the critical sites that contribute to biodiversity conservation at a global, as well as at a national level. We here present such an assessment using mammals, birds, reptiles, amphibians, and plants as surrogate taxa. We identified 36 terrestrial sites that are of sufficient global importance to qualify as Key Biodiversity Areas (KBAs), using the Global Standard for the Identification of KBAs, which complement an additional nine freshwater sites. National red listing of species and ecosystems was used to identify sites of national importance for conservation. We employ a conservation planning approach using Marxan to identify the minimum set of sites needed to conserve all the globally and nationally threatened species and nationally threatened habitats in Uganda. The findings show that most of the remaining natural habitat in Uganda is important for the conservation of globally and nationally threatened species and threatened habitat. Large areas of irreplaceable habitat occur outside protected areas, although more extensive surveys of these areas would likely reduce the area that is irreplaceable. [ABSTRACT FROM AUTHOR]

The article offers information on the retraction notice for the article "Patterns of bee diversity in mosaic agricultural landscapes of central Uganda: implication of pollination services conservation for food security," that was published in the 2013 issue.

In this paper, we argue that bird atlases, and the databases from which they are produced, are becoming increasingly valuable resources – but only in some parts of the world. There is a striking lack of atlases for almost all of the world's species-rich areas, most notably tropical America and tropical Asia. Yet even comparatively modest data sets (we take Uganda as an example) can be used to create an atlas. Further, their data can yield interesting information with clear value for conservation planning. For instance, we can see that Uganda's main savanna parks are quite well-placed in relation to raptor species richness, whilst other species of conservation concern are less well covered. In contrast, the fine-scale data-rich atlas projects in many American and European countries provide detailed information of great value. Taking examples from England, we show some of their uses in planning both for physical developments and for conservation. Repeating atlas projects after an interval of several years highlights changing distributions and, increasingly, changing levels of abundance. We believe that every encouragement should be given to new (and repeat) atlasing projects - but most especially in the tropics. [ABSTRACT FROM PUBLISHER]

In this paper we compare the use of transect counts with a simpler method of investigating bird diversity and numbers, particularly in terrestrial habitats, both natural and non-natural. Transect Counts (TCs) have long been widely used, whereas Timed Species Counts (TSCs), which estimate relative abundance, are comparatively untried. We find that TSCs give results which are comparable to those from TCs in mostrespects, except that they can only be used indirectly for estimating population densities, and they give different measures of diversity. However, TSCs generate data on many more species much faster than do TCs and are therefore more cost-effective in most situations. In particular, TSCs are useful for community studies. We show, for example, that in natural habitats bird populations are positively correlatedwith the amount of woody vegetation, but not with rainfall. Diversity too increases with woody vegetation. Because TSCs are simple, more of them can be made for a given input of time, and hence more distributional data are obtained as an additional benefit. [ABSTRACT FROM AUTHOR]