Showing papers in "Ostrich in 2016"
TL;DR: In this paper, the authors assessed seasonal use of the plantation forest by the understorey bird community in Bunduki Forest Reserve in the Uluguru Mountains and found that the use of plantations by those species that make seasonal altitudinal movements shows that plantation forests can enhance indigenous biodiversity by enabling connectivity between two or more natural forest patches.
Abstract: Plantation forests generally support lower bird diversity than natural forests. However, in some instances the plantations have been found to provide suitable habitat for a number of bird species. In the Eastern Arc Mountains, there is limited knowledge how understorey birds, some of which make seasonal altitudinal movements, use plantations. Using mist netting we assessed seasonal use of the plantation forest by the understorey bird community in Bunduki Forest Reserve in the Uluguru Mountains. Species diversity and capture rates were significantly higher during the cold season than during the hot season possibly due to seasonal altitudinal migration by some species. The use of plantations by those species that make seasonal altitudinal movements shows that plantation forests can enhance indigenous biodiversity by enabling connectivity between two or more natural forest patches. Our findings suggest that in a situation where there is no natural forest, an exotic plantation with suitable indigenous underst...
17 citations
TL;DR: In this paper, the authors used independ- ent nest survey data to test whether changes in reporting rates of Martial Eagles in the Kalahari Gemsbok National Park between the two SABAP surveys were reflected in real change in numbers of nesting pairs.
Abstract: Repeat monitoring is vital to measure biodiversity change. However, monitoring protocols may change, as survey techniques improve or different questions are asked. Such modifications may cause difficulties when examining changes in wildlife populations. The Southern African Bird Atlas Project (SABAP) 1 and 2 are repeat national bird surveys undertaken 20 years apart. These surveys therefore offer unrivalled potential to examine bird population changes in an African context. However, changes in protocols, both spatially and temporally, between the two surveys have raised concerns over using these data to infer population changes. In this study we use independ- ent nest survey data to test whether changes in reporting rates of Martial Eagles in the Kalahari Gemsbok National Park between the two SABAP surveys were reflected in real change in numbers of nesting pairs. From 11 quarter degree squares (QDS), covering c. 8 000 km2, both SABAP and nest surveys suggested a near identical 44% decline. Levels of agre...
16 citations
TL;DR: Monitoring of eight Cape Vulture Gyps coprotheres breeding colonies in South Africa and Botswana took place between 2010 and 2014 using standardised counting methods, suggesting multiple colonies are stable or increasing, but the extinction of peripheral colonies and contraction of the species’ range is alarming and gives evidence for unsustainable population declines.
Abstract: Monitoring of eight Cape Vulture Gyps coprotheres breeding colonies in South Africa and Botswana took place between 2010 and 2014 using standardised counting methods. Counts of breeding pairs, nestlings and fledglings were used to calculate breeding success and general population trends. While our data suggests multiple colonies are stable or increasing, the extinction of peripheral colonies and contraction of the species’ range is alarming and gives evidence for unsustainable population declines. Monitoring efforts chronicled the extinction of the previously large core colony at Roberts’ Farm, which was abandoned as a breeding site in 2013. Standardised monitoring is urgently needed across the entire species range to better understand current population dynamics.
14 citations
TL;DR: The Waterbird Conservation Value (WCV) index as discussed by the authors is a more nuanced approach, sensitive to actual species' abundance rather than counts of "1% threshold" species and considers all species in the assessment.
Abstract: Traditionally, species richness, species diversity, total count, biomass, energy consumption and the Ramsar ‘1% threshold’ have been used to assess the importance of wetlands for waterbirds. Designation of wetlands of international importance (Ramsar sites) based on waterbirds has focused on those species meeting the Ramsar 1% population threshold levels. These levels prioritise a subset of species as being important, with little or no consideration to the contributions of the remaining species’ populations. In this paper, we evaluate and further describe a quantitative method to assess wetland avifaunal importance. Termed the Waterbird Conservation Value (WCV), this index sums the ratio of each species’ abundance to its published 1% threshold across all species to give an overall measure of the ‘value’ of the waterbirds at a wetland. Large values indicate that large proportions of the total populations of waterbird species are present at the wetland. Indices can be evaluated at site and species levels. The WCV is a more nuanced approach, sensitive to actual species’ abundance rather than counts of ‘1% threshold’ species and considers all species in the assessment. The outputs of the WCV index are demonstrated and discussed using a case study from three regions within the East Atlantic flyway. Keywords: conservation assessment, East Atlantic flyway, population index, Ramsar, waterbirds, wetlands
12 citations
TL;DR: In this paper, the authors analysed migration strategies of the Osprey Pandion haliaetus on the poorly studied Eastern European-East African flyway and found that stopovers were made mostly in Europe and less in the Middle East (Turkey) and north-eastern Africa (Egypt).
Abstract: We analysed migration strategies of the Osprey Pandion haliaetus on the poorly studied Eastern European–East African flyway. Four adult birds were equipped with GPS-based satellite-transmitters or data-loggers in their breeding sites in Estonia (north-eastern Europe) and tracked to their wintering grounds in Africa and back, during up to six migration cycles. Departure times, migration routes, as well as wintering and stopover sites varied remarkably between individuals but not much between years. Stopovers (2–30 days) were made mostly in Europe and less in the Middle East (Turkey) and north-eastern Africa (Egypt). The Ospreys did not avoid flying long distances over the sea, and the sea was crossed four times during the night. The current study adds to current knowledge on Osprey migration and should help to concentrate actions on protecting important flyways and stopover locations.
11 citations
TL;DR: In this article, the authors surveyed avifauna in some poorly known forests (12.5-25 ha) located 320-1 300 m above sea level in the Uluguru Mountains to address their conservation importance.
Abstract: Forest fragmentation can lead to extinctions of some species at local levels and is eroding bird diversity at an increasing rate. While there is information on the distribution of forest bird species in most of the Eastern Arc Mountain forests, some forests, particularly the smaller fragments, have not been adequately surveyed. Using mist netting we surveyed avifauna in some of the poorly known forests (12.5–25 ha) located 320–1 300 m above sea level in the Uluguru Mountains in order to address their conservation importance. Proportions of seasonal altitudinal migrants were significantly higher in these lower-altitude forests during the cold season than the hot season. The results suggest that these forests support bird species of conservation concern, most of which are forest dependent and some of which make seasonal movements between high-altitude montane forests and lowland/ foothill forests. These forests are important cold-season habitat of altitudinal migrants and further fragmentation should be hal...
10 citations
TL;DR: In this paper, the authors monitored the nests of the Hooded Vulture Necrosyrtes monachus and White-backed Vultures Gyps africanus in the Olifants River Private Nature Reserve over two breeding seasons in 2013 and 2014.
Abstract: Basic ecological information is still lacking for many species of African vultures The Hooded Vulture Necrosyrtes monachus is known as a rare breeding resident in north-eastern South Africa This study set out to monitor the nests of Hooded Vultures and, secondarily, White-backed Vultures Gyps africanus in the Olifants River Private Nature Reserve over two breeding seasons in 2013 and 2014 A total of 12 Hooded Vulture nests, placed mostly in the tree Diospyros mespiliformis, were found along the Olifants River, with an average inter- nest distance of 076 km Nest success was estimated to be between 044–089 offspring pair−1 y−1 in 2013 and 050–067 offspring pair−1 y−1 in 2014, which are the first estimates for Hooded Vultures in South Africa It is thought that nests of this species have been under-reported due to the fact that they are placed within or below the canopy of densely leafed trees and hence difficult to view from aerial surveys African White-backed Vultures also bred along the Olifants
9 citations
TL;DR: The Egyptian Vulture Neophron percnopterus population in Morocco has undergone a marked decline since the 1980s to the point of nearing local extinction in the twenty-first century as discussed by the authors.
Abstract: The Egyptian Vulture Neophron percnopterus population in Morocco has undergone a marked decline since the 1980s to the point of nearing local extinction in the twenty-first century. A field study of some possible sites for Egyptian Vultures was carried out over six days during June 2014 in the Middle Atlas Mountains, Morocco. We counted a total of 48 Egyptian Vultures at three different localities: two occupied breeding sites and one communal roost that hosted 40 vultures of different ages. A (probable) singe adult bird at the breeding site was located and a previously occupied site was also visited. A preliminary survey amongst local people indicated that threats faced by this species are predator poisoning in some areas, and the use of vulture parts for traditional medicine. Given that the species is considered globally Endangered and populations continue to decline in many areas, the discovered population reported here, although relatively small, is of national and regional (North-west Africa) importan...
9 citations
TL;DR: The data suggest that persistence of the eagles in altered landscapes can be attributed to two main factors: continued availability of a principal prey species and the ability of theEagles to respond to changes in availability by prey switching.
Abstract: The dietary response of African Crowned Eagles Stephanoaetus coronatus to habitat transformation was investigated. Habitat alteration around nests in the Eastern Cape, South Africa, was mapped and nests were assigned to two habitat classes. Prey remains were collected from around nests and identified by comparison with reference specimens and images and descriptions from the literature. Prey proportions were compared between ‘intact’ (n = 6) and ‘altered’ habitat classes (n = 6), and the Shannon–Wiener diversity index was calculated for each. Notwithstanding bias associated with the use of prey remains to investigate diet, the aims of the study were achieved. Rock Hyrax Procavia capensis was the primary prey in both habitat classes. In ‘altered’ habitats, the eagles took a larger proportion of species that are associated with open (e.g. hares Lepus spp.) and altered habitats (e.g. Vervet Monkey Chlorocebus pygerythrus) and a lower proportion of forest specialist species (e.g. Blue Duiker Philantomba monti...
8 citations
TL;DR: A discriminant function was developed, using bill length and depth from a sample of birds sexed from gonad visualisation during post-mortem, which correctly classified 93% of the individuals and correctly assigned 90% of DNA-sexed birds and 91% of Birds sexed by partner measurement comparisons.
Abstract: African Penguins Spheniscus demersus are sexually dimorphic; on average, males are larger than females but measurements overlap making sex determination difficult through observations alone. We developed a discriminant function, using bill length and depth from a sample of birds sexed from gonad visualisation during post-mortem, which correctly classified 93% of the individuals. Cross-validation correctly assigned 90% of DNA-sexed birds and 91% of birds sexed by partner measurement comparisons. The use of discriminant function score cutpoints, while leaving 16% and 29% of birds unclassified, improved accuracy of birds sexed by DNA to 97% and of those sexed by partner comparison to 99%. Bill depth was found to be a discriminating variable. However, two techniques for measuring bill depth are currently in use for African Penguins. While these measurements are correlated (r = 0.85), they differ on average by 1.4 mm hindering accuracy of sex determination when using a discriminant function developed from the...
8 citations
TL;DR: A risk assessment, which included a proposed risk weighting methodology, was conducted at Hosea Kutako and Eros airports, which estimated the probability of an accident/collision as well as the consequence of such a collision as discussed by the authors.
Abstract: At Namibia’s two major airports, Hosea Kutako International and Eros (domestic), 117 bird strike collision incidents were recorded between 2006 and 2010. A risk assessment, which included a proposed risk weighting methodology, was conducted at Hosea Kutako and Eros airports, which estimated the probability of an accident/collision as well as the consequence of such a collision. The assessment included surveys of bird occurrence frequencies as well as pilot interviews. The results of the risk assessments were compared with actual bird strike incidences for each species, frequency of occurrence of birds and pilot perceptions of species risk, in order to find whether risk assessment and pilot perception are reliable measures of potential bird strike incidence. White-backed Vulture Gyps africanus and Helmeted Guineafowl Numida meleagris were the highest risk species at both airports. They were also, after Crowned Lapwing Vanellus coronatus, the species most often observed by pilots. Bird strike records showed...
TL;DR: This article investigated patterns of roost site selection and use for four Southern Ground-Hornbill groups in the Associated Private Nature Reserves, north-eastern South Africa, based on data from GPS-satellite transmitters.
Abstract: Different habitats may be used for the needs of various aspects of an animal’s life. Southern Ground-Hornbill Bucorvus leadbeateri groups announce their presence within year-round territories by calling at dawn from their overnight roost sites. Knowledge on ground-hornbill roosting habits is limited. Groups roost in large trees, apparently close to where they end up after daily foraging. We investigated patterns of roost site selection and use for four Southern Ground-Hornbill groups in the Associated Private Nature Reserves, north-eastern South Africa, based on data from GPS-satellite transmitters. The number of roost sites used per month averaged 15.4 ± 4.7 across all groups, indicating little evidence of strong preferences for specific sites. This number was least when groups were breeding, decreasing throughout the early wet season (October–December) and was lowest during the late wet season (January–March) when actively breeding groups frequently roosted close to the nest (54–83% of roosts <1 000 m o...
TL;DR: The Birds of Ghana: an Atlas and Handbook Book as discussed by the authors was published by Tauraco Press, Liege, Belgium Softcover, illustrations (some colour), colour maps, 713 pages ISBN 9782.87225-007-3.99
Abstract: Book Title: The Birds of Ghana: an Atlas and Handbook Book Authors: Francoise Dowsett-Lemaire and Robert J. Dowsett 2014, Tauraco Press, Liege, Belgium Softcover, illustrations (some colour), colour maps, 713 pages ISBN 978-2-87225-007-3. Price £34.99
TL;DR: Evidence is provided of the existence of patch size/ isolation–occupancy relationships characterised by higher occupancy rate of large patches and distance-dependent dispersal, which decreased with increasing gaps between patches, and controlling deleterious human activities that reduce forest size.
Abstract: The persistence of species taxa within fragmented habitats is dependent on the source–sink metapopulation processes, and forest patch size and isolation are key factors. Unveiling species–patch area and/or species–patch isolation relationships may help provide crucial information for species and landscape management. In this study, relationship between forest patch size and isolation with abundance and occupancy probability of forest-dependent birds was investigated. This study was based within a coastal landscape that faces deleterious human activities such as clearing for agriculture. The study aimed to answer the question of whether the size and extent of isolation of forest patches influence abundance and/or occupancy probability of forest-specialist and generalist birds. Two bird species, namely Tiny Greenbul Phyllastrephus debilis subsp. rabai and Yellow-bellied Greenbul Chlorocichla flaviventris, were used as models. Birds were surveyed using distance sampling methods, and spatial metrics were meas...
TL;DR: Using information-theoretic model selection, it is found that invertebrate abundance was the highest-ranked predictor of territory size and was inversely related, consistent with food value theory of territoriality in the Usambara Thrush.
Abstract: Most tropical insectivorous birds, unlike their temperate counterparts, hold and defend a feeding and breeding territory year-around. However, our understanding of ecological factors influencing territory selection and size in tropical insectivores is limited. Here we examine three prominent hypotheses relating food abundance, food dispersion (spatial arrangement of food items), and habitat structure to territoriality in the Usambara Thrush Turdus roehli . We first compared leaf-litter macro-invertebrate abundance and dispersion, and habitat structure between territories and random sites. We then examined the relation between these same ecological factors and territory size. Invertebrate abundance and dispersion were sparsely and evenly distributed across our study system and did not vary between territories and random sites. In contrast, habitat structure did vary between territories and random sites indicating the Usambara Thrush selects territories with open understorey and closed overstorey habitat. Invertebrate abundance and dispersion within territories of the Usambara Thrush were not associated with habitat structure. We believe the most likely explanation for the Usambara Thrush’s preference for open understorey and closed overstorey habitat relates to foraging behavior. Using information-theoretic model selection we found that invertebrate abundance was the highest-ranked predictor of territory size and was inversely related, consistent with food value theory of territoriality. Keywords: endangered species, food value hypothesis, habitat structure hypothesis, leaf-litter macro-invertebrates, resource dispersion hypothesis, structural cues hypothesis
TL;DR: In this article, a correction factor was applied to the 2013 estimates to reflect the difference between the survey counts and the plotless density estimator (PDE), and the corrected PDE densities are inaccurate for estimating dispersed nests but accurate for estimating clustered nests.
Abstract: Breeding population estimates for three vulture species in Kruger National Park (KNP), South Africa, were made in 2013 using data from aerial censuses and a plotless density estimator (PDE). PDEs are distance-based methods used to assess sparse populations unsuitable for plot-based methods. A correction factor was applied to the 2013 estimates to reflect the difference between the survey counts and the PDE figures. We flew additional censuses across most of KNP and counted all visible nests to assess the 2013 estimates. Survey counts were within 95% confidence limits of corrected PDE estimates for White-backed Vulture Gyps africanus (count: 892; estimate: 904 [95% CI ±162]), at the limit of confidence for White-headed Vulture Trigonoceps occipitalis (count: 48; estimate: 60 [±13]) and outside confidence limits for Lappet-faced Vulture Torgos tracheliotos (count: 44; estimate: 78 [±18]). Uncorrected PDE estimates accurately reflected White-headed and Lappet-faced Vulture nest counts. The clustered patterns of White-backed Vulture nests and dispersed patterns of White-headed and Lappet-faced Vulture nests offer an explanation for these results and means that corrected PDE densities are inaccurate for estimating dispersed nests but accurate for estimating clustered nests. Using PDE methods, aerial surveys over ~35% of KNP are probably sufficient to assess changes in these vulture populations over time. Our results highlight these globally important breeding populations. Keywords: aerial survey, Kruger National Park, population estimates, vultures
TL;DR: Estimates confirmed that BirdLife International Important Bird and Biodiversity Area criteria are met for at least one species, the Sooty Tern, and four of the five seabird species known to breed in São Tomé e Príncipe, occur on the Tinhosas.
Abstract: The Tinhosas islands, in Sao Tome e Principe, host the most important seabird breeding colony in the Gulf of Guinea, but information on its conservation status was hitherto unpublished or anecdotal, the last assessment having been performed in 1997. A two-day expedition to the Tinhosas islands was undertaken to estimate the status of breeding seabirds in 2013. Four of the five seabird species known to breed in Sao Tome e Principe, namely Brown Booby Sula leucogaster, Sooty Tern Onychoprion fuscatus, Brown Noddy Anous stolidus and Black Noddy Anous minutus, occur on the Tinhosas. A decrease of 80% in Brown Booby numbers, possibly due to occasional exploitation, and a 30% increase in Sooty Tern and Black Noddy numbers, were found compared to 1997 data although survey methods differed. Breeding of Brown Noddy and Madeiran Storm-petrel Hydrobates castro remains unconfirmed. Our estimates confirmed that BirdLife International Important Bird and Biodiversity Area criteria are met for at least one species, the S...
TL;DR: In this article, the authors investigated the abundance and density of the Lilian's Lovebird in Liwonde National Park, Malawi using distance sampling (line and point transects) methods and total counts (waterhole and flyway counts) were applied.
Abstract: Monitoring abundance of threatened species is important for conservation planning. Lilian’s Lovebird Agapornis lilianae is a near-threatened small parrot found in mopane Colophospermum mopane woodland. Its population has not been investigated in any part of its range. We investigated the abundance and density of the Lilian’s Lovebird in Liwonde National Park, Malawi. Both distance sampling (line and point transects) methods and total counts (waterhole and flyway counts) were applied. The point count method gave very low numbers and was discontinued after the first year. Line transects conducted during the wet season had the highest density estimates of 17 ± 4.8 lovebirds km−2 of mopane woodland. However, number of observations per transect in each year were low. Waterhole counts had the lowest density estimates (10 ± 3.5 lovebirds km−2). Flyway counts gave an intermediate estimate (13 ± 3.0 lovebirds km−2). The total population of Lilian’s Lovebirds in Liwonde National Park is therefore estimated to be ab...
TL;DR: The results show that the Gulf of Gabès hosts important numbers of waterbirds with different ecological requirements, which confirms the importance of this gulf as a wintering area for Palearctic waterbirds.
Abstract: Although the Gulf of Gabes is recognised as an Important Bird Area, several aspects of the ecology of waterbirds inhabiting this area still need to be investigated. We observed how waterbird foraging guilds varied among habitats. In total, 49 species belonging to 16 families were recorded. Winter visitors accounted for 73% of counts. The avifauna was dominated by shorebirds (52% of records), followed by large wading birds (25%), open-water birds (18%) and waterfowl (5%). However, the structure of local waterbird communities and their composition in terms of foraging guilds varied according to habitat type. The bird communities of sandy beaches were dominated by open-water birds, whereas large mudflats were dominated by shorebirds, and wadi estuaries showed a more even representation of foraging guilds. Locally rare species had narrow distributions, whereas locally abundant species were found widely within the gulf. For four species the 1% population level criterion of the Ramsar Convention was exceeded. O...
TL;DR: In this article, the seasonal elevational movements of the Eastern Olive Sunbird Cyanomitra olivacea were studied along an elevational gradient from 600 to 1 500 m above sea level in the Uluguru Mountains, Tanzania, between May 2005 and February 2006.
Abstract: Little is known about the seasonal elevational movements for most tropical avifauna species. Seasonal elevational movements of the Eastern Olive Sunbird Cyanomitra olivacea were studied along an elevational gradient from 600 to 1 500 m above sea level in the Uluguru Mountains, Tanzania, between May 2005 and February 2006. The recapture of ringed individuals along an elevational gradient across seasons provided evidence for the seasonal elevational movement of the Eastern Olive Sunbird in the Uluguru Mountains and the first documented evidence for this species in the Eastern Arc Mountains as a whole. Due to forest fragmentation and lack of corridors connecting high- and low-altitude forests in the Uluguru Mountains, the results have implications for conservation of the forest along the entire elevational gradient as well as for other forest bird species that have been documented to make seasonal elevational movements in the Uluguru Mountains and the entire Eastern Arc Mountains.
TL;DR: The surprisingly high proportion of Rock Hyraxes and low proportion of Vervet Monkeys caught in emerging habitat may indicate that African Crowned Eagles nesting in this habitat are adapting to a more specialised feeding strategy compared with those nesting in habitats that are more natural.
Abstract: The aim of this study was to investigate the species composition of prey caught in the forest, savanna and emerging habitats in which African Crowned Eagles Stephanoaetus coronatus breed in KwaZulu-Natal province, South Africa. At the 17 nest sites, the remains of 195 prey individuals were collected. The five dominant prey species caught were Rock Hyrax Procavia capensis , Vervet Monkey Chlorocebus pygerythrus , Blue Duiker Philantomba monticola , Greater Canerat Thryonomys swinderianus and Bushbuck Tragelaphus scriptus . All of these species respond positively to urban expansion. Only eagles that nested inside protected areas were recorded preying on domestic animals. In terms of biomass, Bushbuck was one of the dominant taxa, and the remains of an estimated 28.8 kg Bushbuck ram was found under a nest. The surprisingly high proportion of Rock Hyraxes and low proportion of Vervet Monkeys caught in emerging habitat may indicate that African Crowned Eagles nesting in this habitat are adapting to a more specialised feeding strategy compared with those nesting in habitats that are more natural. Future studies should investigate how and why prey proliferates in emerging habitats and examine the association between land uses and the diet of African Crowned Eagles. Keywords: African Crowned Eagle, diet, emerging habitat, Stephanoaetus coronatus , urbanisation
TL;DR: The distribution, breeding population, habitat use and current threats of the Grey-necked Picathartes were re-assessed by revisiting the 91 breeding sites identified during the first and only survey of the species in 1987, estimating a breeding population of 164 individuals across 82 breeding sites.
Abstract: The Grey-necked Picathartes Picathartes oreas is a globally threatened bird species in Africa with a wild population of less than 10,000 individuals. The Nigerian population, which has been poorly studied, is restricted to the forest of Cross River. This study re-assessed the distribution, breeding population, habitat use and current threats of the Grey-necked Picathartes by revisiting the 91 breeding sites identified during the first and only survey of the species in 1987. We estimated a breeding population of 164 individuals across 82 breeding sites. Only 72 breeding sites were found in the localities where 91 had been registered in 1987. Thirteen (18%) of these 72 sites were no longer active and showed evidence of human disturbance. The occurrence of Grey-necked Picathartes’ nest sites was positively predicted by higher number of emergent trees, larger rocks and negatively related to disturbance matrices. Similarly, larger colony sizes were associated with high canopy cover and rock height. Also, the p...
TL;DR: A survey carried out in spring 2015 in Morocco confirmed the decline of the Great Bustard Otis tarda population, with a 40% decline over the last decade.
Abstract: A Great Bustard Otis tarda survey carried out in spring 2015 in Morocco confirmed the decline of this highly endangered population. Bustards were only seen at two of the seven leks occupied ten years ago. The total number of birds counted was 40-44, which represents a 40% decline over the last decade. The sex-ratio was still strongly female-biased (1 male: 3 females), but less than in previous surveys, which suggests that trophy hunting has not been the major mortality cause in recent times. The productivity was 0.29-0.33 juveniles per female, the highest ever recorded in this population, suggesting that breeding success doesn’t represent the main problem for the survival of this population. Based on the recent development of the power line network at some areas, the main threat today is probably collision with power lines. Reducing this mortality cause should be considered a high conservation priority. Keywords: conservation, endangered species, Great Bustard, Otis tarda, population decline
TL;DR: The globally Vulnerable Grey Parrot has been seen in Kampala, Uganda’s capital city, in increasing numbers in recent years, and it is believed that at least some of the birds seen inkampala are wild.
Abstract: 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.
TL;DR: A decrease in annual survival was noted with increasing population size on both islands (Cousin: t = −3.09, p < 0.05), which is a likely consequence of increased territory disputes and competition for food.
Abstract: The Seychelles Magpie Robin Copsychus sechellarum was once one of the most threatened birds in the world, but was downgraded from Critically Endangered to Endangered after a long-term recovery programme was successfully implemented. Comprehensive long-term monitoring of this species was conducted on the islands of Cousin and Cousine over an 18-year period. We report here on the species longevity and annual survival at these two sites. The oldest recorded individual was a male who died on Cousine Island on 28 September 2000 at just under 16 years old. This individual was recorded to have hatched on Fregate Island on 3 January 1985, before being translocated to Cousine Island in 1995. Mean annual survival rates over an 18-year period were 81.6% on Cousin and 77.9% on Cousine islands. A decrease in annual survival was noted with increasing population size on both islands (Cousin: t = −3.09, p < 0.05; Cousine: t = −2.71, p < 0.05), which is a likely consequence of increased territory disputes and competition for food. Keywords: annual survival, Copsychus sechellarum , Cousin Island, Cousine Island, longevity, Seychelles Magpie Robin
TL;DR: A comparison of results from the current study to other nesting observations made approximately seven decades earlier suggest that the breeding season appears to have shifted to an earlier period, potentially due to the fruiting phenology and abundance of Maesopsis eminii.
Abstract: The breeding season diet and nesting characteristics of the Silvery-cheeked Hornbill Bycanistes brevis are poorly known. To further understand these aspects of the breeding biology of this hornbill species, 14 nests were studied in and around Amani Nature Reserve located in the East Usambara Mountains, Tanzania. Nesting tree species were identified and the diet composition of nesting hornbills was evaluated between July and November 2001. The ejecta from each nest were collected, inventoried, identified (as completely as possible) and enumerated. Food items were categorised as plant, vertebrate or invertebrate. Plants, represented largely by fruits, were the dominant food type (n = 861), followed by invertebrates (n = 306; mainly millipedes and beetles), and vertebrates (n = 15; mainly smaller birds and chameleons). A comparison of results from the current study to other nesting observations made approximately seven decades earlier in the same area suggest that (1) the invasive tree species Maesopsis emin...
TL;DR: In this paper, the authors report on a first avifaunal survey of the isolated montane habitats of Mt Mecula (1 442 m), Niassa National Reserve, notable as the only currently protected montane area in northern Mozambique.
Abstract: The montane forests of northern Mozambique’s isolated massifs are inhabited by numerous range-restricted and threatened bird species, but until recently were extremely little-known. We report on a first avifaunal survey of the isolated montane habitats of Mt Mecula (1 442 m), Niassa National Reserve, notable as the only currently protected montane area in northern Mozambique. Mount Mecula’s moist forest is small (approximately 136 ha in total) and patchy, and although known botanically to have some montane affinities, was found to support an avifauna more typical of riparian forests of medium to low altitude. The only montane forest species recorded was Lemon Dove Aplopelia larvata. Other montane elements included Vincent’s Bunting Emberiza (capensis) vincenti, one of six species recorded new to the Niassa National Reserve list. Overall, it appears that despite its intermediate location, Mt Mecula does not represent a biogeographical ‘stepping stone’ for montane forest bird species. This probably owes to ...
TL;DR: The Grey Crowned Crane Balearica regulorum was uplisted to globally Endangered in 2012 as discussed by the authors and there is urgent need to determine the threats they face at local levels for their conservation.
Abstract: The Grey Crowned Crane Balearica regulorum was uplisted to globally Endangered in 2012. There is urgent need to determine the threats they face at local levels for their conservation. I conducted formal point-count surveys around the wetlands of eastern Uganda and observed no cranes. Groups of cranes were encountered when following directions from local inhabitants. Results from a questionnaire survey suggested that cranes make use of most of the wetlands in the region, and that the birds occur in small flocks averaging 6–8 individuals. Wetland loss through farming was reported to be the main threat, but I also documented poisoning, roost disturbance, and the collection of eggs and chicks. Rigorous conservation and education programs are needed to ensure the long-term survival of cranes and storks in this region.
TL;DR: It is speculated that the occurrence described here may represent a case of mistaken identity by the female Wattled Lapwing when choosing a nest scrape, since there seems to have been little benefit to the usurping species of taking over an already occupied nest.
Abstract: I report an instance of usurpation of a Crowned Lapwing Vanellus coronatus nest by a pair of African Wattled Lapwings Vanellus senegalensis. The nest, which originally contained a single Crowned Lapwing egg, eventually contained an additional three Wattled Lapwing eggs, before it was predated. Although parents of both species were observed in the vicinity of the nest, video monitoring showed that the Wattled Lapwings incubated all four eggs. Detection of embryonic heart rate suggested that all the eggs were probably viable up until the nest was destroyed. Nest usurpation in shorebirds is rare, and given the easily accommodated nest requirements and minimal costs of nest construction in these species, is difficult to explain. I speculate that the occurrence described here may represent a case of mistaken identity by the female Wattled Lapwing when choosing a nest scrape, since there seems to have been little benefit to the usurping species of taking over an already occupied nest.
TL;DR: In this paper, the authors surveyed roads throughout agroecosystems in Swaziland for Black-shouldered Kites and looked at habitat selection in a used versus available framework, finding that kites selected for savannas and tall herbaceous vegetation but did not show preferences for or against land use types.
Abstract: A decline in many African raptor populations may contribute to loss of ecosystem services such as pest control. The Black-shouldered Kite Elanus caeruleus stands out as an exception, experiencing range expansions due to its proclivity for agricultural landscapes. We surveyed roads throughout agroecosystems in Swaziland for Black-shouldered Kites and looked at habitat selection in a used versus available framework. We found that kites selected for savannas and tall herbaceous vegetation but did not show preferences for or against land-use types. We also found a significant relationship with kite presence and low tree densities in the immediate vicinity of a perch site. Singles, pairs and fledgling kites were observed in agricultural landscapes, suggesting that although they are not selecting for these areas in proportion to their availability, they are foraging in it. This may be a boon for farmers who implement ecologically based rodent management programs.